Concept

Robustness — where it appears

What is left when part of a structure is gone, which is decided by whether the load can find another route rather than by strength.

Named by 2 essays across 2 fields — each of them below, with the objects they name alongside it.

The property that appears in none of the equations

Ductility is in no design formula on this site. Every method on this site depends on it — and a brittle structure does not merely fail early, it makes the analysis wrong.

materials · ductility

The structure that survives losing a member

Every check in this collection asks what a structure carries. None of them asks what is left when part of it is gone — and two frames with the same members, the same weight and the same factor of safety can answer that question completely differently.

structures · robustness

Named alongside it

The objects these essays reach for when they reach for this one.

Ductility Alternative load path Brittle fracture Determinacy Load path Lower bound theorem Mechanism Moment redistribution Plastic hinge Progressive collapse Redundancy Rotation capacity

All concepts