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1 Length of cantilever roof each side 3.00 mtr bw 400 mm
3 Clear span 6.00 mtr 6000 mm
4 Super imposed Load 2.00 kN/m2
5 Conrete M - m - 20 Grade 25000 N/m3
scbc 7 N/mm2 m 13.33
6 Steel fy 415 N/mm2 230 N/mm2
7 Nominal cover 15 mm 25 mm
8 Reinforcement Beam
Bottom Main reinforcement 30 mm F 5 Nos bars
Top holding bars 12 mm F 3 Nos bars
2 lgd Stirrups 8 mm F 220 mm c/c
Reinforcement slab
main bars at supports 10 mm F 140 mm c/c
main bars at end 10 mm F 280 mm c/c
Distrbution at supports 8 mm F 140 mm c/c
Distrbution at ends 8 mm F 210 mm c/c
3 nos. holding bars
30 mm f 12 mm f 30 mm f
2 Nos bars 2 Nos bars
mm mm
860 30 mm f main 5 Nos bars 860
(A) Section at beam
10 mm f @ 10 mm f @ 12 mm f @
280 mmc/c 140 mm c/c 3 Nos bars
3000 3000
100
290 mm
8 mmf @ 8 mmf @ 8 mm f @
mm c/c 140 mm c/c 220 mm c/c 2 lgd stirrups
500
mm 30 mm f @
5 Nos bars
210
220220
Tensile stress
(B) Section at mid - span
400
6000
Design of Cycle stand shade
pkn
Effective cover
Unit weight concrete
Name of work:-
`
Name of work:-
1 Length of cantilever roof each side 3.00 mtr 3000 mm bw 400 mm
3 Clear span 6.00 mm 6000 mm
4 Super imposed load 2.00 kN/m 2000 N/m
5 Concrete m 20 Unit weight concrete N/m3
scbc 7 N/mm2
m 13.3
6 Steel fy 415 N/mm2
Tensile stess = 230 N/mm2
7 Nominal cover 15 mm Effective cover = 25 mm
Solution :-
For m 20 concrete we have
scbc = 7 N/mm2
m = 13.3 sst = 230 N/mm2,
mc x
mc + t 13.33 x 7 + 230
j = 1 - k/3 = 1 - 0.29 / 3 = 0.904
R=1/2xc x j x k = 0.5 x 7 x 0.904 x 0.289 = 0.913
(A) Design of cantilever slab
= 7
20 concrete =0.44% . Assuming pt =0.25
1.6 7 x 1.6 = 11.2
span 3000
11.2 11.2
100 mm at ends. Mean thickness of slab( 290 + 100 )/ 2 = 195 mm
15 mm nominal cover and using 10 mm f bars,
available d = 290 - 15 - 10 / 2 = 270 mm at supports
and d = 100 - 15 - 10 / 2 = 80 mm at free ends
0.195 x 1.0 x 1 x 25000 = N
= N/m2
\ = N/m2
wL2 6875 x 3.000 x 3.000
2
V = wL = 6875 x 3.000 = N/m
width considering b=1 meter =1000 mm
BM = 30938 x 1000
Rxb 0.913 x 1000
x
230 x 0.904 x 270
3.14xdia2
3.14 x 10 x 10
4 x100 4 x
1000 x 79 / 551 = 142 mm
Hence Provided 10 mm F bar, @ 140 mm c/c
a f 1000 x 78.5
s
1000 x 270
Let us curtail alternate bars at half the cantilever length.
