S1=50;//longitudnal direct stress,given,in N/mm^2
S2=25;//transverse direct stress,given,in N/mm^2
S3=40;//shear stress,given,in N/mm^2
El=120000;//given,in N/mm^2
Et=80000;//given,in N/mm^2
Glt=5000;//given,in N/mm^2
vlt=0.3;//given