反复荷载下圆钢管型钢再生混凝土组合柱恢复力模型研究

Restoring force model of steel reinforced recycled concrete filled circular steel tube composite columns under cyclic loading

为建立圆钢管型钢再生混凝土组合柱的恢复力模型,对11根圆钢管型钢再生混凝土组合柱试件进行了低周反复荷载试验研究,考虑了再生骨料取代率、配钢率及钢管径厚比等不同设计参数的影响,分析了组合柱的地震破坏形态及滞回性能。基于组合柱的力学特征及曲线形状,提出了圆钢管型钢再生混凝土组合柱骨架曲线的三折线参数模型,采用理论推导与数据拟合的方法确定了组合柱骨架曲线的模型参数。在此基础上,给出了组合柱的滞回规则和卸载规律,构建了组合柱的恢复力模型,计算滞回曲线与试验滞回曲线吻合良好,表明该恢复力模型较好地反映了反复荷载下组合柱的受力特征点及滞回性能,可为此类组合柱的推广提供技术参考。

To establish the restoring force model of circular steel tubular composite columns filled with steel reinforced recycled concrete,11 specimens of the composite columns were tested under low cyclic loading.Considering the influence of different design parameters such as recycled aggregate replacement rates,steel ratio and diameter thickness ratio of the steel tubes,the seismic failure modes and hysteretic behaviors of composite columns were analyzed.Based on the mechanical characteristics and curve shapes of composite columns,a three-fold-line parameter model of the skeleton curves of composite columns was proposed,and the model parameters of the skeleton curves model are determined by theoretical derivation and data fitting.On this basis,the hysteresis rules and unloading law of the composite columns are established,and the restoring force model of composite column is constructed.The calculated hysteretic curve is in good agreement with the measured hysteresis curve,which shows that the restoring force model better reflects the stress of the composite columns under repeated loading feature points and the hysteretic performance,and can provide technical reference for this kind of composite column promotion.