In continuum mechanics, elastic shakedown behavior is one in which plastic
deformation takes place during running in, while due to residual stresses
or strain hardening the steady state is perfectly elastic.
Plastic shakedown behavior is one in which the steady state is a closed
elastic-plastic loop, with no net accumulation of plastic deformation.
In the case of the plastic shakedown, the continuum body seems in a stable
condition, but because of the internal work due to cyclic external force,
which might cause fatigue damege.
Ratcheting behavior is one in which the steady state is an open elastic-plastic
loop, with the material accumulating a net strain during each cycle.