wx2 6875 x 1.5
2 2
pkn
Design of Cycle stand shade
Spacing of Bars =
Actual area of stell provided =1000 =
x 10'67.73=
A*1000/Ast =
A = = =
N-mm
sst x jx D
using 10 mm bars 78.5 mm2
100
551
= mm184
140= 561 mm
2
mm2
N-mm/m
20625
Effective depth required =
Ast =BM
=30938.00 1000
=
M = =2
= 30938
keeping
Dead load of slabper sq meter = 4875
super imposed load 2000
Total load /m2 6875
= 290 mmmm keep total depth of 268 + 15
= =13.33 7
25000
=kc 0.29=
and reduce it to
For stiffness the ratio of span to effective depth of cantilever
For a balanced design, the percentage reinforcement for m =
\ span/d=We get, from fig 1. modification factore, using fe 415 steel. =
\ Effective depth = = = 268
561
k
1000
=pt =
= =B.M. at the point 2x
x %100 0.21
270 + 80
x
230 x 0.904 x 175
1
2
Check for shear V
bxd 1000 x 270
0.12 x 1000 x 290
3.14xdia2
3.14 x 8 x 8
4 x100 4 x
1000 x 50 / 348 = 144 mm
Hence Provided 8 mm F bar, @ 140 mm c/c
At the half the cantilever length, avrage depth '= 195 mm
0.12 x 1000 x 195
3.14xdia2
3.14 x 8 x 8
4 x100 4 x
1000 x 50 / 234 = 215 mm
Hence Provided 8 mm F bar, @ 210 mm c/c
(B) Design of beam :-
The beam will be designed as T-beam with tapered flanges of uniform average thickness.
Width of web, bw = L / 10 or width of column which is heigher
bw = 3.00 / 10 = 0.30 m width of column = 0.40 m here mtr
290 + 100
Total width of flange = b = 2 x 3 + 0.40 = 6.40 mm
= lo = 2 x 3 + 0.40 = 6.40 mtr or mm
For an isolated T-Beam,the width of the flange is
lo 6400
b 6400
400 mm, equal the bw, for the purpose of calculating the dead load
(I) Dead load of slab = 0.195 x 1 x 6 x #### = N
(II) Dead load of beam = 0.40 x 0.40 x 1 x #### = N
(III) Super imposed load = 2000 x 6.40 x 1 = N
= N
wlo2 46050 x 6.4 x 6.4 x 1000
8
Effective depth of beam:-
2x 0.289 d- 195
2 x 0.289 d- 195
0.45 x 1680 x 7.00 x
390 d - = 44553 + or
= / or mm
keep D = 500 mm 30 8 mm f bars, [email protected]
=Asd 100
= mm2
mm2
100
Hence O.K.mm2
=20625
N/mm2 which is quite small= 0.08
561 =x
Ast =
Actual Ast available =
Effective depth of slab
BM =
= = mm2
175
10'6
=
Ast =0.12xbD
280 213
213 mm2
>
7.73
sst x jx D
348
Ast = mm2
Asd 100
A*1000/Ast =
tv =
using 8
Distribution reinforcement
234
=
0.12xbD=
A = =
Spacing of Bars =
= = 50.2using 8
50.2mm bars
mm bars A
=
2= 195=Avrage depth of flange, Df
mm2
100
Spacing of Bars = A*1000/Ast =
=
=
6400
mm = 0.195 mtr
Let effective span of beam
bf =+ 4
lo
+ 4
12800
46050Total w
M = = =8
Assume over all depthof beam
29250
4000
+ 400 = 1680+ bw6400
=
x 1680 x
for balance section, we have
or 0.45
M
= 7
keeping
195
mm nominal cover and using
675.66
131753
176306
176306
390 452
=
235776000
235776000=0.289
2kcd-Df
kc
235776000
0.45bf.c.Df
x
0.40
mm
6400mtr or
N-mm
available d = 500 - 30 - 8 - 30 / 2 = 447 mm
= 0.50 x 0.40 x 1 x #### = N
= 29250 + 5000 + 12800 = N
wlo2 47050 x 6.4 x 6.4 x 1000
8
Df 195
2 2
230 x 0.904 x 350
3.14xdia2
3.14 x 30 x 30
4 x100 4 x
= 3311 x 707 = 5 No.
