Analysis Of Web Height-thickness Ratio On Eccentrically Braced Frames Link

Moment resisting framing systems typically have sufficient energy dissipationcapacity to provide the required ductility and concentrically braced framing systemefficiently meet deflection limitations through truss action. The concept of eccentricallybraced framing system has been advanced as an alternative to the two conventionalframing systems in seismic application, which are promoted and developed quickly inthe United States, Canada, Japan and Europe. There are several applications of this newframing system in some of our developed cities as well, but all foreign designs. Thelatest Chinese “Technical Specification for Steel Structure of Tall Buildings (draft)” hasrevised the relevant provisions of eccentrically braced framing systems based on the“American Seismic Provisions for Structural Steel Buildings”. There are still somedifferences between our provision and the provisions of the developed countries. In orderto achieve the best economic benefits, the web slenderness limits for links in ourspecification is much larger than those in the foreign provisions.The web slenderness limits for links plays an significant role in structures. Atpresent, many domestic research results show that the web slenderness limits in our codeare not adequate or reasonable. To assess the rationality of the web slenderness limits forlinks in our code, the Chinese code JGJ99-2012, American code ANSI/AISC341-05,European code Eurocode8and Canadian code CSA S16-01were compared and analyzed,which provides a reference for the relevant design and research.A total of25tests were conducted through nonlinear finite element method to studythe cyclic loading performance of links in steel eccentrically braced frames. Theobjectives of these tests were to reevaluate web slenderness limits for links. Linkspecimens were constructed from five different height-web sections, all of Q235steel,with various lengths ranging from600mm to800mm. This thesis provides the data ofthese specimens and concludes with a number of design recommendations for links ineccentrically braced frames in our specifications.