DEUTSCHE NORM
DIN VDE 0210
December 1985
Planning and Design of Overhead Power Lines with Rated Voltages above 1 kV
/-
,£5.17:621.3.027.4:001.4 -·
. DEUTSCHE NORM
December 1985
Planning and Design of Overhead Power DIN Lines with Rated Voltages above 1 kV VDE 0210 This standard that is approved by the Managing Committee of the Association of German Electrical Engineers (VDE e.V.) is thus also a VDE Specification within the meaning of VDE 0022. It has been incorporated into the VDE Specifications Series under the above-mentioned number and has been notified in the Elektrotechnische Zeitschrift (etz). This· standard supersedes VDE 0210/5.69 No relevant· regional or international standards exist concerning the scope of this standard. The contents of the standard was published in the draft DIN 57210/VDE 0210/4.83.
Commencement of validity This standard (VDE Specification) applies as of lst December 1985. Contents 1 2 3 4 5
Scope Definitions General requirements _conductors Conductor accessories 6 Insulators, insulator sets 7 Accessories for insulator sets and other conductor attachments 8 Towers 9 Foundations 10 Earthing 11 Clearances within t~e overhead power line 12 Clearances in rural areas ' 13 Clearances and specifications for line design in the proximity of building installations and traffic routes 14 Special specifications for crossings and approaches Appendix A: Galvanizing of towers and other components Quoted standards and other .documents Previous editions Amendments Comments
Page 2 2 5 5 12 13
'
14 16 43 62 62 64
66 78 79 81
87 87 88
Continuation page 2 to 99
German Electrotechnical Commission within DIN and VDE
(DKE)
Page 2 DIN VDE 0210 PLANNING AND DESIGN OF OVERHEAD POWER LINES WITH RATED VOLTAGES ABOVE 1 KV 1. SCOPE This standard applies to planning and design of overhead power lines with rated voltages above l kV. It also applies to telecommunication cables installed on supports of overhead power lines. 2. DEFINITIONS 2.1 Overhead line The term overhead line includes the entire installation for transmission and ·distribution of electrical power above ground, consisting of supports and line components. Supports comprise towers, their foundations and earthing. Line components comprise overhead conductors and insulators together with their accessories. 2.2 Towers and poles Towers or poles are parts of the support~. Towers include the tower body, earthwire peak(s) and crossarm(s). According to Clauses 2.2.1 to 2.2.7 they serve for following purposes. 2.2.1 Suspension tower line.
supports
the conductors
in
a
straight
2.2.2 Angle suspension tower serves as suspension support for the conductors where the line changes direction 2.2.3 Angle tower carries the resulting conductor tensile forces where the line changes direction. 2.2.4 Section tower and angle section tower carry the conductor ter.sile forces in line direction or in the resultant direction, respectively, and serve additionally as rigid points in the line. 2.2.5 Terminal tower forces on one side.
carries
the
total
conductor
2.2.6 Special tower serves for one or several of tioned purposes. 2.2.7 Guyed tower is additionally order to stabilise the tower body.
provided
the
tensile
above men-
with staywires in
2.2.8 Net working force of a tower or pole is the permissible total horizontal force at the tower top after deduction of a force equivalent to the wind load on the tower structure in terms of the tower top. 2.2.9 Uplift or downward forces are represented by the components of the conductor tensile forces due to differing heights of the suspension points. They act against or in direction of the conductor deadweight forces, respectively.
DIN VDE 0210 Page
3
2.2.10 Additional load allows for the loading of conductors , insulators and warning markers by glaze, rime or snow. It may be assumed that the additional load is equally distributed along each span. (Internationally additional load is usually referred to as ice load). 2.2.11 Span length is the horizontal distance between two adjacent supports. (When determining the horizontal distance of the fixing points of a conductor the angle of the 6rossarm to the line must be considered accordingly). 2.2.12 Wind span of a tower is the arithmetic mean value of the lengths of the two adjacent spans. all components which are not 2.2.13 Tower eq~ipment summarizes part of the tower structure or of the conductors. Insulators and accessories are in this category.
2.3 Foundations Foundations are parts of the supports and fulfil the task of transferring the structural loads from the tower to the sub~oil, and, at the same time, protecting the tower against critical movements of the subsoil.
2.3.1 Compact foundation single foundation.
accommodates
the tower body within one
2.3.2 Separate footing foundation provides individual foundations for each leg member of the tower. 2.3.3 Working load of a foundation is the load transferred from the tower-to the foundation for a given loading case. 2.).4 Failing load of a foundation is the load under which the foundation fails. The failure is defined by inadmissible large foundation movements and occurs in the transition range between stable and unstable state of equilibrium. 2.4 Conductors Conductors are the bare or covered, insulated or earthed cables strung between the supports of an overhead line irrespective of whether they are alive or not. 2.4.1 Bundle conductor is an arrangement of two or more subconductors used instead of a single conductor and kept at approximately constant spacing over their entire length. 2.4.2 Failing load of a conductor 0,95 times the theoretical is failure strength according standards DIN 48201, DIN to 48204 and DIN 48206. 2.4.3 Unit deadweight force related to the cross-section (QLK) is the force of the deadweight of 1 m of conductor per mmz of cross-sectional area.
2.4.4 Nominal cross-section of a conductor is the cross-sectional parameter used for the designation of the conductor.
Page 4 DIN VDE 0210 2.4.5 Actual cross-section of a conductor is the cross-section of metal resulting from the conductor design without considering tolerances due to manufacturing. is the theoretical value 2.4.6 Tensile stress of a conductor the conductor tensile force which results from the division of by the actual cross-section. 2.4.7 Maximum working tensile stress is the horizontal component of the selected maximum conductor tensile stress which occurs under the conditions of installation and the specified loading assumptions. 2.4.8 Permissible maximum working tensile stress accordfhg to Table 3 Col~mn 6 is the horizontal component of the conductor tensile stress. 2.4.9 Long-term tensile stress is the tensile stress which a conductor can withstand for one year without failing. 2.4.10 Everyday stress is the horizontal component of the conductor tensile stress which occurs at the annual mean temperature (normally +lO"C) without wind load. 2.4.11 Maximum working tensile force of a conductor is the product of actual cross-section and maximum working tensile stress. 2.4.12 Conductor temperature is the temperature of a conductor due to ambient temperature, wind and electrical load current. 2.4.13 Sag of a conductor is the vertical distance between the conductor and the alignment of the conductor suspension points (suspension sets) or attachment points (tension sets) at the supp9rts. 2.5 Insulators Insulators serve as insulation of live conductors against earth or other live components. The definitions for insulators are given in DIN VDE 0441 Part 2 and DIN VDE 0446 Part 1. 2.5.1 Multiple insulator set lator strings.
is
an arrangement of several insu-
2.5.2 Routine test load of an insulator is the static force to which every insulator shall be subjected according to the conditions specified in DIN VDE 0446 Part 1. 2.6 Accessories Accessories serve for the mechanical attachment, the electrical connection and the protection of conductors and insulators. The definitions for fittings, accessories for conductors and accessories for insulator sets and for other conductor attachments are laid down in DIN VDE 0212 Part 50.
DIN VDE 0210 Page
5
2.6.1 Accessories for conductors are components which are directly connected to the conductor and serve tQ terminate, to suspend and to joint the conductors. Vibration protection fittings and bundle spacers are also in this category. 2.6.2 Accessories for insulator sets and other conductor attachments are components which serve to connect the tension or suspension components (accessories for conductors) with the supports. In case of insulator sets the components to connect insulators are also in this category. The insulators, however, are excluded. Usually, these are all components mechanically loaded by the conductor tensile force or the conductor deadweight and arranged between the assembly of the tension or suspension clamp and the ~irst detachable part at the support, for example the jointing pin or the U-bolt, the insulators excepted. Arcing and corona protection fittings are also included.
2.7 Layout of an overhead line 2.7.1 Section
is the part of an between two adjacent ~ection supports.
overhead
line
situated
2.7.2 Span is the part of an overhead line situated between two adjacent supports.
2.7.3 Crossing span is the part of an overhead line over or under a crossed installation situated between two adjacent supports. 2.7.4 Clearances according to Clauses 11, 12 and 13 are minimum clearances and shall not be infringed under conditions of maximum sag at the selected conductor temperature according to Clauses 4.3.1 and 4.3.2, respectively.
3. GENERAL REQUIREMENTS All components of an overhead line shall be selected, designed and installed in such a manner that they perform reliably during operation under the climatic conditions to be regularly expected, under the maximum operating voltage, under the effects of the electrical load current and under the short circuit loadings to be expected. If necessary the influence of atmospheric and switching overvoltages shall be taken into consideration. These requirements are met if an overhead line is designed and installed according to the following stipulations. DIN VDE
0105
Part
1
applies
to
operation
and
maintenance.
4. CONDUCTORS 4.1 Rating 4.1.1 Thermal rating Material and cross-section Of a conductor shall be selected such that the conductor will not reach a temperature which would lead to an inadmissible reduction of its mechanical strength while being subjected to the maximum electrical load current
Page 6 DIN VDE 0210 of ambient conditions or of the maximum short taking account to be expected. circuit load condition The standards of contain data for conductors.
the series DIN 48201, DIN 48204 and DIN 48206 the current-carrying capacity of standardized
DIN VDE 0103 applies to the mechanical and thermal short circuit strength. Departing from this specification the permissible conconductor temperatures shall be limited to the values given in Table 1. Table 1.
Permissible conductor temperature in case of short-circuit loading
.
Material
Permissible conductor temperature ·c at short circuit
Homogeneous conductors
Copper AAC AAAC Steel
170 130 160 200
Reinforced conductors
ACSR AACSR
160 160
Type of conductor
..
4.1.2 Mechanical rating 4.1.2.1 Loading according to maximum working tensile stress At a temperature of -5"C with the normal additional load according to Clause 8.1.1.2 and at -20"C without additional or wind loads and at +5"C and wind load according to Clause 8.1.2.1 ~the horizontal component of the conductor tensile stress shall not exceed the permissible maximum working tensile stress according to Table 3 Column 6. Additionally, under these conditions the conductor tensile stress at the support positions may exceed the permissible maximum working tensile stress by not more than 5 %. In case of approximately level spans a check is not necessary if the sag according to Clause 4.3 does not exceed approximately 4 % of the span length. At -5"C with the increased additional load ace. to Clause 8.1.1.2 and at -5"C with the normal additional load combined with wind load ace. to Clause 8.2.1.3 and at -5"C with the increased additional load combined with wind load ace. to Clause 8.2.1.3 the permissible maximum working tensile stress ace. to Table 3 -Column 6 need not be adhered to, however, the specifications related to the long-term tensile stress ace. to Clause 4.1.2.2 shall be met.
DIN VDE 0210 Page -
7
For selfsupporting metal-reinforced telecommunication aerial cables the permissible maximum working tensile stress shall be selected with regard to Table 3 Column 6 taking account of material and design of the supporting reinforcement. 4.1.2.2 Loading according to long-term tensile stress At -5"C with three times the normal or twice the increased additional load ace. to Clause 8.1.1.2 or at -5"C with the normal additional load combined with wind load ace. to Clause 8.2.1.3 or at -5"C with the increased additional load combined with wind load ace. to Clause 8.2.1.3 the conductor tensile stress at the support positions shall not exceed the loqg-term tensile stress ace. to Table 3 Column 8 whereby the higher value of stress will apply.
_ For selfsupporting metal-reinforced telecommunication aerial cables the long-term tensile stress shall be selected related to Table 3 Column 8 taking care of material and design of the supporting reinforcement. 4.1.2.3 Loading according to everyday stress
-
At the annual mean temperature, which can be assumed to be +lO"C normally, the horizontal component of the conductor tensile stress without wind load should not exceed the everyday stress ace. to Table 3 Column ~c:-Depending on the design of the suspension fittings and on the efficiency of the vibration protection the horizontal component of the conductor tensile stress may exceed the everyday stress ace. to Table 3 Column 7 by up to 3..2J_tn individual cases. In case of selfsupporting metal-reinforced telecommunication aerial cables the everyday stress shall be selected in relation to Table 3 Column~, depending on material and design of the supporting reinforcement. 4.1.2.4 Stress due to aeolian vibrations Conductors are excited to vibration by laminar windflows which may lead to damag~ by failures of individual strands and, eventually, of the whole conductor. Occurrence and intensity of the vibration to be expected depend on the material, design and cross-section of the conductor, on the magnitude of the everyday stress, on the local wind and terrain conditions, on the design of the suspension arrangements and on the fittings used as well as on the span length and on the height of the conductors above gr·ound level. When selecting the everyday stress ace. to Clause 4.1.2.3 there will be only a small risk of vibration failure of reinforced conductors made of aluminium and steel as well as in case of homogeneous conductors made of copper, of steel, of copper wrought alloys or of aluminium clad steel, assuming
Page 8 DIN VDE 0210 favourable environmental conditions and a suitable design of the suspension arrangements. In case of lines susceptible to vibration possible damage can be effectively counteracted by provision of vibration protection fittings. Conductors with a small proportion of steel, homogeneous conductors made of aluminium or aluminium alloy and reinforced conductors made of aluminium alloy and steel, conductors with diameters larger than 25 mm as well as conductors in spans longer than 500 mare more susceptible to vibration. If an increased susceptibility to vibration has to be assumed or has been observed the design of the suspension set and of the damping devices shall be suitably selected in order to guarantee an effective protection of the conductors. 4.2 Conductor make up 4.2.1 Materials The materials for standardized conductors are specified by the relevant DIN standards. Where non-standardized conductors are made up by materials the mechanical and electrical characteristics of which correspond to Table 3 and to the DIN standards, a proof of their qualification is not necessary. Where materials are used which deviate from the mechanical and electrical data given in Table 3 and the DIN standards their characteristics and their qualification for the individual case of application shall be proved. 4.2.2 Properties The properties and dimensions of standard conductors are specified in standards of the series DIN 48200, DIN 48201, DIN 48203 as well as in DIN 48204 and DIN 48206. For non-standard conductors the properties and suitability for the individual case of application shall be approved. This also applies to self-supporting reinforced telecommunication aerial cables ace. to DIN VDE 0818.
DIN VDE 0210 Page
9
4.2.3 Minimum cross-sections Table 2. Minimum cross-sections Material
Nominal cross-section mm 2
ACSR ace. to DIN 48204 AAC ace. to DIN 48201 Part 5 AACSR ace. to DIN 48206 AAAC ace. to DIN 48201 Part 6 Copper ace. to DIN 48201 Part 1 Copper wrought alloy ace. to DIN 48201 Part 2 Steel ace. to DIN 48201 Part 3 Aluminium clad steel ace. to DIN 48201 Part 8
35/6 50 35/6 35 25 25 25 25
Single-wire conductors shall not be used. 4.2.4 Tests For testing · of conductors the standards of the series DIN 48203 are mandatory. 4.3 Sag 4.3.1 Maximum sag shall be the greater of the values resulting from a conductor temperature of -s·c with normal or increased additional load ace. to Clause 8.1.1.2 or from a conductor temperature of +40"C without additional load. 4.3.2 In case of overhead lines for which a high electric current is likely to occur in summer a higher conductor temperature, in excess of +40 ·c, shall be considered when evaluating the maximum sag. 4.3.3 If the sag is calculated using the specific characteristics of the conductor, the data shown in Table 3 apply for standard conductors. In case of non-standard conductors the unit deadweight related to the cross-section expressed by the unit kg/(m*mm 2 ) will be converted to the unit weight force related to the cross-section (QLK) expressed by the unit N/(m*mm 2 ) by multiplying by the factor 10. 4.3.4 During their life the conductors will suffer permanent elongation (creep) resulting in an increase of the sag. At no time shall this increase of sag cause the clearances to fall below the specified values.
'U
Table 3. Composition, mechanical characteristics, permissible maximum working stress, everyday stress and ultimate long-term stress for standard conductors ace. to DIN 118201, DIN 48204 and DIN 48206
Ill ()q
ro .......
Conductor type and rna terial
0
2
1 Crosssectional ratio
Stranding
3 Unit deadweight force related to cross-section QLK
ACSR ace. to DIN '48204
1,4
and
AACSR (A1drey/ Steel) ace. to DIN 48206, respectively
Coefficient of thermal expansion Et -6
(!2_) K
14/7 111/19
0,0491
1,7
12/7
0,0466
15,3
4,3
30/7
0,0375
6,0
6/1 26/7
0,0350
5 Effective modulus of elasticity E
6
8
7
Permissible maximum working stress
Everyday stress
tl
kN/mm
N/mm
I
2
N/mm
l
2
.tl [rJ
N/mm
ACSR AACSR
240
270
90
104
401
464
107
220
255
84
102
368
435
17,8
82
140
190
57
69
240
328
19,2 18,9
77
120
175
56
67
208
300
110
1\.)
2
....... 0
ACSR AACSR
81
0,0336
19,6 19,3 19,4
74 70 68
llO
165
52
63
189
284
·n,3
48/7
0,0320
20,5
62
95
155
44
165
265
14,5
115/7
0,0309
20,9
61
90
148
40
53 50
152
255
23,1
7217
0,0298
21,7
60
80
-
35
-
130
-
60
7 19 37
z < 0
2
ACSR AACSR
15,0
H
Ultimate long-term stress
24/7 54/7 54/19
7,7
AAC ace. to DIN 48201 Part 5
(~) m.mm
4
0,0275
61 91
23,0
57
70
30
120
55 ----
-------
-
I
Continued from Table 3. 2
1 Conductor type and rna terial
Crosssectional ratio
Stranding
Unit dead- ' weight force related to cross-section QLK
AAAC (Aldrey) ace. to,DIN 48201 Part 6
Copper ace. to DIN 48201 Part 1
4
3
(~) m.mm
'
Coefficient of thermal expansion Et -6
(.!Q_)
K
7 19 37 61
Copper wrought alloy (Bronze I • . • Bronze I II) ace. to DIN 48201 Part 2
7 19 37 61
Steel St I-St IV ace. to DIN 48201 Part 3
7
Effective modulus of elasticity E
kN/mm 2
8
1
Pennissi ble maximum working stress N/mm 2
Everyday stress
N/mm 2
Ultimate long-term stress N/mm 2
60
1
19 37 61 91
6
5
0,0275
23,0
57 140
44
240
55
.
113 105 0,0906
17,0
175
85
300
100 113 105 100
I
400
235
Bz II III
295
100
500 0
620
365
:-i
:z: <:
Aluminium clad steel ace. to DIN 48201 Part 8
180 0,0792
11,0
7 19
II
175
19 0' 0671
13,0
I
159
St III IV 567
160 280 lJ50 550
120 130 150 137
0
320 560 goo 1100
[<]
0 N t-'
0
'"0 Pl oq
1112
37 61
(I)
157 L___~
J
t-' t-'
Page 12 DIN VDE 0210 5. CONDUCTOR ACCESSORIES
5.1 Rating 5.1.1 Thermal rating Conductor accessories shall be selected in such a manner that they will not reach a higher temperature than the conductors themselves when the maximum permissible electrical load current flows and that the temperature rise will not lead to an inadmissible reduction of mechanical strength when subjected to maximum expected short circuit load. 5.1.2 Mechanical rating 5.1.2.1 Attachment of the conductors at pin-type insulators Accessories serving for attachment of conductors at pin-type insulators shall be rated to withstand the conductor tensile forces which result from the loads on the conductor ace. to Clauses 8.1 and 8.2. Additionally they shall reliably sustain the conductors in case of unbalanced tensile forces ace. to Clause 8.2.2. This does not apply to acceBsories which due to their design should enable slipping of the conductors. If the continuous conductor (main conductor) is jointed on both sides of the pin-type insulator with an auxiliary conductor which itself is fixed to a second insulator the connection of both conductors may only be rated for the maximum working tensile force. At angle positions the conductors shall be arranged such that the insulator is internal to the angle formed by the conductor. 5.1.2.2 Attachment of conductors at insulator sets Deadend clamps shall sustain the conductor with 2,5 times the maximum working tensile force or with 85 % of the conductor failing load, which ever be the lower value. Suspension clamps shall be rated for 2,5 times the forces acting on the conductor ace. to Clause 8.1. Additionally the suspension clamps shall reliably sustain the conductors in case of unbalanced tensile forces ace. to Clause 8.2.2. This does not apply to suspension clamps which are designed to enable the conductor to slip. 5.1.2.3 Conductor joints Conductor joints loaded by tensile forces shall sustain the conductor with 2,5 times the maximum working tensile force or with 85 % of the conductor failing load, which ever be the lower value.
DIN VDE 0210 Page 13 5.2 Materials, design and testing Conductor accessories according to DIN VDE 0212 Part 50, DIN VDE 0212 Part 51, DIN VDE 0212 Part 52, DIN VDE 0212 Part 53 and DIN VDE 0212 Part 54.
shall
comply
with
the
requirements
6. INSULATORS, INSULATOR SETS 6.1 Rating 6.1.1 Electrical rating Insulators and insulator sets shall be rated such that they comply with the electric requirements according to DIN VDE 0111 Part l and DIN VDE 0111 Part 2. The insulation level shall be stipulated by the Operator of the overhead line. 6.1.2 Mechanical rating The insulators and insulator sets shall be rated mechanically for the effective forces which result from the maximum loads ace. to Clauses 8.1 to 8.3. Thereby, the rating factors specified below shall apply. The failing load must be higher than or equal to the effective maximum force multiplied by the rating factor a or , the rputine test load must be higher or equal to the effective maximum force multiplied by the rating factor b. 6.1.2.1 Line post insulators and pin-type insulators (type A and B) Line post insulators and pin-type insulators may only be used at suspension poles or at angle suspension poles, however, not· at section poles. The rating factor a shall be equal to 2,5 related to the failing load. 6.1.2.2 Long-rod and solid core-type insulators (string insulators type A) and open-air composite insulators The rating The rating load.
factor factor
a shall be 3,12 related to the failing load. b shall be 2,5 related to the routine test
6.1.2.3 Cap and pin-type insulators (string insulators type B) The rating factor a shall be 3,12 related to the electromechanical failing load or to the failing load. The rating factor b shall be 1,87 related to the routine test load.
Page 14 DIN VDE 0210 6.1.2.4 Multiple insulator sets Multiple insulator sets comprise two or more insulator strings. The permissible loading of an insulator set comprising n strings may be taken at maximum as n-times the permissible loading of an individual insulator string. It is assumed that the total load of a multiple insulator set is as far as possible equally distributed over the individual insulator strings. In case of failure of an insulator string a distribution of the total load as equally as possible over the remaining insulator strings shall be guaranteed, the rating factors for the remaining tension loaded insulators may be reduced to 50 % of the values specified in Clauses 6.1.2.2 and 6.1.2.3, any expected dynamic forces and bending moments shall be duly counteracted. 6.2 Materials and design Materials and design of insulators shall be selected such that they withstand atmospheric effects. For standard insulators the materials and design are specified in the DIN standards. In case of non-standard insulators their properties and their suitability for a given application shall be approved individually. 6.3 Testing · -~ /
DIN VDE 0441 Part 2 or DIN VDE 0446 Part 1 apply to testing in order to verify that the requirements are met.
1. ACCESSORIES FOR INSULATOR SETS AND OTHER CONDUCTOR ATTACHMENTS 7.1 Rating 7.1.1 Thermal rating The accessories for insulator sets and for other conductor attachments shall withstand the expected short-circuit loading. Under the maximum expected short-circuit loading they shall not reach a temperature which would lead to an inadmi~sible reduction of their mechanical strength. 7.1.2 Mechanical rating 7.1.2.1 Accessories for pin-type insulators Accessories serving to attach the insulators at the poles shill be rated for at least 2,5. times the forces which result from the maximum loads ace. to Clauses 8.1 to 8.3.
