Office of Director Dam I.D.R., Jaipur
66591175.xls
DESIGN OF A CANAL SYPHON
NAME OF PROJECT :
Case study, Design example 9.4/p394
DESIGN INPUT DATA :
(a) (a) Cana Canal l (i) (i)
Full Full supp supply ly disc discha harg rge e of of can canal al
40.00
Cumec
(ii)
Bed width of of ca canal
18.00
m
(iii (iii))
Full Full supp supply ly dept depth h of cana canall
2.10
m
(iv) (iv)
Bed Bed leve levell of canal canal (C. (C.B. B.L. L.)) at D/S D/S
(v)
Side slope lope of cana canall (s) (s)
(vi) vi)
Free Free boar board d of of can canal al
250.00 m 1.50 :1 0.75
m
(b) (b) Drai Drain n (i) (i)
Max. Max. obse observ rved ed floo flood d dis disch char arge ge
100.00 cumec
(ii)
Bank le level
254.00 m
(iii)
Bed level
251.80 m
(iv) (iv)
Highe Highest st Flood Flood Leve Levell (H. (H.F. F.L. L.))
253.25 m
(v)
slope
1/600
HYDRAULIC DESIGN : (1) Section of the drainage channel According to Lacey's formula = 4.83 X Q 1/2 = 4.83 X 10 = 48.3 Provide bed width of the drain at the crossing P
=
44.50 m.
(2) Canal waterway Bed width of canal Normal X-area of the channel (A)
= = =
18.00 m. BD + 44.42 Sq.m.
Velocity in the normal section
= =
Q/A 0.90
sD 2
m/sec
Adopt size of the barrel as Width
=
Program by- Sunil K Goyal
3.00
m,
Wall thickness
Hydraulic 1
=
0.30
m
Checked by - P.P.Pareek
Office of Director Dam I.D.R., Jaipur
Height
=
Program by- Sunil K Goyal
2.50
m,
No. of barrels
Hydraulic 2
66591175.xls
=
2
No.
Checked by - P.P.Pareek
Office of Director Dam I.D.R., Jaipur
Reduce the canal waterway from Velocity through the barrels
=
18.00 m 40 15
66591175.xls
to
6.30
=
2.67
m/sec
<
6.00
m/sec
m
The veloci velocity ty is is within within the recomm recommende ended d range range The size of the the barrel barrel is, therefore therefore okay It should be checked that the flow is subcritical in the barrel, .i.e., Froude number (F) should be less than unity Now F = V/(gd)1/2 Where, V = 2.67 m/sec g = 9.81 m/sec d = 2.50 m Therefore, F = 0.538 Since nce the the val value of F is less ess than han 1
the the flow flow will be subc subcri riti tica call in the barr barrel el
(3) Head loss and bed levels at different sections : Width of canal in the flumed portion Provide 2 in 1splay in contraction and
=
11.70 Length of contraction transition = -------- X 2 11.70 Length of expansion transition = -------- X 2 Assume,Length of the barrels in the flumed portion=
6.3 3
m in 1 splay in expansion transition
2
=
11.7
m
3
=
17.55
m
70.0 m > 68.50 m assumed length is O.K.
In the transitions, the side slopes of the section shall be warped from 1
2
3
1.50 : 1 to vertical. 4
0.3 m Thick Thick wall Canal 18.0
6.3
18.0
R.C.C. barrels 11.70 1
70.00
17.55
2
3
Canal waterway
Program by- Sunil K Goyal
Hydraulic 3
4 (All dim in meter)
Checked by - P.P.Pareek
Office of Director Dam I.D.R., Jaipur
66591175.xls
At section 4-4 Area of section = 44.42 Sq.m. (Normal channel section) Velocity = Q/A = 0.901 m/sec 2 Veloci Velocity ty head = V /2g = 0.0414 0.0414 m R.L. of bed = 250.00 m (g (given) R.L. of water surface = 250.00 + = 252.10 m R.L. of T.E.L. = 252.10 + = 252.141 m
2.1 0.0414
At section 3-3 Water depth at the entry and exit of the barrel should be kept slightly higher than the depth of the barrels so as to keep the ends of the barrel submerged for proper syphoning Provide water depth equal to 3.00 m Area of section = 3.00 X 6.3 = 18.9 Sq.m. Velocity = Q/A = 2.116 m/ m/sec 2 Velocity head = V /2g = 0.22 0.228 8m Loss of head in expansion from section 3-3 to section 4-4 0.3 (V22 - V12) /2g = = 0.056 m Hence elevation of T.E.L. at section 3-3 = 252.141 + 0.056 = 252.197 m R.L. of water surface = 252.197 0.228 = 251.969 m R.L. of bed = 251.969 3.00 = 248.969 m From section 3 - 3 to section 2 - 2, area and velocity are constant. Head loss through barrels Head loss through barrels is given by ( 1 + f 1 + f 2 xL/R )V 2/2g = Where,
Where,
f 1
=
0.080
f 2
=
a(1+b/R)
a
=
0.00316 , b
L R
= = =
70.0 m A/P 0.682 m
,for bell mouthed syphon
=
0.10000
Hence, f 2
= 0.00362 Ther Theref efor ore e loss loss of head head in barr barrel els s =
Program by- Sunil K Goyal
0.52 0.526 6 m
Hydraulic 4
Checked by - P.P.Pareek
Office of Director Dam I.D.R., Jaipur
66591175.xls
At section 2-2 R.L. of T.E.L.
