Moment Distribution Method

What is Moment Distribution Method?

An iterative hand-calculation method, developed by Hardy Cross in 1930, that solves indeterminate beams and frames by repeatedly balancing and redistributing moments at each joint until the structure converges toward equilibrium. It let engineers analyse complex frames accurately decades before computers made direct matrix solutions routine.

The five clues

Engineerdle #35 described Moment Distribution Method with five clues, revealed one at a time from hardest to most direct. Each clue points at a different property of the concept.

1. 01A hand-calculation technique from an era before computers did the work.
2. 02It solves an indeterminate frame by an iterative process of balancing.
3. 03Fixed-end moments get released a joint at a time and redistributed.
4. 04Each iteration gets you closer to the true answer, without ever solving simultaneous equations directly.
5. 05Developed by Hardy Cross in 1930 to analyse indeterminate beams and frames without solving simultaneous equations.

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