Moment Distribution Method MCQ with answer and solution

Concept

The Moment Distribution Method, developed by Hardy Cross, is an iterative stiffness method used to analyze indeterminate structures like continuous beams and rigid frames.

Formula

Carry-Over Factor = M_remote / M_near, Stiffness K = (4EI/L) for fixed far end

Explanation

The moment distribution method is a displacement method of structural analysis suitable for continuous beams and frames. It can handle members with variable cross-sections by appropriately modifying the stiffness, carry-over factors, and distribution factors. Option A is incorrect because it uses successive approximation rather than solving simultaneous equations directly; option B yields results to any desired degree of approximation, not exact in a finite number of steps; option D is incorrect because the carry-over factor for a prismatic member is 0.5, not 1.

Why the other options are wrong

A: It avoids direct solution of simultaneous equations through successive approximations. B: It yields approximate results that converge to the exact solution with more iterations. D: The carry-over factor for a standard prismatic beam is 0.5, not 1.

Shortcut

Remember that Hardy Cross moment distribution is an iterative approach using distribution factors and carry-over factors (typically 0.5 for prismatic members).

Common mistake

Confusing the carry-over factor of 0.5 for prismatic members with unity, or thinking the method directly solves simultaneous equations like slope-deflection.