= 5 No. 30 mm F bar, = 3535 mm2
Determination N.A.and actual stresses.
1680 13.33 x 3535 x( 447 - n)
2
\ n2 = 25075 - 56.1 n or n
2+ n - = 0
or n = 56.10 + 3147 -4x 1.00 x
2 a 2 x 1
or n = 56.10 +( 3147 - )1/2
2
or n = 56.10 +( )1/2
2 x 1
or n = 56.10 + 322
2
or n = 266 / 2 = 133 mm
n 133
3 3
m
Ast xa 3535 x 403
t n 169 N
m d - n 13.3 447 - 133 mm2
Shear reinforcement:-
wl 47050 x 6.00 V = N
2 2 bxd 400 x 447 mm2
100As 100 x 2121
bxd 400 x 447
Hence from Table permissible shear (tc)for M 20 concrete, for 1.19 % steel = 0.41 N/mm2
> tc Shear reinforcement necessary
20 Concrete, tcmax. = 1.80 N/mm2 < than Tc section O.K.
Shear reinfocement will be provided both in the form of inclined bars as well as in the form of vertical stirrups.
Out of 5 30 mm f bars, let us bend 2 bars at distance of √2 a = √ 2 x 403 mm
= 1.414 x 403 = 570 mm from the edge of the supports.
3.14xdia2
3.14 x 30 x 30
4 x
= 2 x 707 = 1414 mm2
\ Shear resistance of 2 bent up bars = v1 sin 45
v1 = ssv x Asv x sina = 230 x 1414 x 0.71 = N
more than the S.F. it self. Through shear esistance of concrete (v2 = tc. bd )
is additionally available, we will have to provide nominal shear stirrups.
3.14 x 8 x 8
4 x
using 8 mm 2 lgd stirrups area = 2 x 50.2 = mm2
100.4
V=
4 x100bend up bars 2Area of cross -section of
Since tv
mm2
100
Also from table for M- Since tv
= =
M = =
Revised Dead load of beam
8
Total weight w
240896000=
5000
N-mm
47050
350 mm= d = 447-
Ast =BM
=sst x jx D
- =
mm bars A
= 3311
Approximate L.A., a
mm2240896000
mm2
100
Noumber of Bars
25075
= = = 707using 30
-25075
Hence Provided Actual steel provide
(n)2=
56.10
Assuming that N.A. falls in the flange, we have N.A. =
447
-100301.585
103448.47
= 403 mm
=240896000
x
-
n =b +b
2-4.a.c
d -L.A.= =
230<
1337
corresponding stress In
concrete is given by =
= 169Avrage stress in steel =
<
= 141150141150
O.K.
= x = 5.4
N/mm2
%
=N tv =
= 1.19bars will be bent up available
using 8
0.79
707
Area of cross -section of
229931
This is
Assuming that at the ends, 2
mm2mm bars area
4 x100
3.14xdia2
= = = 50.2100
2.18 x 100 x 415
Hence Provided 8 220 860 mm from edge of supports
141150
3.00
= 0.41 x 400 x 447 = N
Hence shear to be rasisted by stirrups is given by Vs =V-tc*bw*d = - =
ssv.Asv.d 230 x 100.4 x 447
227 mm. Hence provide 8 mm f stirrups @ 220 mm
3 x 12
check for development length at the end.
