双向荷载作用下方钢管混凝土柱-组合梁空间节点抗震性能试验研究

Research on seismic responses of 3D joints with CFT column and composite beam under bi-directional loading

完成3个方钢管混凝土柱-组合梁空间节点模型的抗震性能试验,重点研究不同加载路径下空间组合节点的受力特征、滞回性能和破坏机理,比较平面加载组合节点和空间加载组合节点的受力特征,分析双向加载作用的耦合关系。结果表明,双向受力对钢管混凝土柱-组合梁节点的承载力、变形、延性以及刚度、强度退化等性能有较大影响;与平面内加载的组合节点相比,双向加载条件下空间组合节点的承载力最多可降低20%,延性降低10%;由于双向荷载的相关作用,梁变形在总变形中所占的比例有所降低,而柱变形及节点域剪切变形所占的比例增大,在节点核心区受剪设计时应考虑双向受力的不利影响。

This paper presented the details and results of the experiments on three composite joints that consist of composite steel-concrete beams and concrete filled tubular columns with square cross-section.The effects of bi-directional or unidirectional hysteretic loading regimes on strength,deformation and energy dissipation capacities were investigated.The test results show that the seismic responses of 3D composite joints are influenced significantly by different loading paths.Compared with 2D composite joints,the load carrying capacity and ductility of 3D composite joints decrease about 20% and 10% respectively,and the contribution of beam deformation to the overall specimen displacement also decreases due to the coupling effects in the columns and joint cores under bi-directional loading.