DESIGN DESIGN OF CIRCULAR CIRCULAR WATER TANK ( D o m i c a l
Name of work:- pkn 1 Tank capacity 2 3
Live load Free board
4
Conrete
5 6 7
400000 ltr
M
scbc
Steel fy Nominal Cover Reinforcement Top Dome (main / distri. ) Top Ring Beam Main two ldge srirrups
Vertivcal
(Water side )
Ring bars
t o p an an d b a s e )
Depth of water 2
mm
3 unit weight 25000 N/m m 13 115 N/mm2 Tensile stress Effective Cover mm 35
8
mm F
160
20
mm F
4
8
mm F
300
mm c/c
12
mm F
110
mm c/c
110
mm c/c
2
N/mm
wt of water 200 mm
N/m
mm c/c both way Nos.
Distribution steel
8
mm F
210
mm c/c
8
mm F
90
mm c/c
30
mm F
8
Nos
Bottom Ring Beam
3
N/mm m
12
(both di
m
1400 0.20 20 7 415 25
(both direction)
Bottom Dom slab
4.00 9800
8 mm f 160 160 mm c/c c/c 350
2000 11600
230
20 mm f Ring
4
12 mm f Bars
220
mm c/c
210
mm c/c
110
mm c/c
Nos
4000 8 mm f
12 mm f Bars 12 mm f 110 110 mm c/c c/c
8 mm f Bars 90 mm c/c c/c Both Both side side 8 8
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Nos. Bars mm f strirup
30 200
850
mm f
mm c/c 550
DESIGN OF CIRCULAR WATER TANK (Domical top and base) Tank capacity Live load Free board Conrete
400000 1400 0.20 M20 cbc 7 fy 415 25
Steel Nominal cover
ltr 2 N/mm m
Depth of w ater = 4.00 wt of water = 9800 = 200 wt. of concrete = #### m = 13 Tensile stess = 115 Effective cover = 35
2
N/mm 2 N/mm mm
1 D e s i g n C o n s t a n t s : - For For HYSD HYSD Bars Bars 2 sst = 115 N/mm
scbc = k =
7
N/mm
0.442
wt. of concrete
2
m = J
=
0.853
R
=
= ####
2
N/mm
3
13 1.318
Effective depth of tank
=
2
xD
If D is the inside diameter of tank, we have =
N/mm mm
Cocrete M - = 20
2 Dimention of tank:-
from which D
m 3 N/mm mm 3 N/mm
400
x
4
3.143
x
3.80
=
4
11.57
Provide a diameter of
x
m
11.60
=
3.80
=
say
=
4.00
- 0.20 =
3.80 m
400000
x
1000
1000
x
1000
11.60
m
m
3 D e s ig Membrane analysis: ig n o f r o o f d o m e : - We shall design the top dome and ring beam on membrane analysis, analysis considring these to be independednt of tankwall which is assumed to be freee at top, Let the rise of the dome be = 2.00 m and its thickness = 100 m R = 11.60 / 2 = 5.80 m 3 3 . 6 + 4 the radius r is given by = R2 = (2r - rise) rise = 5.80 2= (2r(2r-2 2)2 = = 9.41 m 4 2500 N/m2 Self load of dome = 0.1 x 1 x 1 x ## #### = 1400 N/m2 Live load = Total load 3900 N/m2 = 5.8 7.41 = = 0.616 and = 0.79 or f '= 38 degree sin f cos f = 9.41 9.41 2 wr 1- cos f wr cos f + cos f -1 Hoop stress = Maridian stress = 2 t 1+cos f t sin f Maximum hoop stress oqurs at f = 0 1+1-1 3900 x 9.41 and its magnitude = = 183495 N/m2 = 0.1835 N/mm2 Safe 0.1 1+1 38 degree Maximum meridian stress will be at F = f = 3900 x 9.41 1- 0.787 and its magnitude = = 206002 N/m2 = 0.206 N/mm2 Safe 0.1 0.379 The stress stress are with in safe limit. However However provide provide minimum minimum reinforceme reinforcement nt @ 0.3 % of area in each direction. direction. 