1.3xM1 L0
V
M1 = moment of resistance of section, assuming all reinforcement stress at sst
M1 "= Ast x s st x jc x d
2121 x 230 x 0.904 x 447
V = 141150 N Ls = 0 Alternatively, Ld = 45 F = 45 x 30 = 1350 mm
400 mm and a side cover x' 30 mm,
And Provide 900 bend at the ends
Ls 400
2 2
f .sst x
4.tbd 4 x 0.8 x 2
1.3 xM1 197.1 x 10 6
V
= 2075 > 1350
Vs=
27379
100687 N0.86 )=
But maximum spacing can not exceed
100687 73308 27379
= 377 mmThe spacing of 8 mm f 2 lgd stirrups is, sv =
At
73308shear resistance of concrete =tc.bw.d
mm F 2 lgd stirrups, @ mm c/c upto
860 mm shear force x( 3.00 -
the maximum spacing of stirrups is given by 227
30 + 90
mm2.175 x Asv.x fy
b=
400=
we have, Lo =( - x'
Ld
mm
>
f = 45230
mm
+ L0 = 1.3 x + 260
+ 3 x f
=141150
mm2075
= 260= -
Hence Code requirement are satisfied
The code requires that + 2121
Ld = = = 45 1350
Let us assume the width of supports equal to
N-mm1000000
= 197.1 x 10 6
mm f holding bars at topProvidethrough out the length of beam.
f x 30 =
mm2Ast available at end.
=
#
mm F 2 - lgd strirrups @ mm c/c
3 - mm F holding bars 2 - mm F bars
mm mm
- mm F bars
mm f @ mm f @ 3 - mm F holding bars
Nos bars mm c/c
mm
mmf @ mmf @
mm c/c mm c/c mm F 2 - lgd strirrups @ mm c/c
- mm F bars
mm
500
mm
500
1500
3000
860
100
290
220 220
5
400
1500
30 860
10
280
10
140
140
8 8
210
pkn
2208
12 30
5 30
12
8 220
M-15 M-20 M-25 M-30 M-35 M-40 Grade of concrete
18.67 13.33 10.98 9.33 8.11 7.18 tbd (N / mm2)
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 0.89
Rc 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
M-15 M-20 M-25 M-30 M-35 M-40
0.18 0.18 0.19 0.2 0.2 0.2
0.22 0.22 0.23 0.23 0.23 0.23
0.29 0.30 0.31 0.31 0.31 0.32
0.34 0.35 0.36 0.37 0.37 0.38
0.37 0.39 0.40 0.41 0.42 0.42
0.40 0.42 0.44 0.45 0.45 0.46
0.42 0.45 0.46 0.48 0.49 0.49
0.44 0.47 0.49 0.50 0.52 0.52
0.44 0.49 0.51 0.53 0.54 0.55
0.44 0.51 0.53 0.55 0.56 0.57
0.44 0.51 0.55 0.57 0.58 0.60
0.44 0.51 0.56 0.58 0.60 0.62
0.44 0.51 0.57 0.6 0.62 0.63
M-15 M-20 M-25 M-30 M-35 M-40
1.6 1.8 1.9 2.2 2.3 2.5
Grade of concrete
tc.max
2.50
2.753.00 and above
(3) Maximum shear stress tc.max in concrete (IS : 456-2000)
2.00
2.25
1.50
1.75
1.00
1.25
0.50
0.75
0.25
bd
< 0.15
