【摘要】 研究了由同心设置的内、外圆钢管构成的轴心受压双钢管混凝土短柱正截面受压承载力,分析了单钢管混凝土柱与双钢管混凝土柱的受力机理,并根据纤维模型法原理,采用适用于钢管混凝土受力特性的钢材与混凝土材料本构关系,给出了轴心受压双钢管混凝土短柱的荷载-位移全过程数值分析和正截面承载力计算公式。进行了5个双钢管混凝土短柱的轴心受压试验,验证理论分析的正确性。理论分析与试验研究表明:轴心受压双钢管混凝土短柱与单钢管混凝土柱的受力全过程都可以分为弹性阶段、弹塑性阶段和破坏阶段。双钢管混凝土短柱的破坏形态为腰鼓形,其外层混凝土的工作性能与单钢管中的混凝土大致相同,但内钢管中的内层混凝土受到的约束效应较大,且不是内、外钢管对它的约束效应的叠加,因此对内层混凝土约束效应的确定是计算承载力的关键。通过与相同含钢率的轴心受压单钢管混凝土短柱受力过程的对比得出:双钢管混凝土柱的承载力明显高于单钢管混凝土柱,且具有非常好的延性和整体性。更多还原

【Abstract】 This paper studies the normal cross-section load-carrying capacity for the concrete-filled double steel tubular short columns subjected to axial compression load in which the inner and outer circle steel tubes are placed with the same circle center.The working mechanics of the concrete-filled single steel tubular and double steel tubular short columns are analyzed based on the fiber model method and the suitable constitutive relationship.The paper provides the load-displacement numerical analysis and the calculation formula of load-carrying capacity for the concrete-filled double steel tubular short columns subjected to axial compression load.The specimens of concrete-filled double steel tubular short columns subjected to axial compression load were tested and compared favorably with proposed analytical method.Both analysis and test showed that the concrete filled double steel tubes subjected to axial compression load behaved similarly as conventional concrete filled tube,with the elastic stage,elastic-plastic stage and failure stage.The failure pattern of the concrete filled double steel tubular short column exhibited mid-height drum shape.The working performance of its outer layer concrete is approximately the same as that in concrete-filled steel tubular short column,but the confinement effect to the concrete in the inner steel tube is larger.Comparing with the concrete-filled steel tubular short columns,the load-carrying capacity,ductility and integral property of the concrete-filled-double steel tubular short columns are better.更多还原