混凝土异形柱-钢梁装配式节点受剪性能试验研究

Experimental study on shear behavior of prefabricated joints between special-shaped concrete column and steel beam

为研究混凝土异形柱-钢梁装配式框架节点核心区的受剪性能,按照预制混凝土异形柱中预埋钢牛腿节点未加强、增配X形筋、增配X形钢板三种方式,分别制作3个预制混凝土异形柱-钢梁节点试件进行拟静力试验,得到其破坏特征、承载力、滞回曲线、刚度退化、耗能能力等抗震性能指标。由节点剪切变形、节点区钢筋应变、钢板应变测量结果,分析了不同牛腿加设方式对节点核心区受力性能的影响。结果表明:试件位移延性系数在3.22~5.94之间,破坏时位移角都超过1/50,抗震性能良好;牛腿内侧加设的X形钢筋与X形钢板均与节点核心区混凝土协同受力,可有效提高节点核心区受剪承载力。采用有限元软件ABAQUS对采用X形钢板增强的试件进行了数值模拟和参数分析,依据试验分析结果,推导出X形钢板增强的预制异形柱-钢梁混合装配式框架节点核心区受剪承载力计算公式,计算结果与试验实测值和有限元模拟值吻合较好。

In order to study the shear behavior of the core area of special-shaped concrete column to steel beam frame joints,the quasi-static testing of three special-shaped precast concrete column to steel beam frame joints which the steel corbel in the prefabricated special-shaped column is respectively not embedded and embedded with the X-shaped reinforcement and the X-shaped steel plate was carried out.The damage characteristic and the seismic performance indexes such as bearing capacity,hysteretic curve,stiffness degradation and energy dissipation capacity were obtained.The influence of different ways of adding steel corbel on the mechanical behavior of the core area of joints was analyzed in terms of the shear deformation,strain of reinforcement and steel plate in joint area.The experimental result shows that the displacement ductility coefficients of the specimen are between 3.22 and 5.94.The displacement angle is more than 1/50 at the time of failure and the seismic performance is good.The X-shaped reinforcement and X-shaped steel plate embedded in the corbels can work coordinately with the concrete in the joint area so that the shear capacity is improved effectively in the core area of joints.The numerical simulation and variable parametric analysis of joint strengthened with X-shaped steel plate were carried out by the finite element software ABAQUS.The formula for calculating the shear capacity of the precast concrete special-shaped column to steel beam frame joint was derived according to the test and analysis results.The calculated results are in good agreement with the experimental results and the simulated values of the finite element analysis.