(2) Permissible shear stress Table tv in concrete (IS : 456-2000)
100As Permissible shear stress in concrete tv N/mm2
(d) sst =
275
N/mm2
(Fe 500)
(c ) sst =
230
N/mm2
(Fe 415)
(b) sst =
190
N/mm2
(a) sst =
140
N/mm2
(Fe 250)
(1) VALUES OF DESIGN CONSTANTS
Grade of concrete
Modular Ratio
scbc N/mm2
m scbc
100As 100As
bd bd Degree sin cos tan
0.15 0.18 0.18 0.15 10 0.17 0.98 0.18
0.16 0.18 0.19 0.18 11 0.19 0.98 0.19
0.17 0.18 0.2 0.21 12 0.21 0.98 0.21
0.18 0.19 0.21 0.24 13 0.23 0.97 0.23
0.19 0.19 0.22 0.27 14 0.24 0.97 0.25
0.2 0.19 0.23 0.3 15 0.26 0.97 0.27
0.21 0.2 0.24 0.32 16 0.28 0.96 0.29
0.22 0.2 0.25 0.35 17 0.29 0.96 0.31
0.23 0.2 0.26 0.38 18 0.31 0.95 0.32
0.24 0.21 0.27 0.41 19 0.33 0.95 0.34
0.25 0.21 0.28 0.44 20 0.34 0.94 0.36
0.26 0.21 0.29 0.47 21 0.36 0.93 0.38
0.27 0.22 0.30 0.5 22 0.37 0.93 0.40
0.28 0.22 0.31 0.55 23 0.39 0.92 0.42
0.29 0.22 0.32 0.6 24 0.41 0.92 0.45
0.3 0.23 0.33 0.65 25 0.42 0.91 0.47
0.31 0.23 0.34 0.7 30 0.50 0.87 0.58
0.32 0.24 0.35 0.75 35 0.57 0.82 0.70
0.33 0.24 0.36 0.82 40 0.64 0.77 0.84
0.34 0.24 0.37 0.88 45 0.71 0.71 1.00
0.35 0.25 0.38 0.94 50 0.77 0.64 1.19
0.36 0.25 0.39 1.00 55 0.82 0.57 1.43
0.37 0.25 0.4 1.08 60 0.87 0.50 1.73
0.38 0.26 0.41 1.16 65 0.91 0.42 2.14
0.39 0.26 0.42 1.25
0.4 0.26 0.43 1.33
0.41 0.27 0.44 1.41
0.42 0.27 0.45 1.50
0.43 0.27 0.46 1.63
0.44 0.28 0.46 1.64
0.45 0.28 0.47 1.75
0.46 0.28 0.48 1.88
0.47 0.29 0.49 2.00
0.48 0.29 0.50 2.13
0.49 0.29 0.51 2.25
0.5 0.30
0.51 0.30
0.52 0.30 % fy 200 250 328 415
0.53 0.30 0.0
0.54 0.30 0.05
0.55 0.31 0.10
0.56 0.31 0.15 1.90
0.57 0.31 0.20 1.80
0.58 0.31 0.25 2 1.70
0.59 0.31 0.30 1.85 1.60
0.6 0.32 0.35 1.75 1.50
0.61 0.32 0.4 1.65 1.40
0.62 0.32 0.5 2.0 1.5 1.30
modification factore Table
Value of angle
Shear stress tc Reiforcement %
M-20 M-20
0.63 0.32 0.6 1.75 1.4 1.20
0.64 0.32 0.7 1.90 1.65 1.35 1.15
0.65 0.33 0.8 1.80 1.55 1.30 1.05
0.66 0.33 0.9 1.70 1.5 1.25 1.02
0.67 0.33 1.0 1.60 1.45 1.2 1.20
0.68 0.33 1.1 1.55 1.4 1.16 0.98
0.69 0.33 1.2 1.50 1.35 1.13 0.96
0.7 0.34 1.3 1.50 1.3 1.1 0.94
0.71 0.34 1.4 1.45 1.3 1.1 0.92
0.72 0.34 1.5 1.40 1.25 1.07 0.91
0.73 0.34 1.6 1.35 1.2 1.05 0.90
0.74 0.34 1.7 1.35 1.2 1.03 0.89
0.75 0.35 1.8 1.30 1.18 1.01 0.86
0.76 0.35 1.9 1.30 1.16 1.0 0.86
