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-rw-r--r--3683/CH1/EX1.1/Ex1_1.sce14
-rw-r--r--3683/CH1/EX1.10/Ex1_10.sce19
-rw-r--r--3683/CH1/EX1.11/Ex1_11.sce19
-rw-r--r--3683/CH1/EX1.12/Ex1_12.sce12
-rw-r--r--3683/CH1/EX1.13/Ex1_13.sce14
-rw-r--r--3683/CH1/EX1.2/Ex1_2.sce12
-rw-r--r--3683/CH1/EX1.3/Ex1_3.sce12
-rw-r--r--3683/CH1/EX1.4/Ex1_4.sce10
-rw-r--r--3683/CH1/EX1.5/Ex1_5.sce18
-rw-r--r--3683/CH1/EX1.6/Ex1_6.sce16
-rw-r--r--3683/CH1/EX1.7/Ex1_7.sce24
-rw-r--r--3683/CH1/EX1.8/Ex1_8.sce22
-rw-r--r--3683/CH1/EX1.9/Ex1_9.sce22
13 files changed, 214 insertions, 0 deletions
diff --git a/3683/CH1/EX1.1/Ex1_1.sce b/3683/CH1/EX1.1/Ex1_1.sce
new file mode 100644
index 000000000..45338b80f
--- /dev/null
+++ b/3683/CH1/EX1.1/Ex1_1.sce
@@ -0,0 +1,14 @@
+//let the depth of neutral axis be x
+b=200//width, in mm
+d=350//effective depth, in mm
+m=18.66 //modular ratio
+sigma_cbc=5//in MPa
+sigma_st=140//in MPa
+x=d/(1+sigma_st/(m*sigma_cbc))//in mm
+mprintf("The depth of neutral axis = %f mm\n", x)
+//to find area of steel
+Ast=b*x*sigma_cbc/(2*sigma_st)//in sq mm
+mprintf("Area of steel = %f mm^2\n", Ast)
+//to find percentage steel
+pst=Ast*100/(b*d)//in %
+mprintf("Percentage of steel = %f percent\n", pst)
diff --git a/3683/CH1/EX1.10/Ex1_10.sce b/3683/CH1/EX1.10/Ex1_10.sce
new file mode 100644
index 000000000..3c51a0e1d
--- /dev/null
+++ b/3683/CH1/EX1.10/Ex1_10.sce
@@ -0,0 +1,19 @@
+b=300//width, in mm
+D=700//overall depth, in mm
+Ast=4*.785*25^2//four 25mm dia bars, in sq mm
+cover=30//in mm
+d=D-cover//effective depth, in mm
+M=130*10^6//bending moment, in N-mm
+m=18.66//modular ratio
+//to find actual depth of neutral axis using b(x^2)/2=mAst(d-x), which becomes of the form px^2+qx+r=0
+p=b/2
+q=m*Ast
+r=-m*Ast*d
+x=(-q+sqrt(q^2-4*p*r))/(2*p)//in mm
+z=d-x/3//lever arm, in mm
+//assuming under-reinforced section, Mr=Ast*sigma_st(d-x/3) and equating Mr to M
+sigma_st=M/(Ast*z)//in MPa
+sigma_st=116//round-off, in MPa
+sigma_cbc=(sigma_st/m)*x/(d-x)//in MPa
+sigma_cbc=5//round-off, in MPa
+mprintf("Stress in steel=%d N/mm^2\nStress in concrete=%d N/mm^2",sigma_st,sigma_cbc)
diff --git a/3683/CH1/EX1.11/Ex1_11.sce b/3683/CH1/EX1.11/Ex1_11.sce
new file mode 100644
index 000000000..450118582
--- /dev/null
+++ b/3683/CH1/EX1.11/Ex1_11.sce
@@ -0,0 +1,19 @@
+b=350//width, in mm
+D=650//overall depth, in mm
+Ast=4*.785*22^2//four 22mm dia bars, in sq mm
+cover=25//in mm
+d=D-cover//effective depth, in mm
+W=20//UDL, in kN/m
+l=7//span, in m
+M=W*l^2/8*10^6//bending moment, in N-mm
+m=13.33//modular ratio
