Steady-state limit of elastoplastic trusses for the plastic shakedown region

For elastoplastic trusses under quasi-static cyclic loading, a method is pr esented for finding the steady-state limit that bounds the plastic shakedow n and ratchetting regions. In the plastic shakedown region, an assumption e mployed in the previous approaches for finding the steady-state limit can b e invalid in many circumstances. Although strain reversals were assumed to occur only at load reversals, yielding of an element exhibiting plastic sha kedown may cause strain reversals in other elements. This difficulty is ove rcome by relaxing this assumption so that the strain reversals due to yield ing are taken into account. Numerical examples showed that the present meth od can find the steady-state limit even when strong effects of geometrical nonlinearity exist.