Experimental Study and Finite Element Analysis of the Seismic Behaviors for Steel Fiber Reinforced High-strength Concrete Frame Exterior Joints

Based on the experimental results of three steel fiber reinforced high-strength concrete frame exterior joint under the low cycle loading, the numerical simulation by nonlinear finite element method was adopted to analyze their behaviors and to explore the influence of axial compressive ratio on seismic capacity of the joint. The results indicate that the increase of the axial compressive ratio enhances the restriction role to the joint core area concrete, slows down the degeneration degree of shearing-resistance capacity and stiffness, enhances the shearing-resistance capacity of the core area, the joint ductility and the energy dissipation capacity. The finite element analysis coincides well with the experimental results. In finite element analysis, steel fiber was equated with micro-reinforcement, and then put evenly into the concrete unit. Compared with the test results, the method of taking the steel fiber and concrete as a holistic model was thus validated.