0.77 0.35 2.0 1.25 1.14 0.99 0.85
0.78 0.35 2.1 1.25 1.13 0.97 0.84
0.79 0.35 2.2 1.20 1.12 0.96 0.83
0.8 0.35 2.3 1.18 1.1 0.95 0.83
0.81 0.35 2.4 1.17 1.1 0.94 0.82
0.82 0.36 2.5 1.16 1.08 0.93 0.82
0.83 0.36 2.6 1.15 1.06 0.92 0.81
0.84 0.36 2.7 1.14 1.05 0.92 0.81
0.85 0.36 2.8 1.13 1.04 0.91 0.81
0.86 0.36 2.9 1.12 1.03 0.91 0.81
0.87 0.36 3.0 1.11 1.02 0.90 0.81
0.88 0.37 3.1 1.11 1.01 0.87 0.81
0.89 0.37 3.2 1.11 1.00 0.86 0.81
0.9 0.37
0.91 0.37
0.92 0.37
0.93 0.37
0.94 0.38
0.95 0.38
0.96 0.38
0.97 0.38
0.98 0.38
0.99 0.38
1.00 0.39
1.01 0.39
1.02 0.39
1.03 0.39
1.04 0.39
1.05 0.39
1.06 0.39
1.07 0.39
1.08 0.4
1.09 0.4
1.10 0.4
1.11 0.4
1.12 0.4
1.13 0.4
1.14 0.4
1.15 0.4
1.16 0.41
1.17 0.41
1.18 0.41
1.19 0.41
1.20 0.41
1.21 0.41
1.22 0.41
1.23 0.41
1.24 0.41
1.25 0.42
1.26 0.42
1.27 0.42
1.28 0.42
1.29 0.42
1.30 0.42
1.31 0.42
1.32 0.42
1.33 0.43
1.34 0.43
1.35 0.43
1.36 0.43
1.37 0.43
1.38 0.43
1.39 0.43
1.40 0.43
1.41 0.44
1.42 0.44
1.43 0.44
1.44 0.44
1.45 0.44
1.46 0.44
1.47 0.44
1.48 0.44
1.49 0.44
1.50 0.45
1.51 0.45
1.52 0.45
1.53 0.45
1.54 0.45
1.55 0.45
1.56 0.45
1.57 0.45
1.58 0.45
1.59 0.45
1.60 0.45
1.61 0.45
1.62 0.45
1.63 0.46
1.64 0.46
1.65 0.46
1.66 0.46
1.67 0.46
1.68 0.46
1.69 0.46
1.70 0.46
1.71 0.46
1.72 0.46
1.73 0.46
1.74 0.46
1.75 0.47
1.76 0.47
1.77 0.47
1.78 0.47
1.79 0.47
1.80 0.47
1.81 0.47
1.82 0.47
1.83 0.47
1.84 0.47
1.85 0.47
1.86 0.47
1.87 0.47
1.88 0.48
1.89 0.48
1.90 0.48
1.91 0.48
1.92 0.48
1.93 0.48
1.94 0.48
1.95 0.48
1.96 0.48
1.97 0.48
1.98 0.48
1.99 0.48
2.00 0.49
2.01 0.49
2.02 0.49
2.03 0.49
2.04 0.49
2.05 0.49
2.06 0.49
2.07 0.49
2.08 0.49
2.09 0.49
2.10 0.49
2.11 0.49
2.12 0.49
2.13 0.50
2.14 0.50
2.15 0.50
2.16 0.50
2.17 0.50
2.18 0.50
2.19 0.50
2.20 0.50
2.21 0.50
2.22 0.50
2.23 0.50
2.24 0.50
2.25 0.51
2.26 0.51
2.27 0.51
2.28 0.51
2.29 0.51
2.30 0.51
2.31 0.51
2.32 0.51
2.33 0.51
2.34 0.51
2.35 0.51
2.36 0.51
2.37 0.51
2.38 0.51
2.39 0.51
2.40 0.51
2.41 0.51
2.42 0.51
2.43 0.51
2.44 0.51
2.45 0.51
2.46 0.51
2.47 0.51
2.48 0.51
2.49 0.51
2.50 0.51
2.51 0.51
2.52 0.51
2.53 0.51
2.54 0.51
2.55 0.51
2.56 0.51
2.57 0.51
2.58 0.51
2.59 0.51
2.60 0.51
2.61 0.51
2.62 0.51
2.63 0.51
2.64 0.51
2.65 0.51
2.66 0.51
2.67 0.51
