Question

Loss of web capacity is given by ___

(a) Zpw / (fy – fw)

(b) Zpw (fy – fw)

(c) Zpw (fy + fw)

(d) Zpw /(fy + fw)

The question was asked during an interview for a job.

Asked question is from Plastic Design of Portal Frames, Effect of Axial and Shear force on Plastic Moment Capacity topic in chapter Plastic and Local Buckling Behaviour of Steel of Design of Steel Structures

Answer 1

Right answer is (b) Zpw (fy – fw)

To explain: Loss of web capacity is given by Zpw (fy – fw)  = Zpw fy { 1-√[1-(τw/τy)2] }.