DIN VDE 0210 Page 15 For s:andard insulator pins the permissible loadings stated in the DIN standards shall be met (see for example DIN 48044, DIN 48045). If pin-type insulators are fixed at angle poles made of wood a design of pins adopting through-bolts with washers on both sides shall be selected. 7.1.2.2 The
Accessories attachments
for
insulator
sets
and
other
conductor
accessories shall be rated for the forces resulting from the loads according to Clauses 8.1 to 8.3 multiplied by the rating factors according to Table 4.
maximu~ releva~t
The minimum failing loads of standard accessories are specified in the DIN standards. In addition, permissible working forces for turnbuckles are specified in DIN 48334. Turnbuckles shall not be loaded in bending. Table 4. Rating factors for accessories of insulator sets and other conductor attachments Material Structural steel ace. to DIN 17100, heat-treatable steel ace. to DIN 17200, cast steel ace. to DIN 1681
Rating faC'tor 3,3
Malleable cast iron ace. to DIN 1692 Spheroidal graphit cast iron ace. to DIN 1693 Part 1
4,0
'
Aluminium 'tlrought alloy ace. to DIN 1725 Part 1
3,3
/
Aluminium casting alloy ace. to DIN 1725 Part 2 *)
4,5
Copper-tin and copper-tin-zinc casting alloys ace. to DIN 1705
4,0
Copper wrought alloys low-alloyed ace. to DIN 1766
3,3
Copper-aluminium casting alloys ace. to DIN 1714 with 0 at least 12 % 5 *) draft at present
3' 3
~
For non-standard components it shall be proved that their failing loads comply with the specified requirements. Acc~ssories for distribution of far as possible.
multiple insulator sets shall guarantee equal forces over the individual insulator strings as
In case of failing of an insulator string of a multiple insulator set the rating factors of the remaining tensile loaded accessories of ·insulator strings may be reduced to 50 % of the values specified in Table 4, an e~ual distribution of the total load over the remaining insulator strings should be guaranteed as far as possible.
Page 16 DIN VDE 0210 7.2 Materials, design and testing Accessories shall comply DIN VDE 0212 DIN VDE 0212 DIN VDE 0212
for with Part Part Part
insulator sets and other conductor attachments the requirements according to 50, 53 and
54.
8. TOWERS
8.1 Loading assumptions Towers shall be rated according to their function and to the appropriate loading cases described as follows. 8.1.1 Vertical loads 8.1.1.1 Permanent loads The deadloads of towers, of the equipment and of the conductors resulting from the adjacent span lengths act as permanent loads. Upward and downward forces due to the conductor tensile forces shaJl re accordingly considered. 8.1.1.2 Additional loads In case of conductors it is necessary to distinguish between normal and increased additional load. The normal additional load shall be taken as (5+0,l*d) N per l m conductor or subconductor length, where d is the conductor diameter in mm. An increased additional load shall be allowed for if it occurs regularly. It depends on the terrain through which the line runs and may reach many times the normal additional load. When stipulating the increased additional load ob~ervations of previous years and the special topographical and meteorological conditions of the area of the transmission line have to be considered. In case of insulators the normal additional load shall be taken as 50 N per 1 m length of insulator string. For radar markers and aerial warning balls with aerodynamically favourable shape (for example sphere, double cone) the normal additional load shall be assumed in form of a 1 em thick layer of ice distributed over the total surface. In case of other shapes the ice load shall be assumed according to the geometrical form. The unit weight force of the ice shall be assumed as 0,0075 N/cm 3 • For towers no additional load needs to be assumed. 8.1.1.3 Erection and maintenance loads The erection and maintenance loads of crossarms shall be taken as not less than 1,5 kN in case of suspension towers and angle ~uspension towers and 3 kN in case of all other tower types. In case o~ lattice steel structures these forces shall act at the
DIN VDE 0210 Page 17 individually most unfavourable nodes of the lower chords of one crossarm face, and in all other cases in the axis of the crossarms at the attachment points of the conductors. For all members which can be climbed and are inclined with an angle less than 30• to horizontal an erection and maintenance load of 1,5 kN acting vertically in the centre of a member shall be assumed, however, \-lithout any other loads. In this case the conditions apply.
permissible stresses for exceptional loading
8.1.2 Horizontal loads 8.1.2.1 Wind load. The wind direction shall be horizontal, the wind load in kN shall act perpendicularly to the surface exposed to the wind. For ( rnductors or subconductors the wind load followc- as IV= Ct if d L IV= Ctlfd(80+0.6L)
for spans up to 200 m for spans above 200m,
in kN in kN ··
where: cf aerodynamical drag coeffcient which depends on the shape and type of surface of the structural component exposed to wind (see Table 6). To all not individually mentioned shapes the respective values ace. to DIN 1055 Part 4 shall apply. kN/m 2
q
v 2 /l600 dynamic wind pressure in where v means the wind velocity in m/s
A
surface exposed to wind in m2
d
diameter of conductor or subconductor or diameter of the additional load assumed to be circularly shaped.
L
span length in shall be used.
=
(see Table 5) (
m. When analysing the towers the wind span
Table 5. Specifications for the dynamic wind pressure Height of the transmission line above ground
Height of the camponents above ground
m up to 20 0 to 200
m up to above
15 15 to
0 above 40 above 100 above 150
0,55 0 '7 0
20
to 40 to 100 to 150 to 200
Dynamic wind pressure q in kN/m 2 Towers ConducCross arms tors Insulators
.... . "·
.
0,70.~
0 '9 0 1,15 1,25
0,44 0,53 0,53 0,68 0' 8 6 0,95
I,
' ·.,
~
Page 18 DIN VDE 0210 Table 6.
Aerodynamical drag coefficient
Aerodynamical drag coefficient c 1
Component
/
Flat truss structures consisting of profiles
l' 6
Square and rectangular lattice towers consisting of profiles
2,8
Flat truss structures consisting of tubes
1,2
Square and rectqngular lattice towers consisting of tubes
2,1
Tubular steel, reinforced concrete and wood poles with circular cross-section
0,7
Tubular steel and reinforced concrete poles with square and rectangular cross-section
1' 4
Tubular steel and reinforced concrete poles with hexagonal or octagonal cross-section
1,0
Double and A-shaped poles consisting of steel tubes, reinforced concrete and wood with circular cross-section in the plane of the pole part of the pole exposed to wind lee~ard
0,7
part of the pole
for a < 2 d *) for a = 2 d m up t o a for a > 6 dmm
0
=
6 d
m
0,35 0,7
rectangular to the plane of the pole for a< 2 d m
0,8
Conductors up to 12,5 mm diameter
1,2
Conductors above 12,5 up to 15.8 mm diameter
1,1
Conductors above 15,8 mm diameter
1,0
Conductor with other than circular cross-sections
1,3
Radar markers and aerial warning balls with diameter between 300 mm and 1000 mm
0,4
*)
a, d , ace. to DIN 48351 Part 1 m
/
DIN VDE 0210 Page 19 The wind load on the conductors shall be evaluated with regard to their height at their attachments. In especially wind-prone areas an increased load according to the local conditions shall be considered.
8.1.2.2 Loading by conductor tensile forces The conductor tensile forces each individual loading case.
shall be determined according to
8.2 Loading cases for tower bodies When analysing tower bodies the loads assigned to the individual loading cases in Table 7 shall be assumed as acting~simul taneously. For ~ach member the loading case shall be selected which produces the maximum loading. If section towers are systematically subjected to permanent unforces or to torsional loadings this shall be balanced tensile considered. If initially the circuits of towers are to be only partially installed tr1en this shall be considered whPf"l analysing the towers. For tower types which are not included in Table 7 the loading cases shall be applied according to the utilization of the towers.
8.2.1 Normal loading 8.2.1.1 General Here, the Table 7.
loading
cases
MN
1
to
MN 5 apply as indicated in
In case of lattice towers with square or rectangular cross-section only the. surface of the lattice faces exposed to Hind need to be considered. The wind pressure on lattice faces, the plane of which extends into the direction of wind, may be neglected.
8.2.1.2 Quartering wind Quartering wind shall be considered for all towers. In case of square and rectangular tower structures the wind direction shall be assumed under an angle of 45" in terms of one tower face. The wind load acting on the tower may be substituted by its components perpendicularly to the tower faces exposed to the wind. These componentstshall be evaluated from the dynamic wind pressure, the aerodynamical drag coefficient increased by 10 % and from the respective area exposed to wind multiplied by the cosine of the angle between the wind direction and the normal line to the tower face. Hence, the area of the members within the tower face shall be taken into account as area exposed to the wind. Simultaneously, 8D % of the wind load on the conductors ace. to loading case MN 2 shall be assumed in direction
Page 20 DIN VDE 0210 of the axis of crossarms. The 'q_ther forces simultaneously in case of a quartering wind from loading case MN 4 of Table 7.
to be assumed shall be taken
8.2.1.3 Wind on ice-covered conductors For all towers, excepted suspensions towers with a height of the conductor attachments up to 15 m, the wind action on ice-covered conductors shall also be assumed, allowing by 50 % of the wind load ace. to Clause 8.1.2.1 on towers, on equipment and on conductors covered with normal or increased additional load ace. to Clause 8.1.1.2. The unit weight force of the ice may be taken as 0,0075 N/cm 3 , and the aerodynamic drag coefficient as l,fi. 8.2.2 Exceptional loading Here the loading cases MA 1 and MA 2 given in Table 7 apply. All towers with the exception of single-, double- and A-shaped poles '.made of wo1r0 shall be designed for a random reduction of one or several conductor tensile forces which will create bending and/or torsion. In
detail
the following assumptions apply as appropriate.
8.2.2.1 General In the loading case MA 1 the tensile force of one conductor shall be assumed to be reduced on one side ace. to Clauses 8.2.2.2 or 8.2.2.3 if up to two three-phase AC circuits are installed ·an the towers. If more than two three-phase AC circuits are installed on the towers, half of the loading ace. to Clauses 8.2.2.2 or 8.2.2.3 shall be considered additionally for the third and the fourth as well as for the fifth and the sixth circuits. The position of the unbalanced conductor tensile forces acting in the same direction shall be assumed in such a manner that the most unfavourable loadings occur in the individual members. Independently of the arrangement of the circuits reduction of the tensile force of one conductor considered for one crossarm.
only the has to be
In case of DC and monophase AC circuits provisions shall be made analogously in respect of the number of conductors. 8.2.2.2 Suspension and angle suspensions towers Loading case MA l The tensile force of one conductor at normal or increased additional load shall be assumed reduced by 50 % on one side in case of single conductors. In case of bundled conductors the tensile force shall be assumed reduced by 35 % on one side in case of lengths of insulator sets up to 2,5 m and by 25 % in case of lengths of insulator sets above 2,5 m. In case of earth wires a reduction of 65 % shall be assumed.
Table 7. Loading cases of tower bodies To1-1er type
Normal loading (MN) ace. to Clause 8.2.1 Loading case
Loading case MN 2
Loading case MN 3
Loading case
Loading case
MN 4
MN 5
Permanent loads, additional loads
Permanent loads
Permanent loads
Permanent loads
Permanent loads, additional loads·
Hind load on toHer and equipment in direction of the axis of crossarm
Hind load on toHer, equipment and condue tors in direction of the axis of crossarm
Hind load on toHer and equipment rectangularly to the axis of crossarm
Quatering Hind load on toHer, equipment and condue tors ace. to Clause 8.2.1.2
Hind load in direction of the axis of crossarm on toHer, equipment and conductors Hith additional load ace. to Clause 8.2.1.3
MN 1 Suspension toVJers
Exceptional loading (MA) ace. to Clause 8.2.2
r-
5~
(__,
-1·
s· (__.
-\· _) c f' "
+-5'c_
:::
--S,c -1 v.; Angle suspension toVJers and angle toHers
Permanent loads, additional loads
Permanent loads
Permanent loads
Permanent loads, additional loads
Loading case MA 2
Permanent loads, additional loads
Conductor tensile forces ace. to Clause 8.2.2.2 Permanent loads, additional loads C! H
Wind load on toHer and eq~ipment in direction of the axis of crossarm Continuation see Page 22
Permanent loads
Loading case MA 1
Hind load on toHer, equipment and conductors in direction of the axis of crossarm
v! in d
load on tm-1er, equipment and conductors rectangularly to the axis of cros:;arm
Quartering Hind load on toHer, equipment and conductors ace. to Clause 8.2.1.2
Wind load in direction of the axis of crossarm on toHer, equipment and conductors with additional load ace. to Clause 8.2.1.3
z < 0
(l1
0 N t-' 0
'U
n> OQ (J)
{\)
t-'
Continued from Table 7.
'"0 ~
OQ (])
Normal loading 01N) ace. to Clause 8.2.1
ToHer type
Exceptional loading (~~) ace. to Clause 8.2.2
N N
0
Loading case
Loading case
MN 1
MN 2
Loading case MN 3
Loading casejLoading case
MN 4
MN 5
Loading case MA 1
Loading case MA 2
H
z
< 0
Angle suspension towers and angle toHers (cont.)
Conductor tensile forces resulting from additional loads
Conductor tensile forces at +5·c and wind load
Conductor tensile forces at +5·c and wind load
Conductor tensile forces at +5·c and wind load
Conductor tens i l e forces . resulting from additional load and wind load ace. to Clause 8.2.1.3
Section towers and angle section toHers
see angle suspension towers and angle toHers
see angle suspension towers and angle towers
Permanent loads additional loads
see angle suspension tov1ers and angle toviers
see angle suspension toHers and angle towers
~ ...
;
\
Conductor tensile forces at angle suspension toHers ace. to Clause 8.2.2.2, at angle towers ace. to Clause 8.2.2.3
I Permanent
loads, additional
loads
Hind loads on to1-1er and equipment in direction of the axis of crossarm thirds of the higher conductor tensile forces at one side resulting from additional loads. These forces act in the centre of the toHer
Tv:o
Conductor tensile forces ace. to Clause 8.2.2.3
[T]
0 N 1-' 0
Continued from Table 7. Normal loading (t'lN) ace. to Clause 8.2.1
ToHer type
Terminal t01-1ers
Loading case
Loading case
MN l
t1N 2
Exceptional loading (MA) ace. to Clause 8.2.2
Loading base MN 3
Loading case
Loading case
Loading case
Loading case
MN 4
MN 5
MA l
MA 2
Permanent loads, additional loads
Permanent loads additional loads
Permanent loads
Permanent loads, additional loads
Wind load on tower and equipment in direction of the axis of crossarm
\-lind load on tO\·ler and equipment rectangularly to the axis of c r·ossar·m
Qua tering Hind load on tovrer, equipment and conductors
Hind load in direction of the axis of crossarm on tovrer, equipment and conductors vJith additional load ace. to Clause 8.2.1.3
Conductor tensile forces at one side of all conductors resulting from additional loads
Conductor tensile forces at one side of all conducLors rcsu] tinr; from additional
Conductor tensile forces at one side of all conductors at +5°C and Hind load
Conductor tensile forces at one side of all conductors from ad ditional load and wind load ace. to Clause 8.2.1.3
lOilClS
I
Permanent loads, additional loads
Conductor tensile forces at one side ace. to Clause 8.2.2.3
CJ H
z
< 0 trJ 0 I'J I-'
0 "0
Pl
aq CD I'J
w
Page 24 DIN VDE 0210 torsional loading of towers is prevented or recuced by If the suitable measures (such as release clamps, rotating crossarms l stays etc.) the effect achieved of such measures may be taken into consideration. Loading case MA 2 The tensile force of all conductors shall be assumed to be reduced by 20 % on one side in case of pin-type insulators and suspension towers with lengths of insulator sets up to 2,5 m and by 15 % in case of suspension towers and lengths of insulator sets above 2,5 m. For earth wires a reduction of 40 % shall be assumed.
8.2.2.3 Angle towers,
section towers and terminal towers
Loading case MA r The tensile fore~ of one conductor with normal or increased additional load shall be assumed to be reduced on one side by 100%. Loading case MA 2 The tensile forces of all reduced by 40 % on one side.
conductors
shall be assumed to be
8.3 Loading cases for crossarms and earthwire peaks When analysing the crossarms and earthwire peaks the loads assigned to the individual loading cases in Table 8 shall be assumed as simultaneously acting. For each structural component the loading case shall be selected which produces the maximum loading. In case of crossarms and earthwire of section to~ers peaks which systematically experience permanent unb2lanced tensile forces those forces shall be considered. In case of crossarms of which will initially the conductors be installed partially this situation shall be considered when analysing the crossarm. For crossarms of tower types which are not included in Table 8 the loading cases shall be assumed according to the utilization of the towers. 8.3.1 Normal loading In this case the loading cases QN 1 to QN 3 apply as Table 8.
indicated in
8.3.2 Exceptional loading Here the Table 8.
loading
cases
QA
1
to
QA
3 apply as indicated in
All crossarms of towers shall be designed for a random reduction of the tensile force of one conductor which will create a loading of the crossarm in the dire~tion of the conductors as well as for the failing of one insulator string of a multiple insulator set. Additionally, all crossarms shall be designed for erection and maintenance loads ace. to Clause 8.1.1.3.
Table 8. Loading cases for crossarms and earthwire peaks Tov1er type
Normal loading (QN) ace. to Clause 8.3.1 Loading case
QN l Suspension tm-1ers
Loading case QN 2
Loading case
QN 3
Permanent loads, !Permanent loads additional loads
Permanent loads
Wind load in direction of the axis of crossarm on crossarm, equipment and conductors Hith additional load aec. to Clause
Hind load on cross arm and equipment rectangularly to the axis of crossarm
Wind load on crossarm, equipment and conductors in direction of the axis of crossarm
8.2.1.3 Angle suspension tm·le rs and angle tov1ers
Permanent loads, !Permanent loads !Permanent loads additional loads Hind load in direction of the axis of crossarm on crossarm, equipment and conductors with additional load ace. to Clause 8.2.1.3
Wind load on crossarm, equipment and conductors in direction of the axis of crossarm
Conductor tenConductor tensile forces from,sile forces at additional and +5"C and wind Hind load ace. load to Clause 8.2.1.3
Wind load on crossarm and equipment rectangularly to the axis of crossarm
L Exceptional loading (QA) ace. to Clause 8.3.2 Loading case QA 1
Loading case QA 2
Loading case QA 3
Permanent loads, !Loads ace. to additional loads loading cases QN 1 to QN 3 or loaqing case QA 1 and failing of one insulator string ace. to Clause 8.3.2.1
Permanent loads, erection and maintenance loads ace. to Clause 8 .l.l. 3
Conductor tensile forces ace. to Clause
Conductor tensile forces ace. to Clause
8.3.2.2
8.3.2.2
Permanent loads, !Loads ace. to additional loads loading cases QN l to QN 3 or loading case QA l and failing of one insulator string ace. to Clause 8.3.2.1
Permanent loads, erection and maintenance loads ace. to Clause· 8.1.1.3 0 H
z < 0
[r)
Conductor tensile forces at +5"C and wind load
Condue tor tensile forces at angle suspension tO\·Iers ace. to Clause 8.3.2.2 at angle toHers ace. to Clause 8. 3. 2. 3
Conductor tensile forces at angle suspension toHers ace. to Clause 8.3.2.2 at angle toHers ace. to Clause 8. 3. 2. 3
0 1\..)
t--'
0
., Pl ()q
ill 1\..)
Vl
Continued from Table 8.
'"U
Ill ()q
Tower type
Normal loading (QN) ace. to Clause 8.3.1 Loading case QN 1
I
Loading case QN 2
Exceptional loading (QA)
~~~.
t:.r:;
Clause 8.3.2
Cll 1\)
·I
Loading case ' , QN 3
Loading case QA 1
Loading case QA 2
I Loading case QA 3
0\
0 H
z
Section towers and angle section towers
Loads ace. to ;Loading cases QN 3 and failing of one insulator string ace. to Clause 8.3.2.1
Permanent loads, additional loads see angle suspension towers and angle towers
see angle suspension towers and angle towers
Wind loads on crossarm and equipment in direction of the axis of crossarm Higher one-sided conductor tens i l e force of one conductor with addi tiona! ' load at tacking most unfavourably and simultaneously two thirds of the higher one-sided conductor forces of the other conductors with additional load
/
-
Permanent loads, erection and maintenance loads ace. to Clause 8 .1.1. 3
Conductor tensile forces ace. to loading case QN 3
< 0
trl
0 1\)
I-'
0
Continued from Table 8. Tower type
Normal loading (QN) ace. to Clause 8.3.1 Loading case QN 1
Terminal towers
Loading case QN 2
Loading case Q!'l 3
Permanent loads, additional loads
Permanent loads, additional loads
Wind load in d irec ti on of the axis of crossarm on crossarm, equipment and conductors with additional load ace. to Clause 8.2.1.3
Wind load on crossarm, equipment rectangularly to the axis of crossarm
Conductor tensile forces at one side of all conductors with additional load and Hind load ace. to Clause 8.2.1.3
Conductor tensile forces at one side of all conductors with additional load
Exceptional loading (QA) ace. to Clause 8.3.2 Loading case QA 1
Loading case QA 2
Loading case QA 3
Loads ace. to loading cases QN 1 or QN 3 and failing of one insulator string ace. to Clause 8.3.2.1
Permanent loads, erection and maintenance 1 oads ace. to Clause 8 .l.l. 3
Conductor tensile forces ace. to loading case QN 3 0 rl
z
<
0
M
0 f\J
...... 0 '"U
Ill OQ C1> (\)
-.J
Page 28 DIN VDE 0210 8.3.2.1 General Only the tensile force of one conductor at one crossarm needs to be assumed to be reduced. The unbalanced conductor tensile force shall be assumed in such a manner that the most unfavourable loadings are produced in the individual members. Also, only the failing of one insulator string of a multiple insulator set at the same time needs to be assumed, however, at that point of action which produces the most unfavourable loading of each individual member. 8.3.2.2 Suspension and angle suspension towers The assumptions acc.to Clause 8.2.2.2, loading case MA 1 apply to the unbalanced tensile forces. A reduction of the conductor tensile force on obe side by 65 % shall be considered for the earthwire forces. In addition to the permanent loads the normal or increased additional load ace. to Clause 8.1.1.2 shall be taken into account. 8.3.2.3 Section towers The
DIN VDE 0210 Page 29 8.4.2 Analysis, permissible stresses 8.4.2.1 Determination of member forces When determining the forces in the members of the tower body of a four-legged tower the following simplified assumptions may be used. Special significance must be given to the application of external loads. Horizontal loads may be separated into the direction of the tower faces and may be distributed equally on the two faces concerned. Each tower face may than be analysed for the proportion of loading assigned to it as a plane truss. In case of leg members the forces resulting from two adjacent tower faces have to be summed up. If a horizontal load Z results in a torsional moment Md related to the axis of the tower body, the horizontal forces may be determined ace. to Fig. 1. For these horizontal forces, each individual tower face may be treated as a plane truss structure.
Z(1 + ~)
Aid
=
H,
!ltd z =fa+ 2
H2
HJ""' Md
2h
jl 1-1.
-"'"1
g.
Aid
=
2 d-
Z
2
1. Horizontal loads acting on the tower body resulting from a torsional moment
When using this approach the ratio alb shall not exceed 1,5. The shape of the tower must be prismatic or correspond to a truncated pyramid. At all crossarm levels and at changes of slope of leg members, horizontal bracings shall be provided and their adequacy shall be proven.
