Finite Element Analysis Of Mechanical Behavior Of Beam-to-Column End-Plate Connections In Steel Frame

The mechanical behavior of beam-to-column connections in steel frame affects the overall performance of the structure directly, and its reliability is the key to ensure the structural safety. In practical engineering, all connections are between the two states of the completely rigid and the ideal hinge, so the concept of semi-rigid connections is defined, the end-plate connection is a typical semi-rigid connection. Currently, end-plate connections are designed according to rigid connections in China, such an approach does not match with the actual situation and is not conducive to seismic. Domestic and foreign scholars have conducted a lot of experimental and finite element analysis on end-plate connections. However, there is not much research on the influence of the factors to the mechanical behavior and their relationship for extended-end-plate connections. In this paper, the extended-end-plate connections are researched systematically by using the method of finite element numerical simulation based on existing research.Firstly, the correctness and feasibility of the FEM method for the research on mechanical behavior with end-plate connections is verified by comparing FEA results with existing experimental study.Secondly, a series of finite element model is established with different plate thickness, bolt diameter, bolt pitch, beam height, the column web thickness, axial compression ratio and anti-slip coefficient, and each of these models are calculate and analyze by monotonic loading and cyclic loading. Then the influence of various factors to the mechanical behavior, hysteretic behavior and stiffness properties is analyzed systematically.Thirdly, the degree of influence with all combinations of factors at different levels to the ultimate moment capacity and initial rotational stiffness is analyzed by using the method of range analysis on orthogonal design, and the optimal level combination of various factors is identified. The approximate empirical formula for the influencing factors to the ultimate moment capacity or initial rotational stiffness is obtained by using the method of regression analysis on orthogonal design.