节能砌块隐形密框复合墙体双面受火后滞回特性研究

Study on the hysteretic behavior of energy-saving block and invisible multi-ribbed frame composite wall subjected to double-side fire

为了评价节能砌块隐形密框复合墙体(以下简称复合墙体)受火后的滞回特性,制作了6个缩尺比例为1∶2的试件,并对试件进行了双面受火试验和受火后平面内循环往复加载试验,研究了轴压比、受火时间对墙体骨架曲线及滞回特性的影响。基于试验结果和现有恢复力模型理论,考虑轴压比和受火时间影响,提出了适用于受火后墙体试件的退化四线型恢复力模型。相关计算分析结果表明:计算得到的骨架曲线与试验情况以及计算得到的恢复力模型与墙体滞回曲线吻合程度均较好,表明提出的恢复力模型可较好地反映轴压比和受火时间对其滞回特性的影响,可为该墙体的结构弹塑性分析及工程应用提供参考。

In order to evaluate th hysteretic behavior of the energy-saving block and invisible multi-ribbed frame composite wall(composite wall)after fire,six 1∶2 reduced scale specimens were prepared.And the specimens were tested under double-sided fire and subjected to an in-plane cyclic load.The influences of axial compression ratio and fire time on the skeleton curve and hysteretic characteristics of the composite walls were studied.According to the test results and the existing theory of restoring force model,a regressive four-fold line restoring force model suitable for the walls considering the influence of axial compression ratio and fire time was proposed.The relevant calculation and analysis results show that the calculated skeleton curve is in good agreement with the experimental skeleton curve.The calculated restoring force model is consistent with the hysteresis curve of the wall,which shows that the proposed restoring force model can better reflect the influence of the axial compression ratio and the fire time on its hysteretic characteristics,and can provide reference for structural elastic-plastic analysis and engineering application of the wall.