Page 30 DIN VDE 0210 8.4.2.2 Materials Generally, only the structural steel types St 37-2 and St 52-3 ace. to DIN 17100 shall be used as material for overhead line towers. Other types of structural steel may only be used if their mechanical characteristics, chemical composition and suitability for welding are clearly shown by the manufacturer's quality requirements or factory standards and if that structural steel can be assigned to one of those steel types mentioned in the first sentence of this clause. In all other cases, suitability requires approval, for example in form of an official certification by the civil engineering authorities. A manufacturer's certificate according to DIN 50049 for the types of steel to be used for welded components is the minimum requirement. Steel for structural parts of minor importance is excepted. (For selection of steel qualities see DAST-Instruction 009). 8.4.2.3 Permissible stresses The permissible stresses for St 37-2 and St 52-3 as well as for the corresponding bolts and rivets are shown in Table 9. 8.4.2.4 Utilization of high-strength bolts High-st~ength
bolts may be used for shearing/bearing joints ace. to DIN 18800 Part.l) having a tolerance between hole and bolt of up to 2 mm. These joints can be designed without prestressing or with prestressing not less than 0,5 * FV (for FV see Table 9, Note 1). The prestressing force need not to be checked. (S~-joints
Materials, performance and analysis of shearing/bearing joints shall comply with DIN 18800 Part 1/03.81 Clauses 2.3 and 7.2.1. The permis~ible stresses can be taken from Table 9. When using high-strength bolts for friction grip joints (GV-joints ace. to DIN 18800 Part 1), with or without loadings in direction of the axis of the bolts, the stipulations according to DIN 18800 Part 1 and Part 7 shall be met. The normal loading shall be assigned to loading case H and the exceptional loading to the loading case HZ. 8.4.2.5 Welded joints For welded joints the stresses according to DIN 18800 Part 1/ 03.81, Table 11, loading case H, are permissible in case of normal loading. In case of exceptional loading 1,375 times these stresses are permissible. DIN 18800 Part 1 applies to the analysis and structural design of DIN 18808 applies to tubular welded joints. In addition shall be sections. Additionally, the CAST-Instruction 009 adopted. 8.4.2.6 Rating of tensile loaded members When evaluating the tensile stress of a member consisting of an angle section which is connected by one rivet or by one bolt
DIN VDE 0210 Page 3l only the cross-section of the connected angle leg reduced by the cross-section of the hole shall be considered. In case of a connection with two or more rivets or bolts arranged in one leg of an angle 0,8 times that net cross-section which results by deduction of the holes from the cross-section shall be considered.
8.4.2.7 Rating of axially loaded compression members Members of lattice steel towers may be considered as straight axially loaded compression members and shall be rated according to DIN 4114 part 1. For compression loaded leg members of lattice steel towers the eccentricity of the load application may be disregarded provided reference is made to the mean centroidal axis. In case of compression bracing members of lattice steel towers consisting of one single angle (for example members between leg members or between chords) being connected by one of the angle legs the eccentricity of load application may be disregarded. For single applies
compression 0
=
loaded
members
the following relation
F
..t ::5 °perm
(t) • -
Hhere: F
absolute value of the maximum compression force occurring in the member in N
A
total
cross-section
of
the
member
compression stress in N/mm 2 ace. to Table 9 for the analysed loadirig case and the material selected.
0 perm permissible ;
w
buckling coefficient depending on the material and the slenderness ratio A. For A:: 250, W can be taken from DIN 4114 Part 1.
The slenderness ratio is not limited for members of lattice steel towers. For A > 250
applies. Hhere: E
0
A
modulus of elasticity, for steel perm
permissible compression stress for St 37-2 for St 52-3
E
= 210000 N/mm 2
0 perm
=
0 perm
=
160 N/mm 2 240 N/mm 2
slenderness ratio
For members with A < 20 a compression analysis need not to be carried out. The buckling coefficient W may be taken as 1:
Page 32 DIN VDE 0210 8.4.2.8 Rating of eccentrically loaded compression members In case of members with uniform cross-section which are systematically loaded eccentrically by a compression force F acting along one of the principal axes or which, in addition to a compression force F, are loaded by a bending moment M acting in a principal plane, whether or not it is dependent on F, the virtual extreme fib-re stress acceding to o
=
ttl· F M -A- + 0.9 W :$ Operm
d
shall not exceed the stress u for compression and combined bending compression according P!SmTable 9. Thereb~, it has been assumed that buckling occurs in the plane of the acting moment and that the centre of gravity of the member cross-section has the same or a smaller distance to the extreme tension fibre than to the extreme compression fibre. The bending moment M and the section modulus Wd shall be related to a principal axis of the total cross-section. For a cross-section of a member the centre of gravity of which is closer to the extreme compression fibre than to the extreme berdirg tension fibre the following two d~nditions must be '" satisfied: (U. F . M o
=
-A-
,•,
tu·F
+ 0.9 W
.
':
...
"
~-
:5 uperm
;.
300+2.-l M o=.~+. 1000 .·wSuperm
....
.; ~- ' . '.:.~. l .~......~-----···--~~--'~·1: . :.~. ·-
'
where Wd and ·w.z"are· the. ~~-~-tJ~n-mOdp~J ·.of the gross cross-section related to the extreme compression'1ibre and the extreme tension fibre, respectively ... i • · ~
<,>, ' ../. ·:•·; .'·. ·. ~:· . ,~ f) . :, ,· ""~JFL :_;-:,. . .
··
8.4.2.9 Rating of
.
rr
..
com~6und
...
compressiori members
·!:.,·
):,~;·>···
; or ..... t~-; .angle sections
for compression members ·can~i~ting stan'dard · ·bolt's··-··are-···used. to_ . _jbiil the stay' plates instead of rivets, -fitted ::bolts or welding, 'the buckling length evaluated a c c or d i n g .to ·~Cl au s e 8 • 4 • 2 . 11 s h a 11 be i n c r e as e d by t h e fa c to r 1. 1 while the :formula .: · ·-': 1: ' ,~·.. >~ ~~\;: l ~ . .. .. . ... ... ...... ~ .. ~-- .. -- -)., = ~ . .. ,, '
',:::
·:·.\
applies for the slenderness ratio of the sub-member as before. When connecting a compound compression member to a leg member or to a gusset plate the end stay plate may be omitted if the conne~tion is carried out by welding or by rivets or by fitted bolts. When connecting with standard bolts the end stay plate may be omitted if the distance to the next stay plate is not more than 0,75 times the theoretical interval between stay plates. compression members When the structural design of compound these requi~ements the members may be calculated complies with according to the following rules including also Clause 8.4.3.4.
DIN VDE 0210 Page 33 Table 9. Permissible stresses for components made of steel Component
1
RiVets
Components Steel structure
Compression and Bending compression, Tension and Bending tension Shear
Normal loading
Material
Type of loading
Eolts
Exceptional loading
N/rnrn 2
1
I 1160 1240
St 37-2 St 52-3
I
220 330
I
I 104 156
143 214
160 240
220 330
St 37-2,USt36 4.6 320 St 37-21 >~ 5.6 320 St 52-3! 5.6. 480
440 440 600
4.6 126 5.6- 168 10.9- 270
173 231 371
4.6 5.·6 10. 9. 4.6· 5.6•10.9·-
280 280 280 280 420 420
385 385 385 385 575 575
10.9 - 380
522
10.9
783
St 37_:21 St 52-31
I
I
Round head rivets ace. to DIN 124
Shearing
Fitted bolts ace. to DIN 7968
Bearing
lust36 1
4.6 5.6
!
Shearing Hexagon bolts ace. to DIN 7990 · High-stre~gth bolts ace. to DIN 6914 without pr~-L stressing ·: ': I / Bearing . ..
'
St St St St St St
t
37-2 37-2 t 37-2 ~~ 52-3 1 52-31 52-31 i
,~
:
High-strength bolts ace. to DIN 6914 with prestressing
Bearing
~0,5xFvl)
Hexagon bolts ace. to DIN 7990
St 37-21
St
52-31
570
171
Tension
Fitted bolts ace. to DIN 7968
5.6
150
206
10.9
410
563
\oo~
High-strength bolts ace. to DIN 6914 without prestressing 1) Fv ace. to DIN 18800 Part 1/03.81, Table 9
Column 2 and DIN 18800
Part 7/05.83, Table 1 Column 2, respectively.
Page 34 DIN VDE 0210 Compound compression members which consist of m sub-members, the cross-section of which is provided with a material principal axis x-x, may be calculated against buckling transversely to this material axis as a single compression member. As far as buckling transversely to the non-material principal axis y-y is concerned the member can be treated as a single compression member with a virtual slenderness of ·
" +2 m . J.,2 "'y
/.yi =
where A is the slenderness ratio of the individual sub-member. 1 In case of a lattice system adopted for the connection of the sub-members the effective working length, and in case of stay plates their centre-to-centre distance, shall be assumed as the buck l i n g 1 eng t h s k • For i t he, min i mum r ad ius of g y rat ion of a 1 1 sub-member shall be used. / If the leg member is formed by several angle sections and if the angle legs are parallel to the tower faces then the leg member shall be checked against buckling in each of the tower faces. Fo.r the slenderness ratio the maximum of the values Ax or A and A . or A . , respectively, shall be adopted. y
Y1
X.l.
\.
'\
members consisting of two angle sections arranged in cruciform the buckling of which is not constrained to a definite direction due to connections within the buckling length need only to be checked against buckling transversely to the material axis x-x. In case of compound compression members with two immaterial axes the higher value of the two slenderness ratios A y 1. .·.shall be .used. . ' . ' . ' ... ' Compress~on
,
.
'
All stay plates ~nd bracings as well as their connections shall be rated such that under action of the virtual member shear force ... .
the stresses permissible not be exceeded. Where:
w Y1.
for the considered loading case shall
buckling coefficient according to the virtual slenderness ratio. I
For stay plates and filler plates of compound compression members it is sufficient to prove that their connections are able to withstand the force s
T= Q··I L'
resulting from virtual member shear force Q., where 1
·s
e
interval of the stay plates and spacing of the centroidal lines of the angle sections of the sub-members.
DIN VDE 0210 Page 35 When checking the connections of the stay pla~es the moment due to the eccentric application of the force T shall be considered. In the case of compression members consisting of angle sections arranged in cruciform the stay plates may be arranged staggered at right angles or in parallel. 8.4.2.10 Buckling length of leg members If the ends of the members are restrained to preclude lateral displacements, the buckling length sK of leg members of lattice steel towers shall be the effective working length sx or sD . If there is a definite direction of buckling due to the connections within the buckling length, the moment of inertia shall be related to the axis which is perpendicular to that direction. If the leg members consist of equal-leg angle sections and if the bracings are arranged according to Fig. 2a or 2b the analysis of the leg members shall be based on the moment of inertia I • X
If the bracing is arranged according to Fig. 2c or 2d the minimum moment of inertia I~ shall be considered. If the bracing is arranged according to Fig. .2a or 2b the buckling length sk of the leg members may be assumed to be equal to s if the slenderness ratio X
~:.r
.
·,, ...
does not exc~e~~8o. ·...
b)
d)
Fig. 2. Bu
Page 36 DIN VDE 0210 In case of A > 80, sk = s . may be assumed if the member forces increase dow~wards along tfie tower body and the lengths of members in the upper part of a tower or a tower section are not longer than in the lower part. Otherwise sk = 1,1 s shall be • X assumed. 8.4.2.11 Buckling length of the bracing members In case of single warren or double warren bracing the buckling length sk = 0,9 s (s = effective working length) applies as mentioned 'in DIN 4114 Part 2/02.53, R i 6. 48, if their ends are fixed rigidly they are sufficiently restrained in direction of buckling and their cross-sectional area is smaller than that of the leg members. Sufficient restraining is provided for example if the leg and bracing members consist of angle sections. In case of members of double warren bracing one of which is compression loaded and the other tension loaded the crossing point may be considered as rigid in the tower face as well as rectan~ularly to that plane if the two crossing members are connected according to DIN 4114 Part 2/02.53, _;Ri 6.41. For bracing members which in the plane of the are supported tovrer face by a redundant bracing at ·1 east at third points and which are restrained at their crossing point by a reinforcing panel arranged not in the plane of the face, the reduced buckling length sk = 0,9 s may be assumed for buckling r e c t _an g u 1 a r 1 y to the plane of the face. ,for the
a K-bracing, '.. sk '= 0,9 s may only be adopted if the ends of bracihg .members are supported by a reinforcing panel.
.
"
·.;
:,~·
/•
~· C;·-~
~-~-2.12
..:!
:
~~~es r.: :-....~· , ,..
In all other
sk
=
s shall be taken.
Proof of local b~ckling strength
Depending ron ·the ratio ~f ihe angle width b to angle thickness t the following conditions exist with respect to the necessity to prove the local buckling strength of the angle section. b/t ~ 15 15 ~ b/t ~ 20 b/t > 20
no proof necessary proof necessary, if b/t proof necessary,
>
0,2
A
where 'A means the slenderness ratio relevant to the rating of the member. 8.4.2.13 Structural components embedded in the ground Clause 9.5.3 shall be met when rating structural components which are embedded in the ground.
DIN VDE 0210 Paae
"'
37
8_4.3 Basic principles for design and manufacturing 8_4.3.1 Minimum dimensions of components thi~kness of components shall generally not be less than mm. In case of hollow sections used for towers the thickness m~y be reduced to 3 mm if effective protection against ccrrosion is ensured according to the requirements or D:N 18800 Part 1 together with DIN 18801 and DIN 18808 on the i~ner and outer faces. T~e
4
If weakened by boltholes, angle sections with a width below 35 mm ar-d flat bars with a width below 30 mm are inadmissible for all t T?e s of members , as we 11 as r i v e t s wi t h a fin i she d d i am e t e r less than 13 mm. • I·
.....
.·· \~··
Diameters
of bolts less than 12 mm are not permissible for loading. The minimum strength quality for bolts M 12 is 5.6 according to DIN 267 Part 1.
st~uctural
8.~.3.2
Dimensions of connecting elements in joints
The maximum permissible ·diameter of a driven rivet and the maximum permissible diameter of threads of mechanically loaded bolts and the diameters of related boltholes are determined by the width of the angle legs and may be taken from Table 10 together with the edge distances in direction of the force. The .minimum dist~~~~s between centres of boltholes shall be not less than 2,5 times the diameter of the holes, the edge distances rectangularly· to the direction of the force shall be not less than 1,2 ti~es of the diameter of the bolthole. ·.
..,
.···./·......:
'
•:\
.·
..
8.4.3.3 E6centricity ~f member connections • . .. .. ., . ! ~.
-~
The, ,eccentricity of the connections of members at nopes shall be ke.pt . . a:s··•. -small \i.s pass ible. · • . .... ·.. ".( •.. : ;'t ·... • ~-
·: ••• ;,;
';•t. i~ T"'! i···. ~
n. .~ ;:
r·
8.4 .• 3·~--C~mpound compression members ..• .. ...... _
t
J
(.
•
In case of compound compression members the slenderness ratio of a sub-member shall not exceed 50. If stay plates are adopted they shall be arranged at least at third points of the total buckling length and at the ends of the members. If members comprising two angle sections are connected to a common gusset plate, separate stay plates at the member ends are not necessary. Every stay plate shall be connected to each sub-member by means of two rivets or equivalent bolts or of an equivalent welded seam designed accordibg to the relevant standards. At the ends of the members one additional connecting element shall be provided for each of these connections. Compound compression members with bracings shall also be provided with stay plates at the ends of the members.
Page 38 DIN VDE 0210 Table 10. Dimensions of connections and edge distances of jointing components in mm M 12 M 16 M 201M 24 M 27 M 30
Dimension of bolts Max. diameter of bolthole
Hexagon bolts Rivets
14 13
I
I
18 17
22 21
26 25
29 28
32 31
Min. width of angle leg
35
50
60
70
75
80
Min. edge distances of the force
20 25
25 35
30 40
40 50
45 55
50 65
in direction
The ---minimum va 1 ue s of the specified edge distances in direction of the force which are measured from the centre of the hole shall be ·"ad h e r e d to in any case. For tensile loaded components of the vertical truss well as for leg faces of cross arms as member joints the higher values shall be adhered to.
.
8.4.3.5 Securing of bolted connections Nuts of bolts should be secured against
loos_~\uing
.
/
.
8.4.3.6 Punching of holes for rivets and bolts Holes_ for rivets and bolts may be punched into angles and plates of up to -12 mm thickness. Permanent supervision shall ensure that sharp punches and suiting ~ies are used for the manufacturing. Structural /members . of shall not ~e punched. '.'
·::
-.
; / _-,_-
'
crossarms permanently loaded in tension
-
8.~.3~7-~~i~~ays f~r climbing the towers '
·;·~·..... '
4
.•• "
•'
Latt1c~~~~~~~l towers need no special walkways for climbing and access: to working positions if the distance between nodes at the leg membe~_~6~s not e~ceed 0,45 m or if the structural members of the tower "which have to be used when climbing are not inclined by more t'han 30. 'and the distance between any standing position and the next structural component a.bove does not exceed 1,7 m or if climbing devices independent of the tower such as ladders or elevating platforms are to be used. In case of lattice steel towers which do not comply with these stipulations separate climbing facilities shall be arranged on at least, two diagonally opposite leg members. In the case of a two line step bolt arrangement the angle between the planes of the bolts shall be at least go•. The width of the steps shall amount to at least 300 mm for single line arrangement and at least 150 mm in case of two line step bolt arrangement. Flat tread width shall be at least 20 mm, and the diameter of cylindrical treads at least 24 mm. To provide a protection against sliding a lateral limit at least 20 mm high measured from the top of step must be provided.
DIN VDE 0210 Page 39 Step bolts shall be rated for a concentrated load of 1500 N acting vertically at a structurally unfavourable position. The permissible stresses for exceptional loadings apply in this case. Normally the step bolts should be arranged with a constant distance of ~ 333 mm. If due to the design of the tower the distances between alternate steps can not be equal and/or can not be 333 mm or less, two adjacent steps may vary by up to 100 mm but the spacing between steps shall not exceed 403 mm. In the vicinity of the crossarm joints structural components may be used as treads instead of step bolts. 8.5 Poles made of solid wall profiles 8.5.1 General specifications This clause applies to polygonal cross-sections.
solid
wall
poles
with
circular
or
Solid wall steel poles can be allied to structures predominantly subjected to static loadings. As far as materials, permissible stresses, use of high-strength bolts, welded joints and thickness of materials are concerned, the requirements for lattice steel towers apply accordingly. 8.5.2 Analysis and design 8.5.2.1 Evaluation of internal forces and moments The evaluation of the internal forces and moments shall be carried out according to the second order theory. If this more precise proof is not undertaken the effects of second order theory may be considered by the following additions to the moments which have been determined according to the first order theory: Suspension, angle suspension and angle towers section towers, angle section towers, terminal towers
5
%
3 %.
This applies to poles having a length up to 40 m between of the foundation and the top of the uppermost crossarm.
~he
top
8.5.2.2 Stability against local buckling A more precise proof of the stability against local buckling may be dispensed with in the case of polygonal cross-section structures with a maximum of 12 sides if the following condition applies: s :5. f.:.
t
where: s theoretical width of sides of the polygon t thickness · ·
·page 40 DIN VDE 0210 . k
= =
43 for St 37-2 and 35 for St 52-3.
8.5.2.3 Limitation of deflection The latteral deflection of the pole at the pole top due to the load may theoretically be demonstrated following the first order theory without consideration of the movement of foundation and shall be limited as follows: Suspension and angle suspension poles: 4 % of the length of poles when loading cases MN 2 or MN 5 of Table 7.
being loaded according to
Angle poles, section poles and terminal poles: 2,5 % of the length -bf poles when being loaded according to loading case MN 1 of Table 7. 8.5.2.4 Cut outs If the effective cross-section is reduced by cut outs for doors, etc. a statical analysis shall be carried out on the basis of the effectively available cross-section. 8.5.2.5 Overlap joints Joints in the bodies of solid wall poles with circular or polygonal sections may be made by lapping without adoption of connecting elements and without an analytical proof if the following conditions are simultaneously fulfilled: Length of overlap is greater than 1,5 d m "1-Ihere: d corresponds to the outside diameter at the end of that tube m which is outside. In the case of polygonal poles d means the mean value of the diameters of the enveloping aWd the fitted circles of the cross-section at the end of the tube on the outside. Pole taper
:: 10 mm/m
Thickness of wall
::: 16 mm.
8.6 Reinforced concrete poles Reinforced concrete poles and their crossarms shall be designed on the basis of the load assumptions according to Clauses 8.1 to 8.3 and rated according to the current DIN standards. 8.7 Wood poles 8.7.1 General specifications The standards DIN 48350 and DIN 48351 Part 1 and 2 single wood poles and A-poles, respectively.
apply to
DIN VDE 0210 Page 41 8.7.2 Analysis and permissible stresses If sing:~ wood poles and A-poles do not comply with DIN 48350 and DIN 48351 Part 1 and 2, respectively, a analytical proof will be necessar;. The stresses given in Table 11 shall not be exceeded. Table
1:. Permissible stresses for wood poles and sleepers
Type of loading
Coniferous timber N/mm 2
--
Hard wood N/mm 2
I
Tension or bending
14 '5
Compre.:;:.>ion in direction of fibres
11,0
12,0
Compres:; ion transverse to direction of fibres
3,5
5,0
Shearing in direction of fibres
1' 8
2,0
Shearir,g transverse to direction of fibres
3,0
4 '0
A bending and of 80 timber.
19,0
of strength 50 N/mm 2 in case of coniferous timber 2 N I mm in case of hard wood shall be assumed for round
For sawn wood, with the exception of sleepers, the permissible stresse.:;, according to DIN 1052 Part 1 shall be adhered to. In case of dowelled double poles the section modulus may be taken as three tlmes the section modulus of the single pole if the lead acts in a plane which is determined by the axes of both poles. All oth0r types of double poles shall be treated as poles.
t~o
separate
8.7.3 Principles for design and manufacturing If wood poles are in use for more than three years they shall be protected effectively by preservative agents against rotting and insects. Particular attention shall be given to bore holes and scarfing::;. Even if bore holes and scarfings are made subsequently they shall be provided with an efficient wood protection. Dowelled double poles shall be provided over their total length with 4 to 6 dowels and bolted together. Dowelling will be effective only if the spacers are either fitted into the poles or if they penetrate into the wood poles by teeth or claws such that the pole::; can be considered as rigidly connected.
Page 42 DIN VDE 0210
8.8
Poles made of other materials
For other tower designs and for towers made of other materials the same minimum requirements accordingly apply as in case of the above mentioned tower types. Towers made of aluminium alloys shall be designed according to DIN 4113 under consideration of the loading assumptions specified above. For normal loading according to Clauses 8.1 to 8.3 the permissible stresses valid for the loading case H (main forces) apply, and for exceptional loading 1,375 times these stresses.
8.9 Stays for towers Galvanized steel ropes according to DIN 3051 Part 4 (round-shaped flexible stranded ropes with steel core only) and DIN 48201 P a r t 3 s h a ll b e ---us e d a s s t a y wi r e s . Ro p e s wi t h t h i c k l y g a l v a n i z e d strands should be used preferably (see Appendix A). Steel ropes with any other type of corrosion protection may be used if that protection is at least as effective as the specified galvanizing. The failing load of the steel ropes with end fittings included shall be at least 2,25 times or 1,8 times the working force for normal and excertional loading, respectively. Th8 failing load of the rope provided with end fittings shall be demonstrated by tensile tests on at least one sample per rope diameter. This requirement for tests can be disregarded - if the design of the rope and of the end fitting as well as the corresponding mechanical strength data can be taken from a DIN standard or - if the proof has already designs and dimensions.
been
carried out
for comparable
Stays shall be equipped with devices for retightening. The connection of the stay ropes with the anchor device shall be accessible. The jointing elements shall be secured against unintentional loosening. Stays of wood poles and poles made of materials with insulating characteristics shall be additionally equipped beyond arm reach Hith an insulator designed for adequate mechanical and electrical strength (see DIN VDE 0141). For all other towers the stays shall be bonded to the earthing system of the support.
8.10 Protection of birds Crossarms, insulator pins and other components of overhead power lines shall be designed to preclude a resting perch for birds within a dangerous proximity to live conductors.
