SANS 282 bending dimensions and scheduling of reinforcement.pdf

Copyright protected. This standard may only be used and printed by subscribers to the SABS Complete Collection of Standards and Related Documents in accordance with a fo rmal copyright agreement. 

ISBN 978-0-626-26322-5 978-0-626-26322-5

SANS 282:2011 282:2011 Edition 6

SOUTH AFRICAN NATIONAL STANDARD

Bending dimensions and sc heduling heduling of st eel reinfor cement cement for fo r concr ete

Published by SABS Standards Division 1 Dr Lategan Road Groenkloof Private Bag X191 X191 Pretoria 0001 0001 Tel: +27 12 428 7911 Fax: +27 12 344 1568 www.sabs.co.za SABS


SANS 282:2011 Edition 6 Table of changes Change No.

Date

Scope

Foreword This South African standard was approved by National Committee SABS SC 59A, Construction standards – Cement, lime and concrete, concrete, in accordance with procedures of the SABS Standards Division, in compliance with annex 3 of the WTO/TBT agreement. This document was published in October 2011. 2011. This document supersedes SANS 282:2004 (edition 5.1). Annex A forms an int egral part of th is document.


SANS 282:2011 Edition 6 Table of changes Change No.

Date

Scope

Foreword This South African standard was approved by National Committee SABS SC 59A, Construction standards – Cement, lime and concrete, concrete, in accordance with procedures of the SABS Standards Division, in compliance with annex 3 of the WTO/TBT agreement. This document was published in October 2011. 2011. This document supersedes SANS 282:2004 (edition 5.1). Annex A forms an int egral part of th is document.


SANS 282:2011 Edition 6

Contents Page Foreword 1 Scope....................... Scope.................................. ......................... ............................ ......................... ......................... ............................ ............................ ......................... .............. ...

3

2

Normative Normative references references ........................ ...................................... .......................... .......................... ........................... ......................... .......................... ................ ..

3

3

Definitions Definitions .......................... ........................................ ............................ ........................ ......................... ............................. ............................ ......................... ............... ....

3

4

Bending dimensions................ dimensions.............................. ......................... ......................... ............................ ............................ ......................... ........................ ............. 4.1 General............................ General.......................................... ......................... ......................... ............................ ......................... ......................... ........................ .......... 4.2 4.2 Scheduling...............................................................................................................

4 4 15

5

Bar and fabric schedules schedules ........................ ...................................... .......................... .......................... ......................... ......................... ......................... ........... 5.1 5.1 General.................................................................................................................... 5.2 Title block ........................ ...................................... ............................ ............................ ......................... ......................... ............................ ..................... ....... 5.3 Bar and fabric marks................... marks................................. ......................... ......................... ............................ ............................ ........................ .......... 5.4 Type and size .......................... ........................................ ............................ ............................ ............................ ......................... ........................ ............. 5.5 Bending schedule schedule ......................... ....................................... ............................ ......................... ......................... ............................ ...................... ........ 5.6 Bending of fabric reinforcement reinforcement ....................... ................................... ........................... ........................... ........................... ................. .. 5.7 Cutting length.................... length.................................. ............................ ......................... ......................... ............................ ............................ .................... ......

21 21 22 22 23 23 23 24

6

Bar or fabric label ......................... ....................................... ............................ ............................ ......................... ......................... ............................ ................... .....

24

7

Manufacturing Manufacturing and routine inspection................... inspection............................. ......................... ............................ ......................... ..................... ............ ...

24

8

Quality evaluation.................. evaluation............................... ........................... .......................... .......................... ........................... ......................... .......................... ................

25

An nex A (normative)

Summary of shape codes ........ ............ ............ .......... ........... ............

26

Bibliography........................................................................................................................... Bibliography........................................................................................................................... 27

1


SANS 282:2011 Edition 6 This page is intenti onally left blank

2

Copyright protected. This standard may only be used and printed by subscribers to the SABS Complete Collection of Standards and Related Documents in accordance with a formal copyright agreement. 


Bending dimension s and scheduling of steel reinforc ement for co ncrete

1 Scope This standard specifies bending dimensions, the methods of measuring bending dimensions and the scheduling of steel bars that are used for the reinforcement of concrete.

