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TRANSCRIPT
APPENDIX A
STUDIES ON SIMPLY SUPPORTED ONE WAY SLABS
A.I Computation of Ductility Factor
A.I.I Model calculation for the specimen SOSCll
Ductility factor = Deflection at ultimate load (Bu) / Deflection at yield load (By),ll =Ol/lOy (A.l)
Ultimate load, p" =23.78kN
Deflection at ultimate load, 01/ =32.00mm
Yield load Py is calculated as given below:
hk =42.15N / mm2
1;, =443N / mm2
Breadth of section, b =1000mmd =D -15 =60 -15 =45mm
A / =8x 1r X 62 =226. 194mm2
s 4
Esm=Ec
2.05 x 105 2.05 X 105
=5000 X ~fCk =5000x .J42.l5 == 6.315
bXxx~=mAs/Cd -x)
1000 x xx x = 6.315x 226.194x (45 -x)2
=> x= 9.99mm
bx3
d)2I =-+mA./( -xcr 3 ..
1000 x 9.9993
= 3 +6.315 x 226.194x (45 -9.999)2 =2.08x 106 mm4
/, = I" =m My (d -x)y Js I
cr
M443 =6.315x y 6 x(45-9.999)
2.08xl0
(A.2)
CA.3)
(A.4)
(A.S)
183
:::=> My =4168821.0S6Nmm =4.l7kNm
P 12
M =-y-y 8
P =4.17x8 =14.826kN/m 2
y 1.S 2
Py =14.826 x 1.5 xl =22.24kN
Py =22.24kN
Deflection at yield load, 5y == 19.6Sm
Therefore ductility factor, J.l = 5u =1.635y
A.2 Computation of First Crack Load
A.2.1 Model calculation for SOSCll
(a) By IS 456:2000
fek =42.lSN / mm 2
Overall depth, D =60mmD
y=-=30mm2
Gross moment of inertia, I gr = bD3
= 18000000mm4
12
Modulus of rupture, fer =0.7~fek
= O.7x.J42.1S = 4.S44N /mm 2
1= l.Sm
M = feJgrer
y
= 4.S44x 18000000 =2726767Nmm =2.726kNm30
M = Perl2
er 8
=8x 2.726 =9 692kN/ 2:::::> Per 2 • m1.S
First crack load, Per = Per X 1X 1.S = 14.54kN
(A.6)
(A.7)
(A.8)
(A.9)
(A.10)
(A.lI)
184
(b) By ACI 318 :2008
fck = 42.15N I mm2
I gr = 18000000mm4
[= 1.5my=30mm
Cylinder strength, f: = 0.8fek = 0.8x42.15 = 33.72N Imm 2
Modulus of rupture, fer = 0.62..J7: = 0.62 X .J33.72 = 3.60
C k· M t M leJgr 3.60x18000000 216'-'AT.rac mg omen, er =-= = . IWvmy 30
=8Mer =8x2.16=77kNI 2Per [2 1.5 2 • m
First crack load, Py =wx 1x 1.5 = 11.55kN
A.3 Computation of Theoretical Ultimate Moment
A.3.t By Henager and Doherty method adopted by ACI (Fig. 2.10)
(a) Model calculation of slabs with fibre for the specimen SOSC21
lek =47.24N I mm 2
For fibre reinforced concrete, cylinder strength f'e = 0.91ek = 42.516N Imm2
AS1 =226.19mm 2
f y =443N I mm2
Bond efficiency of fibre, Fbe =1
Aspect ratio of fibre, AJ =50
• •• O"J 2'rd Fbe AJTenstle stram m steel fibre, &s(jibres) =- =------"-Es Es
=2x 2.3x Ix 50 =0.001152.05x 105
333x 0,454x 9.81Bond stress, 'rd = 333psi = - = 2.3N I mm2
25,4x25,4
0.003 &s(jibres)--=-....,;.;..--'--C e-c
e =1.383c
(A.l2)
(A.B)
(A. 14)
(A.l5)
(A.I6)
(A. 17)
(A.I8)
185
M = A f (d - a)+a b(h-e)(h +.:._ a) (A.19)u .vy 2 I 222