DIN VDE 0210 Page 43
g. FOUNDATIONS The foundation of a tower can be designed either as a compact foundation or as a separate footing foundation. Compact foundations are characterized in that the tower body is accomodated by one foundation and, in addition to horizontal and vertical for~es, essentially bending moments occur as loadings. Depending on the type of the compact foundation, the transfer of the structural loads is achieved by soil pressures within the foundation subface and by lateral soil resistance. Separate footing foundations are characterized in that individual foundations for each leg member of the tower are provided and each of these receives -€~sentially vertical loads in addition to horizontal loads. "Uplift loads are counteracted by the deadweight force of the foundation body, by an earth surcharge perhaps available and/or by shearing forces within the soil. 9.1 Requirements The foundations of towers shall be capable of transferring the structural loads resulting from the loading cases according to Clause 8.2 inLo the given subsoil with sufficient reliability. This objective can be achieved by design and construction of foundations according to Clauses 9.4 to 9~8. For poles the stability of which, according to experience, is ensured without a specific foundation body a proof may be disregarded. The stability of foundations may also be proved by loading tests. 9.2 Types of subsoil Due to its varying performance in case of loading by foundations the subsoil is subdivided into natural soil (loose ground), rock (solid ground) and made up ground. 9.2.1 Natural soil A soil is called natural if it is the result of a decayed geological procedure. Following main types have to be distinguished. 9.2.1.1 Non-cohesive soils Sand, gravel, boulders and their mixtures are classified as noncohesive soils if the weight portion of ingredients with particle sizes less than 0,06 mm does not exceed 15 %. The coarse grained soils (GE, GW, GI, SE, SW, SI) and the mixed grained soils (GU, GT, SU) according to DIN 18196 are within this category. 9.2.1.2 Cohesive soils Clays, clayey silts and silts as well as their mixtures with noncohesive soils (mixed grained soils with higher portion of finegrain) are classified as cohesive soils, if the weight portion of cohesive ingredients with particle sizes below 0,06 mm exceeds 15% (for example sandy clay, sandy silt, loam, marl). The fine
Page 44 DIN VDE 0210 gr~ined
solls iUL, UM, TL, TM, TA) and the mixed grained soils (SU, ST, ST, GU and GT) according to DIN 18196 are within this category of soil.
9.2.1.3 Organic soils and soils with organic ingredients Peat or mud and anorganic soils according to the Clauses 9.2.1.1 and 9.2.1.2 with organic ingredients of animal or vegetable origin are called organic soils and soils with organic ingredients, respectively, if the weight portion of organic ingredients exceeds 3 % in case of non-cohesive soils and 5 % in case of coheesive soils (for example arable sand, mud or peaty sand, organic silt or clay, marl). The organogenic and organic soils, respectively, according to DIN 18196 correspond to these types of soils.
9.2.2 Rock Throughout this standard all solid grounds are identified by the generic term "rock".
9.2.3 Made up ground and fill Made up ground or fill may originate from mechanical dumping or water borne extr2~tion. It is necessary to identify: Uncompacted fills of any composition and, if the fill has been sufficiently compacted, compacted fills of non-cohesive or cohesive types of soils and of anorganic filling products (for example construction waste, scorea, ore tailings).
9.3 Soil investigations and soil characteristics 9.3.1 Soil investigations Prior to determination of the type of foundation, of its depth and dimensions, the structure of soil below the envisaged botto~ of foundation, and in the case of a piled foundation below the pile point, must be known in sufficient detail. The soil investigations shall be carried out to such a depth that all layers which significantly influence the foundation strength are included. When determining the extent and depth of soil investigations, information already available concerning the pattern, uniformity and characteristics of the individual layers can be taken into consideration. Where justified, further soil investigation can be omitted. Type, condition, extent, stratification and depth of the soil layers as well as ground-water conditions can be suitably examined by boring, sounding or trial pits, if available knowledge does not provide sufficient information. The results of soil investigations shall be recorded, viz. for boring in accordance with DIN 4022 Part l and for soundings in accordance with DIN 4094 Part l and Part 2.
DIN VDE 0210 Page 45 9.3.2 Soil characteristics If the soil investigations do not yield other values the soil characteristics according to Table.l2 assigned to the recorded soil conditions shall be assumed when rating the foundations. Sufficient compaction of the backfill shall be ensured when adopting these values. In certain circumstances a possible reduction of consistency of cohesive soils and hence a reduction of load carrying capacity shall be allowed for. The permissible soil pressures given in Table 12 apply to a depth of not more than 1,5 m and to a width of the foundation base of more than l m. If the depth of embedment is more than 1,5 mat a 11 s i de s of t he f o u n d a t i o n b o d y t h e ---P e r mi s s i b l e so i 1 p r e s s u r e may be increased by the value which results from the surcharge of the soil associated with the additional depth multiplied by the factor K (see Table 12). In case of ground-water the reduction of strength capacity of the foundation shall be considered taking care of the most unfavourable ground-water table. 9.3.2.1 Methods to identify soil types DIN 4021 types.
and
DIN
4022
Part 1 apply to identification of soil
9.3.2.2 Methods to identify the soil condition The condition of a cohesive soil can be determined by field test as follows: A soil is very soft squeezed in the fist.
if it exudes between the
fingers Hhen
A soil is soft if it is easily moulded in fingers. A soil is firm if it can be moulded by strong pressure in fingers, and rolls of 3 mm diameter can be made without breaking or crumbling. A soil is stiff if it breaks ·or crumbles while attempting to prepare rolls of 3 mm diameter, however, it would contain sufficient moisture to re-form a clod of earth. A soil is hard if it is completely dried and appears lightcoloured in most cases. It can not be moulded further but would break. After crumbling it cannot be re-rolled. The compactness of non-cohesive soils can be determined according to DIN 4094 Part 1 and Part 2. 9.4 Basis of design 9.4.1 Loading cases and stability requirements for foundations In Clause 8.2 a distinction is made between normal and exceptional loadings in respect of loading cases to be adopted for the
Table 12. Soil characteristics for design of foundation 1
2 j3 Specific weight force(values for design)
1----------- ----------- --· Type of soi 1
na turallyl with humid bouyancy
_II ____
>-o
I;,__,-~-~-------
Angle oftliP~1n;';'"'soll internal pressure friction at a depth not more than 1,5 m
7 8 ____ -~ Jll Angle of earth frustum ace. to Clauses
1_9
Coeff. K ace. tol9.6.1,. 9.6.2 and 9.6.3 (B 0 ) 9.5.1 (B) Clause 9.3.2 Foundation type acc.to Fig.~
u
B
IJ\
1----'-
kN/m
3
kN/m
3
Degree
Undisturbed soil ace. to Cl. 9. 2.1 Non-cohesive soils ace. to Cl. 9.2.1.1 Sand, loose Sand, semi-dense Sand, dense Gravel, bolder, uniform Gravel-sand, graded Bolder, stones, macadam, graded Cohesive soils ace. to Cl. 9.2.1.2 very soft soft (easy to kneed), purely cohesive soft, with non-cohesive additions firm (difficult to kneed), purely cohesive firm, with non-cohesive additions stiff, purely cohesive stiff, with non-cohesive additions
kN/m
3
-J
----1
17 18 19 l7 18 I
18
9 10 ll
9 10
30 32,5 35 35 35
200 300 !JOO
400 !JOO
I
I
5 5 5
liQO 10 ~---·1 - - -1---------1---·----35
16
8
0
0
18
9
15
IJO
2
19
10
l7' 5
!JO
18
9
17,5
19
18
10 10
19
ll
l
Mono block
l6tol8 l8to20 20to22 20to22 20to22
5tol0 5tol0 8tol0 8tol2 8tol2
___J___ I25 to 3~j33to2 ~J20 to2~
8tol2
38to4 9 22to27 ~lto53 25to30 4lto53 25to30 ~lto53 25to30
l8to2l 20to23 22to25 22to25 22to25
0
I0
0
9tolll 6to 8
~~
2,5
lltol31 8tol0
lj
100
2,5
2lto27116tol9llltol5l Stoll
6
22,5 22,5
100 200
3 3
26to34,18to2l/l3tol7110tol3 26to34 22to26 15to23 lltol9
6 8
25
200
3,5
29to38l25to30ll7to26ll3to21
8
CD
-'=
H
z c::::1 0 t:>l 0 N 1-' 0
I
+--------
f
(1::1
"'t'
Degree
-1
3,5 11
s
Pl
-=". . . ·
.,;;"
hard, purely cohesive hard, with non-cohesive additions Organic soils and soils with organic additions ace. to Cl. 9. 2 .1. 3 Rock ace. to Cl. 9.2.2 with considerable fissuring or unfavourable stratification in sound, not decomposed condition with minor fissuring or favourable strati'fication
18 19
400 400
27,5 30
3,5 4
I
32to42 30to37 23to28 13to23 10 35to46 33to40 26to28 2lto23 10
t
5tol6
Oto 7
15
1
0
0
i l
' '
20
independent of depth up to 1000
25
up to 3000
\
Made up ground and fill ace. to Cl. 9.2.3 (depending on condition and thickness of foundation strata as well as compactness and uniformity of their stratification Uncompacted embankment
12tol6
Compacted embankment
Classification ace. to type of soil, density 0f stratification and consistency, resp.
6tol0
l0to25
30tol00
2
6tol3 --
I.JtolO 0 H
:z: < 0 trl
0 N 1-J
0
., PJ (JQ (D
.t= ---.j
Page 48 DIN VDE
02~0
individual tower types. The foundations of the towers shall also be rated for both loading conditions. The stability conditions and the permissible stresses mentioned in the following clauses apply to normal loading. In the case of exceptional loading the values applying to the normal loading may be adopted, however the loads acting on the foundation in an exceptional loading case' may be reduced by multiplying with the factor 0,8. 9.4.2 Unit weight of concrete For the purposes of analysis, the maximum unit weight of the nonreinforced concrete may be taken as 22 kN/m 3 , and of reinforced 3 concrete as 24 kN/m • 9.4.3 Frost-proof bedding of the foundation subface The foundation subface which has to transfer vertical loads to the subsoil shall be bedded at a frost-proof depth, but at least 0,8 m below ground level. 9-5 Compact foundations 9.5.1 Monob1ock foundations Monoblock foundations can be designed with or without a step. 9.5.1.1 Assumptions for design When designing monoblock foundations the loadings resulting from external loads according to Clause 8.2 as well as the dead load of the foundation and the vertical. surcharge due to soil resting upon the foundation base shall be taken into account. Additionally the dead load of an earth frustum, the limiting faces of which start at all sides at the lower edges of the foundation base and are inclined at an angle 8 outwards f~om the vertical may be considered. The magnitude of the angle B depends above all on the angle of internal friction as well as on ' the consistency of cohesive soils, on the compaction of soils and on the adhesion and bond between foundation block and the soil (For standard values see Table 12). When rating monoblock foundations th~ lateral resistance of soil may be taken into account a~cording to the compaction and characteristics of the soil. It is essential therefore that the soil will be neither permanently nor temporarily removed as long as the external loads apply. 9.5.1.2 Stability conditions The inclination of the foundation body under load shall not exceed 1 %. If the resisting moment due to lateral soil pressure exceeds the resisting moment due to the pressure in the foundation subface the theoretical proof of a stability of 1,0 will be sufficient. The decreasing proportion of the lateral soil resistance on the total carrying capacity of the foundation necessitates a progressive increase in stability requirement which must achieve 1,5 when the lateral soil resistance falls to zero.
DIN VDE 0210 Page 49 The soil pressure shall be proved. If no other values result from the soil investigations the permissible soil pressures may be taken from. Table 12. 9.5.2 Slab foundations 9.5.2.1 Assumptions for design If the body of a tower is supported by a foundation block formed by a slab whereby the lateral restraint of the soil can be neglected the loadings according to Clause 8.2 as well as the dead load of the foundation block and the vertical surcharge of the soil resting upon the foundation block shall be taken into account. 9.5.2.2 Stability-conditions The stability against tilting shall be at least 1,5. This requirement is met if the gap under the foundation subface does not extend beyond the centre of gravity of the base area. This condition is satisfied if the eccentricities e and e of the resulting total vertical load in the foundationxsubfac¥ fulfil the following conditions: For rectangular subfaces (see Fig. 3):
For circular subfaces:
t~;:; r
0.59
where, r radius of the circular area.
-
X
b.
3
Fig. 3. Area of the foundation subface permissible for the position e , e of the force N resulting from total vertical load. x Y In addition to stability against tilting, the soil pressure shall be proved. If the soil- investigations do not provide other values the permissible soil pressures may be taken from Table 12.
Page 50 DIN VDE 0210 In case of rectangular theoretical soil pressure
slabs
it
shall
be
shown
that
the
does not exceed the permissible soil pressure. In case of circularly shaped slabs it shall be shown that the maximum theoretical soil pressure divided by the factor 1,3 does not exceed the permissible soil pressure. 9.5.3 Raft-type slab foundations If a raft-type foundation is designed such that all leg members are connected by one raft made of sleepers then the calculation may be carried out according to Clause 9.5.2. In this case the gross area of the raft may be taken into account if the intermediate space between the sleepers does not exceed 1/3 of the width of the sleepers. Members of the tower embedded in earth ar.d inclined by more than 15• from the vertical shall be assumed as additionally loaded by the earth resting upon them. The additional load to be assumed shall at least correspond to the load of a prismatic earth body of three times the member width and with vertical faces. The compaction tiously.
of
the
backfill
must be carried out conscien-
9.5.4 Single pile foundations If the body of a pole is provided with a foundation body consisting of a single pile with loadings according. to Clause 8.2 the dead load of the foundation as well as the lateral restraint of the pile according to the compactness or consistency and to the characteristics of the soil shall be taken into account when rating the foundation. The loadings to be assumed are transferred to the subsoil essentially by lateral soil resistance. The performance of the subsoil as well as the displacement of the pile in a horizontal direction shall be considered. The analysis of a single pile foundation shall be carried out according to an accepted method. 9.5.5 Foundations of wood poles If in case of good bearing subsoil the depth of planting of single or double poles is at least 1/6 of the total lengths, but not less than 1,6 m, a proof of stability may be waived. Direct concreting of .wood poles is not permissible. DIN 48351 Part 1 and Supplement 1 to DIN 48351 apply to the foundation of A-type poles.
DIN VDE 0210 Page 51 9.6 Separate footing foundations 9.6.1 Stepped block foundations 9.6.1.1 Assumptions for design As far as the method of installation and the performance under loading are concerned the stepped block foundations (Fig. 4) are classified as: Foundation type U: Lowermost step undercut. Foundation type A: Lowermost step concreted to undisturbed subsoil. Foundation type S: Lowermost step concreted to shuttering. If the base slab projects on all sides by at least 20 em then, in addition to the dead load of the foundation block to act against the uplift force, the dead load of earth enclosed by the angle B of earth frustum accordirg to Fig. 4 may be taken into account. The angle 8 may be calculated according to the formula
Hhere: b
n I.Jo
angle of earth frustum for -t Table 12 Columns 8, 9 and 10.
b
width of the lowermost step see Fig. 4. In the case of foundations with circular subface the diameter of the base shall be inserted for the width. In the case of a rectangular subface the geometric mean b =~b 1 . b 2 shall be assumed as theoretical width.
= 1
according to
when b !b ~ 1,4 where b is the larger width. 1 2 1 depth of earth frustum, see Fig: 4.
This applies, t
The method explained above only applies to those stepped concrete foundations the ratio b/t of which is more than 0,25 for foundation type U and more than 0,6 for foundation types A and S. If b/t exceeds the value 1, then 8 = 8 shall be assumed for calculation. The angle of earth frustum B0 shall be limited to 35·.
0o
As a rule, the val~es mentioned in Table 12 Columns 8, 9 and 10, apply to widths of the foundations between 1,5 m and 5,0 m in case of foundation types U, A and S. Within the ranges assigned to the individual types of soil the lower values of shall be taken together with large foundation widths and the upper values of with small foundat.ion widths. Values in bet•..Jeen may be linearly interpolated.
0o
0o
Page 52 DIN VDE 0210 Stepped concrete foundation Foundation type U "undercut"
Foundation type A "concreted to undisturbed soil"
Foundation type S "concreted to shuttering"
leg member
leg member
leg member
"-.../
"--!
"--! ·-r--"1
,-· -..!.
·--*-'------'--!./
: :2::0,2 m ,
'
~--.,.---+,_-:.·=---r--t
_..____ :e::s0,15b
e~0.1Sb
'·
'-'
;
i
.A. '
~1.._:
t
I,
·T :-----,
.
b
£1
... 17 ';' . ...... .._ .._ .....II
b
c
=
~2 however
i
;-----,
Auger-bored and excavated foundation Foundation type B leg member "-...' .I ·.
Separate grillage foundation as in case of typeS)
(0
leg member ___
----
.
'
i
'
:2::0,2m
bresp.d
Where: =angle of earth frustum ace.
to Clauses 9.6.1.1·,
9.6.2.1
and 9.6.3.1 e
=
permissible eccentricity ace. to Clause 9.6.1.4
natural soil backfill Fig. 4. Assumptions for design of stepped concrete foundations, auger-bored and excavated foundations as well as separate grillage foundations
DIN VDE 0210 Page 53
9.6.1.2 Stability conditions in case of loading by compression In case of stepped block foundations loaded by compression it shall be proved, that the soil pressures which are assumed to be equally distributed over the foundation subface do not exceed the permissible soil pressures according to Table 12. The dead load of the soil resting vertically upon the foundation base shall be considered as a surcharge. The eftect of a horizontal load on the soil pressure may be neglected compared with the prevailing effect of the vertical load.
9.6.1.3 Stability conditions in case of loading by uplift In case of s t e p p e d b 1 o c k foundations u n d e-f- an up l i f t l o ad a s t ability of 1,5 against being pulled out shall be proved. For loads which, according to Table 7, result from - loading cases MN 1 and MN 2 for angle suspen~ion towers and angle towers and - loading cases MN 1 and MN 2 for section towers and - loading cases MN 1 and MN 3 for terminal towers the stipulated stability shall be increased by 10 %.
9.6.1.4 Additional conditions In addition to the stipulated stability it shall be proved that the following condition is met: For foundation type A: G/Z > 0,67 For foundation type S: G/Z > 0,80 Hhere: G
dead load of the foundation block and of the soil resting vertically upcn the foundation base.
z
Vertical dation.
component
of
the
uplift force acting on the faun-
The ultimate capacity of foundations against uplift is essentially governed by the compactness and the consistency of the surrounding subsoil. The benefitial results of an intensive artificial compaction of the surrouna1ng subsoil (compaction by vibration process or similar methods) may be taken into account. The virtual ·point of penetration of the leg member through the foundation subface may deviate from the centre of the foundation subface at maximum by the amount specified in Fig. 4.
9.6.2 Auger bored and excavated foundations 9.6.2.1 Assumptions for design Auger bored and excavated foundations (foundation type B according to Fig. 4) are column-type foundations made of reinforced concrete with expanded bases. As a rule, they not only carry the loads and moments acting at the top of the foundation axially but also transfer the loads resulting from horizontal forces and bending moments by lateral bearing of the shaft on to the subsoil.
Page 54 DIN VDE 0210 The
angle
of earth frustum
0
may be evaluated using the formula
Where:
0o b t
angle of earth frustum for b = l according to Table 12 t umn 7 width of foundation, see Fig. 4 depth of foundation, see Fig. 4
Col-
The angle of earth frustum shall be limited to 35". The soil characteristics may be taken from Table 12. As a rule, the values given in Table 12 Column 7, for foundation type B apply to foundation widths between 1,2 m and 2,1 m. Within the ranges mentioned for the individual types of soil the lower values of apply to large foundation widths, and the upper values of to small foundation widths. Values in between m".y be interpolated linearly.
0o
0o 0o
In case of auger bored and excavated foundations the transfer of the horizontal forces to the subsoil (lateral bearing), as well as of the bending loading have be proved by an accepted method. 9.6.2.2 Stability conditions in case of loading by compression In case of foundations loaded by compression it shall be proved that the soil pressures, which may be assumed to be equally distributed within the foundation subface, do not exceed the permissible soil pressures according to Table 12. The deadload of the foundation body as well as the deadload of the soil resting vertically above the foundation subface shall be taken into account. 9.6.2.3 Stability conditions in case of loading by uplift In case of foundations loaded by uplift a stability of 1,5 against being pulled out shall be proved. The analytical proof of stability may be carried out using the earth frustum method. Thereby, additionally to the load of the foundation body counteracting the uplift, the deadload of a soil body formed by an angle of frustum applied to the edge of the foundation subface can be taken into consideration (see Fig. 4).
0
For loads which, according to Table 7, result from loading cases MN 1 and MN 2 in case of angle suspension and angle towers, loading cases MN 1 and MN 2 in case of section towers loading cases MN 1 and MN-3 in case of terminal towers the stipulated stability shall be increased by 10 %.
DIN VDE 0210 ?age 55
9.6.2.4 Additional conditions The for~ula for the deter~ination of the angle of earth frustum 8 is validated for foundations with dimensions complying with the follo~ing boundary conditions: - De~th of foundation between 1,8 and 7,0 m. - Diameter of column between 0,7 and 1,5 m. -Width of foundation between 1,2 and 2,1 m. - Projection of foundation subface equal or more than 0,2 m. - Ratio of foundation width to foundation depth (b/t) between 0,25 and 0,7. With regard to construction the ratio of the projection of foundation subface to the height of the foundation base should be about 0,5 in case of cohesive soils, and about 0,33 in case of non-cohesive soils.
9.6.3 Separate ·grillage foundations 9.6.3.1 Assumptions for design T'1e des1gn or the separate grillage foundations m3y be carried out using the earth frustum method according to Clause 9.6.1.1. Th0 angle of earth frustum complies with that of stepped block foundations, type S. Clause 9.5.3 applies to the rating of tower members embedded in the subsoil.
9.6.3.2 Stability conditions in case of loading by compression In case of separate grillage foundations loaded by compression a proof according to Clause 9.6.1.2 shall be carried out. The total area of the foundation subface may be taken into account, if ~he spacing between the individual sleepers docs not exceed l/3 of the width of the sleepers.
9.6.3.3 Stability conditions in case of loading by uplift In C3se of separate grillage foundations loaded by uplift a stability of 1,8 against being pulled out shall be proved. according to Table 7, result from
:or :cads which,
:c2ding cases MN land angle towers,
M~
2
in case of angle suspension
~~c
cas e s 1·1 ~l l and t·HI 2 in case o f sect ion to'" e r s and
: c au i :-: g
cases
M~
1 and MN 3 in case of terminal towers
the stipulated stability shall be
9.6.4 Pile
foundation~
G~:1eral
9.6.4.1
P;
~ ·) ~ : :.. :"'. ~.:: :~e
!'"" ~ !:
c~ designed such that the foundations shall !'rem the structure are exclusively transferre~ by the piles.
-
1 A
~-
:J
increased by 10 %.
u l t : :-: ~
3u~scil
Page 56 DIN VDE 0210 Significant horizontal components of loads may be counteracted, by a bending resistant design of the piles in addition to a battered arrangement of the piles (raked piles, pile groups). Fo~ndation
piles should be loaded essentially in direction of axes. The transfer of the loading from the structure into the piles shall be proved. Floating-pile foundations should be avoided as far as possible. They may be adopted if the resilient layers at increasing depths are progressively more solid i.e. less compressible, so that lesser settlements would occu: than in the case of a wide shallow foundation. th~i:
Within a separated foundation, for the same static function (for example, transfer of uplift or compression forces) piles shall be used which by their method of installation, their arrangement and their materials provide approximately the same performance in respect of deformation and settlement. If over an extended area a loading (for example due to a fill) acts upon a soft layer of soil above good bearing subsoil in the vicinity o:' a pile foundation, horizontal mo,·c·ments of the so:'t soil can occur. The piles, will then be additionally loaded by bending. Th~
theoretical pile working loads result from the loads to Clause 8.2. When rating the piles the effects of buoyancy and other· effects which reduce the stability shall be considered. In case of foundations loaded by compres~ion the releasing effect of buoyancy may not be taken into account. accordi~g
9.6.4.2 Minimum length of piles piles shall be installed with a minimum length of 6 m and sh,1ll be embedded at least 3m into the good bearing soil unless their stability is demonstrated by loading tests.
