矩形截面钢管尾矿砂再生混凝土柱抗震性能研究

为研究矩形截面钢管尾矿砂再生混凝土柱的抗震性能，设计并制作了6个该类柱试件并对其进行拟静力试验，变化参数为再生粗骨料取代率(0%，50%，100%)和轴压比(0.3，0.5)。观察了矩形截面钢管尾矿砂再生混凝土柱变形和破坏形态，分析了其滞回曲线、骨架曲线、承载力退化、刚度退化、延性及耗能能力等。采用ABAQUS软件对矩形截面钢管尾矿砂再生混凝土柱抗震性能进行有限元分析，并与试验结果进行对比，验证有限元模型的合理性。试验研究及数值分析结果表明：矩形截面钢管尾矿砂再生混凝土柱变形过程及破坏形态与普通钢管混凝土柱相似，表现为柱脚的鼓曲变形；轴压比为0.3时，再生骨料取代率为50%和100%的柱峰值荷载较取代率为0%的柱分别降低8.3%和13.1%；轴压比为0.5时峰值荷载较轴压比为0.3时降低约9%；平均位移延性系数接近2.7，说明其具有良好的变形能力；矩形截面钢管尾矿砂再生混凝土柱具有良好的抗震性能。

Study on seismic performance of rectangular concrete-filled steel tube columns made with tailings and recycled aggregates

In order to study the seismic performance of rectangular concrete-filled steel tube columns made with tailings and recycled aggregates, six specimens were designed and tested under lateral cyclic load. The changing parameters are replacement rate (0%, 50% and 100%) and axial compression ratio (0.3 and 0.5). The deformation and failure mode of the specimens were observed. The hysteresis curves, skeleton curves, bearing capacity degradation, stiffness degradation, ductility and energy dissipation capacity of the specimens were analyzed. Finite element models were established using ABAQUS and compared with the test results to verify the rationality of FE models. Experimental research and numerical analysis show that the deformation and failure modes of the specimens are similar to those of ordinary concrete-filled steel tube columns, which are uniformly represented by the bulging deformation of column foot. When the axial compression ratio is 0.3, the peak bearing capacity of specimens with 50% and 100% replacement rate of recycled aggregate is 8.3% and 13.1% lower than that with 0% replacement rate, respectively. When the axial compression ratio is 0.5, the peak bearing capacity of the specimen is about 9% lower than that with axial compression ratio of 0.3. The average ductility coefficient is close to 2.7, indicating that the specimen has good deformability. The seismic performance of rectangular concrete-filled steel tube columns made with tailings and recycled aggregates is proved favorable.