+//to find actual depth of neutral axis using b(x^2)/2=mAst(d-x), which becomes of the form px^2+qx+r=0
+p=b/2
+q=m*Ast
+r=-m*Ast*d
+x=(-q+sqrt(q^2-4*p*r))/(2*p)//in mm
+z=d-x/3//lever arm, in mm
+//assuming under-reinforced section, Mr=Ast*sigma_st(d-x/3) and equating Mr to M
+sigma_st=M/(Ast*z)//in MPa
+sigma_cbc=(sigma_st/m)*x/(d-x)//in MPa
+mprintf("Stress in steel=%f N/mm^2\nStress in concrete=%f N/mm^2",sigma_st,sigma_cbc)
diff --git a/3683/CH1/EX1.12/Ex1_12.sce b/3683/CH1/EX1.12/Ex1_12.sce
new file mode 100644
index 000000000..bf05bff0d
--- /dev/null
+++ b/3683/CH1/EX1.12/Ex1_12.sce
@@ -0,0 +1,12 @@
+b=250//width, in mm
+sigma_cbc=5//in MPa
+sigma_st=190//in MPa
+m=280/(3*sigma_cbc)//modular ratio
+M=75*10^6//bending moment, in N-mm
+//critical depth of neutral axis, Xc=d/(1+sigma_st/(m*sigma_cbc))=a*d
+a=1/(1+sigma_st/(m*sigma_cbc))
+d=(M/(b*sigma_cbc*a*(1-a/3)/2))^0.5//in mm
+d=640//round-off, in mm
+Xc=a*d//in mm
+Ast=b*Xc*sigma_cbc/(2*sigma_st)//in sq mm
+mprintf("Effective depth=%d mm\nArea of steel=%f mm^2",round(d),Ast)
diff --git a/3683/CH1/EX1.13/Ex1_13.sce b/3683/CH1/EX1.13/Ex1_13.sce
new file mode 100644
index 000000000..b5de4b312
--- /dev/null
+++ b/3683/CH1/EX1.13/Ex1_13.sce
@@ -0,0 +1,14 @@
+//b=d/2 (given)
+sigma_cbc=5//in MPa
+sigma_st=140//in MPa
+m=18.66//modular ratio
+M=65*10^6//bending moment, in N-mm
+//critical depth of neutral axis, Xc=d/(1+sigma_st/(m*sigma_cbc))=a*d
+a=1/(1+sigma_st/(m*sigma_cbc))
+d=(M/(sigma_cbc*a*(1-a/3)/4))^(1/3)//in mm
+d=530//round-off, in mm
+Xc=a*d//in mm
+b=d/2//in mm
+Ast=M/sigma_st/0.87/d//in sq mm
+Ast=1007//round-off, in sq mm
+mprintf("Dimensions of section=%d x %d mm\nArea of steel=%d mm^2",b,d,Ast)
diff --git a/3683/CH1/EX1.2/Ex1_2.sce b/3683/CH1/EX1.2/Ex1_2.sce
new file mode 100644
index 000000000..483b1dd7c
--- /dev/null
+++ b/3683/CH1/EX1.2/Ex1_2.sce
@@ -0,0 +1,12 @@
+//let the depth of neutral axis be x
+b=150//width, in mm
+d=400//effective depth, in mm
+Ast=804//area of steel, in sq mm
+m=18.66//modular ratio
+//b(x^2)/2=mAst(d-x)-->this becomes a quadratic equation of form px^2+qx+r=0
+p=b/2
+q=m*Ast
+r=-m*Ast*d
+//solving the quadratic equation
+x=(-q+sqrt(q^2-4*p*r))/(2*p)//in mm
+mprintf("The depth of neutral axis = %f mm", x)
diff --git a/3683/CH1/EX1.3/Ex1_3.sce b/3683/CH1/EX1.3/Ex1_3.sce
new file mode 100644
index 000000000..533537c99
--- /dev/null
+++ b/3683/CH1/EX1.3/Ex1_3.sce
@@ -0,0 +1,12 @@
+//assume d = 400 mm and b = 200 mm
+b=200//in mm
+d=400//in mm
+sigma_cbc=5//in MPa
+sigma_st=140//in MPa
+m=18.66//modular ratio
+Xc=d/(1+sigma_st/m/sigma_cbc)//in mm
+z=d-Xc/3//in mm