2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. Information on currently valid national and international standards can be obtained from the SABS Standards Division. SANS 920, Steel bars for concrete reinforcement. SANS 1024, Welded steel fabric for reinforcement of concrete.

3 Definitions For the purposes of this document, the following definitions apply. 3.1 bend end portion of a bar, bent through 90° with respect to the adjacent portion of the bar and comprising a length n as shown in figures 2 and 3 3.2 bending schedule list in which the nominal sizes, types of steel, cutting lengths, bending shapes and dimensions of bars are given NOTE Throughout this standard, the diameter of a reinforcing bar is indicated as “d” and the standard radius of bending of such bar as "r ".

3.3 calculated length calculated length of a bar, measured along its centre line NOTE Approximate values determined from the formulae given in table 1 are acceptable.

3


SANS 282:2011 Edition 6 3.4 corner change of direction in a bar other than a bend or hook 3.5 cutting length total length (subject to a tolerance of ± 25 mm) specified in the schedule for each bar or for wires in each sheet of fabric, rounded up to the nearest 50 mm 3.6 hook end portion of a bar, bent through 180° with respect to the adjacent portion of the bar and comprising a length h as shown in figures 2 and 3 3.7 run-off leg portion of a bar which is undimensioned and the dimension of which may deviate from the intended dimension, as explained in 4.2.1.4

4 Bending dimensions 4.1 General 4.1.1 Unless otherwise stated in a bending schedule, all dimensions given in the schedule shall be measured as shown in table 1 (i.e. shall be the external (outer) dimensions of the bends as shown in figure 1(b) and figure 1(c)). For deformed reinforcement, the extremities of the deformation shall be taken as forming the outside surface.

4


SANS 282:2011 Edition 6 Table 1 — Measurement of bendi ng di mensions 1

2

3

4 a

Calculated length (measured along centre line)

Information (sketch and dimensions) to be given in bending schedule

20

A

Straight

36

( A + C + E) + 0,57 (B + D) - 3,14d

Shape code

Method of measurement of bending dimensions

If B or D > 400 + 2d, see note 1 of 4.2.5 A + B - ½r - d 37 If r is non-standard, use shape code 51 A + B + C - r - 2d

38

A + B + C - r - 2d A + 0,57 B + C - 1,57d 39

If B > 400 + 2d, see note 1 of 4.2.5. Where so desired, the standard radius r for corners may be increased, but shall not apply to end anchorages denoted by h or n. See 4.2.3.1. NOTE 1 r indicates the minimum values in figures 2 and 3. NOTE 2 The dimensionless sections of the bars are the run-off legs. NOTE 3 Ensure that dimension B is greater than 14d for smooth mild steel and greater than 18d for deformed steel. NOTE 4 The length formula is approximate and when bending angles exceed 45°, the length should be calculated more accurately allowing for the difference between the specified overall dimensions and the true length measured along the centre line of the bar or wire. a

These lengths are approximate and generally involve a slight positive difference from the exact mathematical expressions.

5


SANS 282:2011 Edition 6 Table 1 (continued) 1 Shape code

2 Method of measurement of bending dimensions

3 Calculated length (measured along centre line)

4 a


If angle with horizontal is 45° or less A + B + C otherwise see note 4 41

If angle with horizontal is 45° or less 42

A + B + C + n otherwise see note 4


A + 2B + C + E otherwise see note 4


A + B + C - ½ r - d otherwise see note 4 If angle with horizontal is 45° or less

48

A + B + C otherwise see note 4

Where so desired, the standard radius r for corners may be increased, but shall not apply to end anchorages denoted by h or n. See 4.2.3.1. NOTE 1 r indicates the minimum values in figures 2 and 3. NOTE 2 The dimensionless sections of the bars are the run-off legs. NOTE 3 Ensure that dimension B is greater than 14d for smooth mild steel and greater than 18d for deformed steel. NOTE 4 The length formula is approximate and when bending angles exceed 45°, the length should be calculated more accurately allowing for the difference between the specified overall dimensions and the true length measured along the centre line of the bar or wire. a

