Question

When a member is subjected to uniaxial tensile or compressive stress in presence of shear stress  τ , yield occurs when ___

(a) fy^2 = f^2 – 3 τ

(b) fy^2 = f^2 + 3 τ^2

(c) fy^2 = f^2 – 3 τ^2

(d) fy^2 = f^2 + 3 τ

The question was asked by my school teacher while I was bunking the class.

This interesting question is from Plastic Design of Portal Frames, Effect of Axial and Shear force on Plastic Moment Capacity in portion Plastic and Local Buckling Behaviour of Steel of Design of Steel Structures

Answer 1

The correct choice is (b) fy^2 = f^2 + 3 τ^2

The best explanation: When a member is subjected to uniaxial tensile or compressive stress in presence of shear stress  τ, yield occurs when fy^2 = f^2 + 3 τ^2.