为研究钢管高强混凝土组合柱的轴心受压承载力,完成了18个组合柱试件的轴压试验。试件的主要变化参数有:钢管混凝土套箍指标、管外混凝土强度和箍筋配箍特征值。试验结果分析表明,峰值承载力前和达到时,钢管和管外钢筋混凝土纵向变形一致;管外钢筋混凝土破坏后,核心的钢管混凝土提供了较大的后期强度和轴向变形能力;钢管混凝土的套箍指标、管外混凝土的强度和箍筋配箍特征值是影响组合柱轴压承载力的主要因素。试验结果进一步验证了《钢管混凝土叠合柱结构技术规程》(CECS188:2005)给出的组合柱轴心受压承载力计算公式同样适用于钢管高强混凝土组合柱。
To study axial compressive strength of high strength concrete-filled steel tube composite columns,tests of 18 specimens were carried out.Parameters of the specimens were the confinement index of concrete-filled steel tube,the cubic strength and the stirrup characteristic value of concrete outer of steel tube.Test results show that the concrete-filled steel tube and the reinforced concrete deform simultaneously in the axial direction before and at the peak value of axial compressive force.After failure of the reinforced concrete,the concrete-filled steel tube can still bear the axial load and deformation.The main influential factors of axial compressive capacity are confinement index,the cubic strength and the stirrup characteristic value of concrete outer of steel tube.The accuracy of the formula of axial compressive strength of composite columns provided by CECS188:2005 was proved by the test results and related references.