Th~
9.6.4.3 Arrangement of piles Parallel as well as raked piles shall be provided with sufficient spacing between their axes such that neither during installation nor after loading adverse reactions can occur on adjacent piles (see DIN 4014 Part 1 and DIN 4026). This requirement is met if the distance of the pile axes at the pile end in the soil reaches at l~ast three times the maximum cross-sectional dimension of the pi 1 c. 9.6.4.4 Strength capacity of piles The
strength capacity of a pile depends on the structure of the and its properties, on the groundwater conditions, on the d~p~h of penetration into bearing soil layers and on their thickne~~. on the shape of the pile end its cross-sectional area, on th~ ~a~er:al of the pile, on the nature of the circumferential su:--~ace a:1d on design of the pile point, on the arrangement of ~h~ ~ile a~c on the distance of piles as well as on the installati0~ procedure. Additionally the thickness and the streng~h of ·: :. ·: ., ': '~ r d-= :-: so i l 1 a y e r s are s i g n i fica n t . More over , the e f f e c t s 0 : a~~:ng, o: negative skin friction and of lateral superimposed :a~~:ng shall be considered. ~ut~oil
DIN VDE 0210 Page 57 The strength capacity of driven piles the skin friction of ~hich provides an essential portion of their total capacity may even increase over longer periods after driving especially in finesandy, silty and clayey soils. A co~pression pile may be loaded additionally by negative skin friction if the upper layers of soil settle. The effect of n~gative skin friction on the structure can be reduced by a suitable design of piles and by choice of larger spacing bet~een piles. In case of uplift loaded piles the releasing effect may not be considered. The strength sur.:rnation of
capacity of pile groups may be determined by the strength capacities of the individual piles.
9.6.4.5 Assumptions for design and stability conditions The piles skin the
theoretical determination of the ultimate tensile load of may be carried out by means of skin friction. The values of friction must be deduced for the given soil conditions and selected type of pile based on experience with the partic~lar type of soil. As an approximation, in case of layers of soil with varying values of skin friction, the friction forces ~ay be determined separately for each individual layer and the ultimate tensile load m.::>y be calculated by summating the individual values. For this, the thicknesses of the layers and ~equence of layer~ as well as the groundwater table shall be considered. Since for piles a wide scatter of the values of skin friction has to be expected the theoretical proof of stability of a pile under uplift loading shall be carried out for a stability factor of 2 against reaching the ultimate tensile load Q . When carrying out the proof by loading tests according to Clau§e 9.6.4.6 a stability factor of 1,5 will be sufficient. The ultimate load is reached ~hen an uplift-tested pile is lifted perceptibly or a compression-tested pile settles down perceptibly. On the tension-versus-displacement curve or on the co~pres sion-versus-settlement curve, the ultimate capacity is determined by the point where the flat gradient, after a range of loading resulting in progressively increasing displacements or settlements, passes into the steeply sloping leg. For loads o.,rhich, according to Table 7, result from loading cas~s angle to•,1ers,
t1N
1 and MN
2 in case of
suspension angle and
loadi:;g cases t111 l and t~N 2 in case of section towers and - l0ading ca.ses i1N 2 and Mtl 3 in case of ter~inal towers tr.e requirec stability shall be increased by 10 %.
...
~:;e~
r~ti~~
cs~~ression-loaded
~~c:. :r~ct~on aGo~ted a: :~~ =~!~ ~oin: can
piles a~ least those values of for uplift-loaded piles and the resis:ar.ce be taken into consideration.
Page 58 DIN VDE 0210 The buckling stability of free-standing piles shall be analysed considering th~ buckling l~ngth and the restraining conditions. Piles embedded in soil are not prone to buckling even ir. very soft layers of soil.
9.6.4.6
Upli~t
tests on construction piles as well as on test
piles Depending on the type of pile, on the subsoil, on the method of installation and on the results of pile driving, uplift tests shall be carried out on at least ·5 % of the installed construction piles. For this, the load shall be increased in incremental steps of the test load up to the uplift working load of the pile and, after unloading, a repeat of this loadine up to 1,2 times the uplift working load (see Fig. 5).· At the incremental steps, the loads shall be maintained until the increase of uplift displace~ent has settled, in any case for at least 3 minutes. I
/j
I
/i
I
I; 'y' ... -· ---- --:-o I Extrapolat1on ,
----------
-· .-
I '
;/
cyde
I
I cyde
I I
Where: Q
Tensile test force Working tensile sentence
load ace.
on = 1,os•o n
Working tensile force 9.6.4.6,last sentence
Q
Failing load
g
s <:
( 1' 2)
~b(l,2)
Uplift displacement due to Q = 1,2 Q n Permanent displace~ent after unloading from Q = 1,2 Q to Q = 0 n
Tension-versus-displacement carried out on piles
last
for testing ace. to Clause
Uplift displacement due to Q
~
~
to Clause 9.6.4.1,
curve
for
loading
DIN VDE 0210 Page 59 The proof of a sufficient uplift strength will be validated, if loading with 1,2 times the uplift working load results in a di~placement that permits extrapolation to an uplift failing load of at least 1,5 times the working load and if the residual displacement after unloading remains within limits which are permissible based on experience. uplift The corded.
tests carried out on construction piles shall be re-
If the proof of the uplift failing load is car~ied out by loaddin5 tests on a separate test pile within the area of the tower site testing with 1,5 times the working load of the pile is adequ.Jtc. In r·cspect :>t.:lllation, pi 1 e.
of design, dimensions and characteristic data of inthe test pile shall comply with the construction
Tr!.:.>ts of uplift failing load at test piles shall be carried out according to Ditl 1054111.76, Appendix A. Wi 1 t~ n t c s t i n g p i 1 e s f o r u p 1 i f t t h e d i s t a n c e o f t h e c e n t r e s o f a c -· tion of the compression reaction may be kept small because of the min0r· influence on the result of the uplift. Howe·Jer, it should b~ not less than 3 m and, due to the influence of the addition~! lo3dings exerted by th~ test bridge, the uplift working load 0 :; h .1 l l be inc r· cas c d by 5 % ( see Fig. 5 ) . n
9.1 Other foundations stability of foundation types which arc not treated under Cl3u:..>es 9.5 and 9.6 (for example slotted foundations, ir.~ec:t:i.on g r o :1 t e d a n c h o r ::; , a n c h o r s •,; i t h e n d p l a t e s , r o c k f o u n d a t i o r. ::; , ;J i l c :.; with expanded pile points, grids of piles) shall be demor.s:rat:ed by appropriate methocs of calculation or by loading test~. Th~
9.8 Design and con3truction of foundations 9.8.1 Concrete foundation 9.8.1.1 Rating Th~
rating and th~ evaluation of forces and bending moments and installation o~ foundation blocks shall be carried out according to Dill 1045 if not stipulated other•,;ise in the follo•,;ing clauses. The conc~ete for unreinforced foundations shall comply at least ~ith the strength quality class B 10, and for reinforced foundation blocks with class B 15. ~he
In o: the
ca~e t~e
of foundations made of unreinforced concrete the ratio n height of steps to the width of the projection shall meet
~inimu~
st~~~gt~
3Ur~~. ~ d ~ ~~ .
r~quire~ents
class 3et~een
according to
Table 13
Cep~nding
or.
the
of the concrete and on the effective soil ~resthe schedul~d values ~t ~ay be !~nearly i~ter~o
page 60 DIN VDE 0210 Table 13. Ratio n of step height to width of the projection of the non-reinforced foundations Str12ngth quality class of concrete
Soil pressure in kN/m
2
100
I 200
I 300
I 400
8 10
1' l
1 '6
2,0
2,0
2,0
B 15
1,0
l '3
1' 6
1,8
2,0
!3 25
1,0
1,0
1 '2
1' 4
1' 6
B 35
1,0
1 '0
1,0
1 '2
1' 3
I
500
If the concrete i~ not reinforced, in case of bending combined with axial forces the maximum compression stress shall be determined neglecting the carrying capacity of the area under Lcn~ior The area under tension may at maximum extend to the ccntr~ of gravity of the cross-section. The area under tension, t: o ·..; r! v c r , ma y b e t ak en i n t o a c c o unt , i f t he t e n s i 1 e s t r e ~ s i s le~~ than 1/10 of the compressive stress simultaneously occurinb in the cross-section. In c~1~>e o!' simple bending without an axial force a tensile stress of l/20 of the permissible compression stress at maximum may be nccepted.
For the structural design of reinforced cross-sections DIN 10115 applies to driven in situ concrete piles, DIN 4026 to prefabricated reinforced concrete piles, DIN 4014 Part 1 and Dlrl 4014 Par-t 2 to large bored piles and DIN 4123 to root-type piles. 9.8.1.2 Embedment of steel members into the concrete by means of anchoring elements If the total tensile or compression load of steel members anchored in concrete is transferred to the concrete by anchor cleats, anchor plates, lugs or the like then it shall be proved th~: the compression stresses between the anchoring elements and th(; cvncrete do not exceed the value of 0,7 * BR and the shearing s~ress in the contour surface of the anchoring elements does not exceed the values in Table 14. If these values are exceeded the resista~te against splitting tensile forces shall be proved.
DIN VDE 0210 Page 61 Table 14.
Values for the permissible shearing and compressive stress in case of anchoring of steel members in concrete Permissible shearing stress
Theoretical values of concrete strength
MN/m 2
MN/m 2
I
MN/m
I
4,9
Strenr;th quality cla:::s of cone ret~
Permissible compressive stress
nR
!3 10
1,0
7' 0
B 15
1' 4
10, 5
7' 4
25
1,8
17,5
12,3
B 35
2,2
23,0
16' 1
B
2
9.8.1.3 Embedment of steel structures in concrete by adhesion ~teel members to be anchored (for example leg member reach closely to the foundation sub face and the tensile mpr·essive loadings are transferred between the steel m•; r:1 h •; r s a nd t h c c o n c r e t e o n 1 y by a d h e s i o n , t h e n t h e p e r r.1 i s s i b 1 e v ,, l1.1 •~ ~ o f t h c b o n d s t r e s s c a n b e t a k e n f r o m T a b 1 e 1 5 .
It
the
:;tt:t::;)
T~bl0
:~ t 0 :·
15.
Values for the permissible bond stress between smooth steel members and concrete
r· c :1 g t h qu.:llity concrete
eLl~~>
Perr.1issible bond stress MN/m 2
8 10
0,4
3 15
0' 5
25
0, 6
B 35
0,7
~
Fer ~his, it r.1ust be ensured that the leg member stubs are closel} encased in concrete along their ~otal length. In case of angle sections or channels the analysis shall be based en the perifery of the enclosed area, e.g. for a single angle section ~he leg lengths plus the hypotenuse. To improve the anchoring additional cleats or the like shall be provided at the leg mer.1ber stubs close to the foundation subface, but are not considered i:. ti':·::! anal:,·sis. 7he
s~resses for steel r.1embers in concrete ca:-1 te :able 9. The bendi:Lg stress in welded seams o: lu~s cleats need not be demonstrated.
:a~e~ 3n~
~er~issible frc~
Page 62 DIN VDE 0210
9.8.2 Foundations made of steel or wood Clause
8.7.2 applies to wooden sleepers.
Table 9 and Clauses 8.4.2.4 and 8.4.2.5 apply to the permissible stresses for steel piles. In case of exceptional loading according to Clause 8.2.2 Clause 9.4.1 applies accordingly.
10. EARTHING DIN VDE 0141 applies to earthing of overhead power lines. 11. CLEARANCES WITHIN THE OVERHEAD POWER LINE
11.1 Clearances within the span Live conductors shall have such a distance from other conductors within the same span that clashing or an approach causing flash-· over will be unlik~ly. In case of multi-circuit lines attention shall be paid to the distances to live conductors of 0ther circuits.
11.1.1 Conductors with equal cross-sections,
having like matcri-
als and equal sags The clearance a of the conductor at mid-span at least
in still air must be
however, not less than k in m. vih ere:
sag in m of the conductor at +40 ·c length in m of that part of the insulator set swinging transversely to the line direction coefficient according to Table 17 minimum clearance in m depending on the voltage according to Table 16. Table 16. Minimum data for clearances depending on voltages Highest voltage
u
m
kV
12 24 36 72,5 123 21.;5
420 T
•'
c~rcui~s
on the same J/' r~
Nominal voltage
Minimum clearance
un
SAM
kV
m
10 20 30 60 110 220 380
0,10 0,15 0,25 0,40 0,75 1, 55 2,70
wi~h varying operational voltages s~ructures the more unfavourable value
run in parallel shall be used.
DIN VDE 0210 Page 63 Tatle 17.
g
tp
an;l~
,I
in degrees
O'to 30'
?: 6 5 ' 1
for coefficient k
Coefficient k Angle to vertical axis within the range
of
R<1:1t;e .:3 •..; ~ !1
Value~
0,95
!I 30'toleo·~o 8o'
I o,75
jgo·
I
I I : 1
Examples for conductors Nominal cross-section in
AAC AAAC
ACSR AACSR 35/6, 50/8 70/12
!o,7o
.I I
55,1 65,0 ll
0,85
~0
I
0,70 !0,65 iI
0, 1 to
0,75
0,65
I0,62
'i5,0
<
44/32,50/30 95/15,120/20 125/30,150/25 95/55,105/75 120/70,170/40 1185/30,210/35 210/50,230/30 240/40,265/35 300/50,3051110 340/30,380/50 385/35,435155 4 5 0 I 4 0 , II 9 0 I 6 5 495/35,510/45 560/50,570/40 I
~~
0' 0
0,70
I 0,62 I,0,60
550/70,650/45 680/85, 10115/115
Copper Bronze
35,5o,1o I I 95,120,1501
.I
185,240, 300
25,35
400,500, I 625,800
50,70 95
1
i
I I
1000
120,150 185,240 30 0' lj 00 500
not mentioned here shall be classified ace. to the angle tp which result.:> from the ratio of the wind load ace. to Clause 8.1.2.1 acting on the conductor to the dead-weight force of the conductor.
~onductors
~wing
Supplement to Table 17 Rt:lative position conductor "l" IJ
0
30
t 0
°
. '' :'
/
---~------
of conductor "2" > 30'
to
eo·
to the vertical through >80' to go·
Page 64 DIN VDE 0210 11 . 1 . 2 Con d u c t o r s wi t h v a r y i n g c ross - s e c t i o n s , ma t o r· l a 1 s o r sag s
vi h ~ n deter min in g the c 1 ear an c e s accord i r. g to C 1 a \l :: c 11 . l . 1 the higher facto: k fro::: Table 17 shall be applied In the case of differint; cross-sections o: materials, c.nd th•J f'.!'Cate: sag in cases where they vary. In addition to the distances for conductors in ntlll ai: according to Clause 11.1.1 the clearances between !1\-lllng conductors shall also be investigated. For this, the wind load shall be assumed according to Clause 8.1.2.1. I~ shall be shown that wh i 1 s t d y n am i c wi n d pressures d i f f e ring by :: 0 % a r'IJ a c t in g or. t he i nd i v i d ua l c on duc t o r s , a c 1 e o. r a n c e no t 1es s t tl ~ n S A11 f r om Table 16, shall be obtained with a minimum cf 0,2 m. 11.2 Clearances at the tower 11.2.1 Mutual clearances of live components t•
Mutuai clearance of live components
.;)AM'
but not less than 0,2 m
11..2.2 Clearances between live and earthed componont:J Mutual :: \-1 L!
ng
clcaro.nce
of the components
po s i t i o n
in still air· .\!J vlell as in a but not less ~1 1\t·l ' than 0 , 15 m
11.2.3 Effect of the insulator set evaluating the clearances according to c;tause 11.?, 0,8 t h (: a ~ g l e o f d c f 1 e c t i o n s h a 1 1 b e c o r. ::; i d e r· •J d f o r d e f l e c t i o n of the insulator set, which results fror.: the r.tt. io of the wind load acting on the conductor to the dead load of the conductor. \·.'hen t i mc s
Fer \~
this,
= cf . q
d
independently of the span length the formula L in kN shall be adopted for the wind load.
This requirement does not apply ta angle suspen3lon towers. 0 - L-( 0 \A-• ~ ~ . f 0 f 'j :t tD, ~ -1 r ··~"· ~-"""- \ ' ·::> I ..o \,_ .,
r;, -(
12. CLEARANCES IN RURAL AREAS Th·; clearances a~o·Je l kV up to
specified as follows apply to opr!rating voltages For higher operating volLJ.ges the clearances shall be increased as follows: 123 kV.
0,75 m 1,80 m
Fo~
operating vo~tage of 245 kV by For operatir.g voltage of 420 kV by
12.1 Clearances in open country c:eara~ce
between conductors and
grou~d
surf:1ce
C!~arance ~o steep slopes being inaccesib~e to traffic cr to sporting activities
6 m 3
r:;
DIN
V~E
0210 Page 65
When evaluating the clearances the following shall be considered: Clauses 4.3.1. and 4.3.2 Maximum sag of conductors Clause 8.1.2.1
Wind load (conductors swung at +40.C)
Clause 12
Increase of clearances in case of operating voltages above 123 kV.
12.2 Clearances in terrain with forests or individual trees In addition to the clearances given in Clause 12.1 the following applies. 12.2.1 Clearance between conductors and trees power line
under the overhead
Clearance between conductors and trees
2,5 m
When evaluating the clearances the following shall be considered: Clauses 4.3.1 and 4.3.2
Maximum sag of conductors
Clause 12
Increase of clearance in case of operating voltages above 123 kV
12.2.2 Clearance line
between conductors
and trees laterally
12.2.2.1 Clearance between conductors and trees, climbed to carry out works:
In case of conductors When evaluating ercd:
the
which are 2,5 rn
in still air clearances the
following has to be consid-
Clauses 4.3.1 and 4.3.2
Maximum sag of conductors
Clause 12
Increase of clearances in case of operating voltages above 123 kV
In case of swung conductors When
of the
evaluating
the
SAM' but not less than 0,5 m
clearances
the
following shall be consid-
er~d:
Clause 4.3.1
Maximum sag of conductors
Clause 8.1.2.1
Wind load +40.C)
(conductors swung at
12.2.2.2 Clearance between conductors and trees for which climbi~g to carry ou~ works has not to be considered.
Clearance to the conductors
SA~'
·
but not less than 0,5 ~
Page 66 DIN VDE 0210 When evaluating the clearances the following shall be considered: Clause 4.3.1
Maximu~
Clause 8.1.2.1
Wind load (conductors swung at +40"C)
12.2.3 Increase of clearances through forests
sag of conductors
for overhead power lines runnine
Ir. case of overhead power lines with operating voltages above 123 kV running through forests the clearance according to Clause 12.2.2.2 should be adequately raised if an increased risk to conductor3 ar.d supports due to falling of trees has to be allowed for.
13. CLEARANCES AND SPECIFICATIONS FOR LINE DESIGN IN THE PROXIMITY OF BUILDING INSTALLATIONS AND TRAFFIC ROUTES 13.l.Gcncral T~1c
cle:1rances specified for the different types of cro.::;sing of in Clause 13 are shown in Table 18.
obj~c:s
For
of and approaches to residential property or to buildings, general methods for establishing of the protuclive areas between the conductors in still air and under swing conditions and the nearest part of the structure are given in Fig. 6. ~ro.::;sing
ot~1er·
following conditions.
Th~
specifications
apply
in detail and for limiting
The
extent
:~p.:1n
or· the spans of approach as well as the associated supports.
of
a crossing or an approach comprises the crossing
If en additional overhead power line crosses with one or several conductors over an existing power line at a crossing then the same measures have to be adopted for that line which would have been necessary in case of direct crossing of each individual in:::tallation. Clearances and line design shall be selected accordingly in case of individual objects not mentioned in the following. Th~
clearances stipulated below apply to operating voltages above 1 kV up to 123 kV. For higher operating voltages the clearances shall be increased as follows: For operating voltage of 245 kV by
0,75 m
For operating voltage of 420 kV by
1,80 m
DIN VDE 0210 Page 67 Cross1ng (Clause 13 21 J
Approach (Clause 13 2 2 l
_; \j
/
3 0. ~ '
~
angle between the conductor in still air and the deflected conductor under wind load ace. to Clau~e 8.1.2.1 (swinging of conductors at +40"C)
.J
increase of above 123 kV
Fig.
clearance
in
case
of
m~x.
operating
voltage~
6. Protective ~hen
in
area between the conductor in still air and under ~ind and the nearest of the building of crossing of residential or other buildings
s~inging
ca~e
13.2 Residential properties and other buildings 13.2.1 Cros:Jing 13.2.1.1 Clearance between conductor building
and the closest part of the
Clearance between conductor and roofs with a slope greater 15" flat roofs and roofs with a slope less than 15• The clearances given above apply to roofs i n g to DI tl 4 l 0 2 Part 7 . Cleara~ce bet~een conductors and ~~stance air-i~flated structures, ~~depe~de~~l; r. --earanc~ ~~~t~c:~:~
of the slope
be~~een
3 m 5 m
with a roofing accord-
roofs with other roofing (for thatched roofs, etc.) 12 m
,
conductors and antennas or lightning
:~~~allations
J..J
•••
Page 68 DIN VDE 0210 13.2.1.2 Evaluation of clearance When evaluating the clearances according to Clause 13.2.1.1 the following shall be considered: Clauses 4. 3. 1 and 4. 3. 2 Clause
8.1.2.1
Maximum sag cf conductors Wind
load
(conductors
+40"C) ~lause
14.8
Sag in case of unequal loads of spans
Clause
13.1
Increase of clearances in case of operation voltages above 123 kV
additional
13.2.1.3 Line design For the design considered:
of
the
overhead
line
the following shall be
Clause
14.2
Attachment of conductors to pintype insulators
Clau.se
14. 3
Attachment of conductors to multiple insulators sets
C~ause
14.4
Attachment of earth wires and telecommunication aerial cables
Clause
14.6
Transformer stations installed on poles
Clause
14.7
Release clamps and rotatine crossarms
13.2.2 Approach llorizo:-:tal clearance between the vertical axis at the swung conductor and the nearest part of the building If this clearance is not Clause 13.2.1 shall apply. For the evaluation considered:
of
the
3 m
met, the specification according to clearance
the
following shall be
Clause
4.3.1
Maximum sag of conductors
Clause
8.1.2.1
vii nd load +40"C)
Clause
13. l
Increase of clearance in case of operating voltages above 123 kV
(conductors
swung at
13.2.3 Utility owned installations For buildings ~arming an operational unit with the overhead line, clearances than required in Clauses 13.2.1 and 13.2.2 may b~ p<:r:::itted. ~maller
DIN VDE 0210 Page 69
13.3 Traffic
in~tallations
This clause applies to ~otorways, high~ays, provincial and county roads, local junction roads and frequently used service and access roads, trolley bus lines and ropeway installations (suspended ropeways, towing and chair lift installations are included in this category), railways with and without overhead traction wires and waterways.
13.3.1 Crossing 13.3.1.1 Vertical clearance between ccnductors and parts of the installation. Vertical clearance between conductor
a~d
the road surface or the top of r~il level for railways 7 m top of rail level if conversion to overhead electric traction is planned 12,5 m components of the overhead traction wire system, of a trolley bus line, of a railway, of a ropeway installation as well as to the agreed gauge of a waterway 3 m
13.3.1.2 Horizontal clearance between
~onductor~
and
part~
of the
installation Horizontal clearance bet•,;een conductors and the fixed components of a ropcway installation or the components of an overhead tr2ction wire ~ystem of a railway towers or support~ng and pulling ropes of a ropeway installation 13.3.1.3 Cl0arances to
~ulti-track
3
~
5
~
ins:allations
In ca3e of railway lines with mc~e than t~o tracks and of stations the clearances shall be deter=ined according to Clauses 13.3.1.1 and 13.3.1.2 in conformity with the federal railway administration in charge if conversion to overhead electric traction is planned.