+Mr=b*Xc*sigma_cbc/2*z//in N-mm
+Ast=b*Xc*sigma_cbc/2/sigma_st//in sq mm
+pt=Ast*100/b/d//in %
+mprintf("When d is assumed as 400 mm and b as 200 mm\n(a) Position of neutral axis=%f mm\n(b) Lever arm=%f mm\n(c) Moment of resistance=%f kN-m\n(d) Percentage of steel=%f percent",Xc,z,Mr/10^6,pt)
diff --git a/3683/CH1/EX1.4/Ex1_4.sce b/3683/CH1/EX1.4/Ex1_4.sce
new file mode 100644
index 000000000..0866ccd58
--- /dev/null
+++ b/3683/CH1/EX1.4/Ex1_4.sce
@@ -0,0 +1,10 @@
+b=250//width, in mm
+d=500//effective depth, in mm
+sigma_cbc=5//in MPa
+sigma_st=140//in MPa
+m=18.66//modular ratio
+//to find critical depth of neutral axis
+Xc=d/(1+sigma_st/(m*sigma_cbc))//in mm
+z=d-Xc/3//lever arm, in mm
+Mr=b*Xc*sigma_cbc*z/2//in N-mm
+mprintf("Moment of resistance of the beam = %f kN-m",Mr/10^6)
diff --git a/3683/CH1/EX1.5/Ex1_5.sce b/3683/CH1/EX1.5/Ex1_5.sce
new file mode 100644
index 000000000..6539b9de7
--- /dev/null
+++ b/3683/CH1/EX1.5/Ex1_5.sce
@@ -0,0 +1,18 @@
+b=250//width, in mm
+D=550//overall depth, in mm
+Ast=1521//area of steel, in sq mm
+cover=25//in mm
+d=D-cover//effective depth, in mm
+sigma_cbc=7//in MPa
+sigma_st=140//in MPa
+m=13.33//modular ratio
+//to find critical depth of neutral axis
+Xc=d/(1+sigma_st/(m*sigma_cbc))//in mm
+//to find actual depth of neutral axis using b(x^2)/2=mAst(d-x)--> this will become of the form px^2+qx+r=0
+p=b/2
+q=m*Ast
+r=-m*Ast*d
+x=(-q+sqrt(q^2-4*p*r))/(2*p)//in mm
+//x>Xc; hence beam is over-reinforced
+Mr=b*x*sigma_cbc/2*(d-x/3)//in N-mm
+mprintf("Moment of resistance of the beam=%f kN-m",Mr/10^6)
diff --git a/3683/CH1/EX1.6/Ex1_6.sce b/3683/CH1/EX1.6/Ex1_6.sce
new file mode 100644
index 000000000..9729b27b1
--- /dev/null
+++ b/3683/CH1/EX1.6/Ex1_6.sce
@@ -0,0 +1,16 @@
+b=200//width, in mm
+d=450//effective depth, in mm
+Ast=3*.785*16^2//three 16 dia bars, in sq mm
+sigma_cbc=5//in MPa
+sigma_st=140//in MPa
+m=18.66//modular ratio
+//to find critical depth of neutral axis
+Xc=d/(1+sigma_st/(m*sigma_cbc))//in mm
+//to find actual depth of neutral axis using b(x^2)/2=mAst(d-x), which becomes of form px^2+qx+r=0
+p=b/2
+q=m*Ast
+r=-m*Ast*d
+x=(-q+sqrt(q^2-4*p*r))/(2*p)//in mm
+//as x<Xc, beam is under-reinforced
+Mr=Ast*sigma_st*(d-x/3)//in N-mm
+mprintf("Moment of resistance of the beam = %f kN-m", Mr/10^6)
diff --git a/3683/CH1/EX1.7/Ex1_7.sce b/3683/CH1/EX1.7/Ex1_7.sce
new file mode 100644
index 000000000..3e9345b47
--- /dev/null
+++ b/3683/CH1/EX1.7/Ex1_7.sce
@@ -0,0 +1,24 @@
+b=300//width, in mm
+D=700//overall depth, in mm
+Ast=3*.785*20^2//3-20mm dia bars, in sq mm
+cover=50//in mm
+d=D-cover//effective depth, in mm