6



SANS 282:2011 Edition 6 1 Shape code


3

4


a



A + B + C otherwise see note 4 A + B - 0,43 R - 1,21d

51

If R is standard, use shape code 37 If R > 200 mm See note 1 to 4.2.5 3

A + B + C + D - /2 r - 3d

52

A + B + C + D + E -2r - 4d

53



7





4 a


A + B + C - r - 2d

54

A + B + C + D + E -2r - 4d

55

2 A + 2B + 2n - 3r /2 - 3d

60


8






4 a



A + C otherwise see note 4 A

65

2 A + B + 2h - r - 2d

72

See note 3

2 A + B + C + n - 3r /2 - 3d

73



9


SANS 282:2011 Edition 6 Table 1 (continued) 1

2

Shape code


3 a Calculated length (measured along centre line)

4 Information (sketch and dimensions) to be given in bending schedule

2 A + 3B + 2n - 2r - 4d

74

A + B + C +2D + E + n - 5 r /2 - 5d 75

2 A + r + d + 2h

81

For larger radii, see 4.2.5, note to table 5 and refer to shape code 99

A + 2B + C + D - 2r - 4d

83

Where so desired, the standard radius r for corners may be increased, but shall not apply to end anchorages denoted by h or n. See 4.2.3.1. NOTE 1 r indicates the minimum values in figures 2 and 3. NOTE 2 The dimensionless sections of the bars are the run-off legs. NOTE 3 Ensure that dimension B is greater than 14d for smooth mild steel and greater than 18d for deformed steel. NOTE 4 The length formula is approximate and when bending angles exceed 45°, the length should be calculated more accurately allowing for the difference between the specified overall dimensions and the true length measured along the centre line of the bar or wir e. a

10



SANS 282:2011 Edition 6 Table 1 (concluded) 1 Shape code

2

3

4



a


A + B + 0,57C + D - ½r - 2,57d 85

If C is greater than 400 + 2d, see 4.2.5

C B

(A

d)2

B2

X

Where X = 2 · · (A-d) and B does not exceed A/5 or 150 mm, whichever is the least.

86

There shall be at least two full turns in the helix.

Where an additional turn is required at the helix' end(s), it shall be treated as a shape code 99.

Provide either a dimensioned sketch or a referenced sketch with dimensions A, B, C, D, E/R shown in the schedule 99

All other shape codes

The dimension that is to allow for the permissible deviation shall be indicated, as shown in the relevant cases in column 4 of this table.



11



a) Slope of cr anked bars

b) Dimensio ns of cranked bars

c) External dimensions of bent bars Figure 1 — Cranked and b ent bars

4.1.2 Dimensioning reinforcement that requires special end preparation shall be consistent with the method of dimensioning for the reinforcement schedule. 4.1.3 The individual dimensions of a bar specified in a bending schedule shall be subject to the tolerances given in table 2.

12


SANS 282:2011 Edition 6 Table 2 — Cutting and bendi ng to lerances Dimensions in millimetres 1

2

3

Method of formi ng

Length

Tolerance

Cutting

Bending

Straight lengths (including reinforcement for subsequent bending) 1 000 mm > 1 000 to > 2 000 mm

± 25

±5 2 000 mm

+5 -10 +5 -25

4.1.4 The dimensions for the scheduling of reinforcement bounded by concrete faces shall allow for the appropriate tolerances shown in table 2, plus the tolerances allowed for formwork and concrete cover to reinforcing bars. 4.1.5 To facilitate packing for transportation, each bent bar shall fit inside an imaginary rectangle, of size 18 m × 2,2 m. NOTE 1 Normally the length of a bar should not exceed 13 m, although longer lengths can be obtained by special agreement with the supplier. NOTE 2 Certain bar types are supplied in coils. For helical bars (shape code 86 in table 1), check with the manufacturer as to which steel is available in roll form, i.e. in lengths considerably in excess of 13 m.

4.1.6 The standard values for minimum radii, bend and hook allowances (r, n and h respectively, as given in figures 2 and 3) shall app ly to all shape code s, as applicable. If la rger values are required, then the bar shall be treated as a "non-standard" bar (code 99) in accordance with 4.2.1.2. Where a non-standard radius is specified (for example, shape codes 51 and 65), it shall be not less than r .