= = = R.L.o R.L.off water water surfac surface e = = = R.L. of bed = =
T.E.L. at section 3-3 + head loss through barrels 252.197 + 0.526 252.724 m R.L. R.L. of T.E.L. T.E.L. - Veloci Velocity ty head head at sectio section n 3-3 252.724 0.228 252.495 m 252.495 3.00 249.495 m
At section 1-1 Loss of head in contraction transition from section 1-1 to section 2-2 0.2 (V22 - V12) /2g = = R.L. of T.E.L. = = = R.L. of water surface = = R.L. of bed = =
0.037 m T.E.L. at sect ection 2-2 2-2 + hea head loss oss in contract action trans ansition 252.724 + 0.037 252.76 m 252.76 0.041 252.72 m 252.72 2.10 250.62 m
(4) Transitions The general method of Hinds shall be applied for designing the transitions, as the water depths in the transitions vary from 2.10 m to 3.00 m (a) Contraction transition w.s.profile 1 R.L. 252.72
2 y1 = 0.112 x1= 5.85
R.L.
252.50
1 11.70
2 (All dim in m)
Contraction transition y1
= = =
x1
= = =
Program by- Sunil K Goyal
Water level at section 1-1 2 252.72 252.50 2 0.1122
Water level at section 2-2
Length of contraction transition 2 11.70 2 5.85 m
Hydraulic 5
Checked by - P.P.Pareek
Office of Director Dam I.D.R., Jaipur
Program by- Sunil K Goyal
Hydraulic 6
66591175.xls
Checked by - P.P.Pareek
Office of Director Dam I.D.R., Jaipur
C
=
y
=
y1 x12
0.112
=
=
34.223
0.00328 x2
66591175.xls
0.00328
(equation of water surface profile in contraction transition)
The details of the contraction transition have been worked out in Table 1 (b) Expansion transition w.s.profile
4
3
R.L. y1 =
252.10
0.065
R.L. 25 1. 1.97 x 1=
8.78 17.55
4
3
Expansion transition y1
= = =
x1
= = =
Water level at section 4-4 -
Water level at section 3-3 2
252.10
2
251.97
0.0654 m Length of expansion transition 2 17.55 2 8.78 m
Hence, C
=
y
=
y1 2 1
x
0.00085
=
x2
0.07 77
=
0.00085
(equation of water surface profile in expansion transition )
The details of expansion transition have been worked out in Table 1
Program by- Sunil K Goyal
Hydraulic 7
Checked by - P.P.Pareek
Office of Director Dam I.D.R., Jaipur
66591175.xls
Table 1 water Distance
2
y=cx
surface
Elevation Velocity head (hV) of
elevation 1
2
T.E.L.