7he line shall be designed according
t~
Clause 13.3.1.5.
13.3.1.4 s~aluation of clearances When evaluating the clearances accord~~g
to Clause 13.3.1 the
following shall be considered: Clacses
~.3.1
Clacse
8.1.2.1
and 4.3.2
Maximu~
Hind
sag of conductors
load
(conductor
swung
a~
+40"C) Cla,...:se
14.8
Sag d~e to unequal load o:" s;:ar.s
additior.a~
Increase of clearance for ting ~o:~age above 123 kV
c~~r
1
-
PaLe 70 DIN VDE 0210 In
ca~e of crossing of overhead traction installation of a railway t.!lc swing of conducto:"s at +40 ·c due to \-lind load shall be .1 ~~ s u r:1 e d s i mu l tan eo us 1 y with the sag a t - 5 • C w i thou t add i t i on a 1 load for the crossed conductor~ of the overhead traction installation. ,111
In case of crossing of supporting and pulling ropes of a ropeway installation that position of the ropes of the ropeway installation shall be assum~d to be most unfavourable which can occur when the maximum tensile stress is increased by 25 %. When evaluating the line an-:1 a ropeway sidered:
horizontal clearances between an overhead installation the following shall be con-
Deflection of conductors due to ~ind load at +40 the fixed components of the ropeway installation.
·c
towards
Deflection of ropes of the ropeway installation throuEh an angle of 45 • towards the earthed component~ of the overhe01d line. t 3 . 3 . 1 • 5 0 v e r· head Ht: •:
1 i n e des i £in
n ,1 ~~ s i e n i n g the OVC!""head line consideration shJll be Clause lll. 2
Attachment of type insulators
Clause 1 IL 3
Attachment of conductors ple insulator sets
Clause 14. 4
Attachment of earth telecommunication aerial
give~
conductor~
t,,
to
to:
pin-
r::t:lti-
and c~bl~~
Clause 14.5
Use of wood poles
Clause 14. 6
Transformer poles
Clause 1 4. 7
Release clamps and rotating arms
Clause l 4. 9
Clearance between conductors case of unequal iceload
Clause 14.10
Clearance between the conductors in case of failing of an insulator string
on
statior.s
cro~s
in
l3.3.2.Approach 13.3.:'.1
Horizontal clearance between conductors and components of the installation
~=rt~
0
n:al
·~
·~
,j
r.
· -
2 :
clearance cor. c! u c tor an d
between
the vertical axis through the de-
::--:-:: h~ i.~r.: gauge or the compo:1ent:.> o: an ove;head:;3c':~on ~ire installation of a railway or o: a :;~ll~y b•J:; line ':~~ ~ 8 ~ponents of a rope~ay installation
1,5 m
5 m
DIrl VDE 0 2 1 0 Page 7 1
the outer edge of the lane of a motorway, of a of a provincial or a county road, or the edge of a waterway high~ay,
1,5
r.:
If the actual distances are less than the clearances specifie~ in 13.3.2.1 the req~irernents of Clause 13.3.1 apply.
Clau~e
13.3.2.2 Evaluation of clearances When evaluating the clearances according to following shall be considered: Clause 4.3.1
Maximum sag of
Cla1Jse 8.1.2.1
Cla~se
13.3.2.1 the
con~uctor~
Wind load (conductcrs swung at +40"C)
Clause 13.1
Increas~ of clearance in case of operating voltages above 123 ~V
For
the approach to a ropeway installation it shall additionally that its supporting and pulling ropes swing under an angla of 45" towards the overhead line. be
a~sumed
13.3.2.3 Horizontal clearance between towers and railway
rou~es
Horizontal clearance between tower and centre line of the track
n•Jarr~st
If conversion to overhead traction service is planned, h c) r i z o n t a 1 c 1 e a r a n c e b e t wc e n t o we r an d t h e e d g e o : s i n g 1 e o r •ht.:ble track line in open sections, of lines with more th~n two tracks and of installations at stations, so far as individual data are not agreed upon,
5 m
15
r.:
13.3.3 Undcrcrossings V~rtical clearance between conductors and the components of a ropeway installation
When evaluating the clearance ~or
.the following shall be considered:
the undercrossing conductors:
·c
Sag at -20
without
iceload
Clause 13.1 :cr the
rope~ay
T~e
15 ~
5 m
~~~e
c,.·:o:.,~
Increase of clea~ance in ca~~ of operating voltages above 123 ~V
installation:
cu~v~
~
o:
of the rope under load with the sag increased by anc, addit!cnally, the height of the c~bins. ~;idges
c:as!;ir:~
p~~~ecticr. measures shall be taken in or~er to ·..;ith th·e conductors o~ inadmissible proximity.
Page 72 DIN VDE 0210 13.4 Overhead line installations This clause includes overhead power lines of all operating voltages, overhead telecommunication lines of the public service as well as of the Utility's own network. 13.4.1 Crossings operating voltages up to 1000 V circuits with operating voltages
Overhead power circuits with shall be arranged below the above 1 kV.
13.4.1.1 Vertical clearance between conductors and parts of the installation Vertical clearance between conductors and live or earthed components
2 m
This clearance shall to be met, if the horizontal distance between the vertical axis at the deflected conductor and the components of the telecommunicaton line is less than 2 m. 13.4.1.2 Evaluation of clearances When evaluating the shall be considered:
clearances according clause 13.4.1.1 there
For the over-crossing overhead line: Clauses 4.3.1 and 4.3.2
Maximum sag of conductors
Clause
14. 8
Sag in case of unequal load of the spans
Clause
13.1
Increase of clearance in case of operating voltages above 123 kV
Clause
8.1.2.1
Wind load (conductors swung at +40"C). This applies also to the undercrossing line.
additional
13.4.1.3 Line design \.Jh en establishing
the overhead line
there shall be
considered:
Clause 14.2
Attachment of conductors to pintype insulators
Clause 14.3
Attachment of conductors to multiple insulator sets
Clause 14.4
Attachment of earth wires and telecommunication aerial cables
Clause 14.5
Use of wood poles
Clause 14.6
Transformer poles
Clause 14.7
Release clamps and rotating crossarms
Clause 1 4. 9
Clearance between the conductors in case of unequal additional load
stations
mounted
on
DIN VDE 0210 Page 7 3 Clause 14.10
13.11.1.4 Horizontal lines
Clearance between the conductors in case of failing of an insulater string cl~arance
between towers and
teleco~munication
Horizontal clearance between tower and components of an overhead telecommunication line
1,5 m
13.11.2 Approach or running in parallel on common structures Cl~arance~
betwe~n
the other th3n 2 m.
shall
When
the conductors of circuits arranged one above be in accordance with Clause 11, but not le~s
establishing the overhead power line the following shall be
con~idered:
Clause 14.6
Transformer poles
Clause 14.7
Release clamps and rotating crossarms
stations
mounted
on
Ovar·hcad tel8communication line~, including bare wires of utility-owned service telecommunication lines shall be arranged below the overhead power circuits and shall be protected at their supports by means of guard wires. Thi~ does not apply to insulated telecommunication arc referred to as conductors.
For
cabl~s,
which
the
clearances between the conductors of the overhead power and the service telecommunication line, Clause 11 only ~pplies if devices are provided at the service telecommunication line which preclude any hazard to the operating staff if voltages exceeding 1 kV occur. ci~cuits
In all other cases Clause 13.4.1 applies to the clearances between the conductors of the overhead power circuits and the telecommunication line or the service telecommunication line as well as :o the overhead line design. '
13. 11.3 Approach or running in parallel on separate structures 13.4.3.1 Towers spotted at equal or approximately equal intervals The clearances between the conductors in the middle of the span shall conply with Clause 11.
13.4.3.2 Towers not spotted at equal intervals Cl~ 2 r3nc~ ~et~~~r. defl~ct~d conductors due to wind at ~~o ·c and structural components of the other av~r~ea~ line
5 AM but not less than 0,5 n
Page
74
D!tl
VDE 0210
13 .4.3-3 Approach
to overhead telecommunication lines and to poles, where the overhead telecommunication line is connected to underground cables
Horizontal clearance between the vertical axis at the deflected conductors and the components of the telecommunication line or the pole where overhead and underground sections are connected If thi~ clearance Clause 13.4.1 apply.
is
2 m
not met, the specifications according to
13.4.3.4 Evaluation of clearances F0 :· t h r~ c v 2. 1 u a t i on o f t h e c 1 e a ran c e a c co r d i n g to C 1 a us e 1 3 . 4 . 3 . 3 the following shall be considered: Maximum sag of conductors. swung at (conductors load Wind +40"C) in case of Increase of clearance operating voltage above 123 kV
Clause 4. 3. 1 Clause 8.1.2.1 Clause 1 3. 1
13.4.4 Approach to underground telecommunication cable lines or telecommunication earthing DIN VD~ 0228 Part 1 to Part 3 and the Technical Recommendations of th~ Arbitration Agency for Interference Questions (Schied:; t c ll c f ur Bee i n f 1 u s s u n g s f r a g en ) a p p 1 y to t he i n t e r f c r en c e of tel~communication installations by electric power installations. As
far
N0.
3
as clearances are concerned the Technical Recommendation of the Arbitration Agency for Interference Questions applies. Foundations of overhead line towers may not be estab1 i~hcc above telecommunication cables or telecommunication e:arthing. In case of overhead lines which adopt wood poles without earthing the clearance must be at least 0,8 m in all directions. Exceptions must be arranged by agreement with the organisation which runs the installation. 13.5 Play grounds, sports and recreational installations 7his
clause includes for instance play grounds, camping grounds, stadiums, golf courses, tennis courts, riding faciliwatersport facilities.
fcotba~l
tie::;,
13.5.1 Cro!lsing 13.5.1.1 Vertical clearance between conductors and sport grounds ~~r~ical
distance between conductors and
g~neral
sport
~h~
highest
~he
agreed
are~s
~ater
hei~ht
level of swimming pools gauge of sailing facilities
8 m
10 n
3 m
DIN VDE 0210 Page 75 When routing the line or when designing the sports ground care shall be taken to ensure that in case of shooting or sports with throwing implements (for exam~le hammer, javelin, discus) an approac~ to the conductors closer than 3 m is avoided. 13.5.1.2 Vertical clearances installed devices
between conductors and permanently
Vertical clearance between conductors and permanently installed play and sport facilities, start and winning post installations, camping installations as well as structures which can be extended, erected or climbed 13.5.1.3 Vertical fences v~rtical
clearance
conductors
5 m
and prot-::-::tive
clearance between conductors and protective
3 m
fences 1 3 . 5 . 1 . 11 Eva 1 u a t i on of c 1 ear an c e s Wh~n ~h.:1ll
evaluating the clearances according to Clause 13.5.1 there be considered: Cl.J.USCS 4.3.1 and 4.3.2
Maximum sag of conductors
Cl.:1use
Wind load +40.C)
8.1.2.1
(conductors
swung
at
C l .:1 u s e 1 I; • 8
Sag in case of unequal additional load of spans
Cl.J.USC 13.1
Increase of clearance in case of operating voltages above 123 kV
13.5.1.5 Line design When designing the overhead power line the following shall be considered: Clause 14.2
Attachment of conductors to pintype insulators
Cl.J.use 14.3
Attachment of conductors to multiple insulator sets Attachment of earth wires and telecommunication aerial cab~es
Clause 14.6
Transformers poles
stations
mounted on
13.5.2 Approach 13.5.2.1 Clearance lation Hor~=cntal ~~
0f
between
conductor
and
pa~ts
clearance between the ~ertical axis the nearest component
:e~l~c:ec conductors and the ~ports installation
of the
in~tal-
Table 18. Clearances of overhead power lines with voltages above 1 kV in the proximity of buildinc installation~, traffic facilitie~, transmission lines, playgrounds, sports grounds and recreational areas
--o
.,.,
c:l ('0
Inst
Cros ~; i nr,
Conditions for f1ppr·oach <:md runr1 inr, in evaluation\ line par-allel of clearde- \ anr:e:.> 1 si~n
lation crossed by the line
I
Residential proper· ties and other buildings
Clearance between conductor and IJ. 3 .l and 11.3. 2 nearest part of building for roofing ace. to DI!J 1Jl02 Part 7 8.1.2.1 with slope > 15 • 3 m lll. 8
::: 15 • other roofing for antennas and light-
~ng Traffic installations
protective devices
5
m 12 m
13.1
Conditions for evaluation line of cleardeances \ sir;n
Vertical clearance between conductor and road surface or rail level 7 m top of rail if electric traction is planned 12,5 m the components of an overhead traction system, a ropeway installation, the height gauge of a waterway 3 m
l I
14.3 14.4 111.6
i
<
I
11.3 .l Clearance between the vertical axis thr~ur;h the deflected con- 8.1.2.1 ductor 2nd the nearest part of 13.1 the building 3 m
~--------·---------------+
0 ["11
0 N 1-J
0
I--~
11.3 .l Clearance between the vertical axis through the deflected 8.1.2.1 14.4 conductor and 13.1 111.5 the height gauge of a track or 14.6 of components of an overhead 14.7 traction system 1,5 m 5 m 14.9 components of a ropeway 111.10 the edge of a motorway, classified roads or waterway 1,5 m 111.2
14.3
8.1.2.1 111.8
13.1
!Iori zontal clearance between conductor and components of overhead traction system, permanent components of a ropeway 3 m towers as well as supporting and pulling ropes of a ropeway 5 m Undercrossine of traffic installations Vertical clearance between conductor and height gauge of ropeway 5 m I l 3. 3. 3
H
14.7
1
4.3.1 and II. 3. 2
"'0
I
lll. 2
·
3 m1
--l
Horizontal clearance between tower and the centre line of nearest track norr:Jal1y 5 m in case of electric traction planned 15 m
I
-
Cc;~,lir.ued
fr'urn TzJ!.:.Jc l &.
I II!.; L;:dI ill j Oil c r·u:.;:.;cd by L/1C } i liE: Uvt: d1t:<.rd
1 in t: in:.; tal-
l a lions
Cr·ossi ng
Vertical cle<.tranc~ between conductor' and live or earthed components 2 rn (This applies also if the horizontal clearance between the vertical axis ltn·ouch the deflected conductor and the component or a telecommunication line is less than 2 rn) Horizontal clearance between tower and components of an overhead telecommunication line 1,5 m
----1---
Playg r'ounds , :.;po r'l s g r'CJunds
<.t nrJ I' CC I'C<.tlional
cH'(!<.tS
llori zontal clear<.tnce between conductor and sports grounds in general 8 m highest water lcv.of pools 10 m agreed height caugc of ~ailing facilities 3m fixed installed play and sports devices, start ancl winning post installations, camping installations, structures 1-1hich can be extended or erected 5 m protective fences 3 m
1
Conditions for evaluation line of cleardertnces si~n 11.3.1 C~nd 1L3.2 111. 8 13.1 for the under-
crossed l inc:
18.1.2.1
I ,
Hppr'oact, and running in pzH·alle l
I I
Cor~mon
:.;tructures: 14.3 Cleara:' •e between conductor of 111.4 circuiLs arranged one above the 14.5 other ace. to Clausell, but 14.6 not less than 2m ll. 3. l 1 lll. 7 Separate structures: 111.9 Clearance ace. to Clause ll in 8.1.2.1 lll.lOI cz.:sc of to11ers spotted Ztl 3ppr·oximately equal interv::Jls Clearances between the conductors and the components of another line if the towers are not spotted at equal intervals: SAH ace. to Table 16, but not less than 0,5 m Clearance between the vertical I 13.1 axis through the deflected conductor and components of telec omrnu n i cation l in e or of tm:e r \lith underground connection 2 m 111.2
--
lll. 2 l !J. 3 lll. lj
3.2
b.l.2.l Ill,
2
13.1
l 11. 6
Clearance between the vertical axis through the deflected conductor and the nearest cornponei,'.. of a sports installation 3 rn
1
lll. 6 14.7
!-----1
j
11.3.1 and li,
Conditions for evaluation\ line of cleardeances sign
lj.
3. l
8.1.2.1 13.1
t::l H
z
< t::l tr1
0 1\)
...... 0 "'0 QJ
i
I
(lQ (';)
-.l -.l
Page 78 DIN VDE 0210 rr this clearance ~iause 13.5.1 apply.
is
13.5.2.2 Evaluation of
not
met the specifications according to
clea~ances
Wh~~
evaluating the clea~ances according to Clause 13.5.2.1 the fo!!owinG ~hell be considered: Clause
~.3.1
Clause 8.1.2.1
Maximum sag of conductors Wind load
(conductors
swung
at
+40"C)
Increase of clearance in case of operating voltages above 123 kV
Clause 13.1 1~.
SPECIAL SPECIFICATIONS FOR CROSSINGS AND APPROACHES
1 11 . 1 Gc n c r· a 1
Clause 13 stipulates which of the following special specificaticns shall be met in the relevant individual case. 111. 2 At tachrnen t of conductors to pi n-typc insula tor!3 straight line sections the conductor shall be additionally !'a:.;:encd by an auxiliary rope to a second insulator of the same typ~ which is arranged transversely to the line direction.
Wit~in
In cas~ of wood poles in a straight line section, equipped with in:;ulator pins which are not earthed, the attachment with an auxiliary rope to just one insulator is also permitted. T!l·-: ttl·:: tal~
fore~
auxiliary rope shall always consist of the same material as conductor, shall have the same cross-section and shall susthe cor.ductor with at least its maximum working tensile on both sides of the insulator.
1 11.3 Attachment of conductors to multiple insulator sets S~spension
or termination of conductors shall be carried out by insulator sets in which the number of the insulator str~ngs shall be at least the same as generally in the overhead po~er line. :he multiple insulator sets shall be rated according to Clause 6.1.2.4.
mul:iple
1'1.4 Attachment of earth wires and telecommunication aerial cables EJ.!"~~ wire and List~ned twice.
telecommunication
aerial
cables
need
not be
14.5 U3e of wood poles
~oa~
:~all not be used for crossings of motorways, of of railways for public traffic with or without overh~~= :~a~:io~ systems and of ropeway installations. pole=
wa:~~~ay~,
DIN VDE 0210 Page 79 for all other crossings wood poles may only be used in a straight line or ~ith line angles greater than 160", however, for line angles less than 180" A-poles according to DIN 48 351 Part 1 and or:J 4e352 Part 2 shall be used. In case of line angles bet·..1een 180' and 170' a specific analysis is not required. 1~.6
Tran~former
stations mounted on poles
crossing switches and transformers shall only be inWithin a stalled or. supports if they are designed as anchor poles.
14.7
Relea~e
clamps and rotating crossarms
Release clamps and rotating crossarms shall not be used at ing to•,rers.
c~oss
14.8 Sag in case of unequal additional load of spans for the evaluation of the sag it shall be assumed, that the conductors in the crossing span are loaded by the half of the normal or increased additional load at -5 ·c while the conductors in all other spans of the line section are unloaded. 111.9 Clearance
in between conductors additional load
in case of unequal
for the eval~ation of the clearances in between the conductors it sh3ll be assumed that one of these conduct6rs is loaded in the cros~ing span by half of the normal or increased additional load ~t -5 ·c while the other conductors are unloaded.
In
this case a clearance of S ~ according to Table 16 but not th3n 0,2 m shall exis~ 1 between the conductors of the overhead line. 111 . 1 0 C 1 c a r a n c e
between the conductors insulator string
in case of failure of an
•In case of failure of a string of a multiple insulator set the clearance between the conductors in the crossing span shall be at least SAM according ~o Table 16, but at less than 0,2 m. In this ~ose the sags at -20 C shall be taken into account. APPENDIX A GALVANIZING OF TOWERS AND OTHER COMPONENTS ?or gal~anizing
of structures and components made of steel, steel wires and fittings for overhead lines reference is made to the following standards. A.l Structures nut::;
::::I:: 50 9 7 6
and components made of steel
including bolts and
?rotection ~gainst Corrosion; Coatings o~ Iron and Steel Components ~~plied by ~ot Dip Zinc Coating; ?.equire~ent~ and Test~ng
Page 80 DIN VDE 0210 D rr:
5o 9 7 8
Dill 267, Part lG
Testing of Metalic Coatings; Adhesion of Hot Dip Galvanized Zinc Coatings Fasteners; Technical Conditions of Parts
Deli~ery,
Hot Dip
Galvani~ed
Additionally the following applies: The
zinc coating shall be continuous. Zinc beards and residuals ash as well as zinc accumulations in the area of the joints shall be removed without damaging the zinc layer.
of
The oth~r
thickness of layers may be tested according to DIN 50 981 or equivalent methods.
Suitable remedies should be taken against the formation of white r· ll :; t t h e t y p e an d ex t e n t o f wh i c h ma y be a g r e e d u p o n be t wee n t h e involved parties. If the corrosion protection of components made of steel is exceptionally carried out by thermal spraying of zinc the following .1pplics:
Protection against Corrosion of Steel Structures by Thermal Spraying of Zinc and Aluminium; General Principles !'art~; treated in such a way shall be provided after galvanizing with ~n additional coating ·which intensifies the protection .;ffect.
A.2 Steel wires A.2.1 Steel wires for conductors DIN 48 203 Part 3
Steel Wires and Steel Stranded Conductors; Technical Delivery Conditions
DIN 4B 203 Part ll
Wires and Stranded Conductors for Lines; Aluminium Conductors Steel Reinforced; Technical Terms of Delivery
DIN 48 203 Pa~t 12
Wires and Stranded Conductors for Lines; E-AlMgSi-Stranded Conductors, Steel Reinforced; Technical Terms of Delivery
A.2.2 Steel wires for anchor ropes Dlt!
l5!.;B
Zinc Coating on Round Steel Wires
A.3 Caps for overhead line insulators and fittings for overhead linez Fittings for Overhead Lines Hot Galvanization
a~d
Switchgear;
DIU VDE 0210 Page 81 Quoted standards and other documents 12 4
D Itl
Round Head Rivets, Nominal Diameters 10 to 35 mm.
P3rt 1
fasteners; Technical Delivery Conditions; General Req~irements.
DIt I 2 6 7
Fasten~rs;
D I: I 2 6 7
?art 10
Technical Conditions of Delivery; Hot Dip Galvanized Parts. Concrete ar.d Reinforced Concrete; Construction.
10 52
D HI
Timber
Str~ctures,
Design and
Design and Construction.
Part 1 (dr::lft) DIN 1054
Subsoil; Permissible Loading of Subsoil.
DIN 1055 Part l
Design Loads for Buildings; Stored Materials, Building Materials and Structural Members, Dead Load and Angle of Friction.
DtN
Design Loads for Buildings; Soil Characteristics; Specific W~ight, Angle of Friction, Cohesion, ~ngle of Wall Friction.
r .• r
1055 2
t.
DIN 1055 Part 3
Design LoaGs
DIN 1055 Part 11
Design Loads for Buildings; Live Loads on Structures not Susceptible to Vibrations.
DIN 1055
Design Loads for Buildings; Live Loads; and Ice Load.
P .:1 r
5
t
DIN 1548
for Buildings; Live Loads.
Sno~
Zinc Coating on Round Steel Wires. Cast Steels for General Engineering Purposes; Technical Delivery Conditions.
Din
1692
Malleable Cast Iron; Concepts,
Properties.
D Ul 16):; 1
Cast Iron ~ith Modular Graphite; Lo·...; Alloy Srades.
DIN 1705
Copper-Tin and Copper-Tin-Zinc Casting Alloys (Cast Tin Bronze and Gunmetal); Castings.
