预应力钢带约束钢管混凝土叠合柱抗震性能试验研究

EXPERIMENTAL STUDY OF SEISMIC PERFORMANCE OF COMPOSITE COLUMNS WITH CORE STEEL TUBE AND CONFINED BY PRESTRESSED STEEL STRIPS

预应力钢带约束钢管混凝土叠合柱是充分利用钢管混凝土叠合柱和预应力钢带约束柱的优点所开发出来的具有良好抗震性能的新型组合柱,为探究钢管约束内部混凝土和预应力钢带约束外部混凝土对柱抗震性能的改善规律,开展4个预应力钢带约束钢管混凝土叠合柱试件和2个未采用预应力钢带约束的普通钢管混凝土叠合柱试件的拟静力试验,研究预应力钢带约束钢管混凝土叠合柱在低周反复荷载作用下的破坏机理、破坏形态、滞回性能、位移延性、骨架曲线、耗能性能、刚度退化以及钢带应变变化等受力性能,分析了钢带间距、箍筋布置对预应力钢带约束钢管混凝土叠合柱抗震性能的影响规律。研究结果表明:预应力钢带约束钢管混凝土叠合柱具有良好的延性、变形能力和耗能性能,相对普通钢筋混凝土柱和普通钢管混凝土叠合柱具有更加良好的抗震性能。

In order to take advantage of and improve the seismic performance of composite column with core steel tube,prestressed steel strips were adopted to confine the composite columns. And then a new type of composite column which composed of concrete filled core steel tube and confined by lateral prestressed steel strips was invented,which was abbreviated to PCFST column. In theory,the PCFST column may have good seismic performance and wide application prospect. In this paper,pseudo-static experiments of four PCFST columns specimens and two common CFST column specimens were conducted. According the experimental results of those four PCFST column specimens,the final failure pattern,hysteresis curves,skeleton curves of the specimens were fully analyzed. And a series of seismic performance indexes of those specimens such as displacement ductility coefficient,energy consumption values,and equivalent viscous damping coefficient were examined. Furthermore,the influences on the seismic performance of composite columns of prestressed steel strip spacing were also studied. From the experimental results,it was concluded that seismic performance of PCFST columns had been successfully improved by the lateral prestressed steel strips.