Plastic Adaptation of Structures under Stochastic Excitation

Abstract

Dynamic adaptation of plastic structures is considered, assuming that the loading process is described by a random function of time. Since classical shakedown theory fails under stochastic loading, the need to follow the evolution of plastic deformations and displacements is recognized. To this end, bounding theorems for plastic displacements are extended to treat random loading. The theory is explained with reference to a simple structural pattern, i.e., an elastic-plastic work-hardening shear frame. A practical example concerning damage to a structure in a seismic site is numerically treated, and the results are evaluated against aseismic standard codes.