往复荷载作用下矩形钢管混凝土构件力学性能的研究

BEHAVIOR OF CONCRETE-FILLED STEEL RECTANGULAR HOLLOW SECTIONAL COLUMNS SUBJECTED TO CYCLIC LOADING

以往 ,国内外学者对矩形钢管混凝土构件滞回性能的研究尚少见报道。本文以矩形钢管混凝土构件截面高宽比和轴压比为主要参数 ,进行了 3 0个构件滞回性能的实验研究。利用数值方法分析了矩形钢管混凝土构件的滞回性能 ,理论计算结果与实验结果吻合较好。利用数值方法 ,系统分析和考察了轴压比、长细比、含钢率、截面高宽比、钢材屈服强度和混凝土强度等参数对滞回曲线骨架线的影响规律 ,在此基础上 ,提出了矩形钢管混凝土构件弯矩 -曲率和P -Δ滞回关系模型 ,以及位移延性系数的简化计算方法。

In the past,concrete-filled steel RHS(rectangular hollow section)columns subjected to the axial load and cyclically increasing flexural loading were Seldom studied.The flexural force-deformation behavior of concrete-filled steel RHS specimens was experimentally investigated and the results are presented in this paper.The parameters in the study included the depth-to-width ratio and the axial compressive force-to-axial compressive ultimate capacity ratio.Thirty concrete-filled thin-walled steel RHS specimens were tested under the constant axial load and cyclically increasing flexural loading.A mechanical model is developed in this paper for the concrete-filled steel RHS columns subjected to the constant axial load and cyclically increasing flexural loading.The predicted cyclic responses for the composite columns are in good agreement with the test results.Based on the theoretical model,the parametric analysis was performed on the behaviors of moment versus curvature response,lateral load versus lateral displacement relationship,as well as the ductility coefficient for the composite specimens.Finally,simplified models for the moment versus curvature response,and the lateral load versus lateral displacement relationship,and for the ductility coefficient are suggested.