(4) - (3)
m
m
m
3
4
5
From section 1-1 to 2-2
Velocity V= √2ghV
side
Area A=
slope 's'
Q/V
Bed Level
Depth(D)
Bed
Col.(3)
width
-Col(9) m 6
7
B = A/D -sD
8
9
10 10
11
CONTRACTION TRANSITION
0
0.0000
252.720
252.761
0.041
0.901
1.500 :1
44.392
250.62
2.10
18.00
3.0
0.0295
252.690
252.752
0.062
1.099
1.115 :1
36.406
250.34
2.35
12.86
5.85
0.1122
252.608
252.742
0.135
1.627
0.750 :1
24.593
250.06
2.55
7.73
8.7
0.0295
252.525
252.733
0.208
2.021
0.385 :1
19.794
249.78
2.75
6.30
11.7
0.0000
252.495
252.724
0.228
2.116
0.00 :1
18.900
249.50
3.00
6.30
248.969
From section 3-3 to 4-4
EXPANSION TRANSITION
0
0.0000
251.969
252.197
0.228
2.116
0 :1
18.900
3.00
6.30
3
0.0076
251.977
252.188
0.211
2.035
0.256 :1
19.656
249.145
2.83
6.30
6
0.0306
252.000
252.178
0.179
1.872
0.513 :1
21.372
249.322
2.68
6.61
8.78
0.0654
252.035
252.169
0.135
1.627
0.750 :1
24.593
249.485
2.55
7.73
11.55
0.0306
252.069
252.161
0.091
1.337
0.987 :1
29.913
249.648
2.42
9.96
14.55
0.0076
252.092
252.151
0.059
1.072
1.244 :1 :1
37.300
249.824
2.27
13.62
17.55
0.0000
252.100
252.141
0.041
0.901
1.500 :1
44.392
250.00
2.10
18.00
(5) Invert level Bed level of drain = Provi ovide
0.30
251.80 m
m thick conc oncrete slab and
0.60
m thick earth fill over the slab
Invert level of the concrete
= 251.80 - ( 0.6 + 0.3 + 2.5 ) = 248.40 m Invert level at the entrance and exit of the barrel shall be the same as the bed levels already worked out at sections 2-2 and 3-3 respectively.
Thus the invert level at the entry = The invert level at the exit =
249.495 m 248.969 m
The The inver nvertt level evel of the the barr barrel el woul ould be kept kept at 248. 248.40 40 m in a lengt ength h of 44.5 44.5 m (under base of drain) after which it would meet the respective bed levels at the entrance and exit, so as to obtain a slope of about 1in 15 in the barrel at either side. Thus, Length of barrel upstream = 16.00 m Length of barrel downstream = 8.00 m The length of the pucca floor on either end should be adequate to provide safe hydraulic gradient and its thickness sufficient to counterbalance the total uplift pressure by gravity. The barrel shall be made of reinforced concrete box construction and its structural design is given subsequently.
Program by- Sunil K Goyal
Hydraulic 8
Checked by - P.P.Pareek
Office of Director Dam I.D.R., Jaipur
66591175.xls
(6) Pucca Floor Provide pucca floor in half the transition length in the upstream and 3/4 th the length of expansion transition in the downstream. Length of pucca floor upstream = 1/2 X 11.7 = 5.85 m say 6.00 m Length of pucca floor downstream = 3/4 X 17.55 = 13.16 m = say 13.00 m The floor shall be subjected to static uplift and seepage head; it is maximum when high flood is passing through the drain and there is no flow in the barrel. The seepage head would be calculated by Bligh's theory. (7) Uplift pressures on the barrel floor and pucca floor (a) Static pressure At bottom of barrel floor Deepest est invert level of the barrel = 248 248.40 m The thickness of the barrel is = 0.30 m The bottom level of the barrel floor = 248.10 m Assu Assumi ming ng the the subsub-so soil il wate waterr lev level el upto upto the the bed bed leve levell i.e i.e.a .att R.L R.L.. static head = 250.00 248.10 = 1.90 m
250. 250.00 00 m, the the max maxim imum um