0.3 2 = x 1000 x 100 = 300 \ As mm 100 2 3.14xdia 3.14 x 8 x 8 mm2 using 8 mm mm bars A = = = 50 4 x100 4 x 100 Spacing of hoop Bars = 1000 x 50 / 300 = 167 say = 160 mm Hence Provided 8 mm F bar, @ 160 mm c/c in both direction. 3 Design of ring beam :-
The thicknes kness s of dome
=
120 mm assum sumed
Meridional thrust per metre length of dome at its base.= 206002 x1 x Horizontal component T per metre length .= 24720 cos 38 = 24720 x
\ hoop tension
= 19466
[email protected]
x
11.60 2
=
112903
steel required =
0.12 =
24720 N/m
0.79 =
19466 N/m
112903
/
115 = 982
mm
2
2
3.14xdia 3.14 x 20 x 20 = = 314 mm2 4 x100 4 x 100 No.of hoop Bars = 982 / 314 = 4 No. say 4.0 No. Hence Provided 4 No. 20 mm F Ring bar, for symetry. 2 1256 Actual , Ast = 4 x 314 = mm E uivelent area of com osite section of beam of area of cross section A is =A+(m-1)Ash= A +( 13 1 )x 1256 = A+ 15072 112903 2 = = 1.2 Allowing a stress of 1.2 N/mm in composite section we have A + #### From which A + 15072 = 112903 / 1.2 or A = 79014 mm2 actual area = 80500 mm2 Hence provide a Ring beam size 350 x 230 mm f strirrups @ 300 mm c/c to tie ring beam. Provide 8 mm These ring are lapped with dome reinforcement as shown in fig. using 20
mm bars
A
=
4 Design of tank wall:- Since dome roof has been design on membrane the analysis, the tank wall may be assumed to be free on top and bottom, and the tank wall will be subjected to purely hoop stress. wHD 9800 x 4.00 x 11.60 = = 227360 N/m Maximum hoop tension at base= 2 2 2 1977 Area of ring = 227360 / 115 = or 989 mm2 both side mm 2 3.14xdia 3.14 x 12 x 12 using 12 mm bars A = = = 113 4 x100 4 x 100 Spacing of hoop Bars = 1000 x 113 / 989 = 114 say = 110 mm 12 mm F bar, @ 110 mm c/c in both direction. Hence Provided 1000 x 113 2 Actual , Ast = 2 x = 2055 mm 110 The spacing of ring may be increased towards the top, since pressure varies lineearly
2
mm
Using a tensile stress of 1.2N/mm2 for the the combined section , 227360 thickness T is given by= = 1.2 1000 T +( 13 1 )x 2055 From which 3xD +5 =
Minimum thickness Hence provided
=
170
T 3
= x
169 4
mm +
5
cm =
17
=
170
mm
mm thickness throughout the height, through the thickness at the top can be reuced.
Distribution reinforcement -
100
450 0.28 Distribution reinforcement area = x 100 Provide half the reinfocement near each face, Asd = 2 3.14xdia using 8 mm bars A = 4 x100 / The spacing of 8 mm f bars = 1000 x 50 Hence Provided 8 mm F bar, @
100
Asd
=
0.3
-
0.1
x
170
170
=
0.28
x
1000 =
%
476
mm
2
