Flexibility — where it appears
Named by 2 essays across one field — each of them below, with the objects they name alongside it.
The theorem that swaps the question round
Push here and measure there; push there and measure here. The two readings are identical, for every elastic structure, whatever its shape — and that fact turns an influence line into something a model can be asked for directly.
The deflection that is a derivative
A structure's strain energy is one number. Differentiate it with respect to a load and out comes the displacement under that load — and the trick that makes it a method rather than an identity is that the load does not have to be there.
Named alongside it
The objects these essays reach for when they reach for this one.
CastiglianoComplementary energyDeflectionDummy loadInfluence lineLinearityMüller-Breslau's principleNumerical derivativeReciprocal theoremReciprocityRedundantStiffness