At the downstream end of barrel Floor level at d/s end of barrel = 248.969 m Assuming floor thickness at this point 2.00 m, The bottom level of pucca floor = 248.969 2.00 = 246.969 m Hence, Static head = 250.00 246.969 = 3.031 m At the upstream end of barrel Floor level at u/s end of barrel = 249.495 m Assuming floor thickness at this point 1.50 m, The bottom level of pucca floor = 249.495 1.50 = 247.995 m Hence, Static head = 250.62 247.995 = 2.624 m (b) Seepage head The seepage head will be maximum when the drain is running full and there is no flow in the canal. Thus total seepage head = = H.F.L. in the drain Bed level of cana anal
Program by- Sunil K Goyal
Hydraulic 9
Checked by - P.P.Pareek
Office of Director Dam I.D.R., Jaipur
= =
Program by- Sunil K Goyal
253.25 3.25 m
66591175.xls
250.00
Hydraulic 10
Checked by - P.P.Pareek
Office of Director Dam I.D.R., Jaipur
66591175.xls
At bottom of barrel floor The residual seepage head at point 'a' in the centre of the first barrel has been calculated by Bligh's theory. The seepage line would follow the path indicated by the line x a b y. Its total length (neglecting floor depression or thickness) is the sum of the following (i) (ii) (iii)
Half the barrel span = Length of barrel in indicated portion = Length of pucca floor =
Thus Thus tota totall cree creep p lengt length h= barreel= 1.5 m
1.5 m 8.00 m 13.00 m
22.50 22.50 m and and cree creep p lengt length h upto upto poin pointt 'a' 'a' i.e. i.e. centre centre of fir first st c.c.floor
c.c.cutoff 13.00
8
b
a
y
1.5
x R.C.C.Barrel
Barrel Plan Residual seepage head point 'a' Thus total uplift in the barrel
= =
= say
3.033 m 1.90 + 4.93 m 4.93 t/m2
3.033
At the downstream end of barrel floor total creep length upto the end of barrel floor i.e. at point b = 1.5 = 9.5 Hence , Residual seepage head at this point = 1.88
+ m
8.0
m
Thus total uplift
= Static uplift + residual seepage head = 3.031 + 1.88 = 4.909 m 4.909 The floor thickness required (sp.gr.=2.22) = ----------- = 2.22 Say
2.20
m
Provi ovide
0.90
m at the end of floor
2.20
Program by- Sunil K Goyal
m thick c.c.floor oor d/s and reduce uce it to thicknes ness
Hydraulic 11
2.211 m
Checked by - P.P.Pareek
Office of Director Dam I.D.R., Jaipur
66591175.xls
At the upstream end of barrel floor total creep length upto the end of barrel floor = 1.5 + = 17.5 m Hence , Residual seepage head at this point =
16.00
0.83
m
Thus total uplift
= Static uplift + residual seepage head = 2.624 + 0.83 = 3.454 m 3.454 The floor thickness required (sp.gr.=2.22) = ----------- = 2.22 Say
Provi ovide
1.60
m thick c.c.floor oor u/s and reduce uce it to thicknes ness
1.556
m
1.60
m
0.70
m at the end of floor
**********************
Program by- Sunil K Goyal
Hydraulic 12
Checked by - P.P.Pareek
Office of Director Dam I.D.R.,Jaipur
N I A R D
TRANSITION WING
4.28
TRANSITION WING
4.28
B
0.30 M THICK
R.C.C. BARRELS
A
CANAL
66591175.xls
A
3.00
0 0 . 8 1
0 0 . 8 1
3.00
4.28
16.00
B
44.50
8.00
4.28
CONTRACTION TRANSITION
EXPANSION TRANSITION
11.7
68.50
17.55
PLAN 0.60 TH. EARTH EARTH FILL TOP OF WING WALL
TOP OF WING WALL
R.L. R.L. 253.47 253.47
R.L. 254.00
U/S F.S.L. F.S.L. 252.72 252.72
254.00
H.F.L. 253.25
R.L. 252.85 D/S F. F.S.L.
252.10
CANAL U/ S BED R. L. L.
250. 62 62
249.50
2.50
D/ S R. L. L.