13



Dimensions in millimetres 1

2

Nominal size of bar d Hook allowance h Bend allowance n Radius r a

a

6 100 100 12

3

4

5

6

7

8

9

8 100 100 16

10 120 100 20

12 120 100 24

16 160 100 32

20 200 120 40

25 260 160 50

32 320 200 64

Non-preferred.

Figure 2 — Minimum hook , bend and radiu s allowances for hot-roll ed mild st eel bars th at comply wi th SANS 920

14

10 40 400 240 80



Dimensions in millimetres 1 Nominal size of bar d Hook allowance h Bend allowance n Radius r a

2

3 a

6 100 100 18

a

8 100 100 24

4

5

6

7

10 120 100 30

12 160 100 36

16 200 120 48

20 240 140 60

8

9

25 300 180 75

32 400 220 96

10 40 480 260 120

Non-preferred.

Figure 3 — Minimum hoo k, bend and radius allowances for high yield stress steel bars and cold -worked steel bars that comply with SANS 920

4.2 Scheduling 4.2.1 General 4.2.1.1 Each bar or sheet of fabric shall be scheduled completely and without referen ce to earlier schedules. 4.2.1.2 The preferred shape codes are given in table 1 (see also annex A). Shapes that do not have a specific shape code number as given in table 1 shall be coded "99" (see table 1).

15


SANS 282:2011 Edition 6 4.2.1.3 If coded as 99, the sketch shall be fully dimensioned or reference dimensioned in accordance with table 3, its dimensions being shown in the appropriate columns headed A, B, C, D and E/r of the schedule. 4.2.1.4 For all shapes, the dimension of th e run-off leg (see column 4 of table 1), shall be allowed to deviate from its intended length by the sum of all tolerances. 4.2.1.5 No dimension given in table 1 shall be give n a zero value, as this will change the basic shape.

16


d n a s d r a d n a t S f o n o i t c e l l o C e t e . l p t n m e o m C e  r e S g B a A t S h g e i r h t y o p o t c s r l e a b m i r r o c f s b a u h s t i y b w d e c e n t a n d i r r p o d c n c a a n d i e s s t u n e e b m y u l c n o o D y d a e t m a l d r e a R d n a t s s i h T . d e t c e t o r p t h g i r y p o C

s l i a t e d g n i d n e b d r a 3 d 1 n a t s n o n d n a g n i x i F

: v e R t c e j o r P

: . o N e l u d e h c S c

r

r m ) o 2 c m 8 2 E S N A c 1 S m 1 ( D m s a e e d m l o m u c d 0 e 0 e 1 c h 1 p f C m a c m o h s s s r r l a o e f p b i t m l c a 9 s n u B m f o i m o s n e n i l c p 8 e m A m i m m d a , x g E n i e e d — p d n a 7 e 3 h o B S c e

e t a D

2 1

l b a T

n o i t c e S

: f e r g n i w a r D

d e k c e h C n w a r D

0 4

2 3

5 2

b

6

5

g n i c 4 r o f n i e R

h t g n e L

m m

l . a o t o T N r k r a a B m

3

r e e d t p n e y m T a i a d

2

. h o i n c a N e

r e b 1 m e M

, d n f k r a o . a e o z N M i s

0 2 s e s s a M 6 1

0 0 2 2 9 9 S S N N A A S o 0 S t 1 ) o t a ) P a P M M 0 0 5 ( 5 4 8 2 e ( i l l e s e n t e r s t e h l l t d g a i i e S . T . t m M H o M H a T = = i D R Y 2 1

. d r a d n . a m t s m s i h 0 5 t f h t i o w s e s l p i e i l t l p u m m o n c i e t h l u g d n e e h l c g s i n s t t i h u T C

. m m 0 1 f o s e l p i t l u m n i s n o i s n e m i d g n i d n e B

a

c

b

17


SANS 282:2011 Edition 6 4.2.2 Hooks and bends 4.2.2.1 Unless otherwise stated in a bending schedule, the proportions and dimensions of the hooks and bends shown in column 4 of table 1 shall conform to the appropriate values given in figures 2 or 3, as relevant, subject to variations as may follow from tolerances in other portions of the bar. 4.2.2.2 For all shapes with two or more bends in the same or opposite directions (whether in the same plane or not), the overall dimension given in the schedule shall always include a minimum straight length between the curved portion of the bends, as shown in figure 4. The value of this straight portion shall be not less than the following (see SANS 920): a) 4d for material with characteristic strength of 250 MPa; b) 4d for material with characteristic strength of 450 MPa and not exceeding 20 mm diameter; and c) 6d for material with characteristic strength of 450 MPa.