? .:-. r ':.
DI:I
1714
Ccpper-Alu~inium
(Cast )T'! -
• I
J:~:
?~~-=-
~ -
~?:; '
._
..,1
: ~2': ~
~lu~inium
Unalloyed and
Casting Alloys Bronze); Castings.
Alu~~niu~
Alloys; Wrought Alloys.
~:~~inium
~lloys;
Casting Alloys; Sand Castings, ?ressure Die Cas:ings,
~r3~~:y Di~ Castings, !nves~men~ Casting.
Page 82 DIN VDE 0210 D rr~
3 o51 P<1rt 4
Steel \-lire Ropes, Characteristics; Technical Conditions of Delivery.
Dill 11014 Part 1
Bored Piles of Conventional Type; Manufacture, Design and Permissible Loading.
D I tl
Bored Piles; Large Bored Piles, Manu:acture, Design and Permissible Loading.
II 0 11l
Part 2 DIN 4022 Part 1
Subsoil and Ground Water; Designation and Description of Soil Types and Rocky Soil; List of Soil Courses for Testing and Borin~ without Continuous Gaining of Core Trials.
Ditl
4026
Driven Piles; Manufacture, Dimensioning and Permissible Loading.
Dltl
IJQ91i
Sub~oil;
l
l'clr·t
Dynamic and Static Penetrometers; Dimensions of Apparatus and Method of Operation.
D I rl 11 0 9 11 i' ;1 r t 2
Subsoil; Dynamic and Static Penetrometers, Application and Evaluation.
DIN 11 l 0 2 :· :1 r· t 1
Fire Behavior of Building Materials and Components; Roofing, Definitions, Requirements and TestinG.
i)
!
~;
nr N
lj
l l
3
11 1 111
Part 1 D I r~ l! 1 111 I' ;1 r t 2 DI
ri
11
12 3
DIN 6914
A 1 u m i n i u m i n B u i l d i n g Co n ::; t r u c t i o n , D i r c: c t i o n ~ f o r· Calculation and Design of Aluminium Buildinc Cor:1ponent::;.
Steel Structures; Stability (Buckling, Overturning, Bulging); Method of Calculation, Prescription::;. Steel Structures; Stability (Buckling, Bu l
si
n; ) ;
t·I e t h o d o f
Ca l c u l a t i o n ,
Overturninr,,
D i r e c t i on s .
Protection of Buildings in the Area of Excavations, Foundations and Underpinnings. Hexagon Bolts with Large Widths across Flats for Bolting in Steel Structures.
Hig~-Tensile
D Ul
7 96 8
Hexagon Fitting Bolts; without Nut, Nut, for Steel Structures.
with Hexagon
D!11 7990
Hexagon Bolts with Hexagon Nuts
D PI 8 56 5
Protection against Corrosion of Steel Structures by Thermal Spraying of Zinc and Aluminium; General Principles.
DI 11 17 10 0
Steels for General Structural Purposes; Quality Standard.
::I:l
17200
J: :: l 7 6 6 6
Steels for Quenching and Delivery Conditions.
for Steel Structures.
Te~pering;
Technical
Low Alloy Wrought Copper Alloys; Composition.
DIN VDE 0210 Page 83
18196
DIU
DI~~ l 8 8 0 0
Earthworks; Soil Classification for Civil Engineering Purposes and Methods for Identification of Soil Groups. Steel Structures; Design and Construction.
l
? :J r t
DI~~ 18 8 0 0 ?.Jrt 7
Steel Structures; Fabrication, Suitability for Welding.
DIN 13801
Structural Steel in Building; Design and Construction.
DIN 18808
Steel Structures; Structures Made from Hollow Sections Subjected to Predominantly Static Loacing.
D I t1
Overhead Power Lines; Straight Insulator Spindles.
4 8 0 Ll 4
Verification of
Overhead Power Lines; Bended Insulator Spindles.
DIN 48?.00 Part l DI ;1
ll
32 0 0
Copper
Wire~
for Stranded Conductors.
Bronze Wires for Stranded Conductors.
?art 2 Dt
~~
48200
Wires for Stranded Conductors; Steel Wire3.
?a:-t 3 Din 482oo Part 5 ) I tl
482 00
Wires for Stranded Conductors; Aluminium Wires. E-AlMgSi-Wire~
for Stranded Conductors.
Part 6
DIN 48200 Part 7
Coppe!" Clad Steel Wires
Dill 48200 ?art 8
Aluminium Claded Steel wires for Stranded Conductors.
DI :1 4 S 2 0 l Part l
Copper Stranded Conductors.
D I~~
Bronze Stranded Conductors.
4820 ~
Part 2 D I ~I
48 20 l
?art 3 Ditl 482C2.. 5
?art ::~; ?3.~:
) : ~!
? a:--':
:.s2c:. .:_ ~ .~.: ·~ ;_ ~
for Stranded Conductors.
Steel Stranded Conductors. Aluminium Stranded Conductors. ~-AlMgS:
hl~~ir.:~~
Stranded Conductors. Clad Steel Stranded Conductors.
page 84 DIN VDE 0210
orr:
IJ8203
Part 1
Copper Wires and Copper Stranded Conductors; Technical Delivery Conditions.
Part
48203 2
Wrought Copper Alloy (Bz) Wires and Conductors; Technical Delivery Conditions.
DI :J
4 82 0 3
S t e e 1 \~ i r e s an d S : e e 1 S t r a n d e d Co n d u c t o r· s ; Technical Delivery Conditions.
DI!i
3
Pa:--t
D!tl
48203
5
F-'<1rt
o:r:
L;82G3
r·:::. r
t
(
e o3
Aluminium Wires and Aluminium Stranded Conductors; Technical Delivery Conditions. E-AlMgSi Wires and E-AlMgSi Str~nded Conductors; Technical Delivery Conditions.
ll : r: 11 2 f'art 7
Copper Covered Steel Wires and Copper Covered Steel Stranded Conductors; Technical Delivery Conditions.
Dlt! 118203
Aluminium Clad Steel Wires and Aluminium Clad Steel Stranded Conductors; Technical Delivery Conditions.
P.::.rt 8 [) I ! :
II
e2 0 !J
Steel Reinforced Aluminium Stranded Conductors.
[;
: ;:
I;
8 20 6
Aluminium Alloy Conductors, Steel Reinforced.
!)
~
!:
lj
P, 3 311
Turnbuckles for Overhead Power Lines.
o:n
lj8
3 50
~u~plcmcnt
t~
ur !J
DIN
Telecommunication and Overhead Power Lines Wood Poles. A-Masts,
Formulas and Calculations.
A-Masts,
Main Dimensions.
48351
e
4 3s1
P.::!"t l DI!l 4 8 ~ 5 l
A- 11 a s t s , Bo 1 t e s , Nu t s , Wa s h e r s .
Part 2 DI1!
50049
Materials Test Certificates.
D! :; 50 97 6
Prote~tion against Corrosion; Coatings on Iron and Steel Components Applied by Hot Dip Zinc Coating; Requirements and Testing. •
LI:; 50978
Testing of Metalic Coatings; Galvanized Zinc Coatings.
Adhesion of Hot Dip
DIN VDE 0210 Page 85 D UJ 50981
Measurement of Coating Thickness; Magnetic Met~ods for Measurement of Thickness of Non-ferromagnetic Coatings on Ferromagnetic Material.
DI:J '/GE 0103
M~chanical
D I~~ 1/ DE 0105 ?art l
Operation of Power Installation; General Requirements.
01:1 VDE 0 lll ?:Jr': l
Insulation Co-ordination to Equipment for Three-Phase A.C. Syste~s above 1 kV; Insulation Phase-to-E~rth [veE-Specification].
DI~~
Insulation Co-ordination to Equipment for Three-Phase A.C. System above 1 kV; Phase-to-Phase Insulat:on. [¥DE-Specification]. .
VD2
0 lll P Clr"
t,
2
Dltl VDE 0 lll l !:Jir!
'/DE
fittings
for Overhead Lines and Switchgear; Mechanical Behaviour.
50
DI:J VDS 0212
P.1rt 51 :H :1 1J DE 0212
!'.:>rt 52 1/DE
L'It!
VDE-Specification for Earthing in Installations for Rated Voltages above 1 kV A.C. Stati~ally
0?.~.?
p ;1 r t
and Thermal Short Circuit Strength cf Electrical Power Installations.
)212
fittings for Overhead Lines and Switchgear; Dynamic-Mechanical Behaviour of Antivibration Fittings. Fittings for Overhead Lines and Switchgear; Electrical Contact Behaviour of Current-Carryi~g fittings under Normal Operating Conditions. Fittings for Overhead Lines and Switchgear; Partial Discharge Characteristics, Tests.
?art 53 DI:J VDE 0212
Fittings for Overhead Lines and Switchgear; Hot. Galvanization.
?art 54 D 1 ::
'l DS
? z, r· •.
:._
Provisions in Case of Interference on Telecommunication Installations by Electric Pa~er Installations; Part 1: General [vDE-Specificat:.on] VDE-Specifications for Provisions in the Case of Influence on Telecommunication Installations by Electric Power Installations; Part 2: Influences by Three-Phase Current Systems.
;-, .,. 'I
"""'-·· -: ? :
J--
~
...1
. ; -,-:
~---
VDE-Specifications for Provisions in the Case of Interfere~ce in Telecommunication Installations by Electric ?ower Installations; ?art 3: Interference by Alternating C~rrent Traction Systems.
page 86 DIN VDE 0210 Tests on Insulators of Organic Material for Syste~s with Nominal Voltages greater than 1 kV. Test~ on Outdoor Composite Insulators wi~h Fibr8 Glass Core. [VDE-Guide].
DUJ V DE 4l
Q I;
?art 2 D!:l
'.'DS
? a:-- t
l
c lj !l (j
~
r r:
o:::
'J
Telecommunicatior. Aerial Cables Overheac Power Lines above 1 kV.
Selfsupportin~
8
:) p, l ~,
Insulato;s for Overhead Lines, Contact Wires a~c Telecommunication Lines; Test on Insulators of Ceramic Material or Glass for Overhead Lines with Nominal Voltages greater than 1 kV [VDE-Specification]. on
. ,... .......
.. ' ,., ..J ! -
i;.:;r)uct icn
Recommendations for the Selectio~ of Quality Class8s of Steel for Welded Steel Structures.
009
Guidelines for Protective Measures on Telecommunication Installations of German Federal Post Office with Regard to Interference with High Voltage Systems and Al-Traction Systems Caused by Inductive and Conductive Coupling.
';cchnica.l ?•:corr.m•_! :1d~ ~) 0n :; (i • j
Further documents l
I
I
f: i e B1 i n g , F • Frcileitungen und Umwelt Slektrizitatswirtschaft, Vol. 80 (1981),
p. 681 to 683
- f: i c B l in g, F • , Ne f z g e r , P •
2 I
I
Zur· Wahl der Zugspannung fur die Leiter einer Hochspnnnungs-Freileitung Elektrizitatswirtschaft, Vol. 80 (1981), p. 684 to 691
-
1
3
I
4 I
I
-
I
_,I
Brandt, E., Thomas, R. Der EinfluB der bleibenden Seildehnung auf das Durchhangsverhalten von Freileitungen • Elektrizitatswirtschaft, Vol. 78 (1979), p. 262 to 268 Bauer, E., Brandt, E., Brand, R., Klein, H., Mocks, L., Schlotz, H. Dynamic processes during load transposition in multiple sets with long rod-type insulators CIGRS, 1982, Report 22-03 ::ieBling, F., Ranke, K. Beanspruchung von Freileitungen durch extreme Wind- und ::islasten Elektrizitatswirtschaft, Vol. 79 (1980), p. 683 to 692
T-----.J:.:a.::--:a~le I
~!"or.::
:~~:~c~e~
AusschuB fUr Stahlbau, Ebertplatz 1, 5000 Koln l
? 0 ~~~~~~~technische Zentrale,
Darmstadt
DIN VDE 0210 Page 87 I
- Freitag, ;..., Brandt, E.
6 I
Dyna~ische Beanspruchungen von Mittelspannungsfreileitungen beim Abwurf von Eislasten Elektrizit.atswirtschaft, Vol. 80 (1981), p. 668 to 676
-
1
71
Brandt,::., Griese, W., Gorrissen, I., ~Histenberg, K.-F. Erkenntnisse und Folgerungen der Schleswag aus den Schneenotlagen und ihre Auswirkungen auf den MittelspannungsFreileitungsbau Elektrizitatswirtschaft, Vol. 82 (1983), p. 697 to 705
I
8
Rieger, H., Fischer, R. Der Freileitungsbau Berlin- Heidelberg- New York (1975), 2nd Edition
I
9 I
I
10 I
I
l 1 I
I
-
Schulte, G. Tiefgrundungen im Freileitungs- und Umspannanlagenbau und deren Bemessung Sonderdruck - Lehrstuhl und Prufamt fur Grundbau und Bodenmechanik, Technische Universitat Munchen (1979) Alt, K., Muller, A., Lackner, F. Pfahlgrundungen im Freileitungsbau Elektrizitatswirtschaft, Vol. 77 (1978), p. 669 to 672 Schmidt , B. Pfahlsysteme im Freileitungsbau und ihr Sicherheitsnachwe is T e c h n . Mi t t e i 1 u n g e n AE G- T e 1 e f u n k e n ( 1 9 8 2 ) , p . 1 8 t o 2 11
Previous editions VDE 0210: 07.03; 01.08; 01.14; 07.21; 10.23; 01.30; 02.58; 05.69 Amendments Compared with the edition May 1969 the following has been amended: Contents completely revised; refer to comments.
Page 88 DIN VDE 0210 COMMENTS This standard was revised by the Subcommittee 421.1 "Overhead Power Lines above 1 kV" cf the Committee 421 "Overhead Line.s" of the German Electrotechr.ical Commission within DIN ar.d VDE (DKE) with the aim of adjusting the current standard VDE 0210/05.69 to the newly introduced SI units, to revised DIN standards and to revised standards which are indicated as VDE Specification and to incorporate most recent knowledge concerning for example vibration of conductors, creepage of conductors and loading as.sumptions for supports. ~h~n
revising the standa~d the previous sectioning into topics retained. The denotations of the topics were completed ~ccording to the contents. Where ever possible reference was ~ade to current DIN standards in order to limit the v0lume and to avoid repetition. ~as
Clau~c
2: Definitions
definitions
Thr:: T·~rm:;
Here
of
included
terms were newly arranged and supplemented. for
all overhead line Components and sup-
port:. These were neHly incorporated in Clause 2.2 for towers ~nd in Clause 2.3 for foundations. The functions of the indi·;idu::~
tower types were described.
Lr, Clau:~e 2.4 the term "breaking force'! was replaced by "failing :·or c •_:" and the terms "tens i 1 e stress 11 , "conductor t c mp c rat u r e 11 :1 n d "u n i t we i g h t force r e 1 ate d the c r o 3 s sec t i on" were added . In c l:1 u :; e :-; 2 . 5 11 in:> u 1 at or s 11 and 2 • 6 11 f i t t in g s 11 the terms a 1 ready
3: General requirements
Th~
general requirements were extended by referring to the operational reliability of an overhead power line also in case of electric fault conditions such as short circuits and overvoltages [1]. Clau~e
A~
4: Conductors
the thermal rating of conductors shall be carried out permanent electrical load current as well as for the ~h~rt circ~it loading. The relevant DIN standards and standards lndicated as VDE Specifications form the basis. Investigations carried out with varying conductors demonstrate that unlike DIN ~~E 0103 the maximum temperature of the va~ying conductors must te l!~!ted to the values stated in Table 1 in order to ensure the ~e~~a~ical strength of the conductors. for
ever, the
;:: !"' ~ ·:
i
0
u s 1 'j
to
the
~:~axir.~um
~echanical rating has to be carried out with working tensile stress, long-term stress and
DIN VDS 0210 Page 89 Modifications result from the revision of loading assumptions and recent findings concerning the effect of the everyday stress. The stipulations were newly arranged and summarized in order to provide imprcved lucidity. permissible maximum 4.1.2.1 the Clause According to tensile stress applies at the vertex of the sagging curve
wo~king
at -5 ·c with nor~al additional load and at -20 ·c without additional load and without windload and at +5 ·c '..Jith windload. At the suspension points, values 5 % greater than the maximum working tensile stresses are thereby permissible. In case of increased additional load or of wind acting on conductors with additional load the horizontal component of the conductor tensile stress may exceed the individually permissible maximum working tensile stress. According to str·ess shall conductors at -5 at -5 at -5
·c ·c ·c
4.1.2.2 the permissible long-term tensile Clause exceeded at the support positions of the not be
with three times the normal additional load or with two times the increased additional load or with the normal or increased additional load combined with windload.
Tile first of the mentioned requirements represents an adjustment of the specifications to the current practice. This requirement wa~ in force only for crossings up to now. Therefore, an additional specification for crossings could be o~itted. The second specification complies with the former rule not to exceed the permissible long-term tensile stress in case of higher additional loads than the regular ones in sections without crossings. The third requirement was forced by the establishment of the loading in case of wind action on conductors with additional load. Investigations and operational experience [2] demonstrate that the stres8 of conductors due to aeolian vibration is not determined by the everyday stress to such an extent that just only one limiti~g figure of the everyday stress decides on the hazard due to vibration. In contrast to that, a great nur.Jber of factors i~ involved. Table 1 of VDE 0210/05.69 contained in Columns 4 and 6 limits for the everyday stress, when not exceeding those values no protective measures against vibrations would have been provided. Such a statement is no longer retained in t~e ne~ specifications. The values specified in Table 3 Colur.1n 7, represent directives which if taken into cc~sideraticn will avoid damage due to aeolian vibration by approp~iate measures even in topographically unfavourable areas. The values, there~ore, are independent of the diameter of con~~c:c~s and of the span lengths.
Page 90 DIN VDE 0210 Clause
4.1.2.~
contains details concerr.ing reasons and factors aeolian vibrations. In particular suitable de:ign of suspe~sion and anti~vibration protection devices in cases of increas~d tendency to vibration is now referred to. effec~ing
The
sa~e
values
as for cables of reinforcement.
telecc~~unication ~~ter:al
apply to metal-reinforced conductors their design and the considering
This
requirement was newly incorporated. After detailed disspecifications for metal-free aerial cables (optical fibr~ cables) were not incorporated, since not enough long-term ~xperience was available to specify minimum requirements. Such conductors should be developed under the direct responsibility of the o~ners taking appropriate care of this standard. cussio~,
The specificatons for the design of conductors according to Clause 4.2 and for the minimum cross sections were retained" substantially unchanged and were supplemented by the DIN nomenclature. For AACSR (Aldrey/steel) and for copper wrougth alloys according to DIN 48 201 Part 2 (bronze) the minimum cross sections ~~re raised to 35/6 mm 2 and 25 mm 2 , respectively . .Jubcl2.use 4.3.2 of Clause 4.3 "Sag" was changed. For overhead nowcr lines w~ich are loaded by high currents also during the sum~0r season the actual conductor temperature according to the •! ;.: p '! c t c: d c u r r e n t b u t n o 1 on g e r + 6 0 • C i n a 1 1 c a s e s s h a 1 1 b e t a k e n into account when evaluating the sags. The limiting maximum conductor steady state temperature as specified by relevant DIN ~; t <1 n rj 2 r d s , h o we v e r , s h a 1 1 i n n o c a s e 'b e e x c e e d e d . F.xtonsive investigations carried out during the last years [3] demonstrate that the factual situation alleged in VDE 0210/05.69 whtch said that the permanent elongations of the conductors would not anymore increase after a period of two years after installation ~as not correct. On the contrary, the conductors will elongate during their total service live. Due to the importance of this fact for maintaining the clearances, a special referrence was made in Clause 4.3.4. Clause 5: Conductor accessories The working group "Insulators, Conductors, Fittings" treated in detail the question whether the ratio of the sustaining force of ter~ir.2l cla~ps and tension proof conductor joints to the maximum ten~il~ working force or to the minimum failing load of the conjucto~s should be changed. The result was that the former specification~ satisfied the requirements. Clause 6: Insulators 7h~ c:ause ~as completely revised to adjust the specifications :c the ~~!rent standards for insulators. -~.
~
6.1.1 "Electric rating", in accordance with DIN VDE l ar.d Part 2 reference was made to the responsibility ·.:-.. , ·.-:~::.::;:.:-:stipulating the insulaticr. level.
-;~-
. .1:..se ~~~:
DIN VDE 0210 Page 91 C1 a u s e 6 . 1 . 2 " :·1 e c h a n i c a l r a t i n g " In were kept in force.
t h e a p pr o ve d r a t i ng f a c t o r s
In Clause 6.1.2.4'"1-lultiple ~nsulat.or sets" the specifications in of failure of an insulator string were surnrnari.zed and supplemented to clarify:.ng possible missunderstandings. ca3~
addition, limitati~n of occuring dynamic forces and moment~ required in order to ensure that the failure of an insulator string would not cause the failure of the total insulator set. In
wa~
Inv~stigations carried out on double suspension and double tension insulator set3 demonstrated that in case of failure of an insulator string the dynamic stresses in the remaining insulator string must be deliberately analysed [4]. These deliberations apply equivalently to accessories for insulator sets and other conductor attachments.
Clause
7:
Acce:Jsories attachment!l
for
insulator
sets and other conductor
This clause was adjusted to new standards, for example DIN VDE 0212 P1.1 t 50, Part 53 and Part 54 and rearra;1ged. ln Table 4 additional materials for accessories of insulator sets and other conductor attachments were integrated, and the corresponding rating factors were given. When installing turnbuckles attention shall be paid to ensure that their thread bolts will not be 3tressed by bending. Clause 8: Towers The clause was provided with a new structure together with interheadings which should assist in finding particular topics.
m~diate
Specifications for poles made or solid walls were newly incorporated. Standards for design and manufacture of reinforced concrete poles are under consideration at present. Independently of them this standard applies to the requirements for external loads of overhead lines. The demage which occurred on transmission lines due to extreme iceloads on the conductors some years ago resulted in discussions also in public [5]. The working group "Statical Analysis of Structurez" in•Je::;tigated the damage experienced and the root causes in ord~r to gain indications for revising the specifi~3:ions. The analysis led to the result that the extreme additional loads experienced represented locally limited event::; Which did not necessitate an increase of minimum ~d~itional loads in general.
