Link Beam Performance Study Of The Y-type Braced Steel Frame

Steel structures are playing more and more important role in modern structure withtechnology and economy development. All previous earthquakes were indicated that steelframe structures havc well resistant-seisinic behavior. But due to traditionalresistant-lateral systems, the resistant-lateral rigidity and ducility Of steel Structures can'tmeet resistant-seismic demand in the areas of high seismicityEccentrically braced steel frames is refined resistant-lateral system based onconcentrically braced frames. Its rigidity and ductility meet resistant earthquake ofstructure. Eccentrically braced steel frames combines the strength and stiffness ofconcentrically braced frames with the inelastic behavior and enengy dissipation ofmoment-resisting frames,In the seismic applications can provode high elastic stiffness andlarge inelastic energy disspation capacity,especially inelastic deformation of link beamsabsorbed the seismic energy. This is a very suitable structural for seismically activeregions. So based on the mechanism of energy-dissipation of eccentrically braced framessystem. The analyses of response and collapse mechanism of link beams under seismicloading are not only significant in theoretical aspect,but also important in practice.In order to study Y style eccentrically braced link beams of behavior under seismicloading, the calculated model of link beam is established. The hysteretic behavior of linkbeam failed in shear yielding mode is analyzed in detailed by using FEM with nonlinearshell element. The constitutive laws of steel adopted mixed harden model. The failuremechanism and the ability of link beam is achieved under earthquake. The factors andvaried rules influencing link beam failed in shear yielding mode is analyzed under cyclicloads. The relationship of link beam with H shaped section, a/t_w and h/t_w of web isobtained. The proposal and countermeasure for designing Y type eccentrically braced linkbeams is put up.