Figure 4 — Example of bar wi th more than one bend 4.2.2.3 The overall off-set dimension of a crank shall be not less than twice the diameter of a circle that circumscribes the bar or the wire. The angled length, as shown in figure 1, shall be not less than the following: a) 10d for material with a characteristic strength of 250 MPa; b) 12d for material with a characteristic strength of 450 MPa and not exceeding 20 mm diameter; and c) 14d for material with a characteristic strength of 450 MPa and exceeding 20 mm diameter. 4.2.2.4 The length of material to be used in the determination of the calculated length to form a bend or hook shall be as given for n or h in figures 2 and 3.

4.2.3 Radii of bends 4.2.3.1 The internal radius of a bend, hook or corner of a bar (where the radius is not specified asr as in table 4 or can be determined from dimensions) should be twice the nominal size of the bar, in the case of hot-rolled mild steel bars, and three times the size of the bar, in the case of high yield stress steel bars and cold-worked steel bars (see figures 2 and 3). Where so desired, the radius for corners may be increased. This change shall be indicated as shape code 99.

18



4.2.3.2 The internal radius of corners marked with a radius r or where the radius can be determined from a dimension, shall be not less than the radius as specified in 4.2.3.1. 4.2.3.3 Corners in non-standard bars shall comply with 4.2.3.1 or 4.2.3.2, as applicable.

19

SANS 282:2011 Edition 6 c

r

r o

8 1

m m

c

E

7 1

d n a s d r a d n a t S f o n o i t c e l l o C e t e . l p t n m e o m C e  r e S g B a A t S h g e i r h t y o p o t c s r l e a b m i r r o c f s b a u h s t i y b w d e c e n t a n d i r r p o d c n c a a n d i e s s t u n e e b m y u l c n o o D y d a e t m a l d r e a R d n a t s s i h T . d e t c e t o r p t h g i r y p o C

) s t e e h s d r a d n a t s n o n ( e l u d e h c s c i r b a f a f o e l p m a x E — 4 e l b a T

s n o c 6 i 1 s n C e m i 5 d c 1 g B n i d n e c 4 b A 1 r o s l s i l i a t a t e e d d l 3 a g 1 i n c i e d p n S e B

m m m m

0 0 3 6

m m

0 5 1

t c e j o r P

e e p d a h o S c

8 3

1 1

t h e t b e i B h d S w

m m

0 1

t h e t b e g h n L e S l

m m

9

8

7

s a t e d t e e h 5 s r o e c n e r 4 e f e R 6 l i

3

20

D

2 1

: v e R

m m

c

a

s 2 4 g O O n a h r e 1 3 v O O O

0 2

0 5 4 2

0 0 6 6 0 0 3

0 5

0 0 3

5 2

h t g n e L

m m

0 0 6 6

0 5 4 2

h c t i P

m m

0 0 1

0 5 2

0 1 Y

8 0 Y

f d o n r e e a t r e e i p m w y a T i d l f s a o e t r o . i T o n w / t s e . e o f e r h N o i w s

0 4 2

0 0 3

0 2

5 2

2

s . t e o f e o N h s

2 1

1

c k i r r b a a F m

2 0

n o i t c e S

: . o N e l u d e h c S

e t a D

: f e R g n i w a r D

d e k c e h C n w a r D

2 1 0 0 2 2 9 9 S ) . s 0 7 7 S N a m . e 1 7 7 A P s m m 9 9 N S M s A 5 m a o 8 S t 2 5 M o ) 5 f f t 4 a o o ( 0 0 ) P s s 8 9 9 a d e l e 2 2 P M o l r p i p M 0 e . i t l t 4 l r 0 5 i u u ( w 2 5 4 0 2 e n 1 m m ( l 6 n n l i w S i i e s n r a N d d e t t e d A i e i e s f r i f i S e h d d c c l i t l i g l a o e e e e S . T . t e p p m M H o M H C S S S a T = = = i D R Y Z a b c


SANS 282:2011 Edition 6 4.2.4 Angles 4.2.4.1 Unless otherwise stated in a bending schedule, the angle formed at a bend shall be a right angle. 4.2.4.2 In the case of an angle of a corner that is not a right angle, a) if the overall height is critical, the angle shall be defined by a slope length and an offset, as shown in figure 1(b), and b) if the slope is critical, the angle shall be defined by the length of the slope and the rise, as shown in figure 1(a).

