Experimental Research on Seismic Behavior of Cold-Formed Thin-Walled Square Steel Tube Beam-Column Connection with Welded Haunch
Zhang Chuntao1 Li Zhengliang1, 2 Wang Ruheng3 Jian Bin1,3
1. School of Civil Engineering, Chongqing University, Chongqing 400045, China; 2. Key Laboratory of New Technology for Construction of Cities in Mountain Area (Chongqing University), Ministry of Education, Chongqing 400045, China;3. School of Civil Engineering and Architecture, Southwest University of Science and Technology, Mianyang 621010, China
Abstract:Abstract: The cold-formed thin-walled square steel tube has been widely applied in post-seismic reconstruction area after the Wenchuan earthquake. As there are no detail design instructions of this structure, it demands a further study for connection mode and mechanical properties of cold-formed thin-walled steel beam-column connection. The tridimensional double connections model is proposed according to the actual building structure. By using cycling loading test two types of full-scale beam-column connections (8 specimens) under different axial compression ratios are studied, four connections are welded haunch slabs, and the others are not. According to the comparison of the results, failure modes and hysteretic curves of connection with welded haunch are obtained. Moreover, main parameters for estimating earthquake resistant behavior of connection with welded haunch are studied, such as load-carrying capacity, ductility ratio, stiffness degenerated, and energy dissipation coefficient. Meanwhile, ANSYS nonlinear finite element models are used to analyze the seismic behavior of the connection, and the results are also compared with the experimental results. The research shows that: Analytical results agree well with experimental results, and the theoretical analysis has been approved correctly. The ultimate failure of connection with welded haunch is caused by the local buckling of beam, and the yield surface is almost located at outside of connections. The connection with welded haunch can experience much cycling time, which has longer yield platform after yield, stronger cumulative energy dissipation capacity and better ductility. This can make connection to consume much energy in earthquake and meet the need of seismic design very well.