248.97
25 0. 0. 00 00
248.40
U/S TOE WALL
U/S CUT OFF
DRY BRICK PITCHING
5.70
C.C. BLOCK
6.00
16.00
LEAN CONCRETE
C.C. BLOCK
44.50
11.7
TOP OF BANK
254.00 253.25
D/S TOE WALL
4.55
D.B. PITCHING
17.55
SECTION AT A-A
251.80
1 2 3 4 5
TOP OF BARREL ROOF
R.L. 251.20 251.20 3.10
R.L. 248.40 248.40
D/S CUT OFF
13.00
8.00
68.50
H.F.L. OF DRAIN BED LEVEL OF DRAIN
0.30 TH. R.C.C. BARREL
6.90
DETAILS OF PROTECTION WORKS U/S TOE WALL 0.40 X 0.80 U/S CUT OFF 0.50 X 1.00 C.C. BLOCK 0.50 X 0.50 D/S CUT OFF 0.50 X 1.50 D/S TOE WALL 0.40 X 1.00
Drawing 13
Program by - Sunil K Goyal
Checked by- P P Pareek
Office of Directo r Dam I.D.R.,Jaipur
66591175.xls
SECTION AT B-B
6 LEAN CONCRETE 7 D.B.PITCHING
0.15 M THICK 0.40 M THICK
DETAILS OF TRANSITION WINGS
TRANSITION WING
TRANSITION WING
4.28
0 0 . 8 1
4.28
6 8 . 2 1
3 7 . 7
0 3 . 6
0 3 . 6
0 3 . 6
1 6 . 6
3 7 . 7
6 9 . 9
2 6 . 3 1
0 0 . 8 1
6.00 3.00 5.85 4.28
8.70 11.70
CONTRACTION TRANSITION
8.78 11.55 14.55 17.55
EXPANSION TRANSITION
DETAILS OF PUCCA FLOOR
4.28
Office of Directo r Dam I.D.R.,Jaipur
66591175.xls
SECTION AT B-B
6 LEAN CONCRETE 7 D.B.PITCHING
0.15 M THICK 0.40 M THICK
DETAILS OF TRANSITION WINGS
TRANSITION WING
TRANSITION WING
4.28
0 0 . 8 1
4.28
6 8 . 2 1
3 7 . 7
0 3 . 6
0 3 . 6
0 3 . 6
1 6 . 6
3 7 . 7
6 9 . 9
2 6 . 3 1
0 0 . 8 1
6.00 3.00 5.85
8.78 11.55 14.55 17.55
8.70 11.70
4.28
CONTRACTION TRANSITION
4.28
EXPANSION TRANSITION
DETAILS OF PUCCA FLOOR
0.70
5 1 . 1
0 6 . 1
0 2 . 2
2.00 4.00 6.00
0 7 . 1
3.25
0.90
0 3 . 1
3. 3.25
3. 3.25
3. 3.25
13.00
U/S PUCCA FLOOR
Program by - Sunil K Goyal
D/S PUCCA FLOOR
Drawing 14
Office of Director Dam I.D.R.,Jaipur
Checked by- P P Pareek
66591175.xls
Office of Director Dam I.D.R.,Jaipur
66591175.xls
Drawing 15
Program by - Sunil K Goyal
Checked by- P P Pareek
Office of Director Dam I.D.R.,Jaipur
66591175.xls
STRUCURAL DESIGN OF A CANAL SYPHON
NAME OF PROJECT :
Case study, Design example 9.4/p394
DESIGN DATA :
1 UNIT UNIT WEIG WEIGHT HT OF OF DRY DRY EARTH EARTH
1.60
t/m3
2 UNIT WEIGHT WEIGHT OF OF SATURA SATURATED TED EARTH EARTH
2.00
t/m3
3 UNIT WEIGHT WEIGHT OF OF SUBMER SUBMERGED GED EARTH EARTH
1.00
t/m3
4 UNIT UNIT WEIGH WEIGHT T OF CONC CONCRE RETE TE
2.40
t/m3
5 ANGLE OF INTERNAL FRICTION (
φ)
30
Degree
Office of Director Dam I.D.R.,Jaipur
66591175.xls
STRUCURAL DESIGN OF A CANAL SYPHON
NAME OF PROJECT :
Case study, Design example 9.4/p394
DESIGN DATA :
1 UNIT UNIT WEIG WEIGHT HT OF OF DRY DRY EARTH EARTH
1.60
t/m3
2 UNIT WEIGHT WEIGHT OF OF SATURA SATURATED TED EARTH EARTH
2.00
t/m3
3 UNIT WEIGHT WEIGHT OF OF SUBMER SUBMERGED GED EARTH EARTH
1.00
t/m3
4 UNIT UNIT WEIGH WEIGHT T OF CONC CONCRE RETE TE
2.40
t/m3
5 ANGLE OF INTERNAL FRICTION (
φ)
30
6 GRADE OF STEEL 7 GRADE OF CONCRETE 6 DIAMETER OF REINF. BARS
Main Dist
7 NUMBER OF BARRELS
Fe
415
M
20
Degree
16 12
Φ Φ
2
Nos.