Page 92 DIN VDE 0210 In order to take effective care of the local ~onditions, supplementarily to the normal additional load an increased additional load was newly established. Increased additional loads shall be assumed as previously in areas where according to experience, increased iceloads have to be expected regularly. In this, attention should be especially directed to the responsibility of the Utility operating the overhead line for attentive stipulation of increased additional loads, where necessary. This responsibility is in force appropriately also for wind loads (see Clause 8.1.2.1). In this case too, higher values than at minimum required by the specifications shall be assumed if according to experience higher wind loads have to be regularly expected. The
loading cases for the tower bodies were clearly gr6uped in Ta~le 7 so that loading cases with the same physical basis were given the same designation for all tower types wh~reby the separ~tion into normal loading cases and exceptional loading cases was maintained .. Loading cases for tower bodies under normal loading were designated by MN, under exceptional loading by MA. Some new aspects resulted for the applications of and assumptions in individual loading cases. For
suspension towers the loading case "Quartering wind action" case MN 4 according to Table 7) applies independently of the tower height. The former limitation on towers with heights of more than 60 m was cancelled since it could not be physically validi.lted. (lo~~ing
o
The former loading case was omitted, since it was dispensible due to the new loading case MA 2. The loadinc; case "Wind on conductors •rith ice" (loading case MtJ 5 a~cording to Table 7) was newly introduced. Wind may act also on conductors with ice. The loading case, therefore, takes care of physical facts. Damage of overhead lines with ice accretion on the conductors showed that the additional wind effects, thereby, played an important role. The exceptional loading case MA 1 qonsiders the torsional loading of towers. For this loading case the assumptions for the reduction of conductor tensile forces in case of suspension and angle suspension towers were newly established (see Clause 8.2.2.2). In case of bundled conductors the reduction amounted formerly always to 25 %. This reduction applies according to the new edition on!y for insulator sets with a length of more than 2,5 m, For shorter lengths of insulator sets a reduction of 35 % shall be cor.sidered. The
reduction of the conductor tensile force of earth wires generally to 65 % instead of the previous 50 %.
anou~ts
DIN VDE 0210 Page 93 Overhead lines with rated voltages up to 30 kV and length: of less than 2,5 m previously also required a reduction of the conductor tensile forces by only 25 %. This di~inished reduction was o~itted. As for all single conductors also a reduction of 50 % shall be considered in these cases in future. This means doubling of the exceptional loading. The above mentioned modifications are validated by the influence of the length of insulator sets on the differences in the tensile forces resulting fro~ varying ice accretion and were dictated also by the conclusions gained from the above mentioned damage due to iceloads. They also take ca~e of additional dynamic loadings in case of iceshedding [6], [7]. crossar~s
Due to local characteristics considerable differences concerning the ice accretion on conductors in adjacent spans and also in adjacent line sections may occur. The newly introduced exceptional loading case MA 2 "unbalanced tensile forces at all conductors of a tower" (see Clause 8.2.2.2) takes care of the effects of unequal ice accretion on all conductors. For suspension and angle suspension towers the differential tensile forces to be assumed in this loading case are stipulated depending on the length of the insulator sets in order to take their· influence into account. This new loading case effects especially the design of towers with circuits installed initially only on one side of a tower. The loading cases to be assumed for the rating of crossarms and earth wire peaks (see Clause 8.3) are systematically grouped in Table 8 analogously to the loading cases for the tower bodies. Loading cases for crossarms and earth wire peaks are nominated as QN for normal loading, and by QA for exceptional loading. Also the specifications for lattice steel towers (see Clause 8.4) amended in some items. The permissible stresses (see T~ble 9) are adjusted to the technical development and to the current DIN standards. In future bolts of the quality 4.6 instead of 3.6 will be used. The shearing and bearing stresses permissible for joints with standard bolts are modified accordingly; additionally, in Table 9 permissible stresses for high strength bolts of shearing/bearing connections are integrated. The Omega-method for the rating of members under compression was retained. The former Table 6 showing the data of relevant cross-sections for the varying loading types was omitted. As far as deviations from practice adopted generally for steel structures are accepted for overhead line towers, these are mentioned in the relevant clauses (see for example Clause 8.4.2.6). Si~ce slenderness ratios greater than 250 are also permitted for compression members of lattice steel towers a formula for the corresponding Omega-factors is given. ~re
.3 p ~ c i :· i c a t i o n s
concerning towers ~ere i~corporated L:ability Insurance. Claus~
t !1 e
"Protection of birds" '-'as integrated to i::: p r::: ·: e of the do~estic population of birds.
e.1o
P~'Jtection
facilities for climbing lattice steel in accordance with the Eoployers'
Page 94 DIN VDE 0210 Clause 9: Foundations DIN 1054, edition November 1976, does not apply to foundations of overhead power lines; the explanations, supplemerit to DI!i 1054, state complementarily that the exclusion of towers of overhead power lines in the scope refers exclusively to structural installations of Utilities. To take care of this fact the stipulations to be observed for the rating and design of foundations of overhead power line towers were presented comprehensively in Clause 9. This meant a complete revison and essential exten~ion of the former specifications. The clause starts with general requ:rements as well as with the classification and denomination of subsoils. Rules for soil investigations and the identification of soils were newly incorporated. The basic principles for design and analysis follo~ which are based on the soil characteristics (shown in Table 12). The treated types of foundations were divided into "Compact foundations" (see Clause 9.5) and "Separate footing foundations" (see Clause 9.6). Compact foundations are characterized in that the tower body is accommodated by a single foundation and additionally to horizontal and vertical forces moments mainly occur as loadings. Separate footing foundations are characterized in that individual foundations for each member stub are provided and each of these foundations must carry mair.ly vertical loads in addition to horizontal loads. The rules to be observed in case of the individual types of foundations were separated into design assumptions and stability conditions. Specifications for the rating of foundations in case of exceptional loading were integrated. The requirements and characteristic data applying to normal loadings can be taken in the latter case whereby the forces resulting from exceptional loading ca~cs have to be reduced by a factor of 0,8 (see Clause 9.4.1). Compact foundations comprise concrete monoblock foundations, concrete slab foundations, raft-type slab foundations and single pile foundations as well as the foundation for wood poles. For rating of monoblock concrete foundations only general assumptions for analysis and stability conditions were specified. Particularities of certain design methods were waived since no method should be especially emphasized. Reference [8] reviews approaches often in use. Conditions for the rating of slab foundations were newly incorporated in order to take care of the frequent use of this foundation type (see Clause 9.5.2). Formulae were given for the proof of the over-turning stability and the soil p:-essure. The
proof
of stability of raft-type slab foundations can be out according to the conditions of concrete slab ~oundations. hdditionally, the loading of the members buried under earth by overburden was mentioned. carri~d
~it~out
goi~g
~ed~ent
and
~er.::o:.ec
into details the transfer of loads by lateral emthe analysis according to a suitable method is i~ case of single pile foundations (see Clause 9.5. 4 ).
Page 92 DIN VDE 0210 In order to take effective care of the local ~onditions, supplementarily to the normal additional load an increased additional load was newly established. Increased additional loads shall be assumed as previously in areas where according to experience, increased iceloads have to be expected regularly. In this, attention should be especially directed to the responsibility of the Utility operating the overhead line for attentive stipulation of increased additional loads, where necessary. This responsibility is in force appropriately also for wind loads (see Clause 8.1.2.1). In this case too, higher values than at minimum required by the specifications shall be assumed if according to experience higher wind loads have to be regularly expected. The
loading cases for the tower bodies were clearly gr6uped in Ta~le 7 so that loading cases with the same physical basis were given the same designation for all tower types wh~reby the separ~tion into normal loading cases and exceptional loading cases was maintained .. Loading cases for tower bodies under normal loading were designated by MN, under exceptional loading by MA. Some new aspects resulted for the applications of and assumptions in individual loading cases. For
suspension towers the loading case "Quartering wind action" case MN 4 according to Table 7) applies independently of the tower height. The former limitation on towers with heights of more than 60 m was cancelled since it could not be physically validi.lted. (lo~~ing
o
The former loading case was omitted, since it was dispensible due to the new loading case MA 2. The loadinc; case "Wind on conductors •rith ice" (loading case MtJ 5 a~cording to Table 7) was newly introduced. Wind may act also on conductors with ice. The loading case, therefore, takes care of physical facts. Damage of overhead lines with ice accretion on the conductors showed that the additional wind effects, thereby, played an important role. The exceptional loading case MA 1 qonsiders the torsional loading of towers. For this loading case the assumptions for the reduction of conductor tensile forces in case of suspension and angle suspension towers were newly established (see Clause 8.2.2.2). In case of bundled conductors the reduction amounted formerly always to 25 %. This reduction applies according to the new edition on!y for insulator sets with a length of more than 2,5 m, For shorter lengths of insulator sets a reduction of 35 % shall be cor.sidered. The
reduction of the conductor tensile force of earth wires generally to 65 % instead of the previous 50 %.
anou~ts
DIN VDE 0210 Page 93 Overhead lines with rated voltages up to 30 kV and length: of less than 2,5 m previously also required a reduction of the conductor tensile forces by only 25 %. This di~inished reduction was o~itted. As for all single conductors also a reduction of 50 % shall be considered in these cases in future. This means doubling of the exceptional loading. The above mentioned modifications are validated by the influence of the length of insulator sets on the differences in the tensile forces resulting fro~ varying ice accretion and were dictated also by the conclusions gained from the above mentioned damage due to iceloads. They also take ca~e of additional dynamic loadings in case of iceshedding [6], [7]. crossar~s
Due to local characteristics considerable differences concerning the ice accretion on conductors in adjacent spans and also in adjacent line sections may occur. The newly introduced exceptional loading case MA 2 "unbalanced tensile forces at all conductors of a tower" (see Clause 8.2.2.2) takes care of the effects of unequal ice accretion on all conductors. For suspension and angle suspension towers the differential tensile forces to be assumed in this loading case are stipulated depending on the length of the insulator sets in order to take their· influence into account. This new loading case effects especially the design of towers with circuits installed initially only on one side of a tower. The loading cases to be assumed for the rating of crossarms and earth wire peaks (see Clause 8.3) are systematically grouped in Table 8 analogously to the loading cases for the tower bodies. Loading cases for crossarms and earth wire peaks are nominated as QN for normal loading, and by QA for exceptional loading. Also the specifications for lattice steel towers (see Clause 8.4) amended in some items. The permissible stresses (see T~ble 9) are adjusted to the technical development and to the current DIN standards. In future bolts of the quality 4.6 instead of 3.6 will be used. The shearing and bearing stresses permissible for joints with standard bolts are modified accordingly; additionally, in Table 9 permissible stresses for high strength bolts of shearing/bearing connections are integrated. The Omega-method for the rating of members under compression was retained. The former Table 6 showing the data of relevant cross-sections for the varying loading types was omitted. As far as deviations from practice adopted generally for steel structures are accepted for overhead line towers, these are mentioned in the relevant clauses (see for example Clause 8.4.2.6). Si~ce slenderness ratios greater than 250 are also permitted for compression members of lattice steel towers a formula for the corresponding Omega-factors is given. ~re
.3 p ~ c i :· i c a t i o n s
concerning towers ~ere i~corporated L:ability Insurance. Claus~
t !1 e
"Protection of birds" '-'as integrated to i::: p r::: ·: e of the do~estic population of birds.
e.1o
P~'Jtection
facilities for climbing lattice steel in accordance with the Eoployers'
Page 94 DIN VDE 0210 Clause 9: Foundations DIN 1054, edition November 1976, does not apply to foundations of overhead power lines; the explanations, supplemerit to DI!i 1054, state complementarily that the exclusion of towers of overhead power lines in the scope refers exclusively to structural installations of Utilities. To take care of this fact the stipulations to be observed for the rating and design of foundations of overhead power line towers were presented comprehensively in Clause 9. This meant a complete revison and essential exten~ion of the former specifications. The clause starts with general requ:rements as well as with the classification and denomination of subsoils. Rules for soil investigations and the identification of soils were newly incorporated. The basic principles for design and analysis follo~ which are based on the soil characteristics (shown in Table 12). The treated types of foundations were divided into "Compact foundations" (see Clause 9.5) and "Separate footing foundations" (see Clause 9.6). Compact foundations are characterized in that the tower body is accommodated by a single foundation and additionally to horizontal and vertical forces moments mainly occur as loadings. Separate footing foundations are characterized in that individual foundations for each member stub are provided and each of these foundations must carry mair.ly vertical loads in addition to horizontal loads. The rules to be observed in case of the individual types of foundations were separated into design assumptions and stability conditions. Specifications for the rating of foundations in case of exceptional loading were integrated. The requirements and characteristic data applying to normal loadings can be taken in the latter case whereby the forces resulting from exceptional loading ca~cs have to be reduced by a factor of 0,8 (see Clause 9.4.1). Compact foundations comprise concrete monoblock foundations, concrete slab foundations, raft-type slab foundations and single pile foundations as well as the foundation for wood poles. For rating of monoblock concrete foundations only general assumptions for analysis and stability conditions were specified. Particularities of certain design methods were waived since no method should be especially emphasized. Reference [8] reviews approaches often in use. Conditions for the rating of slab foundations were newly incorporated in order to take care of the frequent use of this foundation type (see Clause 9.5.2). Formulae were given for the proof of the over-turning stability and the soil p:-essure. The
proof
of stability of raft-type slab foundations can be out according to the conditions of concrete slab ~oundations. hdditionally, the loading of the members buried under earth by overburden was mentioned. carri~d
~it~out
goi~g
~ed~ent
and
~er.::o:.ec
into details the transfer of loads by lateral emthe analysis according to a suitable method is i~ case of single pile foundations (see Clause 9.5. 4 ).
DIN VDE 0210 Page 95 Separate footing foundations (see Clause 9.6) include concrete stepped foundations, augered and excavated foundations, separate grillage foundations and pile foundations. For all types of separate footing foundations it was specified that in case of angle, angle suspension and section towers for ~oading cases MN 1 and MN 2 and in case of terminal towers for loading cases MN 1 and MN 3 (loading of towers by the maximum working tensile forces or by wind, respectively) the rating of the foundations shall be carried out for stabili'ty margins which are increased by 10 % compared to other loading cases. This specification replaces the former requirement to increase the stabilities by 30 % in case of uplift loading of foundations of towers with considerable permanent loads. The reduction of the additional stability margin for such to·wers is valida;;ed by the fact that the working loadings resulting from the loading cases MN 1, MN 2 and MN 3, respectively, are considerably higher than the permanently acting forces. The proof of stability against an uplift loading of concrete stepped foundations (see Clause 9.6.1) can be carried out using the earth frustum method as applicable up to now. However, a generally applicable relation for the determination of the angle of earth frustum was newly established.
\vhere: angle of earth frustum
I?>
B
0
angle of earth frustum for b t
= 1
b
·..; i d th of foundation at
t
effective depth of the surcharging earth volume.
the foundation base
The value B0 depends on the type of soil, the type of installation of the foundation (foundation type U, lowermost step undercut, foundation type A, lowermost step concreted to the undisturbed soil, foundation typeS lowermost step concreted to the shuttering) and the dimensions of the foundation. Table 12 contains relevant data for B . This analytical relation replaced the diagrams previously useg for the determination of the angle of earth frustum. The values e were gained from experience, from tests and from former re?erences aiming at a systematic graduation. Assumptions for design, conditions for the stability and of augered and excavated foundations (see Clauses 9.6.2.1 to 9.6.2.4) were newly integrated since this type of foundation lainec increasing importance and could no longer be treated as a special foundation. The proof of stability against uplift loading i3 carried out, thereby, by the same approach as for stepped :'o•.J:-:C:ations. The values B are adjusted to this type a: :· ') ·~ :--• .::i:::. t :. on . r o r the de term 01 nat ion of the v a 1 u e s B0 ,..-eta 1. -1 e d ~uicance ~as given.
d~sign
Page 96 DitJ VDE 0210 In case of separate g~illage foundations loaded by uplift a theoretical stability against being uprooted of 1,8 instead of 1,5 for other foundations is stipulated as previously (see Clause 9.6.3.3). The Clause 9.6.4 "Pile foundations" was e~sentially extended. Thereby, a series of basic principles was adopted from DIN 1054 in adjusted forrn.The strength of a constructio~ pile can be more reliably determined by a~ uplift test carried out at that pile itself than by analysis or by testing of a separate test pile. In case of proof by analysis values of the surface friction derived from tests will result at best in a proper rating of pile. The difference between the procedu~e of testing const~uction piles [9], [10], [ll] whic!": has proved its worth time and again for overhead lines and tests of ultimate strength carried out on special test piles as generally used in civil enginc~ring was therefore especially emphasized (see Clause
9. 6. 4 •6) . methods of proving the Differing conditions apply to both strength. Uplift tests carried out on construction piles at best ensure the reliability necessary for overhead lines. Such tests shall b~ car~ied out at least at 5 % of the installed con5truction p11es. Thereby, a loading up to 1,2 tim~s the workinc t <: n s i l (; l cad suf f i c es i f t he d i s p 1 a c e me n t s r· ~ c o g n i s e d t h e r e b y stay ~~thin permissible li~it~ and permi~ tne 8Xtrapclation to a ultim~te tensile lo&d which corresponds 2t least to 1,5 times the workin~ tensile load. The distance between the centres of g~avity of the compression r(;action of the used te3ting set-up shall not fall below 3 m. lt 1 s iufluence on the results of the test was taken care of by an increase of the working tensile loads by 5 %. The Cla'Jse 9.8 11 Design and construction of foundations" had to be drafted anew, in respect of non-reinforced and reinforced concrete in accordance with the modifications in DIN 1045. The new classification of concrete strength was observed. Values for the ratio of the height of the step to the width of the projection depending on the quality of concrete and on the soil pressure are stipulated in Table 13 for non-reinforced concrete foundations. :or the anchoring of structural steel stresses are given in Tables 14 and 15. Clause 10: Earthing Reference is made to DIN VDE 0141.
members
permissible
DIN VDE 0210 Page 97 11: Minimum clearances within the transmission line
Clau~e
In Table 16 just one value SA~ (voltage dependent minimum value) measured i:: r:1 is assigned to t:he standardised maximum operating or rated voltages, respectively, which is necessary for the stipulation of the clearances in Clauses 11 to 14. The value S~~ complies with the figure UN/150 used in VDE 0210/5.69. The v~Iues for the maximum operating voltages 245 kV and 420 kV wer~ adjusted to Ditl VDE 0111 Part 3 (Tables 16 and 17) and clearances were increased from 1,5 to 1,55 m and from 2,55 to 2,70 m, r~spectively. rearranged. Table coeffcient 17 "Values for k" Has confir;uration of the table is based en the swing angle of conductors a3 the factor. deciding The
~h
.!. ~·
e
th~
Corresponding values for the coefficient k are assigned to the specified ranges of swin~ angles and examples of conductor types in use Here given. Conductors not mentioned here shall be grouped according to their sHing angle which results from the ratio of the wind load acting upon the conductor ~ccording to Clause 8.1.2.1 and it's dead load. Thereby, the wind load shall be calculated using the formula for spans up to 200 m and taking the wind pressure from Table 5 according to the values for the 0 to 40 m range of heights. The values for k assigned to the individual ranges of swing angle t~ke care of the relative position of the individual conductors. schematic figures associated with Table 17 describe the position of the conductors by means of ranges of angles and their assigned coefficient k. The
r~lative
In case of varying cross-sections, materials or sags of c~n d•.Jctors it shall be proved that no inadmissible approach of conductor.::; will occur (see Clause 11.1.2) if dynamic ·...rind pressures differ by 40 % from conductor to conductor. Clau~e
This
12: Clearances in rural areas
section was compiled withodt significant modifications. clearances applicable previously were retained.
The
minimu~
Clause 13: Minimum clearances and overhead line design in the proximity of building installations and traffic routes
In t.:~r·e
order to avoid repetition of similar clearances the objects surr.r.Jarized to fot.:r groups as follo·...rs:
Residential properties and other buildings Traffic installations o~erhea~ line installations ?lay gra~nds, sports and recreational installations. ·, · - tr.e . . d ·..1:.~. ... h as ·n 0 ·....~ discr-iptir-.., ...• r. .- a::_-:: -~ clearances ·...rere llste - .. , • , .. evaluation of ':.he 1 -l~~1:a~e~u=-1 the c-auses re 1 evant .or ..he ~ . ci~ar~nce~ and for the design of overhead line were mer.tlone~. ~·
98 DIN
?age
V~~
0210
~a~e
In
of crossing of residential or other buildings the varying of roofs were considered if :he roofing co~plies ~ith D.!:i: 11102 Part 7. Since mountable flat roof~ are erected to ar. ir.crea~ing extent raising of clearances fro~ 3 to 5 ~ was required fer :his type of roofs due to safety considerations . ~!ope~
. r:•: protccti•;r~ r:. t o r ::; in st i
areas sho....-r, in Fig. 6 are based or. saGs of conl 1 a i r a c c o r d i n ~;; t o C1 a u s e s 4 . 3 . 1 a n d L: • 3 . 2 a r. d o n ~a~s according to +40 ·c of the swung cor.~~ctcrs justified by the r ;~ r: t , t h a t '.1 i n d n e c e s sa r y f o r s w i n g i n g o f con d u c to r s s i ~ u 1 t a r. r~ ,,usly causes cooling. (: t;
ca.se of crossin;;s of traffic rcute:: 1t sh<:1ll t.·~ ~roves that requirements for clearances bet~ee~ overcrossin[ conductors ! ~~ (" c r 8 s :; e d o b j e c t s i n c a s e o f i n c r e a s e s f s a t; d u e t. o a n u n c: q .: a l additional load of spans according tc Clau~e !L:.8 as w~ll as :· o! · the c l e a r a n c e s be tween t he i n d i ·: i d •..: :: l co n d u c to r· :; i n c a s e o f '·
th~
u n .-.: q u 3 1
add i t i o na1
o f
1oa d
accor d i ng
c on du c t o r s
are
strictly met. Thereby, accou:1t ~ignificance of traffic in~talla:io~s 14.')
d ~ ~~ s i t y of on multiple
t raf f i c
a nd o f
t he
b u n d l i n g-
of
vta~
t o
C 1 a u :; e
taken of the to increasing
due
c l ec t r i c
c i r c ' 1 i L :;
ovcrh0ad power line structure~. The restriction of u:;•! of wood poles accordinc; to Claus>:: l4.5 al:::;o r·cpr·~0·_:nt:; Jn ~~propriate design measure. of overhead power lin~ in~tall~tlo~~ th0 5~mc apply analogou~ly as in c~~e of traffic in~tallaL i o n :; . ;.J h c n c r os s i ng p1a y g r· o u n d s rJ r ;; !1 ~: n a p p r o c-. c h i n c t r-J a d j a r: ~: n t. :; :) or t s f i e 1 d ::; t h c r e was f r e que n t l :: a :; our· c e c f do u b L con ccrnint:. thr:.: interpreting of the specifications. Ther,3forc, this ~ubject was expanded in detail being aware that e~en a ~ore dct~ilcd division would not be able to cover all individu~l case~ ~o:t:ich me::.:; occur for this type of instz,llations. I~
ca~e
of
cro~~ing
~p~cification~
experience the vertical clearances between conductors and used sports grounds could be reduced fro~ 12 to 8 rn.
Fro~
~nnerally
In case of crossing of sports fields or other sports areas it has be ensured that an approach to the conductor of less than 3 m be avoided in case of shooting or sports '.lith throwing i m p l E: r~ e n t. s •
to
wil~
f..ccount was taken of sporting activities on water by incorporo.ting clearances and to the above the maximum water level i! eight gauge agreed upon above lakes and rivers. For ca~ping installations with extendable or erectatle 3n appropriate clearance was specified. Clau~c
~ 1 ll ·~
Particular
14:
~pccifications
componen~s
for crossings and approaches
ad j u .s t. n e n t '::. o t he c u r r e n t l i r. e d e s i g n , s c ::: e c o n d i t i o n s particularly increased additiona~ loads of ~:uc:~r~ ir crossings could be o~~::~d whe~ compared ~~:h t ::,
·~~~~rn~~g
·
·~
;:, r .-:: ·: i c
~~
::;
-:: c! i t ~ o !1
r~~~~re:::e~:s
· :-.
~-
e :-
- •'
p .~ r t. i
~ ·~
t he
of
s t a n da r d .
ccncerning l a:-
s;:;
~
c 1 f
F' ~..: : :
wood poles i c a '::. i on s .
~
e r ::-: 0 r ~
r~sulted
~
:-. e
i~
c o :;1 b i ra a : redu~ing
~
c. :--.
:~e
DIN VDE 0210 Page gg Appendix A:
The -
r~vi~icn
~tr~cture:
Galvanizing of towers and other components ai~ed
at dividing the appendix into:
and cowponents
~ade
of
st~el
as well
a~
colts and
nuts, Steel
wi•~s,
- Cap: for overhead ~nd
at
r~ferring
as
li~e
far
insulators and fittings a~
necessary tc relevant DIN Standard:.
International patent classification H 01 B li 01 8 !! 02 G E 04 H E 04 H E 04 H E 04 H ....t' 04 H E 011 H E 02 D
l/C2 17/00 7/00 12/00 12/08 12/10 12/12 12/20 12/22 27!00