238 mm2 3.14 x 8 4 x 238 = 210 mm c/c 210 mm c/c =
5 D e s ig n o f B o t t o m d o m e : - for bottom dome h 2 = 2.20 m and its thickness = 200 mm R = 11.60 = R2 = (2r - rise) rise the radius r is given by x 2.20 x 2.20 )= 33.64 + 4.84 5.80 2= 2 2.20 Weight of water over the surface of dome is given by eq. 2 h2 D H x (3R2 - h2) Ww = P x w x 4 3 x 4.00 2.20 x( 3.00 11.60 = 3.14 x 9800 x 3 4 2946706 N = Total surface of Dome =2 p R2h2= 3.14 x 8.75 x 2.00 x 2.20 = 120.9 Self load of dome = 120.9 x 0.2 x 25000 = 604500 N/m2 = 2946706 N/m2
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x 8 100
=
50
/
=
5.80 m
2
)/
4.40 = 8.75
x
8.75 -
m
2.20 )
mm2
m
Load p2 per unit area = 5.8 = = sin f 8.75
0.663 p2R2
Maximum hoop stress at center =
2xt2 p2.R2
Maximum Maridian stress =
Total load = 3551206 N/m2 3551206 / 120.9 = 29373 N/m2 6.55 and = 0.75 or f '= 41 degree cos f = 8.75 29373 x 8.75 = = 642534 N/m2 = 0.643 N/mm 2 Safe 2 0.2 x 1- cos
f
2
t2 sin f 29373 x 8.75 1 - 0.749 = x = 735362 N/mm2 0.2 0.663 x 0.663 W2 3551206 Alternatively shear force F 2 = = = 97496 N/m 3.14 x 11.60 pD F2 97496 Meriditional thrust T 2 = = = 147084 N/m 0.663 sinf2 147084 Meriditional stress = = 0.735 N/mm2 1000 x 200 The stress are with in safe limit. However provide minimum reinforcement 200 100 x = 0.27 % Ast = 0.3 0.1 450 100 0.27 2 Distribution reinforcement area = x 200 x 1000 = 540 mm 100 2 3.14xdia 3.14 x 8 x 8 using 8 mm bars A = = = 50 4 x100 4 x 100 Spacing of hoop Bars = 1000 x 50 / 540 = 93 say = 90 mm 8 mm F bar, @ 90 mm c/c in both direction. Hence Provided The thickness of dome
Design of ring beam :-
=
Meridional thrust per metre length of dome at its base.= 735362 Horizontal component T per metre length .= 147072 cos 41 = Alternatively, p2 = F2 Cot f2 = #### x
\ hoop tension
=
110094
x
11.60 2
=
638545
2
mm
200 mm assumed x1
x
0.2
=
147072
N/m
147072
x
0.75 =
110094
N/m
1.129 =
110103
steel required =
638545
/
115 = 5553 mm2
2
mm bars
A
=
of area of cross section A is =A+(m-1)Ash=
A
+(
2
13 -
Allowing a stress of 1.2 N/mm in composite section we have From which
A + 67824 = Beam width =
Hence provide a Ring beam size Provide
Safe
3.14xdia 3.14 x 30 x 30 = = 707 mm2 4 x100 4 x 100 No.of hoop Bars = 5553 / 707 = 8 No. say 8 No. mm Ring bar, for symetry. F Hence Provided 8 No. 30 2 5652 = 8 x 707 = mm Equivelent area of composite section of beam
using 30
Actual , Ast
Safe
8 mm
550 x
f strirrups @
638545
/
550
1 =
A 1.2 or A Beam depth
)x 5652 = A+
67824
638545 = 1.2 + #### = 464297 mm2 = 850
actual area = 467500 mm2 200 mm c/c to tie ring beam. 850 mm
Alternatively, the above f bar verticaly provided @ above spacing on the inner face of the tank wall may betaken around the rings. Reinforcement shown in drawing