Length of fibres, / =25mmDiameter of fibre, dI =0.5mm
Volume fraction of fibre, PI =0.5
Effective depth, d =45mmBreadth of section, b = 1000Overall depth, h =60
a = 0.00772-/ F, = 0.00772x25x 0.5x 1= 0.19 (A.20)I d
lPI be 0.5
P= 0.85 _(I: -27.6)x 0.05 = 0.7417 (A.21)6.89
a= A.Jy = 226.19x443 =3.1773 (A.22)PI:b 0.7417x42.516xl000
c:=:!!... = 3.1773 = 4.2835 (A.23)P 0.7417
e :=: 1.383c = 1.383 X 4.2835 = 5.9255
M = 226.19X443(45- 3.1773)+0.193XI000X(60-5.9255)(60 + 5.9255 _ 3.1773)u 2 2 2 2
:=: 4677340.978Nmm =4.68kNm
(b) Model calculation of slabs without fibre for the specimen SOSCll
hk =42.15N / mm2
As, =226.19mm2
I y =443N / mm2
b:=: 1000mmd:=: 45mmcylinder strength of concrete without fibre, I: =0.8/ck
=0.8x42.15 =33.72N /mm 2
p:=: 0.85 _(I: -27.6)x 0.05 = 0.85_(33.72-27.6)x 0.05 = 0.80556.89 6.89
:=: Asly = 226.19 x 443 = 3.689a fJf:b 0.8055x33.72xl000
M=Asly ( d- ;)
(3.689)=226.19x443x 45--
2- =4324274.747Nmm =4.324kNm
(A.24)
(A.25)
(A.26)
(A.27)
186
A.3.2 By Swamy and AI-Taan
(a) Model calculation of slabs with fibre for specimen SOSC 21
fck = 47.24N / mm 2
df == 0.5mm
If == 25mm
p == 0.5%
Fibre spacing, S == 25( df J~ == 25 x ( 0.5 )~ = 5mm (A.28)plf 0.5 x 25
E f = 2.05 x 105 N / mm2
7r 2AI =="4 xO.5
rl == 0.25mm
Ec = 5000~ fck = 5000 x.J47.24 = 34365.68N / mm2 (A.29)
E == 2Gm(1 + ~) == 2Gm (1 + 0.15) == 2.3Gm (A.30)
EShear modulus of concrete, Gm == - = 14941.6
2.3
/3== 2nGm == 2x7rx14941.6 =0.892 (A.31)
E A In(~J 2.05 x 105
X 7r X 0.52
x In(_5_)I I r 4 0.25
I
Orientation factor, rJo == 0.41 for fibres in full concrete section and 0.64 for fibres in
tension zone alone
tanh(f!t) tanh( 0.89~x 25)
'11 ~ 1- (f31;) =1- (0.89~x 25) ~ 0.9103 (A.32)
Bond efficiency factor, rJb = 1
Ultimate strength in tension of composite,_ II
G'cu - rJOrJlrJb 2r - VIdl25 0.5
== 0.41x 0.9103x Ix 2x 2.3x-x- == 0.42920.5 100
(A.33)
187
(A.36)
(A.35)
(A.34)Force in fibres in tension zone, Fft = ucub(D - dn) = 0.4292 x 1000x (60 - dn)
Force in tension steel, Fs/ = Asfs = 226.08 x 443 = 100153.44N
Strain in extreme fibre of elastic uncracked tension zone,
6 = ~fcu =.J47""24 =0.00167o 4115 4115
Force in compression,
F = 0.77fc" ( _ &O)bdc &" n
6" 3
= 0.77X47.24(0.0035_ 0.00167)XI000Xd =30589.473d0.0035 3 n n
Equating C = T,
Fji +Fs/ =Fc
0.4292 x 1000 x (60 - d n ) + 100153.44 = 30589.473dn
Depth of neutral axis, dn = 4.059mmDistance from extreme compression fibre to the centre of composite block,
k,= (2-~J+2 d.=[(2_0~~oOo136;r+2]4'059=1.7372mm (A.37)
4(3- ::) 4(3- O~~o0013657)
(D-dJM=Fc(dn-k2 )+FAd-dJ+Fft 2 (A.38)
