内藏钢管超高强混凝土芯柱组合柱抗震性能试验研究

结合6个内藏钢管超高强混凝土芯柱组合柱试件和2个普通钢筋混凝土柱试件的低周反复加载拟静力试验，对内藏钢管超高强混凝土芯柱的组合柱的破坏形态、破坏机理和抗震性能开展研究，重点对箍筋布置和预应力钢带布置对组合柱抗震性能的影响进行分析。通过分析实测荷载-侧移滞回曲线，对试件的延性性能、耗能性能、刚度退化和强度衰减等抗震性能指标进行了对比分析。研究结果表明，内藏钢管混凝土芯柱可以明显提高柱的延性性能及耗能性能，加密箍筋和采用预应力钢带可以对组合柱产生有效约束，进一步提高内藏钢管混凝土芯柱组合柱的延性性能、耗能性能，改善其刚度退化、强度衰减。

EXPERIMENTAL STUDY ON SEISMIC PERFORMANCE OF COMPOSITE COLUMNS WITH HIGH STRENGTH CONCRETE FILLED STEEL TUBE CORES

Through the cyclic loading pseudo-static experiments of six composite columns with ultra high strength concrete filled steel tube (CFST) cores and two conventional reinforced concrete columns, the failure pattern, failure mechanism and seismic performance of the CFST core columns were thoroughly investigated. The effects of the stirrup arrangement and the layout of prestressed steel strips on the seismic performance of the composite columns were critically examined. On the basis of the measured load-lateral displacement hysteresis curves, the seismic behavior such as the ductility, energy dissipation, stiffness and load-bearing capacity were analyzed. The results show that the CFST column exhibits outstanding ductility and energy dissipation performance as compared to the conventional ones. By means of reducing the stirrup spacing and using prestressed steel strips, the CFST core columns can be effectively confined, leading to enhanced ductility, energy dissipation, stiffness and load-bearing capacity.