Effect Of Composite Action On Seismic Behavior Of Connection With Opening On Beam Web

In recent years, steel moment-resisting frame, with excellent capability to resist the effect of earthquake, has been widely adopted in the buildings. However, a large number of steel Moment-Resisting Frames experienced brittle fractures at beam-to-column connections in 1994's Northridge earthquake and 1995's Kobe earthquake. Search for more reasonable new connections with good ductility was one of major jobs of seismic behavior of beam-column connections of Moment-Resisting Frame.The connection with opening on beam web is one of the new connections, and the failure mechanism and cutting parameter have been known. But all the study on connection with opening on beam web did not consider the effect of composite action of concrete slab. So this paper uses concept analysis, nonlinear finite element analysis and experimental analysis for studying effect of composite action on seismic behavior of connection with opening on beam web. The main work includes:(1) The concept analysis introduces effective width of steel-concrete composite beams, shear connectors and slip of concrete slab, and analyzes capacity of connection with opening on beam web with composite action, and studies effect of composite action to the development of plastic area, and analyzes cutting parameter connection with opening on beam web with composite action.(2) The nonlinear finite element analysis uses static analysis method to study effect of composite action on behavior of connection with opening on beam web. Firstly, this paper verifies finite element modeling method; Secondly, this paper models finite element model with opening on beam web with composite action, and studies capacity, the strain distribution on elastic-plastic stages and the development of plastic area, and compares behaviors between the connections with concrete slab and without concrete slab. It is concluded that plastic hinge of connections with opening on beam web stay away from weld with effect of composite action of concrete slab.(3) The experimental analysis mainly studies seismic behavior of connections with opening web with composite action. Firstly, this paper determines experiment program about connection with opening on beam web with composite action; Secondly, this paper describes experimental phenomena, and analyzes the development of plastic area on connection, hysteretic behavior and failure mode, and compares with nonlinear finite element analysis. With effect of composite action of concrete slab, it is concluded that plastic hinge of connections stay away from weld, and that the connections have excellent capability to resist the effect of earthquake.The method of research of this paper is validated by comparing nonlinear finite element analysis with experimental analysis. This paper takes great significance on the follow-up research and study of new connections.