= 30589.473 x 4.059(4.059 -1.7372)+ 100153.44x (45 - 4.059)+ 24009.877 x (60 - 4.059)2
= 5060231.04Nmm =5.06kNm
(b) Model calculation of slabs without fibre for specimen SOSCll
fck =42.15N / mm2
b =1000mmD== 60mm
d == 45mm
h == 443N / mm2
As == 226.08mm 2
&u == 0.0035
& == ~fck = .J42i5 =0.0015777o 4115 4115
F:/ == Ash = 226.08x 443 = 100153.44
(A.39)
188
2+(2- 0.0015777)
_--:--__0._0_03_5_+_ X4.17355 =1.80094X(3- 0.0015777)
0.0035
F=0.67 jo.(&. -.6f}d,e
0.67X42.15X(0.0035-. 0.0015777)x 1000
= 3 =23997.163dn0.0035
d =F.t =100153.44 =4.17355mmn Fe 23997.163
2+(2- 80J2k 8"
2 = xdn =4X(3- 8
0 J81/
M" =(Fe X dJ(dn- k2)+ FS1 (d - dJ=(23997.163x 4.17355X4.17355 -1.8009)+ 100153.44(45 -4.17355)=4326538.279Nmm = 4.33kNm
A.3.3 By Lim and Paramasivam
(a) Model calculation of slabs with fibre for specimen SOSC21
lek =47.24N / mm2
M" =(J't"bh!!L+ As (J'sy (h+ht)2 2
Post cracking strength of concrete, (J't" = TlITloVflf!JL2r
Length efficiency factor, Tli =0.5
Orientation factor, Tlo =~ (Rajagopal et aI., 1974)7r
Vf = 0.5
If =25mm
Ultimate pullout bond strength of the fibre, T" =2.3N / mm2
r = 3.125 ratio of fibre cross sectional area to perimeter = m12
= 0.125mm4m1
for fibre reinforced concrete, a l =0.9
(J't" =0.5 x~ x 25 X0.5 x 2.3 =0.9321N / mm2
7r 2xO.125x25
(A.40)
(A.41)
(A.42)
(A.43)
(A.44)
(A.45)
(A.46)
189
Depth of tensile zone,
a a h- '_As_a_-IY 0.9x 0.9x 47.27 x 45 _ 226.08 x 443h, = _I_cu__-.::ho-- = ~1O~O~O:.._~ = 41.3747mm
alacu + a,u 0.9 x 0.9 x 47.24 + 0.9321
41.3747 443Mu = 0.9321x 1000x 45x +226.08x-x (45 +41.3747)
2 2=5193082.219Nmm = 5.19kNm
(b) Model calculation of slabs without fibres for specimen sosen
Ick =42.15N / mm2
if =25mm
For concrete without fibre, a l = 0.85
h=45mmAs =226.08mm2
a sy =443N / mm2
b=1000mma cu =O.8/ck = O.8x 42.15 =33.72N / mm2
alacu h - Asasy 0.85 x 33.72 x 45 _ 226.08 x 443
h = b = 1000 = 41.5057/ ala
clI0.85x33.72
aM =A-:2:.(h+h)
u s 2 I
=226.08x 443 x(45+41.5057)= 4331921.717Nmm = 4.33/cNm2
A.4 Computation of mid span deflection
A.4.1 Model computation for specimen soscn
(a) By ACI method
Deflection at first crack load of 13.08kN
hk =42.15N / mm2
b =1000mmd=45mmD=60mmEs = 2.05x lOs N / mm2
(A.47)
(A.48)
(A.49)
(A.50)
190
As/ =226.19mm2
I: =0.8/ek =0.8x 42.15 =33.72N / mm2
Ee =4700.J7: =4700x.J33.72 =27292.394N / mm2
m=Es = 205000 =7.511Ee 27292.394
bxxx~=mAs/(d - x)2
1000xxx~ =7.511x 226.19x(45 -x)2
~ x =10.6682mm
bD3
I gr =- =18000000mm4
12bx3
2I er =-3-+ mAs/(d-x)
1000x10.66823= 3 +7.328x 226.19x(45 -10.6682Y = 2358391.299mm
4
M = lerIgr = 3.6003x18000000 =21601 Oll.Ter % 30 8 lVmm
5X(13·08)X150045 )7/4 1.5
