104 / 2016-12-03 23:05:12

Seismic Performance of Semic-Rigid Steel Frame with Y-Shaped Eccentric Brace

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Semi-rigid steel frames are used frequently in low-rise and mid-rise buildings located in high seismic areas due to their high ductility and economic solutions. However, there are still some imperfection in this type of structures, such as lower lateral stiffness and larger lateral drift. To mitigate this problem, semi-rigid steel frame with Y-shaped eccentric braces, which is a new type of seismic structural system, can be used as an alternative to perimeter frames. This approach is a useful attempt to explore the ideal seismic system. To the knowledge of the authors, this research is the first series of finite element analysis specifically aimed at studying the seismic performance of semi-rigid steel frame with Y-shaped eccentric braces. Two groups of finite element models of 8-, 12-, 16- and 20-story semi-rigid steel frames, with eccentric braces or no braces, were established in this paper. Cyclic load was applied to each frame using displacement control method. In order to study the hysteretic behavior of semi-rigid steel frames with eccentric braces and compare the seismic performance with that of semi-rigid steel frames with no brace, the load-carrying capacity, stiffness, ductility, and energy dissipation capacity of all models were discussed. The analyses confirm that eccentric brace can increase the lateral stiffness of the semi-rigid steel frame significantly，and reduce the effect of the connection stiffness on the frame stiffness.