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DESIGN OF CIRCULAR WATER TANK (Domical top and base)
8 mm f 230
160 mm c/c 2000 11600
350
20 mm f Ring
4
12 mm f Bars
220
mm c/c
210
mm c/c
12 mm f Bars
110
mm c/c
30 mm f Bars 12 mm f 110 mm c/c 0
8
mm c/c
Nos
4000 8 mm f
0 mm f Ring 0 mm c/c 0 850
[email protected]
30 mm f Bars
8
mm c/c
0 mm f Ring
0
mm c/c both side 2.00 R= 5.80
F f
Fig 1
f
VALUES OF DESIGN CONSTANTS Grade of concrete Modular Ratio
M-15 18.67
M-20 13.33
M-25 10.98
M-30 9.33
M-35 8.11
M-40 7.18
scbc N/mm2 m scbc
5
7
8.5
10
11.5
13
93.33
93.33
93.33
93.33
93.33
93.33
kc
0.4
0.4
0.4
0.4
0.4
0.4
jc
0.867
0.867
0.867
0.867
0.867
0.867
Rc
0.867
1.214
1.474
1.734
1.994
2.254
Pc (%)
0.714
1
1.214
1.429
1.643
1.857
kc
0.329
0.329
0.329
0.329
0.329
0.329
jc
0.89
0.89
0.89
0.89
0.89
Rc
0.89 0.732
1.025
1.244
1.464
1.684
1.903
Pc (%)
0.433
0.606
0.736
0.866
0.997
1.127
kc
0.289
0.289
0.289
0.289
0.289
0.289
jc
0.904
0.904
0.904
0.904
0.904
0.904
Rc
0.653
0.914
1.11
1.306
1.502
1.698
Pc (%)
0.314
0.44
0.534
0.628
0.722
0.816
kc
0.253
0.253
0.253
0.253
0.253
0.253
jc
0.916
0.916
0.916
0.914
0.916
0.916
Rc
0.579
0.811
0.985
1.159
1.332
1.506
Pc (%)
0.23
0.322
0.391
0.46
0.53
0.599
(a) sst = 140 N/mm2 (Fe 250) (b) sst = 190 N/mm2 (c ) sst = 230 N/mm2 (Fe 415) (d) sst = 275 N/mm2 (Fe 500)
Permissible shear stress Table 100As bd
v
in concrete (IS : 456-2000)
Permissible shear stress in concrete tv N/mm M-15 M-20 M-25 M-30 M-35
2
M-40
< 0.15
0.18
0.18
0.19
0.2
0.2
0.2
0.25 0.50 0.75 1.00 1.25 1.50 1.75 2.00 2.25 2.50 2.75
0.22 0.29 0.34 0.37 0.40 0.42 0.44 0.44 0.44 0.44 0.44 0.44
0.22 0.30 0.35 0.39 0.42 0.45 0.47 0.49 0.51 0.51 0.51 0.51
0.23 0.31 0.36 0.40 0.44 0.46 0.49 0.51 0.53 0.55 0.56 0.57
0.23 0.31 0.37 0.41 0.45 0.48 0.50 0.53 0.55 0.57 0.58 0.6
0.23 0.31 0.37 0.42 0.45 0.49 0.52 0.54 0.56 0.58 0.60 0.62
0.23 0.32 0.38 0.42 0.46 0.49 0.52 0.55 0.57 0.60 0.62 0.63
3.00 and above
Maximum shear stress tc.max in concrete (IS : 456-2000) Grade of concrete
tc.max
M-15 1.6
M-20 1.8
M-25 1.9
M-30 2.2
M-35 2.3
M-40 2.5
Gra
t
Shear stress tc 100As bd
0.14 0.15 0.16 0.17 0.18 0.19 0.2 0.21 0.22 0.23 0.24 0.25 0.26 0.27 0.28 0.29 0.3 0.31 0.32 0.33 0.34 0.35 0.36 0.37 0.38 0.39 0.4 0.41 0.42 0.43 0.44 0.45 0.46 0.47 0.48 0.49 0.5 0.51 0.52 0.53 0.54 0.55 0.56 0.57 0.58 0.59 0.6 0.61
M-20
0.17 0.18 0.18 0.18 0.19 0.19 0.19 0.2 0.2 0.2 0.21 0.21 0.21 0.22 0.22 0.22 0.23 0.23 0.24 0.24 0.24 0.25 0.25 0.25 0.26 0.26 0.26 0.27 0.27 0.27 0.28 0.28 0.28 0.29 0.29 0.29 0.30 0.30 0.30 0.30 0.30 0.31 0.31 0.31 0.31 0.31 0.32 0.32
Reiforcement % M-20