8=--=· =1.17005mm384 EIgr 384x 27292.394x 18000000
Deflection in the second stage, ie. after cracking for a load of 14.76kN
C4.76
)X15002
M = )7/2 = 1.5 =2767500Nmm8 8
I" =[(~JX1,}[I-(~ )']X1<,
[(2160180)3 ] [ (2160180)3]= 2767500 x 18000000 + 1- 2767500 x 2358391.299
= 9796942.403mm 4
5 (14.76) 48= 5)7/4 _ x -Ux1500
384Eleff
- 384 x 27292.394 x 9796942.403 = 2.4258mm
(A.51)
(A.52)
(A.53)
(A.54)
(A.55)
(A.56)
(A.57)
(A.58)
(A.59)
(A.60)
(A.61)
191
(b) By IS method
A.4.2 Model calculation for specimen SOSCll
Deflection at first crack load of 13.08kN
Jek =42.15N / mm 2
Ee = 5000~Jek = 32461.52N / mm2
Es =2.05xlOsN / mm2
m =Es =6.32Ee
M = Je,!gr = 0.7.JY::Igr = 0.7x.J42I5 x 18000000
er % % 30
=2726767.317Nmm
5 [4 5 x (13.081 )x 15004
o= P = 11.5 . = 0.983mm384EIgr 384x 32461.52 x 18000000
After cracking at a load of 14.76kN
bx2
- =mx As, x (d - x)2
1000xx2
2 =6.161x 226.19 x (45 - x)
~x=9.892mm
bx3
I er =3+ mAs,(d-x)2
1000x9.8923
= 3 + 6.32 x 226.19 x (45 - 9.892)2 = 2.08 xl06 mm4
'7 ~ ~(1- ~) ~ j: (1-~) =j(l-k)=(I- ~)I-k)x
k=-45 =0.2198
'7 =(1- ~)I-k)=(I- 0.2;98)(1_0.2198)= 0.723
wl2 (14.76/)x 15002
M = 8 = 11.~ = 2767500Nmm
(A.62)
(A.63)
(A.64)
(A.65)
(A.66)
(A.67)
(A.68)
(A.69)
(A.70)
(A.71)
192
leff = ler = 2.08 X106
== 4274938.34mm4
1.2 _(MerJ 1.2 _(2726767.317)x 0.723M ry 2767500
8 = 5p14 = 5X(14.7X.5)X 15004
= 4.67mm384Eleff 384 X32461.52 X4184034.496
A.5 Calculation of Crack width
By Gergely Lutz
A.5.1 Model calculation for specimen SOSCll
D=60mmd=4Smmfek =42.15N / mm2
de =lSmmb =1000mmI =1S00mmAs, =226.19mm2
n = No. of bars in tension zone = 8Es = 20S000N / mm2
Ee=5000~fck =5000x .J42.15 = 32461.S1N / mm2
m =Es =6.32Ee
Ae= 2(60-4S)xlOOO = 30000mm2
A_e =37S0mm2
nx
bxxx"2 =mAs/Cd -x)
xlOOOx xx - =6.32x 226.19 x (45 - x)
2~ x =9.8919mmkd =x =9.8919mm
For load = 13.08kN (first crack load)
For first crack load, I = I gr = 18000000mm4
(A.72)
(A.73)
(A.74)
(A.75)
(A.76)
193
p = 13.08 = 8.72kN1.5
M_ p12 = 8.72 X 1.5
2= 2.4525kNm
- 8 8
_ mM(d - x) = 6.32 x 2,4525 X 106
x (45 -9.8919) = 29,471fst - I 18000000
gr
-6 '~dAe (D-kd)f.Wer =l1xl0 X,te-; d-kd sf
(60 - 9.8919)-llxl0-6 xVI5x3750x .. x29,471=0.0177mm
- . 45-9.8919
(A.77)
(A.78)
(A.83)
(A.80)
(A.81)
(A.82)
(A.79)IifJ= ( )
e 1.2- ~ 1]
k =!... = 9.8919 =0.21982d 45
1] = (1- ~ )(1-k) =(1- 0.2~982)(1-0.21982) = 0.723
fer = 0.7~ fek =0.7x .J42.15 = 4.5446
M = Igrfer = 18000000 X 4.5446 = 2.726kNmer y 30
2.04xl064
Ieff = (2.7675) = 4377746.158mm1.2 - X 0.723
2.726
f.- mM(d-x) _ 6.1611x2.7675xl06 x(45-9.8919)
sf - I - 6 =136.772eff 4.37xl0
W er = llx 10-6X V15 X 3750 x(60 - 9.8919)x 13677 = 0 082mm
45-9.8919 . .