8 WIDTH OF EACH BARREL
3.00
m
9 HEIGHT OF EACH BARREL
2.50
m
10 THICKNESS OF BARREL
0.30
m
11 BANK LEVEL
254.00
m
11 DRAIN H.F.L.
253.25
m
12 LEVEL AT TOP OF BARREL
251.20
M
13 UPLIFT AT BASE OF BARREL
Program by- Sunil K Goyal
4.93
Structural 16
Checked by - P P Pareek
t/m2
Office of Director Dam I.D.R.,Jaipur
66591175.xls
(1) Critical section of of the the barrel The barrel shall be subjected to maximum loading under the bank at the lowest possible level of the barrel as indicated below in the following section:Bank level
254.00 m
Saturati on on l in ine
253.25 m R.L. 251.20 m
2.50 R.L.
248.40 m
R.L.
248.10 m
6.90
(2) Design Design feature features s Following cosiderations have been made in the design of barrels : (i) (i) Bott Bottom om slab slab : This This desi design gn is for for upl uplif iftt pre press ssur ure e and and reac reacti tion on from from soil soil resu result ltin ing g fro from m the loading on the foundations. Theoretically, the soil reaction is not uniform but for simplification it is assumed uniform. (ii) (ii) side side walls walls : Side Side wall walls s would would be be tested tested in the the follo followi wing ng two two criti critical cal condit condition ions s (a) High flood in the drain while barrels are empty (b) No water in the drain while barrels are full (iii) (iii) Partit Partition ion walls walls : The part partiti ition on wall walls s are are subjec subjected ted to to equal equal pres pressur sures es on either either side side,, and therefore,no reinforcement is required. Nominal reinforcement is, however, provided to take care of contingency arising due to unequal pressures resulting from chocking up of any of the barrels. (iv) (iv) Top Top slab slab : The The loa loads ds con consi side dere red d for for des desig ign n of top top slab slab are are : (a) Earth load, (b) Weight of water below saturation line As there is no roadway along the drain, no live load due to traffic shall be considered. (3) (3) Desi Design gn As the barrels are rigidly joined, they should be designed as a continuous structure. Hardy Cross method of moment distribution shall be used for design. The effective length of horizontal member = 3.30 m The effective length of vertical member = 2.80 m Distribution factors At joint A For member AB
=
For member AD
=
Program by- Sunil K Goyal
2.8
2.8 +
3.3
2.8
3.3 +
3.3
Structural 17
=
0.46
=
0.54
Checked by - P P Pareek
Office of Director Dam I.D.R.,Jaipur
Program by- Sunil K Goyal
Structural 18
66591175.xls
Checked by - P P Pareek
Office of Director Dam I.D.R.,Jaipur
66591175.xls
At joint D For member DA
=
For member DC
=
2.8
3.3 +
3.3
2.8
2.8 +
3.3
=
0.54
=
0.46
(i) (i) Dead Dead loads loads Consider one meter length of barrel Depth of dry earth over barrel = Depth of saturated earth =
254.00 253.25
Weight of dry and saturard earth = = Weight of top slab
=
0.75 X 5.3
1.60 t/m2
0.30 X
2.40
Weight on the top slab including its own weight = = Weight of the barrels per metre of length =( 4 X 3.3 + 3 = 15.55 t Total dead load/m length of barrels Uplift/m length
=
4.93 X
X
Pressure acting on the base slab
5.3 + 6.02 t/m2
2.8
)
=
52.12 18.08 t
=
2.62
=
0.75 m 2.05 m 2.00
0.72 t/m2 0.72
X
0.30 X
+
-
5.3
2.40
X
6.90
34.04
t/m2
= Soil reaction + = 2.62 + 2 = 7.55 t/m
Net upward pressure on the base slab =
= =
2.05 X
=
15.55 52.12 t 34.04 t
18.08 6.90
253.25 251.20
+
= = 6.90 =
Net vertical load acting on foundation =
Pressure on foundation soil =
-
7.55 2 6.83 t/m
uplift 4.93
0.72
(ii) (ii) Earth Earth pressu pressure re The earth pressure shall comprise of the following : (a) dry eart arth pressure above saturati ation line from R.L. (b) saturated earth pressure from R.L.