0.17 0.18 0.19 0.2 0.21 0.22 0.23 0.24 0.25 0.26 0.27 0.28 0.29 0.30 0.31 0.32 0.33 0.34 0.35 0.36 0.37 0.38 0.39 0.4 0.41 0.42 0.43 0.44 0.45 0.46 0.46 0.47 0.48 0.49 0.50 0.51
modification factore Ta
100As bd
0.14 0.15 0.18 0.21 0.24 0.27 0.3 0.32 0.35 0.38 0.41 0.44 0.47 0.5 0.55 0.6 0.65 0.7 0.75 0.82 0.88 0.94 1.00 1.08 1.16 1.25 1.33 1.41 1.50 1.63 1.64 1.75 1.88 2.00 2.13 2.25
Degree 1 2 3 4 5 6
% fy 0.0 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9 3.0 3.1 3.2
Value of angle sin cos 0.017 1.000 0.035 0.999 0.052 0.999 0.070 0.998 0.087 0.996 0.104 0.995
200
1.90 1.80 1.70 1.60 1.55 1.50 1.50 1.45 1.40 1.35 1.35 1.30 1.30 1.25 1.25 1.20 1.18 1.17 1.16 1.15 1.14 1.13 1.12 1.11 1.11 1.11
tan 0.017 0.035 0.052 0.070 0.087 0.105
250
328
2.0 1.75 1.65 1.55 1.5 1.45 1.4 1.35 1.3 1.3 1.25 1.2 1.2 1.18 1.16 1.14 1.13 1.12 1.1 1.1 1.08 1.06 1.05 1.04 1.03 1.02 1.01 1.00
2 1.85 1.75 1.65 1.5 1.4 1.35 1.30 1.25 1.2 1.16 1.13 1.1 1.1 1.07 1.05 1.03 1.01 1.0 0.99 0.97 0.96 0.95 0.94 0.93 0.92 0.92 0.91 0.91 0.90 0.87 0.86
Degree 1 2 3 4 5 6
0.62 0.63 0.64 0.65 0.66 0.67 0.68 0.69 0.7 0.71 0.72 0.73 0.74 0.75 0.76 0.77 0.78 0.79 0.8 0.81 0.82 0.83 0.84 0.85 0.86 0.87 0.88 0.89 0.9 0.91 0.92 0.93 0.94 0.95 0.96 0.97 0.98 0.99 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 1.12 1.13
0.32 0.32 0.32 0.33 0.33 0.33 0.33 0.33 0.34 0.34 0.34 0.34 0.34 0.35 0.35 0.35 0.35 0.35 0.35 0.35 0.36 0.36 0.36 0.36 0.36 0.36 0.37 0.37 0.37 0.37 0.37 0.37 0.38 0.38 0.38 0.38 0.38 0.38 0.39 0.39 0.39 0.39 0.39 0.39 0.39 0.39 0.4 0.4 0.4 0.4 0.4 0.4
7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58
0.122 0.139 0.156 0.174 0.191 0.208 0.225 0.242 0.259 0.276 0.292 0.309 0.326 0.342 0.358 0.375 0.391 0.407 0.422 0.438 0.454 0.469 0.485 0.500 0.515 0.530 0.545 0.559 0.573 0.858 0.602 0.616 0.629 0.643 0.656 0.669 0.682 0.695 0.707 0.719 0.731 0.742 0.755 0.766 0.777 0.788 0.799 0.809 0.819 0.829 0.839 0.848
0.993 0.990 0.988 0.985 0.981 0.978 0.974 0.970 0.966 0.961 0.956 0.951 0.946 0.940 0.934 0.927 0.921 0.924 0.906 0.898 0.891 0.883 0.875 0.866 0.857 0.848 0.839 0.829 0.819 0.809 0.799 0.788 0.777 0.766 0.755 0.743 0.731 0.719 0.707 0.695 0.682 0.669 0.656 0.643 0.629 0.616 0.602 0.588 0.574 0.559 0.545 0.530
0.123 0.140 0.158 0.176 0.194 0.213 0.231 0.249 0.268 0.287 0.306 0.325 0.344 0.364 0.384 0.404 0.424 0.440 0.466 0.488 0.510 0.532 0.554 0.577 0.601 0.625 0.649 0.675 0.700 1.060 0.754 0.781 0.810 0.839 0.869 0.900 0.933 0.966 1.000 1.036 1.072 1.109 1.150 1.192 1.235 1.280 1.327 1.376 1.428 1.483 1.540 1.600
7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58
1.14 1.15 1.16 1.17 1.18 1.19 1.20 1.21 1.22 1.23 1.24 1.25 1.26 1.27 1.28 1.29 1.30 1.31 1.32 1.33 1.34 1.35 1.36 1.37 1.38 1.39 1.40 1.41 1.42 1.43 1.44 1.45 1.46 1.47 1.48 1.49 1.50 1.51
