Optimal Design Of Residential Steel Structure Based On Performance-Based Seismic Design (PBSD)

The performance-based seismic design method is a prevailing research topic in the 21st century, whose philosophy is to ensure the function of buildings to meet the requirements of users and society in different intensity of earthquakes. In this paper, we studied the implement method of performance-based seismic design, and Combined this the method to develop high-rise residential steel structure optimization software using the ANSYS finite element analysis software, Its purpose is to make the structure satisfy different seismic performance goals and obtain the optimal section size of components, thereby, we could achieve the goal to minimize the amount of the steel structure.This paper will organically combine the performance-based seismic design and structure optimization design. According to performance-based seismic design, the performance levels and performance goals and earthquake levels of seismic design will be studied. By comparing the two types of performance-based seismic design methods combined with the "Code for Seismic Design of Buildings"(GB50011-2010), exercisable method of performance-based seismic design of residential steel structure is proposed. According to the optimization design of residential steel structure, the optimization method combined with the optimization module of ANSYS (zero order method and the first order method) was studied. Based on the statistics of beam and column distribution of residential steel structure, efficient optimization scheme of the whole structural modeling analysis and two kinds of maximum number of steel beam optimization was established. Using the APDL scripting language in ANSYS software, according to performance-based seismic design method and constraints of the deformation, internal force, structural requirements of composite beam in the current specification, the program was developed for optimization design of residential steel structure.Through optimized example of 24-story residential steel structure, we compared the structure optimization results based on three kinds of performance goals, the original steel consumption of 24-story residential steel structure is 520.05t, thereinto, two types steel consumption of the largest amount of steel beam is 184.45t. Optimization results show that:for performance goal 1 (intact residential steel structure under frequent earthquake), the steel consumption of the two types of steel beam is 161.32t, compared with the original design, the optimized steel consumption of the two types of steel beam be saved 23.13t, the proportion of optimization is 12.54%. For performance goal 2 (intact residential steel structure under moderate earthquake), the steel consumption of two types of steel beam is 181.77t, compared with performance goal 1, the steel consumption added 20.45t, the proportion of raise is 12.54%; for performance goal 3 (intact residential steel structure under rare earthquake), the steel consumption of two types of steel beam is 208.69t, compared with performance goal 1, the steel consumption added 47.37t, the proportion of Raise is 29.36%.The results show that:we have optimized the section of structure according to three performance goals of residential steel structure by using PBSD. The owner according to the steel weight of structure that meet the three different performance goals to choose suitable and acceptable performance goal, the designer of residential steel structure according to the specific performance goal to carry out optimization design. The optimization program has good portability and universality mentioned in this paper, which could be used to optimize other structure like this for engineers and technicians, In this paper, we have explored the method of performance-based seismic design actively, The optimization program has a great significance for promote the popularity of residential steel structure.