A Simplified Method to Predict the Steady Cyclic Stress State of Creeping Structures

摘要

Simplified methods have been developed to find the long-term cyclic state of stress for structures that exhibit inelastic creep and are subjected to a short period cyclic loading. In the present work a new simplified method is presented which may be applied to cyclic loads having any period. The method is based on decomposing the residual stress in Fourier series. The various Fourier coefficients are computed, in an iterative way, by satisfying equilibrium and compatibility at a few time points inside the cycle. The whole numerical procedure is formulated within the finite element method and examples of various structures are presented.