0.4 0.4 0.41 0.41 0.41 0.41 0.41 0.41 0.41 0.41 0.41 0.42 0.42 0.42 0.42 0.42 0.42 0.42 0.42 0.43 0.43 0.43 0.43 0.43 0.43 0.43 0.43 0.44 0.44 0.44 0.44 0.44 0.44 0.44 0.44 0.44 0.45 0.45
1.52 1.53 1.54 1.55 1.56 1.57 1.58 1.59 1.60 1.61 1.62 1.63 1.64
0.45 0.45 0.45 0.45 0.45 0.45 0.45 0.45 0.45 0.45 0.45 0.46 0.46
59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90
0.857 0.866 0.875 0.883 0.891 0.899 0.906 0.914 0.921 0.927 0.934 0.940 0.946 0.951 0.956 0.961 0.966 0.970 0.974 0.978 0.982 0.985 0.988 0.999 0.993 0.995 0.996 0.998 0.999 0.999 0.9998 1.000
0.515 0.500 0.485 0.470 0.454 0.438 0.423 0.407 0.391 0.375 0.358 0.342 0.326 0.309 0.292 0.276 0.259 0.242 0.225 0.208 0.191 0.174 0.156 0.139 0.122 0.105 0.087 0.070 0.052 0.035 0.017 0.000
1.664 1.732 1.804 1.880 1.963 2.051 2.145 2.246 2.356 2.475 2.605 2.747 2.904 3.078 3.271 3.488 3.732 4.011 4.332 4.705 5.145 5.673 6.315 7.178 8.145 9.517 11.431 14.302 19.083 28.637 57.295 1.000
59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90
Table Carpentors's coefficents Factors H+d A D / H f o e u l a V
0.2 0.3 0.4 0.5 1.0 2.0 4.0
F 10 0.046 0.032 0.024 0.02 0.012 0.006 0.004
20 0.028 0.019 0.014 0.02 0.006 0.003 0.002
30 0.022 0.014 0.01 0.009 0.005 0.002 0.002
40 0.015 0.01 0.007 0.006 0.003 0.002 0.001
10 0.55 0.5 0.45 0.37 0.3 0.27
1.65 1.66 1.67 1.68 1.69 1.70 1.71 1.72 1.73 1.74 1.75 1.76 1.77 1.78 1.79 1.80 1.81 1.82 1.83 1.84 1.85 1.86 1.87 1.88 1.89 1.90 1.91 1.92 1.93 1.94 1.95 1.96 1.97 1.98 1.99 2.00 2.01 2.02 2.03 2.04 2.05 2.06 2.07 2.08 2.09 2.10 2.11 2.12 2.13 2.14 2.15 2.16
0.46 0.46 0.46 0.46 0.46 0.46 0.46 0.46 0.46 0.46 0.47 0.47 0.47 0.47 0.47 0.47 0.47 0.47 0.47 0.47 0.47 0.47 0.47 0.48 0.48 0.48 0.48 0.48 0.48 0.48 0.48 0.48 0.48 0.48 0.48 0.49 0.49 0.49 0.49 0.49 0.49 0.49 0.49 0.49 0.49 0.49 0.49 0.49 0.50 0.50 0.50 0.50
2.17 2.18 2.19 2.20 2.21 2.22 2.23 2.24 2.25 2.26 2.27 2.28 2.29 2.30 2.31 2.32 2.33 2.34 2.35 2.36 2.37 2.38 2.39 2.40 2.41 2.42 2.43 2.44 2.45 2.46 2.47 2.48 2.49 2.50 2.51 2.52 2.53 2.54 2.55 2.56 2.57 2.58 2.59 2.60 2.61 2.62 2.63 2.64 2.65 2.66 2.67 2.68
0.50 0.50 0.50 0.50 0.50 0.50 0.50 0.50 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51
2.69 2.70 2.71 2.72 2.73 2.74 2.75 2.76 2.77 2.78 2.79 2.80 2.81 2.82 2.83 2.84 2.85 2.86 2.87 2.88 2.89 2.90 2.91 2.92 2.93 2.94 2.95 2.96 2.97 2.98 2.99 3.00 3.01 3.02 3.03 3.04 3.05 3.06 3.07 3.08 3.09 3.10 3.11 3.12 3.13 3.14 3.15
0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51
Permissible Bond stress Table de of conc bd
M-10 --
(N / mm
M-15 0.6
M-20 0.8
M-25 0.9
bd
