a=50;//cross section dimension,given,in mm
b=100;//cross section dimension,given,in mm
ta=1;//thickness,given,in mm
tb=2;//thickness,given,in mm
Ez1=50000;//Young’s modulus for the flange,given,in N/mm^2
Ez2=15000;//Young’s modulus for the web,given,in N/mm^2
Mx=1*10^6;