高温后矩形钢管混凝土双向压弯构件力学性能试验研究

Experimental study on behavior of concrete-filled rectangular steel tubular (CFRST) columns subjected to biaxial compression and bending after high temperature

设计了双向压弯构件试验加载和量测装置;对14根高温后矩形钢管混凝土双向压弯构件的残余力学性能进行了试验测试;并对温度、长细比、加载偏心角度、截面高宽比和套箍系数等参数进行了研究。研究发现,温度、长细比、加载偏心角度、套箍系数、截面高宽比是影响高温后矩形钢管混凝土双向偏压构件承载力及延性的主要因素,高温后该类构件仍有较高承载力,所有试件的位移延性系数平均值大于8,表明高温后矩形钢管混凝土双向压弯构件具有较好的延性。

In this paper, a set of test apparatus was first developed and designed to load and measure structural response. Fourteen concrete filled rectangular steel tubular （CFRST） columns subjected to biaxial compression and bending, were tested after high temperature exposure. The research emphasized in studying the effects of experimental parameters, such as temperature, slenderness ratio, eccentric angle, height-to-width ratio and confining coefficient. The results show that the bearing capacity and ductility are mainly influenced by the testing parameters, and types columns. After high temperature, the column still had good bearing capacity. The average ductility factors of all specimens were over 8, this indicates that CFRST columns subjected to biaxial compression and bending has good ductility even after high temperature exposure.