in concrete (IS : 456-2000)
M-30 1
M-35 1.1
M-40 1.2
M-45 1.3
Development Length in tension Plain M.S. Bars
H.Y.S.D. Bars
Grade of concrete
tbd (N / mm2)
kd = Ld F
tbd (N / mm2)
M 15
0.6
58
0.96
60
M 20
0.8
44
1.28
45
M 25
0.9
39
1.44
40
M 30
1
35
1.6
36
M 35
1.1
32
1.76
33
M 40
1.2
29
1.92
30
M 45
1.3
27
2.08
28
M 50
1.4
25
2.24
26
kd = Ld
F
Permissible stress in concrete (IS : 456-2000) 2 Permission stress in compression (N/mm ) Permissible stress in bond (Average) for Grade of 2 Bending acbc Direct (acc) plain bars in tention (N/mm ) concrete 2 2 2 (N/mm2) (N/mm2) (N/mm2) in kg/m Kg/m Kg/m --M 10 3.0 300 2.5 250 0.6 60 M 15 5.0 500 4.0 400 0.8 80 M 20 7.0 700 5.0 500 0.9 90 M 25 8.5 850 6.0 600 1.0 100 M 30 10.0 1000 8.0 800 1.1 110 M 35 11.5 1150 9.0 900 1.2 120 M 40 13.0 1300 10.0 1000 1.3 130 M 45 14.5 1450 11.0 1100 140 16.0 12.0 1.4 M 50 1600 1200
Maximum shear stress tc.max in concrete (IS : 456-2000) Grade of concrete
tc.max
M-15 1.6
M-20 1.8
M-25 1.9
M-30 2.2
M-35 2.3
M-40 2.5
le 415
1.90 1.80 1.70 1.60 1.50 1.40 1.30 1.20 1.15 1.05 1.02 1.20 0.98 0.96 0.94 0.92 0.91 0.90 0.89 0.86 0.86 0.85 0.84 0.83 0.83 0.82 0.82 0.81 0.81 0.81 0.81 0.81 0.81 0.81
500 2.00 1.80 1.65 1.50 1.40 1.35 1.30 1.20 1.16 1.08 1.00 0.95 0.90 0.86 0.84 0.82 0.81 0.80 0.79 0.78 0.77 0.76 0.75 0.74 0.73 0.72 0.72 0.72 0.71 0.71 0.71 0.70 0.70 0.69 0.69 0.68 0.68
sin 0.017 0.035 0.052 0.070 0.087 0.104
Degree 1 2 3 4 5 6
0.122 0.139 0.156 0.174 0.191 0.208 0.225 0.242 0.259 0.276 0.292 0.309 0.326 0.342 0.358 0.375 0.391 0.407 0.422 0.438 0.454 0.469 0.485 0.500 0.515 0.530 0.545 0.559 0.573 0.588 0.602 0.616 0.629 0.643 0.656 0.669 0.682 0.695 0.707 0.719 0.731 0.742 0.755 0.766 0.777 0.788 0.799 0.809 0.819 0.829 0.839 0.848
7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58
0.857 0.866 0.875 0.883 0.891 0.899 0.906 0.914 0.921 0.927 0.934 0.940 0.946 0.951 0.956 0.961 0.966 0.970 0.974 0.978 0.982 0.985 0.988 0.999 0.993 0.995 0.996 0.998 0.999 0.999 0.9998 1.000
59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90
or cylenlidrical tank (Reyolndhand book) K1 20 0.5 0.43 0.39 0.37 0.28 0.22 0.2
K2 30 0.45 0.38 0.35 0.32 0.24 0.19 0.17
40 0.4 0.33 0.3 0.27 0.21 0.16 0.14
10 0.32 0.35 0.44 0.48 0.62 0.73 0.8
20 0.46 0.53 0.58 0.63 0.73 0.81 0.85
30 0.53 0.6 0.65 0.69 0.74 0.85 0.87
40 0.5 0.66 0.7 0.73 0.83 0.88 0.9
M-50 1.4 fs = 120 =fy200
2.0
fs =145 =fy250 fs =190 =fy328
1.6
fs =240 =fy415 fs = 290 =fy500
1.2 0.8 0.4
0
0.4
0.8
1.2
1.6
2.0
Modification factore Fig 7.1 Fs= steel stress of service load =0.58fy for steeel f y 500
= Fs 290 N/mm
2
f y 415
= Fs 240 N/mm
2
f y 328 f y 250
= Fs 190 N/mm 2 = Fs 145 N/mm
f y 207
= Fs 120 N/mm
2
2
2.4
2.8
3.2
