方钢管混凝土柱-钢梁外环板式节点抗剪性能

摘要

为研究方钢管混凝土柱-钢梁外环板式节点抗剪性能,以钢管混凝土柱节点试验尺寸为参照,建立方钢管混凝土柱-钢梁外环板式节点在往复荷载作用下的精细有限元分析模型.该模型考虑材料非线性、混凝土材料在循环荷载下的损伤退化、钢和混凝土之间的相互作用等因素的影响.通过与试验结果进行对比分析,验证该有限元模型具有较好的精度和可靠性.此后研究柱宽厚比、核心混凝土强度、轴压比和节点核心区高宽比等因素对节点的影响,提出一种方钢管混凝土柱-钢梁外环板式节点的核心区剪力-剪切变形恢复力模型.研究结果表明,该模型具有实用性,可为工程设计提供实际依据.%Detailed finite element analysis (FEA) model was established to investigate the shear performance of square concrete-filled steel tubular (CFST) column to steel beam joint with external diaphragm under seismic loading on the basis of the size of the joint in test. The material non-linearity, the damage degradation of concrete under cyclic loading and the interaction between steel and concrete were considered in this model. Experimental result was compared to validate the feasibility of this model in simulating the behavior of the composite joints in cyclic loading. Simultaneously, parametric studies were carried out to study the influence of the following parameters on the shearing capacity and deformation in panel zone: ratio of width to thickness of column, the concrete strength of panel zone, the axial load ratio of the column and the ratio of depth to width of panel zone. Eventually, a shear force-deformation restoring-force model of panel zone in composite joints was proposed. The results show that the restoring-force model is practical and can provide practical basis for engineering design.