Deformation Characteristics of Beams and Beam-Columns Subjected to Nonstationary Loading History at Strain Hardening Region.

点击翻译按钮获取中文摘要

In this study, a cyclic plasticity model for elasto-plastic hysteretic behaviors of structural steel is employed. The model is constructed by the refinements of a multi surface plasticity model introduced by Petersson and Popov. This model is applied to mild steel and high strength steel. Using material property functions obtained, elasto-plastic finite element analyses are carried out for round-bar specimens subjected to repetitive tension- compression loading under controlled strain. By comparing the results with those of corresponding experiments, it is confirmed that the accuracy of the stress-strain relations calculated by means of the proposed model is good gnough from the engineering standpoint. In order to calculate M-<PHI> relations of beams and beam-columns by means of the proposed stress-strain odel, the tangent stiffness method introduced by Chen and Atsuta is employed with some amendments. JIS(Japanese Industrial Standards)-5 typespecimens were shaped from a H-shaped beam specimen. Material property functions were determined by a combination of tension tests and tension-compression tests. Distribution of residual stress was analyzed by the drilling method and a simple type distribution was assumed. The calculated M-<PHI> relations are compared with those obtained by experiments which the author has carried out and it is confirmed that the accuracy of the hysteretic M-<PHI> relations calculated by means of the proposed model is good enough from the engineering standpoint.