核心型钢混凝土柱的轴压比限值试验研究

Limit value of axial compression ratio for CSRC columns

基于界限破坏时的内力平衡条件,推导了核心型钢混凝土柱轴压比限值的理论计算公式,计算分析了配钢率、混凝土强度等级、柱截面尺寸等因素对核心型钢混凝土柱轴压比限值的影响。进行了5个1/2比例模型柱试件的低周反复加载试验,验证了配置核心型钢对提高混凝土柱的抗震性能和轴压比限值的有效性。计算和试验结果表明,在混凝土柱中配置一定数量的核心型钢,可以有效提高轴压比限值。本文建议的方法可以较为合理地确定核心型钢混凝土柱的轴压比限值,供工程实践参考。

Based on the balancing condition of internal forces in the case of balanced failure, the theoretical calculation formulas of limit values of axial compression ratio for core steel reinforced concrete （CSRC） columns are derived, and the main parameters which affect the limit values of axial compression ratio of CSRC columns are analysed. The analysis results indicate that, if certain quantity of H steel is designed in the section core of a concrete column, the limit values of axial compression ratio can be effectively increased. Five rectangular core steel reinforced concrete （CSRC） columns have been tested under cyclic loading to investigate the effect of core steel on the seismic behaviour of the reinforced concrete columns under the high axial load. The comparison of the analytical results with experimental results of five CSRC columns indicates that with the increasing of the core steel content, the limit value of the axial compression ratio can be increased. The proposed method can reasonably determine the limit values of axial compression ratio of a core steel reinforced concrete column, and can be used as a reference in practical engineering.