Optimized Design Of Ebsf Used In-High-Rise Buildings

Eccentrically braced steel frame(EBSF) used in high-rise buildings is a new structural anti-seismic system which is developed in recent years. It performs excellent energy-consuming ability when bearing unwonted earthquake. To make EBSF meet needs of "three-level" in the anti-seismic system and meet all functions; to make the steel volume least and reduce structure cost. Firstly, this paper focuses on the research and theory of anti-seismic parameters of EBSF and active beam link, establish rational mechanism and yielding model of the structure, set forth the design principle and method of it. Then, using the method of optimal design, a computer-based method is presented for optimal design of EBSF used in high-rise buildings.Concerned the discrete area of the steel shape, a method is presented: searching the best solution of continual variable first by criteria ,and next searching optimal solution by direct-searching method of mixed variable on the original point of the continual result. The motive is to make the steel volume least, reduce structure cost. Member sizes may be chosen form discrete aggregate. The principal idea is to search the discrete optimal solution on the base of the continual optimal solution under meeting every restrict condition.Program designed with C++ language is used to conduct the optimal process and two numerical examples are calculated using the program. The results show that the number of iteration is small and the convergence process is also stable. The show also the method is suitable to EBSF used in high-rise building. Furthermore, the flexibility of this method may make it apply in other structures.