2.68 0.51
2.69 0.51
2.70 0.51
2.71 0.51
2.72 0.51
2.73 0.51
2.74 0.51
2.75 0.51
2.76 0.51
2.77 0.51
2.78 0.51
2.79 0.51
2.80 0.51
2.81 0.51
2.82 0.51
2.83 0.51
2.84 0.51
2.85 0.51
2.86 0.51
2.87 0.51
2.88 0.51
2.89 0.51
2.90 0.51
2.91 0.51
2.92 0.51
2.93 0.51
2.94 0.51
2.95 0.51
2.96 0.51
2.97 0.51
2.98 0.51
2.99 0.51
3.00 0.51
3.01 0.51
3.02 0.51
3.03 0.51
3.04 0.51
3.05 0.51
3.06 0.51
3.07 0.51
3.08 0.51
3.09 0.51
3.10 0.51
3.11 0.51
3.12 0.51
3.13 0.51
3.14 0.51
3.15 0.51
Grade of concreteM-10 M-15 M-20 M-25 M-30 M-35 M-40 M-45
tbd (N / mm2) -- 0.6 0.8 0.9 1 1.1 1.2 1.3
M 15
M 20
M 25
M 30
M 35
M 40
M 45
M 50
(N/mm2) Kg/m2 (N/mm2) Kg/m
2
M 10 3.0 300 2.5 250
M 15 5.0 500 4.0 400
M 20 7.0 700 5.0 500
M 25 8.5 850 6.0 600
M 30 10.0 1000 8.0 800
M 35 11.5 1150 9.0 900
M 40 13.0 1300 10.0 1000
M 45 14.5 1450 11.0 1100
M 50 16.0 1600 12.0 1200 1.4 140
1.2 120
1.3 130
1.0 100
1.1 110
0.8 80
0.9 90
-- --
0.6 60
(N/mm2) in kg/m2
Grade of
concrete
Permission stress in compression (N/mm2) Permissible stress in bond (Average) for
plain bars in tention (N/mm2)Bending acbc Direct (acc)
1.3 27 2.08
Permissible stress in concrete (IS : 456-2000)
1.4 25 2.24 26
1.1 32 1.76 33
1.2 29 1.92 30
28
39 1.44 40
1 35 1.6 36
0.6 58 0.96 60
0.8 44 1.28 45
0.9
Development Length in tension
Grade of
concrete
Plain M.S. Bars H.Y.S.D. Bars
tbd (N / mm2) kd = Ld F tbd (N / mm2) kd = Ld F
Permissible Bond stress Table tbd in concrete (IS : 456-2000)
tan Degree sin cos
0.18 10 0.17 0.98
0.19 11 0.19 0.98
0.21 12 0.21 0.98
0.23 13 0.23 0.97
0.25 14 0.24 0.97
0.27 15 0.26 0.97
0.29 16 0.28 0.96
0.31 17 0.29 0.96
0.32 18 0.31 0.95
0.34 19 0.33 0.95
0.36 20 0.34 0.94
0.38 21 0.36 0.93
0.40 22 0.37 0.93
0.42 23 0.39 0.92
0.45 24 0.41 0.92
0.47 25 0.42 0.91
0.58 30 0.50 0.87
0.70 35 0.57 0.82
0.84 40 0.64 0.77
1.00 45 0.71 0.71
1.19 50 0.77 0.64
1.43 55 0.82 0.57
1.73 60 0.87 0.50
2.14 65 0.91 0.42
500
2.00
1.80
1.65
1.50
1.40
1.35
1.30
1.20
1.16
1.08
modification factore Table
Value of angle
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
M-50
1.4
0.0
Percentage of tension reinforcement
2 2.4 2.80.4 0.8 1.2 1.6
2.0
0.4
1.4
1.2
0.8
Modific
ation facto
rePermissible Bond stress Table tbd in concrete (IS : 456-2000)