clear // //The given composite section may be divided into simple rectangles and triangle //variable declaration A1=100.0*30.0 //Area of 1,mm^2 A2=100.0*25.0 //Area of 2,mm^2 A3=200.0*20.0 //Area of 3,mm^2 A4=87.5*20.0/2.0 //Area of 4,mm^2 A5=87.5*20.0/2.0 //Area of 5,mm^2 A=A1+A2+A3+A4+A5 //Total area,mm^2 //Due to symmetry, centroid lies on the axis y-y. A reference axis (1)–(1) is choosen as shown in the figure. The distance of the centroidal axis from (1)–(1) X1=100.0 X2=100.0 X3=100.0 X4=2.0*87.5/3.0 X5=200-X4 xc=(A1*X1+A2*X2+A3*X3+A4*X4+A5*X5)/A Y1=135.0 Y2=70.0 Y3=10.0 Y4=(20.0/3.0)+20.0 Y5=Y4 yc=(A1*Y1+A2*Y2+A3*Y3+A4*Y4+A5*Y5)/A //With reference to the centroidal axis x-x and y-y, the centroid of the rectangle A1 is g1 (0.0,135.0-yc), that of A2 is g2(0.0,70.00-yc), that of A3 is g3 (0.0, yc-10.0), the centroid of triangle A4 is g4 (41.66,yc-20.0-(20.0/3.0) ) and that of A5 is g5 (41.66,yc-20.0-(20.0/3.0)). Ixx=(100.0*(30**3)/12.0)+(A1*((135.0-yc)**2))+(25.0*(100**3.0)/12.0)+(A2*((70.0-yc)**2))+(200*(20**3)/12.0)+(A3*((yc-10.0)**2))+((87.5*(20**3)/36.0)+(A4*((yc-20.0-(20.0/3.0))**2)))*2 printf("\n Ixx= %0.1f mm^4",Ixx) Iyy=(30.0*(100**3)/12.0)+(100.0*(25**3.0)/12.0)+(20*(200**3)/12.0)+((20.0*(87.5**3)/36.0)+(A4*((41.66)**2)))*2 printf("\n Iyy= %0.1f mm^4",Iyy)