Question

Single-span beams collapse as ________

(a) single-bar mechanism

(b) two-bar mechanism

(c) three-bar mechanism

(d) does not collapse

I have been asked this question in unit test.

Asked question is from Plastic-Collapse Load topic in section Plastic and Local Buckling Behaviour of Steel of Design of Steel Structures

Answer 1

The correct choice is (b) two-bar mechanism

To elaborate: Single-span beams generally collapse as two-bar mechanisms with a hinge at each support and plastic hinge within the span.