混凝土组合柱高温后轴压性能试验研究

针对RPC(活性粉末混凝土)管-混凝土组合柱(CFRT)这一新型组合结构的抗火性能开展试验研究.采用高温试验炉对7个大尺寸CFRT短柱进行升温试验及高温后的轴压试验，试验参数包括控制温度、配箍率和配箍方式.结果表明，CFRT高温下未发生爆裂现象；高温后的轴压承载力和刚度随试验温度的提高而降低，但具有相对较高的残余承载力；提高配箍率和采用双层配箍方式，有利于改善CFRT高温后的抗压性能；与已有的普通钢筋混凝土约束柱抗火试验结果相比较，CFRT具有更高的残余承载力比.CFRT具有优异的抗火性能.
Fire resistance of Concrete-filled RPC tube (CFRT) columns were investigated by experimental study. Seven large-scale CFRT specimens were performed by heating test and axial compression test after elevated temperature. The test parameters included control temperature, volumetric stirrup ratio and stirrup arrangement mode. The test results showed the spalling of concrete was not observed during elevating temperatures. The compressive performance of CFRT column after high temperature decreased with the rising control temperature. Both increasing the volumetric stirrup ratio and arranging double layers of spiral hoops were effective measures for improving the mechanical properties of the CFRT columns after high temperature. Compared with the existing test results, the residual load carrying capacity ratio of the CFRT after elevated temperature was higher than that of the ordinary steel-confined column. The CFRT columns exhibited excellent fire resistance.