矩形钢管混凝土异形柱-钢梁框架节点受剪承载力研究

在矩形钢管混凝土异形柱-钢梁节点试验研究的基础上，对节点的破坏特征及影响因素进行分析，结果表明矩形钢管混凝土异形柱-钢梁框架节点的破坏模式主要是节点域发生剪切斜压破坏，其受力机理为钢桁架、混凝土主斜压杆和约束斜压杆的综合作用。在此基础上，将节点域抗剪贡献分为三部分进行研究，包括节点域钢管腹板的抗剪贡献、节点域混凝土主斜压杆的抗剪贡献和约束斜压杆的抗剪贡献。根据试验结果和力学分析，推导了节点区柱腹板剪力计算式；由虚功原理得出节点区混凝土约束斜压杆的承载力计算式；通过对试验数据的回归分析，得到核心区混凝土主斜压杆的承载力计算式；最后提出了矩形钢管混凝土异形柱 钢梁框架节点屈服剪力和极限剪力的计算式，该计算式不仅考虑了柱轴力对节点区实际受力状态的影响，而且考虑了钢管对混凝土的约束作用。对比结果表明，采用计算式得到的结果与试验结果吻合较好。

Shear capacity of joints between concrete-filled square steel tubular special-shaped columns and steel beams

According to the experimental research of the joints between concrete-filled square steel tubular special-shaped columns and steel beams, the factors which influence the failure features of the joints were analyzed. The results indicate that the typical failure mode is shear diagonal compression in the core of the joint. The shear mechanism is the combination of steel truss mechanism, the main compression strut mechanism and the confined compression strut mechanism of concrete. Based on the model, the shear capacity of the connection is divided into three parts: the contribution of steel tube webs, the contribution of the main compression strut in the concrete core, the contribution of the confined compression strut in the concrete core. Based on the analysis of the experimental results, the calculation model of the shear strength of web in panel zone was established. The formula for calculation of the shear capacity of the confined compression strut in the concrete core was proposed based on the principle of virtual work. Through regression analysis of the test data, formulas for shear capacity of the main compression strut in the concrete core were put forward. The calculation formulas of the yield and ultimate shear capacities of the connection were established. Not only the effect of axial compressive force of column, but also the confinement provided by steel tube for concrete was taken into account in the formulas. The formulas agree well with experiments data.