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+b=0.3//column width in m
+c1=0.4//column depth in m
+fck=20//in MPa
+sigma_cbc=7//in MPa
+sigma_st=275//in MPa
+P1=1200//load on column, in kN
+P2=0.05*P1//weight of footing, in kN
+P=P1+P2//in kN
+q=200//bearing capacity of soil, in kN/sq m
+A=P/q//in sq m
+L1=2//in m
+L2=A/L1//assuming footing to be square
+L2=3.2//assume, in m
+p=P1/L1/L2//soil pressure, in kN/sq m
+bc=b/c1
+ks=0.5+bc//>1
+ks=1
+Tc=0.16*sqrt(fck)*10^3//in kN/sq m
+Tv=Tc
+//let d be the depth of footing in metres
+//case I, refer Fig. 11.15 of textbook
+//short direction
+d1=L1*(L2-c1)/2*p/(Tc*L1+L1*p)//in m
+//long direction
+d2=L2*(L1-b)/2*p/(Tc*L2+L2*p)//in m
+//case II: refer Fig. 11.16 of textbook; we get a quadratic equation of the form e d^2 + f d + g = 0
+e=p+4*Tc
+f=b*p+c1*p+2*(b+c1)*Tc
+g=-(L1*L2-b*c1)*p
+d3=(-f+sqrt(f^2-4*e*g))/2/e//in m
+d3=0.47//assume, in m
+d=max(d1,d2,d3)//in m
+//bending moment consideration, refer Fig. 11.17 of textbook
+Mx=1*((L1-b)/2)^2/2*p//in kN-m
+My=1*((L2-c1)/2)^2/2*p//in kN-m
+d4=sqrt(My*10^6/0.8/10^3)//in mm
+d4=480//>470 mm (provided for shear)
+d=d4//in mm
+z=0.92*d//lever arm, in mm
+//short direction
+Ast1=(Mx*10^6/sigma_st/z)//in sq mm
+Ast=L2*Ast1//steel required for full width of 3.2 m, in sq mm
+b1=L1//central band width, in m
+beta=L2/L1
+Astc=L1/(beta+1)*Ast//in sq mm
+//provide 12 mm dia bars
+dia=12//in mm
+n1=Astc/0.785/dia^2//no. of 12 mm dia bars
+n1=13//assume
+Astr=Ast-Astc//steel in remaining width, in sq mm
+n2=Astr/0.785/dia^2
+n2=4//assume
+n2=n2/2//on each side
+Tbd=1.12//in MPa
+Ld=dia*sigma_st/4/Tbd//in mm
+c=50//side cover, in mm
+La=(L1-b)/2*10^3-c//>Ld, hence OK
+//long direction
+Ast1=(My*10^6/sigma_st/z)//in sq mm
+Ast=L1*Ast1//steel required for full width of 2 m, in sq mm
+//provide 18 mm dia bars
+dia=18//in mm
+n=Ast/0.785/dia^2//no. of 18 mm dia bars
+n=12//assume
+Ld=dia*sigma_st/4/Tbd//in mm
+c=50//side cover, in mm
+La=(L2-c1)/2*10^3-c//>Ld, hence OK
+D=d+dia/2+100//in mm
+D=590//assume, in mm
+mprintf("Summary of design:\nOverall depth of footing=%d mm\nCover=100 mm bottom; 50 mm side\nSteel-long direction\n%d bars of 18 mm dia in %d m width equally spaced\nShort direction\nCentral band %d m:%d-12 mm dia bars equally spaced\nRemaining sides:%d-12 mm dia bars on each side",D,n,L1,L1,n1,n2)