Experimental Research And Finite Element Analysis On The Lateral Resistant Performance Of Steel Braced Frame

Steel structures are playing more and more role in modern structure with technology and economy. All previous earthquake were indicated that steel frame structures have welL resistant-seismic behavior But due to traditional resistant-lateral systems, the resistant-lateral rigidity and ductility of steel structures can't meet resistant-seismic demands.Eccentrically braced frames (EBFs) combines the strength and stiffness of concentrically braced frames (CBFs) with the inelastic behavior and energy dissipation of moment-resisting frames, especially inelastic deformation of link absorbs seismic energy. It is a kind of refined resistant-lateral system. So, the analysis about response and collapse mechanism of EBFs under seismic loading are not only significant in theoretical aspect, but also important in practice.Based on the questions that elaborated, two l:2-scale steel frame specimens are tested in this paper-EBFs and CBFs. Studied the resistant-lateral capability of EBFs and CBFs under cycle loading. Analyzed the stiffness , strength , ductility and dissipation of frame, etc. The performance and validity of CBFs and EBFs are evaluated and their design method and course is presented on the basis of the experimental research and analysis.Nonlinear analysis are conducted on CBFs and EBFs with numerical technology in this paper, discussed stress of frame under varial loading conditions. Link can dissipate 90 percent of seismic energy. It is the key of EBFs, therefore, furthermore calculation about link are carried out in this thesis, introduced achieved research, summarized the affect of link on whole capability in the first, the second, numerical calculation are proceeded on link with ANSYS: with the purpose of discussing yieldingmode critical length of link, established five different specimens; with the purpose of discussing the influence of h/tw of web, b/tf of flange and h/b, established eighteen different specimens; with the purpose of discussing the affect of stiffener, established four different specimens, and elaborated the affect of stiffener on link based on achieved test researches.Some problems about this research that ought be studied were put forward in the end of this thesis.