4.2.5 Curved bars A bar that has to be formed to a radius less than or equal to the appropriate value given in table 5, shall be bent to the required curvature before being placed in its final position. Reinforcement to be formed to a radius exceeding that given in table 5, shall be supplied straight and the required curvature can be obtained during placing. NOTE 1 For shapes with straight and curved lengths (for example, shape codes 39, 51, 81 and 85 in table 1), the largest practical radius for the production of the continuous curve is 200 mm (this value should be checked with the bending yard concerned) and for larger radii the curve may be produced by a series of short straight sections. NOTE 2 A section of up to 300 mm at each end of a bar cannot be radiused. If necessary, the cutting length should make allowance for these lengths to be r emoved from the radiused portion.

Table 5 — Maximum bendi ng radiu s 1

2

Nominal size of bar

Critical radius

mm

m

8 10 12

2,5 3 3,5

16 20 25

5 7 17

32

43

NOTE If a larger radius is required, the bar should be supplied as a straight bar and the required radius can be obtained during placing (see also notes to 4.2.5)

5 Bar and fabric schedules 5.1 General NOTE The purpose of the provisions given in this clause is to obtain uniformity in the compilation of bar and fabric schedules. The implementation of these provisions should lead not only to easier interpretation of working drawings but also to simplification of the preparation of a bending and cutting list.

21


SANS 282:2011 Edition 6 5.1.1 The bar and fabric schedules shall be separate an d shall be drawn up as shown in tables 3 and 4, respectively. Individual schedules shall be done on A4 sheets, but larger sheets of the A series may be used in such a way that the schedules can be cut or folded to a nominal A4 size. For simple structural components such as beams, columns and rectangular column bases (but not only them), the assembly drawing of the component may be included on the same sheet as the schedule. Such drawings may be produced on A3 sheets on which the width of the schedule should be confined to the nominal width of an A4 sheet.

5.1.2 All hooks, bends and corner radii of bars shown in figures 2 and 3 shall be deemed to be standard values and are not reflected in dimensions in the schedule. For non-standard bars, dimensions of standard hooks, bends and corner radii may be omitted and where so omitted they shall be deemed to be standard values. NOTE For computer produced schedules, the column widths and the size of the schedule may vary from those shown in figure 2 and 3, but the sequence of columns should be maintained. The schedule should not be significantly larger than size A4.

5.1.3 The bar or fabric schedules shall include the statement "This schedule complies with SANS 282".

5.2 Tit le bloc k The title block shall appear either at the top or at the bottom of the schedule. The following information shall be displayed in the title block: a) the name of the project; b) the number of the project; c) the component type and the location (which shall appear in the title block or elsewhere in the schedule); d) a cross reference to a layout drawing number; e) the schedule number with an optional revision number. This should appear close to the righthand edge of the schedule. If the revision number does not form part of the schedule number, then the revision number shall be shown separately but adjacent to the schedule number; f) the name of the organization responsible for the design of the project; g) the date the schedule was prepared; h) the signatures or printed initials of the engineer and the checker; and i) such other information as the design organization deems necessary for the adequate control and administration of the project. NOTE Where a revision of the schedule is necessary, the line or lines affected may be indicated by a suitable reference on the schedule.

5.3 Bar and fabric marks The bar mark given in column 3 of table 3 and the fabric mark given in column 1 of table 4 shall consist of the identifying numbers or letters (or both), that shall also be displayed on a label (see clause 6), which shall be attached to the bars or to the fabric. Bar and fabric marks should consist of a range of consecutive numbers/letters, and no mark should consist of more than three characters.

