钢管约束再生混凝土柱的变形性能及承载力计算

Bearing capacity and deformation performance of recycled concrete confined steel tube column

为研究钢管约束再生混凝土柱的变形性能和承载力,以再生粗骨料取代率、钢管截面形式、套箍系数为主要参数,制作了33个柱试件进行轴压试验。试验结果表明:圆形截面柱呈腰鼓状斜剪压破坏,方形截面柱呈斜压破坏;钢管截面形式、套箍系数比再生粗骨料取代率对柱构件极限承载力和变形能力的影响更明显;圆形截面柱的承载力稳定性、变形能力、耗能能力要优于方形截面柱。利用现有规范计算方法进行承载力计算发现,DL/T5085-1999标准适用于圆形截面柱的轴压承载力计算,DBJ 13-51-2003、CECS 159:2004、GJB 4142-2000标准适用于方形截面柱的轴压承载力计算。

In order to research on the bearing capacity and deformation performance of recycled concrete confined by steel tube(RCCST) under the axial loading, 33 RCCST columns are designed for the axial compressive test by considering the variable parameters of recycled coarse aggregate replacement percentage, section type and confinement index. Test results indicate that failure patterns of circular steel tube and square steel tube are waist-shaped diagonal shear compression failure and diagonal shear failure, respectively. The impact of ultimate bearing capacity and deformation performance on recycled coarse aggregate replacement percentage is not great, but section type and confinement index have an obvious impact on them. Recycled concrete confined by circular steel tube(RCCCST) column has higher strength stability and higher energy dissipation capacity than recycled concrete confined by square steel tube(RCSSST) column. It is suggested that the bearing capacity of RCCCST column under axial compression can be designed with DL/T 5085-1999 and the bearing capacity of RCSSST column under axial compression can be designed with DBJ 13-51-2003, CECS 159:2004 and GJB 4142-2000.