+sigma_cbc=7//in MPa
+sigma_st=190//in MPa
+m=13.33//modular ratio
+l=6//span, in m
+w=25//unit weight of concrete, in kN/m^3
+//to find critical depth of neutral axis
+Xc=d/(1+sigma_st/(m*sigma_cbc))//in mm
+//to find actual depth of neutral axis using b(x^2)/2=mAst(d-x), which becomes of the form px^2+qx+r=0
+p=b/2
+q=m*Ast
+r=-m*Ast*d
+//solving quadratic equation
+x=(-q+sqrt(q^2-4*p*r))/(2*p)//in mm
+//x<Xc, hence beam is under-reinforced
+Mr=sigma_st*Ast*(d-x/3)//in N-mm
+UDL=(Mr/10^6)*8/l^2//in kN/m
+self_weight=w*b*D/10^6//in kN/m
+net_weight=UDL-self_weight//in kN/m
+mprintf("Moment of resistance=%f kN-m\nSafe uniformly distributed load that the beam can carry=%f kN/m",Mr/10^6,net_weight)
diff --git a/3683/CH1/EX1.8/Ex1_8.sce b/3683/CH1/EX1.8/Ex1_8.sce
new file mode 100644
index 000000000..4d58db746
--- /dev/null
+++ b/3683/CH1/EX1.8/Ex1_8.sce
@@ -0,0 +1,22 @@
+b=250//width, in mm
+D=500//overall depth, in mm
+Ast=4*.785*22^2//four 22 mm dia bars, in sq mm
+cover=25//in mm
+d=D-cover//effective depth, in mm
+l=5//effective span, in m
+sigma_cbc=5//in MPa
+sigma_st=190//in MPa
+m=18.66//modular ratio
+//to find critical depth of neutral axis
+Xc=d/(1+sigma_st/(m*sigma_cbc))//in mm
+//to find actual depth of neutral axis using b(x^2)/2=mAst(d-x), which becomes of the form px^2+qx+r=0
+p=b/2
+q=m*Ast
+r=-m*Ast*d
+x=(-q+sqrt(q^2-4*p*r))/(2*p)//in mm
+//as x>Xc, beam is over-reinforced
+Mr=b*sigma_cbc*x/2*(d-x/3)//in N-mm
+self_weight=25*(b/10^3)*(D/10^3)//in kN/m
+M=Mr/10^6-self_weight*l^2/8//moment of resistance available for external load, in kN-m
+W=4*M/l//in kN
+mprintf("The concentrated load the beam can support at centre=%f kN",W)
diff --git a/3683/CH1/EX1.9/Ex1_9.sce b/3683/CH1/EX1.9/Ex1_9.sce
new file mode 100644
index 000000000..40a69ff7d
--- /dev/null
+++ b/3683/CH1/EX1.9/Ex1_9.sce
@@ -0,0 +1,22 @@
+d=120//effective depth of slab, in mm
+//consider 1 m strip of slab
+b=1000//in mm
+s=80//spacing of 12mm dia bars centre-to-centre, in mm
+Ast=1000*.785*12^2/s//in sq mm
+l=3.2//span, in m
+sigma_cbc=7//in MPa
+sigma_st=140//in MPa
+m=13.33//modular ratio
+//to find critical depth of neutral axis
+Xc=d/(1+sigma_st/(m*sigma_cbc))//in mm
+//to find actual depth of neutral axis using b(x^2)/2=mAst(d-x), which becomes of the form px^2+qx+r=0
+p=b/2
+q=m*Ast
+r=-m*Ast*d
+x=(-q+sqrt(q^2-4*p*r))/(2*p)//in mm
+//as x>Xc, the beam is over-reinforced
+Mr=b*sigma_cbc*x/2*(d-x/3)/10^6//in kN-m
+UDL=Mr*8/l^2//in kN/m
+self_weight=25*(d/10^3)*(b/10^3)//in kN/m
+W=UDL-self_weight//in kN/m
+mprintf("The safe load for slab=%f kN/m",W)