钢管混凝土叠合柱-钢梁节点抗震性能研究

钢管混凝土叠合柱是以钢管混凝土为核心，在外围绑扎钢筋并浇筑混凝土而形成的一种构件。这类构件形式已经在国内数十座高层和超高层建筑中得到了应用。在实际工程中钢管混凝土叠合柱常和钢梁或混凝土梁连接形成梁柱节点。而目前关于钢管混凝土叠合节点抗震性能的研究还比较少。因此，开展该方面的研究具有重要的理论意义和工程应用价值。.本项目深入研究钢管混凝土柱-钢梁节点的抗震性能。开展该类节点在柱顶恒定轴压力、梁端往复荷载作用下的试验研究，分析节点的破坏形态、承载能力和内力、变形发展规律。建立考虑材料损伤和钢-混凝土相互作用的节点精细化有限元分析模型。分析重要影响因素，如核心区轴压比、节点核心区性质、连接构造、楼板等对节点抗震性能的影响。建立节点核心区剪力-剪切变形关系和梁端弯矩-转角关系滞回模型，建立基于纤维梁柱单元的宏观节点单元模型。在此基础上提出钢管混凝土叠合柱-钢梁节点的抗震性能评价方法以及设计建议。

Concrete-filled steel tube reinforced concrete (CFSTRC) column is consisted of concrete-filled steel tubular (CFST) column in the middle and reinforced concrete (RC) surrounded. CFSTRC columns have been used in several high-rise and super high-rise buildings in China, and they are usually connected to steel beams or RC beams in real buildings. Therefore it is of great importance to study the seismic behavior of CFDST column to beam joints..In this study, joint specimens consisted of CFSTRC column and steel beam are tested under cyclic loading at the ends of the beams and constant loading on the top of the column. The failure modes, the capacity, the internal force and deformation of the joints are investigated. A fine finite element analysis (FEA) model considering the cyclic characteristic of materials and the steel-concrete interaction is established. The parametric study is conducted by using the validated FEA model on some key parameters, such as the axial load level and properties of the panel zone, the connection details and the RC slab. The hysteretic models on the shear versus shear deformation relation of the panel zone as well as the moment versus rotation relation of the beam end are suggested. A joint macro element model is established based on these hysteretic models and the fiber element model. The seismic behavior of this kind of joints is fully assessed and some suggestions on the joint design are also proposed.