高含钢率型钢混凝土压弯构件受力性能影响因素分析

以8个含钢率分别为13.12%和15.04%、截面尺寸为500mm×500mm的型钢混凝土柱水平拟静力加载试验为基础，分析轴压比、含钢率和配箍率对高含钢率型钢混凝土压弯构件荷载-位移骨架曲线的影响。利用有限元分析软件ABAQUS建立试验试件的非线性有限元分析模型，模拟试验骨架曲线，验证有限元分析模型的有效性。以含钢率、轴压比和配箍率为参数，对37个型钢混凝土压弯构件进行参数分析，建模时考虑了型钢和箍筋对混凝土的约束作用，分析各参数对含钢率在20%以内的型钢混凝土柱骨架曲线的影响。结果表明：随着轴压比的增大，不同含钢率试件的屈服点割线刚度、峰值荷载、极限位移和延性水平逐渐接近，高含钢率型钢混凝土柱的优势逐渐减弱；当设计轴压比小于1.2时，型钢混凝土柱试件均具有良好的延性；随着配箍率的增大，峰值荷载和峰值位移均增大，试件延性增大。

Analysis of parameters influencing on mechanical behavior of SRC column with high ratio of encased steel

Based on the test results of eight steel reinforced concrete (SRC) columns with 13.12% and 15.04% ratios of encased steel under constant axial load and quasi-static lateral loading, design parameters such as encased steel ratio, axial load ratio and transverse reinforcement ratio which influence the lateral load-displacement skeleton curve of SRC column with high encased steel ratio were discussed. The test specimens had a square cross section of 500 mm×500 mm. Nonlinear finite element models were built with analytical software ABAQUS. After comparison of test results with nonlinear finite element analytical results, the feasibility of nonlinear finite element model were validated. Parametric analysis of 37 SRC columns with encased steel ratios less than 20% was carried out. The effects of encased steel ratio，axial load ratio and transverse reinforcement ratio were discussed. The results show that with the increasing of the axial load ratio, the secant stiffness of yield point, ultimate capacity, ultimate displacement and ductility of all specimens are gradually closer, so that the advantages of SRC column with high encased steel ratio are decreased. When the design axial load ratio is less than 1.2, all the SRC columns have good ductility. With the increasing of the transverse reinforcement ratio, ultimate capacity, the corresponding displacement and ductility increase.