型钢再生混凝土组合柱四折线恢复力模型研究

Research on four broken line-restoring force model of steel reinforced recycled concrete composite columns

基于型钢再生混凝土组合柱低周反复荷载试验,提出了可考虑组合柱开裂点、屈服点、峰值点以及极限点的骨架曲线计算模型,采用回归分析和理论推导相结合的方法确定了该计算模型中各特征点参数值和折线刚度值计算公式。在此基础上,结合组合柱的刚度特征和滞回特性,给出其刚度退化规律、卸载刚度计算公式以及相应的滞回规则,并建立了型钢再生混凝土组合柱四折线恢复力模型。结果表明,计算骨架曲线与试验骨架曲线吻合较好,该四折线恢复力模型较好地反映了组合柱在低周反复荷载下的恢复力特性和受力特征。

Based on the low reversed cyclic loading testes of steel reinforced recycled concrete composite columns,the skeleton curve calculation model of the composite columns was put forward,which included the cracking point,yield point,peak point and ultimate point of the composite columns. The feature points values and stiffness variation values of skeleton curve calculation model were determined through using the combining methods of the regression analysis and theoretical derivation. On this basis,according to the stiffness features and hysteretic characteristics of the composite columns,the stiffness degradation rules,unloading stiffness calculation formula and corresponding hysteresis rules of the composite columns were given. Finally,the four broken line-restoring force model of steel reinforced recycled concrete composite columns was established. The results show that the skeleton curves obtained by calculation are in good agreement with the theskeleton curves obtained by test. The four broken line-restoring force model well reflects restoring force features and mechanical characteristics of the composite columns under low reversed cyclic loading.