Program by- Sunil K Goyal
Structural 19
253. 53.25 253.25
to to
254.0 4.00 248.25
Checked by - P P Pareek
Office of Director Dam I.D.R.,Jaipur
Corresponding to φ = 30 degree , The The pres pressu sure re at A= Surc Surcha harg rge e due due to dry dry eart earth h = Cp X wd X 0.75
Pressure at D
=
1/3
X
=
3.33 t/m2
= = =
3.33 + 3.33 + 7.07 t/m2
1.60 X
Cp
X 1/3 X
66591175.xls
Cp
= 1/3 Surc Surchar harge ge due to satu satura rate ted d eart earth h Cp X ws X 2.20
+ + 0.75
+
ws
X X
1.00
+ w X 2.20 1/3 X 1.0 X + 1 X 2.20
2.20
2.8 + 2.8 +
2.8 2.8
w 1
X X
Loads acting on different members are shown below : 6.02 t/m2 3.33 t/m2
3.33 t/m2
A
B
E
3.30
D
3.30
0 8 . 2
C D
2
7.07 t/m
F 7.07 t/m2
6.83 t/m2
(iii) (iii) Fixing Fixing moments moments (i)
On span AB
=
wl2 12
6.02 =
12
=
(ii)
On span CD
=
wl2 12
5.46 t-m 6.83
3.3 2
X
=
12
= (iii (iii))
3.3 2
X
6.20 t-m
On span span AD AD fix fixed ed end end mom momen ents ts in the the wal walll at at each each end due due to rect rectan angul gular ar porti portion on
=
wl2 12 12
3.33 = =
2.8 2
X 12
2.178 t-m
Fixed end moments due to triangular portion 3.73 X
Program by- Sunil K Goyal
MAD
= =
30 0.98 t-m
MDA
=
3.73 X 20
2.8 2
2.8 2
Structural 20
Checked by - P P Pareek
Office of Director Dam I.D.R.,Jaipur
=
Program by- Sunil K Goyal
66591175.xls
1.46 t-m
Structural 21
Checked by - P P Pareek
Office of Director Dam I.D.R.,Jaipur
66591175.xls
Total fixed end moments at A
= =
2.178 + 3.15 t-m
0.976
Total fixed end moments at D
= =
2.178 + 3.64 t-m
1.46
(iv) Distribut Distribution ion of moments moments Joints Distribution factors Fixed end moments Balance Carry over Balance Carry over Balance Carry over Balance Total
C
D 0.46
-6.20
B
0.54
0.46
6.20
-3.64
3.15
-5.46
-1.18
1.25 -0.69 0.37 -0.17 0.09 -0.05 0.03
1.06
-0.02
-1.39 0.62 -0.34 0.19 -0.10 0.05 -0.02
4.63
-4.63
3.98
-3.98
-0.59 -0.29 -0.14 -0.09 -0.04
-6.98
A 0.54
5.46
0.53 0.32 0.16 0.08 0.04 0.02 6.19
(v) Net moments moments at centre centre and face Span AB 6.02 X 3.3 Sagging moments at face = ------------------2 = Fixing moments at face=
X
-
1.42 t-m 3.98 +
3.15 ( 3.3
=
6.09 t-m
Net fixing moments at face
= =
6.09 4.67 t-m
Sagging moments at centre
=
6.02 X
=
8 8.19 t-m
Fixing moments at centre
= =
Net sagging moments at centre
Program by- Sunil K Goyal
0.15
6.02 X 0.15 2 ----------------------------2
= =
3.98 + 2 5.09 t-m 8.195 3.107 tt-m
6.19 -
3.98
)
1.422
3.3 2
6.19
5.088
Structural 22
Checked by - P P Pareek
Office of Director Dam I.D.R.,Jaipur
Program by- Sunil K Goyal
Structural 23
66591175.xls
Checked by - P P Pareek
Office of Director Dam I.D.R.,Jaipur
66591175.xls
Span CD 6.83 X 3. 3.3 Sagging moments at face = -------------------2 =
X
6.83 X 0.15 2 ---------------------------2
0.15 -
1.61 t-m
Fixing moments at face=
=
3.15 ( 3.3
4.63 4.63 +
6.98 -
4.63
)
6.87 t-m
Net fixing moments at face
= =
6.87 5.25 t-m
Sagging moments at centre
=
6.83 X
1.61
3.3 2 8
= Fixing moments at centre
9.3 t-m
=
6.98 +
4.63 2
=
5.8 t-m
Net sagging moments at centre
= =
9.303 3.498 t-m
-
5.804
Span AD (a) (a)
Due Due to rect rectan angu gula larr port portio ion n = =
(a)
3.33 X
2.8 2
X
0.15
X
0.15
3.33
-
0.15 2
X 2
0.66 t-m
