The Pseudo-Shakedown of Beams and Plates When Subjected to Repeated Dynamic Loads

Abstract

A conjecture is derived in this paper for the pseudo-shakedown phenomenon of beams and plates which strengthen with finite displacements when subjected to repeated dynamic transverse loads causing material plastic flow and permanent deflections. This behavior is illustrated for a fully clamped, rigid, perfectly plastic beam which is subjected to a repeatedly applied, rectangular-shaped pressure-time history at the midspan. It transpires that a curve divides the dynamic load magnitude-pulse duration time area into two regions where pseudo-shakedown may or may not occur. Another curve in the region where pseudo-shakedown does not occur identifies when the dynamic problem may be studied with a static analysis.