22


SANS 282:2011 Edition 6 The numbers should be taken from the range 01 to 99 and the letters should be taken from the range A to YY. Where such ranges are inadequate, use either a) a combination of letters taken from the range A to YY, followed by a single-digit number, or b) a combination of numbers taken from the range 01 to 99, preceded or followed by a letter. Combinations starting with "E" shall be reserved for bar marks where special end preparation is required (for example, couplers).

5.4 Type and size In the "type and diameter" column, the types of steel and the nominal sizes of bars (given in SANS 920), shall be indicated in abbreviated (symbol) form, as follows: a) symbols R

denotes plain round mild steel bars, of strength 250 MPa;

Y

denotes high yield deformed steel bars, of strength 450 MPa; and

Z

denotes types of steel not covered by R or Y;

b) sizes: The size of the bar is given after the symbol and indicates the nominal diameter of the bar in millimetres. NOTE Where possible, mesh may not be listed on the same schedule as bar reinforcement.

5.5 Bending schedule 5.5.1 The bending dimensions given in table 3 and table 4 should be multiples of 5 mm, and due regard should be given to the applicable requirements and bending tolerances in table 2.

5.5.2 Shapes of shape code 99 shall be shown in sufficient detail (see annex A) to facilitate cutting and bending, or they shall be supported by a dimensioned sketch. The method for the measurement of dimensions in table 4 shall be used. The total length shall be given, and unless there is an end anchorage bend or hook, one bending dimension, preferably an end dimension, shall be indicated as the free dimension, to allow for permissible deviations. The r , n and h values, if different from the values given in figure 2 and figure 3, shall be given in the schedule. The tolerances in table 2 also apply to shape code 99.

5.6 Bending of fabric reinforc ement 5.6.1 The sketch in column 13 of table 4 shall indicate the following: a) the direction of bending relative to the transverse wires (see figure 5(a));

a) Positi on of transverse wires

23


SANS 282:2011 Edition 6 b) the direction of the longitudinal wires of the sheet, to ensure bending about the correct axis (see figure 5(b));

b) Indication of longitudinal wires c) the correct orientation of an asymmetric sheet, to ensure the correct setting out of bending dimensions (see figure 5(c)).

c) Orientation of an asymmetric sheet Figure 5 — Positio ns of fabric reinf orcement

5.6.2 For all bent fabric reinforcement, the bending dimensions shall not be indicated at positions near welded transverse wires that occur within four diameters of the start of a bend (see figure 6).

Figure 6 — Positi on of weld ed transverse wires

5.7 Cutting length The length of a bar shall be the cutting length as defined in 3.5.

6 Bar or fabric label The bar or fabric label shall contain sufficient information to identify the bar or fabric in terms of the relevant schedule.

7 Manufacturin g and routine inspection 7.1 Purpose-made shearing equipment shall be used for cutting bars to length. The tolerances given in table 2 shall apply to each length.

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SANS 282:2011 Edition 6 7.2 Bending shall be carried out on power bending machines. Plain smooth surfaces or rolls that do not offer resistance to longitudinal movement of the bars or fabric being bent shall be provided to ensure adequate support. The diameter of formers that are used in bending bends and hooks in accordance with figure 2 and figure 3 shall be such that bends and hooks will be provided of the radii given in figure 2 and figure 3, subject to the appropriate tolerances.

7.3 The manufacturer shall ensure that cutting and bending machine operators are trained in the skills necessary to produce cut and bent products of dimensions within the permissible size deviations and of consistent quality. A formal operative approval and testing system shall be implemented and operators shall have been certified by the manufacturer as having achieved the minimum standards of competence.

8 Quality evaluation Quality evaluation shall be carried out in accordance with SANS 920 in the case of steel bars and in accordance with SANS 1024 in the case of steel fabric.

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An nex A (normative)

Summary of sh ape codes Table A.1 gives a summary of shape codes. Table A1 — Shape codes

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NOTE 1 Use shape code 99 for all other shapes. A dimensioned sketch of the shape shall be given in the bending schedule. NOTE 2 Radii of all bends are standard unless r is given in the be nding schedule. NOTE 3 All dimensions are external (outside) dimensions.

Bibliography SANS 10144 (SABS 0144), Detailing of steel reinforcement for concrete.

© SABS

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SANS 282 bending dimensions and scheduling of reinforcement.pdf

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