Study On The Seismic Performance Of The Eccentrically Braced Steel Frame Structure

With the development of social economy and progress of technology, as a kind of good performance of steel building materials have been used more and more widely. Steel is isotropic, stable mechanical performance, high strength advantages. compared to concrete, masonry structure, steel construction with a spatial arrangement is flexible, convenient construction, seismic performance characteristics. Eccentrically braced steel frame structure is commonly used in steel structure system, compared with the pure steel frame structure, it has large resist lateral stiffness, the earthquake response are much smaller. Compared to the center support steel frame structures, the elastic stage of both the lateral stiffness are not significant, the earthquake response close to. But in the plastic stage, the eccentric braced steel frames yield,the lateral stiffness decline slowly, it protects effectively the security of the beam and column, and other major components.The paper is on the basis of the analysis in previous studies, mainly from the length of link beam and eccentric braced form two aspects to discuss the eccentrically braced steel frame structure seismic performance. This paper establishes four models, in which two are for V type braced t, and other two for D type braced, and every form of braced is divided into two different lengths of link beam (both the shear yielding type),Comparison of energy consumption between the same type of support beam length on seismic performance, with a length of link beam can be analyzed two kinds of braced structures on seismic performance.The paper adopts static pushover and nonlinear dynamic time-history analysis method for four models, according to the calculation of the output from the development of plastic hinges, the top displacement and base shear, floor displacement, the displacement between the layers and inter layer displacement angle, and so on four models of the earthquake response, and thus its seismic capacity to assess and compare.By the analysis it could be find:V type braced stiffness greater, more carrying capacity, but under the action of earthquake in its also bear seismic forces, D type braced stiffness, the seismic force is small, but its under the action of earthquake displacement and displacement angle are more larger, with the link beam length increasing, the stiffness of the two braced smaller, but the energy dissipation capacity in enhancing.