D 60y=-=-=30mm
2 2I er
194
APPENDIXB
STUDIES ON SIMPLY SUPPORTED TWO WAY SLABS
B.I Computation of Ductility Factor
B.I.I Model calculation for the specimen STSCll
Ductility factor = Deflection at ultimate load (ou) / Deflection at yield load (Oy)J1 =8ul8y (B.l)
Ultimate load, Pu =13T
Deflection at ultimate load, 8u =37.6mm
Yield load Pyis computed as given below:
f ck =42.l5N / mm2
D=60mmd=45mmf y = 443N / mm2
1C x 62 xlOOOA = 4 = 209.4mm2
st, 135
1C x62 xlOOOAst, = 4 =141.3mm2
2001s =1000mm
11 =1500mm
bD3
1=-gr 12
1000x603
= 12 = 18000000mm
Dy=-=30mm
2
Ec =5000~fck =32461.515N /mm 2
Em=_SEc
2.05xl0s= =6.3155000x~fck
(B.2)
(B.3)
(B.4)
195
bxxx~=mA.tf (d- x)2 .XlbXT = mA.tf. (d -Xs )
2
1000x Xs = 6.315x209.4x(45-xs )
2=> x,r :::: 9.666mm
Xlbx-L = mAst (d -X,)2 .
2
1000x~ = 6.315xI41.3x (45 -x,)2
=> x, ::: 8.113mm
b 3ler ::::.5..-+ mA_ (d-X,r)2'3 ~.
::: 1000x 9.6663
+ 6.315x 209.4x (45-9.666)2 =1951993.0163
M _ fy xler,s-
m(d-x,r)
::: 443 x 1951993.016 ::: 3875393.675Nmm6.315 x (45 -9.666)
bx 3ler. ::: _, + rnA (d - n)2
I 3 511
1000 X 8.1133
::: 3 +6.315xI41.3x(45-.8.113)2 =1392122.907
M_ fylcIj,-
m(d-x,)
::: 443x1392122.907 =2647491.7496.315x(45-8.113)
M =M,r+M,y 2
3875393.675 + 2647491.749= 2 = 3261442.712Nmm
Mp = y
y 008121 2• s
3261442.712::: 0.0812x10002 =40.I65Nlmm
(B.5)
(B.6)
(B.7)
(B.8)
(8.9)
(B.10)
(B.11)
196
Py = Py x 1x 1.5 = 60.247kN = 6.l41t
Ou =37.6mm
Oy = 10A1mm
Ductility factor =~ = 37.6 =3.612Oy 10.41
B.2 Computation of Collapse Load
B.2.1 Model calculation for the specimen STSC13
By yield line method
fck =45.l3N / mm2
f y =443N / mm2
;r X62 x1000Short span reinforcement, A I = 4 = 209.4mm2
s, 135
;r x62 x1000Long span reinforcement, A I = 4 = 141.3mm2
s/ 200
f y =443
b=1000mmFbe =1
d=45mm
Short span moment, M =f A d(l- Asl, f y
)us Y sl, bdl'
~ck
=443x209Ax45x(1- 209Ax443 )=3983713.245Nmm\. 1000x45x45.13
Long span moment, M I =f A d(l- ASI1 f y)
u Y si/ bdr~ck
443 14(
141.3X443)= x 1.3 x 45 x 1- . = 2729994. 168Nmm1000x 45x 45.13
M.u =---!!:!. =1.459M UI
(B.12)
(B.B)
(B.14)
197
Collapse load, (B.lS)
x =~1 + i1 +~1 + i3
Y =~1+i2 +~1+ i4
it and i3are ultimate negative moment of resistance per unit width in X direction
i2 and i4 ultimate negative moment of resistance per unit width in Y direction
For Simply Supported Slabs, i1 =i2 = i3 = i4 = 0
X=2, Y=26M
II,/-ly2
P - .
