Question

What is the drawback of maximum principal stress theory?

A body is under action of two principal stresses of 40 N/mm² and –70N/mm², and the third principle stress being zero. If the elastic limit in simple tension as well as compression is 200 N/mm², find the factor of safety based on the elastic limit according to -          

1. Maximum shear stress theory;
2. Maximum strain energy theory;
3. Maximum shear strain energy theory.

Take m = 0.3.