矩形钢管混凝土柱隔板贯通式节点核心区的抗震性能研究

Diaphragm-through connection between concrete-filled rectangular steel tubular column and steel beam has been recommended in domestic technical specification and increasingly used in structural engineering. The Hyogoken-Nanbu earthquake in 1995 proved that the shear failure in the panel zone is one of the major earthquake damage for diaphragm-through connection. However, it is still unable to fully understand the seismic performance of the diaphragm-through connection since the lack of seismic experimental data for shear failure in panel zone. The accuracy of calculation methods proposed by researchers for shear bearing capacity of diaphragm-through connection is also needed to be verified by the seismic experimental data. In this project, the seismic performance of diaphragm-through connection is studied by using low-reversed cyclic loading experiment and finite element analysis. It is aimed to obtain the shear force-shear deformation hysteresis curves and skeleton curves of diaphragm-through connections during four different stages, including elastic stage, yielding stage, hardening stage and failure stage. With these experimental and analytical data, the shear bearing capacity, ductility, energy dissipation, strength and rigidity degradation of diaphragm-through connections with shear failure in the panel zone are deeply investigated. These experimental and analytical data are also adopted to verify and improve the calculation method of shear bearing capacity of diaphragm-through connection so as to provide valuable guidance for the design and application of the diaphragm-through connection.

矩形钢管混凝土柱与钢梁连接的隔板贯通式节点，目前已在国内行业规程中推广和实际工程中应用。1995年日本阪神地震表明，节点核心区的剪切破坏是隔板贯通式节点的主要震害形式之一。然而，目前关于隔板贯通式节点核心区剪切破坏的抗震试验数据缺乏，尚无法全面掌握节点核心区剪切破坏模式下的抗震性能；国内外研究学者提出的节点抗剪承载力计算方法的准确性也有待试验数据验证。本项目通过低周反复荷载试验和非线性有限元模拟，考察节点核心区剪切破坏模式下，隔板贯通式节点在弹性、屈服、强化和破坏阶段的剪力-剪切变形滞回曲线和骨架曲线；对节点核心区抗剪承载力、剪切转角延性系数、耗能能力、抗剪强度和刚度退化进行分析，全面掌握节点核心区的抗震性能；并通过节点核心区抗剪承载力、剪力-剪切变形骨架曲线等试验数据验证和完善节点抗剪承载力计算方法，为隔板贯通式节点的应用和推广提供试验依据和技术支持。

结合矩形钢管混凝土柱隔板贯通式节点的静力拉伸试验进行非线性有限元模拟，研究了隔板贯通式连接中，钢管混凝土柱与钢梁受拉翼缘的连接性能；分析了钢管厚度、隔板厚度、透气孔直径、梁翼缘厚度等参数对节点抗拉承载力的影响；研究了隔板贯通式节点轴向拉力的传递机制；基于屈服线理论，提出了隔板贯通式节点抗弯承载力计算方法。设计并制作了矩形钢管混凝土柱隔板贯通式节点试件，进行低周反复荷载试验并对试验进行非线性有限元模拟。根据试验结果和有限元分析结果，得到了节点核心区剪切破坏模式下，隔板贯通式节点的剪力-剪切变形滞回曲线；对节点抗剪承载力、延性系数、耗能能力、抗剪强度和刚度退化进行分析，全面掌握了隔板贯通式节点核心区的抗震性能；总结了现有的隔板贯通节点核心区抗剪承载力计算方法，并阐述了相关的优缺点和适用性，在试验结果和有限元分析结果的基础上，建立了核心区钢管腹板和混凝土的抗剪计算模型，提出了钢管核心区钢管腹板与混凝土协同受力的节点核心区抗剪承载力计算方法。