j - 1x (_1)2 (~'--1+~3p-X-1.-52-1Y1.5
=14.976MIIS
=59.659N I mm
Pj = 59.659x Ix 1.5 = 89.488kN =9.122t
B.3 Computation of Theoretical Deflection (Purushothaman, 1984)
B.3.1 Model calculation for the specimen STSCl3
fck =45.l3N / mm2
b=1000mmD=60mmd=45mm
f y =443N I mm2
AS1 =209.4mm2,
AS11 = 141.3mm2
Is =1000mm
I, =1500mm
bD3 1000x603
I gr =12= 12 =18000000mm4
Dy=-=30mm
2
f: =0.8x hk =36.104
Ec =4700-17: =28240.704N / mm 2
(B.l6)
(B.l7)
(B.l8)
(B.I9)
(B.20)
198
Es = 2.05x10sN / mm2
hr =0.62ft =3.725
Em=_S =7.259
Ee
First stage up to first crack
I grMer =hr-
y
Mer = 3.725x18000000 =2235000Nmm30
Mer =0.0812PeJI.2
= 2235000. =27.525N / mmPer 0.0812x 10002
Per =27.525 X 1X 1.5 =41.288kN =4.20914o = 0.00772Per ls
er Ee1gr
= 0.00772 x 27.525x 10004 =0.418mm
28240.704 x 18x 106
Second stage up to yield load (I =1eJ
xbx XX- =mAsl(d -x)
2x
bxxs x-..!.... =mAsl (d -xJ2 '2
1000x Xs =7.259x209.4x(45-xs)2
=> Xs == 10.275mm
Xbxx, x-.!... =mAsl (d -x,)
2 '2
1000x~ =7.259x141.3x(45-xs)2
=> XI =8.637
bXs3
A (d )21er, =-3-+ m sl, -Xs
(B.21)
(B.22)
(B.23)
(B.24)
(B.25)
(B.26)
(B.27)
199
=1000x 10.2753
+ 7.259x 209.4 X (45 -10.275/ =2194493.1873
.r xlM = Jy cr,
S m(d -xJ
= 443x 2194493.187 =3856727.125Nmm7.259 x (45 -10.275)
bx/ 2I Clj =-3-+ mAs1/(d-x,)
=1000 X 8.6373
+ 7.259x 141.3x (45 -8.637)2 =1571012.6643
M_ fy1cli,-
m(d-x,)
= 443x 1571012.664 =2636616.1627.259 x (45 - 8.637)
M = M", +M, =3246671.581Nmmy 2
My =0.0812Pi/
= My = 3246671.643 =39.984N/mmPy 0.0812/ 2 0.0812x 10002
S
1 +1/ = cr, crt =1882752.926mm4
cr 2
Py = Py X Ix 1.5 == 59.976kN = 6.114/
(py - Pcr)xl/ x 0.00772Oy = Ocr +-----'------
EJcr
=0.418 + (39.984 - 27.525) X 10004
X 0.00772 =2.227mm28240.704 X 1882752.926
Third stage at Johansen's load
From B,Z.1
P j =59.659N/mm
(Pj - p y )xO.00772xIs4
8. == 0 +---=--....:....-----J y 0.5/
crE
c
= .227+ (59.659-39.984)xO.00772xl0004
=7.94mm2 0.5 x 1882752.926x 28240.704
(B.28)
(B.29)
(B.30)
(B.31)
(B.32)
(B.33)
(B.34)
(B.35)
200
B.4 Prediction of crack width (Nawy, 1972.)
