diff options
Diffstat (limited to '3683/CH7/EX7.2/Ex7_2.sce')
-rw-r--r-- | 3683/CH7/EX7.2/Ex7_2.sce | 58 |
1 files changed, 58 insertions, 0 deletions
diff --git a/3683/CH7/EX7.2/Ex7_2.sce b/3683/CH7/EX7.2/Ex7_2.sce new file mode 100644 index 000000000..570bb956a --- /dev/null +++ b/3683/CH7/EX7.2/Ex7_2.sce @@ -0,0 +1,58 @@ +sigma_cbc=5//in MPa
+sigma_st=230//in MPa
+MF=1.4//modification factor
+//let a be span to depth ratio
+l=4.5//span, in m
+a=MF*20
+D=l*1000/a//in mm
+D=160//approximately, in mm
+//to calculate loading
+self_weight=25*(D/10^3)//in kN/m
+finish=1//in kN/m
+partitions=1//in kN/m
+live_load=4//in kN/m
+W=self_weight+finish+partitions+live_load//total load, in kN/m
+lef=l+D/1000//in m
+M=W*lef^2/8//in kN-m
+//check for depth
+d=(M*10^6/(0.9*sigma_cbc/2*0.29*1000))^0.5//in mm
+//assume 12 mm dia bars
+D=d+12/2+15//in mm
+//the calculated value of D is more than its assumed value
+D=1.1*D//revised value of depth, in mm
+D=250//assume, in mm
+self_weight=25*(D/10^3)//in kN/m
+finish=1//in kN/m
+partitions=1//in kN/m
+live_load=4//in kN/m
+W=self_weight+finish+partitions+live_load//total load, in kN/m
+lef=l+D/1000//in m
+M=W*lef^2/8//in kN-m
+//check for depth
+d=round((M*10^6/(0.9*sigma_cbc/2*0.29*1000))^0.5)//in mm
+D=d+12/2+15//in mm
+D=250//approximately, in mm
+Ast=round(M*10^6/(sigma_st*0.9*d))//in sq mm
+s1=1000*0.785*12^2/Ast//which is less than 3d= 690 mm
+s1=155//approximately, in mm
+pt=Ast/1000/d*100//in %
+Ads=0.12/100*1000*D//distribution steel, in sq mm
+//assume 8 mm dia bars
+s2=1000*0.785*8^2/Ads//which is less than 5d= 1150 mm
+s2=165//approximately, in mm
+//to calculate development length
+w=0.23//support width, in m
+l=l+w//in m
+R=W*l/2//reaction at support, in kN
+M1=R*w/2-W*w^2/2//bending moment at the face of wall, in kN-m
+sigma_st=M1*10^6/(Ast/2*0.9*d)//in MPa
+Tbd=0.6//in MPa
+Ld=12*sigma_st/(4*Tbd)//in mm
+La=w*1000-25//available length for bar over wall, which is greater than development length
+//check for shear
+V=W*lef/2//in kN
+Tv=V*10^3/(1000*d)//in MPa
+Tc=0.2212//permissible shear in concrete for p=0.315 and M15, in MPa
+Tc=1.15*Tc//permissible shear for slabs, in MPa
+//Tc>Tv; hence no shear reinforcement is required
+mprintf("Summary of design\nSlab thickness=%d mm\nCover=15 mm\nMain steel = 12 dia @ %d mm c/c\nAlternate bars are bent up at 45-degree at support at a distance of l/7 from support face\nDistribution steel=8 dia @ %d mm c/c",D,s1,s2)
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