不锈钢管超高性能混凝土柱抗震性能研究

Study on seismic behavior of ultra-high performance concrete filled stainless steel tubular columns

为探究不锈钢管超高性能混凝土柱(ultra-high performance concrete filled stainless steel tube, UHPCFSST)的抗震性能,研究长细比、轴压比、径厚比和内置钢骨参数的影响,对6根UHPCFSST柱试件进行水平低周往复荷载作用下的拟静力试验,实测试件的滞回曲线,观察试件破坏形态,分析各参数对试件滞回性能、刚度、延性和耗能能力的影响规律。试验结果表明:试件的破坏形态基本呈现为柱底灯笼状鼓曲破坏,并伴随钢管撕裂以及混凝土压溃。此外,在4个单参数对比分析中,加入钢骨和减小径厚比能显著提高试件的延性和水平极限承载力;随着长细比的增加,试件延性得到一定提升,但水平极限承载力有所下降;在一定范围内,轴压比的增加会降低试件的水平极限承载力。

In order to study the seismic behavior of ultra-high performance concrete filled stainless steel tube(UHPCFSST),the effects of length to slenderness ratio, axial compression ratio, diameter to thickness ratio and built-in steel bone parameters were investigated by conducting pseudo-static tests on six UHPCFSST columns under horizontal low circumferential reciprocal loads.The hysteretic curves of the specimens were measured, the failure forms of the specimens were observed, and the influences of various parameters on the hysteretic properties, stiffness, ductility and energy dissipation capacity of the specimens were analyzed.The test results show that the damage of the specimens is basically in the form of lantern-shaped bulging damage at the bottom of the column, tearing of the steel pipe and crushing of the concrete.In addition, in the four single-parameter comparative analysis, adding steel bones and reducing the diameter to thickness ratio can significantly improve the ductility and horizontal ultimate bearing capacity of the specimens;with the increase of the length to slenderness ratio, the ductility of the specimens is improved to some extent, but the horizontal ultimate bearing capacity decreases;within a certain range, the increase of the axial compression ratio will reduce the horizontal ultimate bearing capacity of the specimens.