Iterative method balancing joint moments in continuous beams.
Hardy Cross method: lock joints, compute fixed-end moments, release joints one by one distributing unbalanced moment by stiffness (distribution factors) and carry over half to far ends; repeat until negligible. Practical hand method for continuous beams and frames.
A three-span beam balances in around 4 cycles.
Moment distribution solves continuous beams and frames by balancing moments at joints, which gives accurate results with simple arithmetic.
Iterative method balancing joint moments in continuous beams.
Moment distribution solves continuous beams and frames by balancing moments at joints, which gives accurate results with simple arithmetic.
The fraction of an unbalanced moment that a member takes at a joint, based on its relative stiffness.
The part of a moment that is transferred to the far end of a member, which is usually half for a prismatic member with a fixed far end.
Typical applications include analysing a continuous floor beam with many spans by hand, checking the moments in a building frame before computer analysis and estimating the effect of a changed stiffness on the moments in a beam.
Study "Slope-deflection method" first (topic 45 of 112 in Civil & Structural). It covers the groundwork this topic builds on.
Distribution factor=k/Σk. Carry-over factor 0.5. Converges quickly.
A three-span beam balances in around 4 cycles.
The next topic is "Matrix stiffness method", which builds directly on this one.
It is classed as Intermediate in Civil & Structural (topic 46 of 112). It is an intermediate topic. Work through the beginner topics in Civil & Structural first.
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