Stiffness ratio — where it appears
Named by 2 essays across 2 fields — each of them below, with the objects they name alongside it.
The torsion that goes away if you let it
A spandrel beam attracts a torque in proportion to its own torsional stiffness. Crack it and the stiffness falls by a factor of four, the torque falls with it, and nothing has failed — because the floor beam it was competing with picks up exactly what was shed. A canopy hung off the same spandrel is a different animal entirely.
The arm that makes the columns work
The perimeter columns of a tall building are already there, already carrying gravity, and already the furthest thing from the centre. They take almost none of the overturning, because a floor slab transmits shear and not moment — and one storey-deep arm at the right height changes that by nearly a half.
Named alongside it
The objects these essays reach for when they reach for this one.
CompatibilityCompatibility torsionCoreCracked sectionDifferential shorteningDistribution factorDriftEquilibrium torsionFixed end momentJoint stiffnessLateral systemLoad path