变截面钢管混凝土格构柱抗震性能试验研究

为研究变截面钢管混凝土格构柱的抗震性能，以缀管布置形式和柱肢倾斜度为试验参数，对7根变截面钢管混凝土格构柱进行了水平低周反复荷载试验，分析了该类柱的破坏模式、滞回曲线、骨架曲线、延性、耗能、承载力退化、刚度退化和变形恢复等。研究结果表明：变截面钢管混凝土格构柱试件的破坏形态基本相同，均为整体压弯破坏；滞回曲线较饱满无明显捏缩，具有良好的抗震性能；随着柱肢倾斜度的增大，格构柱的水平承载力和耗能能力有一定程度提高，刚度退化率略有增加。缀管布置形式对格构柱位移延性的影响较大；与平缀管式钢管混凝土格构柱相比，斜缀管式钢管混凝土格构柱的初始刚度和水平峰值荷载明显增大，耗能能力略有降低，承载力退化更为明显。

Experimental research on seismic performance of variable cross-sectional concrete filled steel tubular laced columns

Horizontal low cyclic loading tests of seven variable cross-sectional concrete filled steel tubular (CFST) laced columns with experimental parameters of longitudinal slope and arrangement type of lacing tubes were carried out by quasi-static test method in order to learn their seismic performance. Based on test results, the rules of failure mode, hysteresis loop, skeleton curve, ductility, energy dissipation, strength degradation, stiffness degradation and deformation recovery capability of specimens were researched. Test results indicate that hysteresis loops of specimens are plump without obvious pinching, and they have good seismic performance. The failure mode of specimens are basically the same integral bending failure. With the increase of longitudinal slope, the horizontal load carrying capacity of laced column increases, energy dissipation capacity improves, and stiffness degradation rate increases slightly. The influence of arrangement type of lacing tubes on displacement ductility is relatively big. Compared with CFST laced columns with flat lacing tube, CFST laced columns with inclined lacing tube have larger initial stiffness and horizontal peak load, smaller energy dissipation capacity and more obvious strength degradation.