为了研究地震作用下型钢高强高性能混凝土框架柱的损伤演化过程,通过改变轴压比、体积配箍率、含钢率、加载制度对12榀型钢高强高性能混凝土框架柱试件进行了低周反复加载试验,得到了试件经历不同次数循环加载后其极限承载、变形和极限耗能能力的变化规律,并从损伤的角度系统地分析了不同设计参数及加载制度对试件荷载-位移曲线、骨架曲线、刚度和强度退化、变形能力、滞回耗能等的影响。研究结果表明,试件的损伤过程可以分为无损、损伤稳定增长、损伤急剧增长三个阶段;随着循环次数和位移幅值的增加,试件损伤逐渐累积,使其刚度、强度不断退化,耗能能力以及极限变形能力不断降低;与变幅循环加载相比,常幅循环加载下试件的损伤演化过程较为缓慢,滞回耗能总量相对较大。研究结果为进一步建立能够描述型钢高强高性能混凝土框架柱损伤程度的地震损伤模型,揭示损伤对框架柱力学性能的影响提供试验支持。
Evolution of the damage of SRHSHPC frame columns was investigated through low cycle reversed loading experiments of 12 frame column specimens with various axial compression ratios, stirrups ratios, steel ratios and loading histories. The variations of the ultimate bearing capacity, ultimate deformation and ultimate hysteretic energy dissipation of specimens subjected to different numbers of cyclic loading were obtained. The influence of design parameters and loading history change on the loading-displacement curve, skeleton curve, strength and stiffness degradation, deformability and energy dissipation capacity were analyzed from the viewpoint of damage. The results show that the damage process of the specimens can be divided three stages: undamaged, gradual stable damage and rapid damage. With the increase of the number of cyclic loadings and displacement amplitude, the damage of the specimens accumulated gradually, which caused the strength and stiffness degradation and decrease of energy dissipation capacity and ultimate deformability. Comparing with the variation of displacement amplitude cycle loading, the process of damage evolution of the specimens was slower than under constant displacement amplitude cycle loading, and the total of energy dissipation of specimens was comparably larger. The study may provide support for establishing seismic damage model and revealing the effect of damage on the mechanical property of SRHSHPC frame columns.