Due to trian riangu gullar por portion tion =
3.73 X 2
2.8
X
= 0.26 t-m Total sagging moments at face
Fixing moments at face
= = = =
Program by- Sunil K Goyal
1 3
3.98 +
-
0.2
0.15 2
0.662 + 0.92 t-m 2.65 2.8
X
X
0.261
(
4.63
-
3.98 )
4.6 t-m
Structural 24
0.05
Checked by - P P Pareek
Office of Director Dam I.D.R.,Jaipur
Program by- Sunil K Goyal
Structural 25
66591175.xls
Checked by - P P Pareek
Office of Director Dam I.D.R.,Jaipur
Net fixing moments at face
= =
66591175.xls
4.6 - 0.92 3.67 t-m
Sagging moments at centre (a)
Due to rectangular portion
=
3.33
2.80 2
X 8
= (b)
Due to triangular portion = =
3.27
t-m
3.73 X 2.80 2 1.87 t-m
X
Total sagging moments at centre
Fixing moments at centre
=
Net sagging moments at centre
= =
4.63 + 2
2.8
X
3.27 + 5.14 t-m
1 7.81
1.87
3.98
=
4.31 t-m
= =
5.14 0.83 t-m
4.31
The net moments at face and centre of the different spans are tabulated below : MOMENTS
Span
At face 4.67 t-m (hogging) 5.25 t-m (hogging) 3.67 t-m (hogging)
AB CD AD
3.11 3.50 0.83
At centre t-m (sagging) t-m (sagging) t-m (sagging)
(vi) Thickness of members The maximum moment in the barrels is Fo r M
σcbc
5.25 tt-m
20 grade concrete and steel of Fe = σst = 70 Kg/cm2
415 1500.00 Kg/cm2
m = 13 k = 0.378 j = 0.874 Q = 11.552 The minimum effective thickness (d) required for bending moment M 5.25 X d = = bQ 100 X = 21.33 cm Adopt overall thickness of all the members = Then effective thickness
Program by- Sunil K Goyal
Structural 26
=
105 11.55
30.0 cm 25.20 cm
Checked by - P P Pareek
Office of Director Dam I.D.R.,Jaipur
(clear cover =
Program by- Sunil K Goyal
Structural 27
66591175.xls
4.0
cm )
Checked by - P P Pareek
Office of Director Dam I.D.R.,Jaipur
66591175.xls
The reinforcement required at various points is given below : (vii)
Reinforcement
Span AB & BE Moments in t-m At face
Reinforcement required At
4.67 t-m (hogging) Prov Proviide
At centre
3.11 t-m (sagging) Prov Proviide
14.13 Cm2 14.0 14.0 cm c/c c/c
= 16 mm bar bars @ At =
9.40 Cm2 21.0 21.0 cm c/c c/c
16 mm bar bars @
Span CD & CF Moments in t-m At face
Reinforcement required At
5.25 t-m (hogging) Prov Proviide
At centre
3.50 t-m (sagging) Prov Proviide
15.90 Cm2 12.0 12.0 cm c/c c/c
= 16 mm bar bars @ At =
10.59 Cm2 18.0 18.0 cm c/c c/c
16 mm bar bars @
Span AD & EF Moments in t-m At face
Reinforcement required At
3.67 t-m (hogging) Prov Proviide
At centre
0.83 t-m (sagging) Prov Proviide
11.12 Cm2 18.0 18.0 cm c/c c/c
= 16 mm bar bars @ At =
2.52 Cm2 25.0 25.0 cm c/c c/c
16 mm bar bars @
Nominal steel shall also be provided on the outer face of the walls for the condition when there is no water in the drain and barrels are running full. The details of reinforcement are shown below 16 mm 16 mm
C.C. C.C. M - 20
φ @
16 mm
φ @ 21.0 cm c/c
16 mm
φ @ 25.0 cm c/c
16 mm
φ @ 18.0 cm c/c
16 mm φ @ 16 mm
0.30
φ @
14.0
cm c/c
14.0 cm c/c 12 mm
φ @
25.0
cm c/c
12 mm
φ @
25.0
cm c/c
12.0 cm cm c/c
clear cover =
4.00
cm
φ @ 18.0 cm c/c
3.00 m
0.30
3.00
0.30
DETAILS OF REINFORCEMENT IN SYPHON BARRELS
Program by- Sunil K Goyal
Structural 28
Checked by - P P Pareek
Office of Director Dam I.D.R.,Jaipur
66591175.xls
*************
Program by- Sunil K Goyal
Structural 29
Checked by - P P Pareek