From equation 5.6
W =kf3fs'~M I
M =db1s2
I Qdb1 =6mm =O.236in
S2 =200mm =7.87inAQ=_s\At
\
1r 62-x. As = '12 x2.54 xlO)x 4 = O.0989m2
\ \ 135
Atl = 12(db1 +2C1)=12(O.236+2X ;:4)= 14.171m2
Q= 0.0989 = 6.98 x10-3
14.171
M = 0.236 x7.87 = 266.257I 6.98x10-3
is = OAx 443 = 177.2N / mm2 = 25694psi = 25.694ksi
wer =4A8x 10-5 x1.25x 25.69x.J266.65 = O.02347in = O.59634mm
(836)
(8.37)
(8.38)
201
APPENDIXC
STUDIES ON ONE WAY RESTRAINED SLABS
C.l Computation of Collapse Load
C.1.1 Model calculation for the specimen with fibre FOSC21
From 2.6.2
M 2 W)2A +MB + Me =-4-
when moment of resistance of support and midsection are the same
M =W)2u 16
replacing W u by Pi
P [2M =_J_
u 16Moment of resistance is calculated as below by ACI method
fck = 48.69N / mm2
As =226.19mm2
f: = 0.9 fck =0.9 x48.69 =43.821N / mm2
f y =443N / mm2
Fbe =1
Af =50
r d =2.3
2rd FbeAf6 s(jlbre) = =0.00115
Es
0.003 = 6 s(jlbre)
C e-c=> e = 1.383c
/3=0.85 V;-27.6)xo.05=0 7326.89 .
a = Asfy _ 226.19 x443 _f3f:b - 0.732x 43.82x 1000 - 3.1226
(C.1 )
(C.2)
(C.3)
(C.4)
(C.S)
(C.6)
(C.7)
202
ac=-=4.26
f3e=1.383c = 5.9
'M = A f (d _::'+(5 b(h-e{.h +~_a,U 5 y\ 2) I ~ \2 2 2)
1(i, =0.00772x- Pf Fbe =0.19
df
( 3 123, {60 5.9 3.123'\Mu =226.l9x44\.45-~ )+O.l9x1000x(60-5.9\2+2-2)=4680393Nmm =4.68kNm
Rence collapse load by Johansen's yield line theory is
16P j =MIl Xl =33.28kN / m2
1Pj = 33.28x1.5 =49.92kN
C.1.2 Model calculation for the specimen without fibre FOSCll
Ick = 46.07N / mm2
f: =0.8/ck = 36.856N / mm2
fJ= 0.7836 5 =0.00115
AJya=-=3,473
fif:b
Mu =AJy( d -~J= 4335098Nmm =4.33kNm
M x16Rence collapse load, Pj = u
12=30.79
Pj = 30.79 X1.5 = 46.24kN
C.2 Computation of Deflection
C.2.1 Model calculation for the specimen FOSCll
hk = 46.07N/mm2
I: = 0,8 xhk = 36,856N / mm2
(C.S)
(C.9)
(C.lO)
(C.ll)
(C.l2)
(C.l3)
(C.14)
203
fer =0.62.JJ: =3.763N Imm2
Ee = 4700fl = 28533.297N Imm2
Es = 2.05x 105 N I mm2
E.m =_s = 7.184Ee
Ast =226.19mm2
b=1000mmI gr = 18000000mm4
Xb X xx- =mAsted -X)
2
x2
1000x- =7.184x 226.19x (45 -X)2
=> x= 10.577bx3
2I er =-3-+ mAs,(d-x)
= 1000x10.5773
+7.184x226.19x(45-10.577)2 = 2319898.437mm4
3
Deflection up to first crack
1.5 x 9.81 81NI 8 k IPer = = 9. mm = 9. 1 N m1.5 x 1
8 =_1_ Pe,z4er 384 EJgr
=_l_ x 9.81x15004
=0.2518mm384 28533.297 x18000000
In the second stage up to Johansen's load (Pj )
8 = 8 + 1 (P j - Pe'y4J er 384 E I
e er
Pj 4.71x9.81Pj = 1.5 x 1 = 1.5 = 30.82kN1m = 30.82N Imm
8. =0.2518+-1-x (30.82-9.81)x15004
=4.436mmJ 384 28533.297 x 2319898.437
