钢管混凝土哑铃形短柱轴压试验研究

进行了10根钢管混凝土哑铃形轴压短柱的试验。试验参数为两管间距、腹板间距以及腹板有无拉杆加劲。分析了构件的破坏机理、荷载-位移曲线、圆管与钢腹板的荷载-应变曲线和荷载-组合材料泊松比曲线。分析结果表明,在哑铃形轴压构件中的圆钢管混凝土与单圆管钢管混凝土的受力性能基本相同,腹腔内的混凝土有受到约束作用,钢腹板与圆钢管交接处的焊缝开裂是构件最后破坏的主要特征。在试验分析的基础上,提出了钢管混凝土哑铃形轴压短柱承载力的简化计算方法。

EXPERIMENTAL STUDY OF CONCRETE-FILLED STEEL TUBULAR DUMBBELL SHAPED SHORT COLUMNS UNDER CONCENTRIC LOADS

concrete-filled steel tubular (CFST) dumbbell shaped columns under concentric loads are tested. The distance between two tubes and the distance between two webs with or without tie rod to connect the two webs are taken as experimental parameters. The load-displacement relations and the failure mechanisms of the specimens, the load-strain relations of both circular steel tubes and steel webs, and the load-Poisson抯 ratio relation of the composite material are analyzed. Experiment results indicate that the property of the circular CFST in the dumbbell shaped member is the same as a concentrically-loaded CFST single tubular column. The concrete inside the web space is also constrained by the link steels. The rupture of welding seam connecting the web plates and the steel tube is the most pronounced failure mechanism. A simple calculation method for the ultimate load of dumbbell shaped CFST concentrically-loaded columns is proposed.