(C.15)
(C.16)
(C.17)
(C.18)
(C.19)
(C.20)
(C.21)
204
APPENDIXD
STUDIES ON TWO WAY RESTRAINED SLABS
D.1 Computation of Deflection of Two Way Restrained Slab Based on the ModelProposed By Muthu et al. (1979)
D.1.1 Model calculation for the specimen FTSCll
fck =45.34N / mm2
f: =0.8 x fck =36.272N / mm 2
fcr = 0.62flj = 3.734N / mm2
Ec=4700flj =28306.333N / mm2
E, =2.05 x105N / mm2
Em=-S =7.242
Ec
Area of steel along short span, Asts = 208.2mm2
Area of steel along long span, AStl = 150.129mm2
b=1000mmLong span, II =1500mm
Short span, Is =1000mm
I gr =18000000mm4
d=45mmf y =443N / mm 2
First stage (deflection up to first crack)
M = fc'! gr =3.734 x18000000 =2240400NmmIT y 30
M cr =0.0368pjs2
= 2240400 =60 8 /Pcr 0.0368xl000 2 • 8N mm
Pcr =60.88 x 1x 1.5 =91.32kN =9.309t
6 =0.0022Pcrls4
cr E Ic gr
6 =0.0022 x 60.88 xl 0004_
cr 28306.333 x 18 xl 06 - 0.263mm
(D.1)
(D.2)
(0.3)
(D.4)
(D.S)
(D.6)
(D.?)
205
Second stage (deflection up to collapse load)x
bxxx- =mAsted -x)2x
bxxs xt =mAst, (d -xs )
2x1000x _s_ = 7.242 x 208.2 x (45 - xs )
2=> Xs =10.238mm
bxxix~=mAst (d -XI)2 .,2
1000x~ = 7.242x150.129x(45-xs)2
=> XI =8.864mm3
Icr, =bx3, + mAst, (d - X.,)2
= 1000x 10.2383
+ 7.242x 208.2x (45 -10.238)2 = 2179705.8763
3bXI 2
1cr, =-3- + mAstl (d - XI)
= 1000x8.8643
+7.242x150.l29x(45-8.864)2 =1651871.4793
I cr + I aI =' Icr 2
= 2179705.876+ 1651871.479 = 1915788.678mm4
2
Determination of collapse load
Short span moment, Mus is given by M =fA d(l- As"fyJ
liS y s/, bdlf.ck
(208.2 x 443 )=443x208.2x45x 1- = 3962843.434Nmm
1000x 45x 45.34Long span moment, Mul is given by
Mill = fyAs'1d(l- As"fy)
bdfck
(150.129X443)=443x150.129x45x 1- = 2895265.36Nmm
1000 x 45 x 45.34
: (D.8)
(D.9)
(D. 10)
(D.ll)
(D. 12)
(D.13)
206
From equation 2.37
M,u=.----!!!...= 1.369
Mill
(D.14)
(D.15)
(0.16)
(0.17)
X =~I+il +~I+i3
Y = ~1+i2 +~1+i.
il =i2 =i3 =i4 =1
X =Y=2.J2
p. = 6M"",uy2 . = 6xM.. x1.367x(2.J2L =30.545M.. =121.045Nlmm
) lx(_l)2W1+3,uX1.52-If IX(_1)2~I+3X1.367X1.52-If15 15
Pj =121.045 x1x 1.5 = 181.568kN = 18.51t
As,Px = bd'
S
208.2=100 x100 = 0.463%Ox45
As,P - I
Y - bdI
150.129=1000x39 xl00 =0.385%
( J0.3855 ( J ( )2X=(P, +pJ'"''x~ x ~: x L;,
=(0.463+0.385)-0.1932 X ( 443 )0.3855 X (1000)X(1000)2 =501.66536.272 1500 60
a =6.744 x10-5X + 0.1094= 6.744x 10-5x501.665 + 0.1094 = 0.143
o. = ~ (Pj - PcJx O.0022xl/J Ucr +----"-------
a/crEe
= 0.263 + (121.045 - 60.88)x 0.0022 X10004_ 1 3
O.I43 x 1915788.678x 28306.333 - 7. 3mm
(D.18)
(D.19)
(D.20)
(D.21)
(0.22)
207