RC框架结构基于性能的优化分析

Performance-based Optimization Analysis on RC Frames

对某实际工程中按工程设计软件PKPM设计的一榀框架(KJ-1)进行优化分析,以达到降低工程材料用量,满足经济要求的目的.采用有限元软件SAP2000对KJ-1进行Pushover分析,得到KJ-1的性能点及KJ-1在性能点时的层间位移角值;将层间位移角值与规范层间位移角限值及相应的性能要求进行比较,KJ-1满足抗震性能目标1的要求.根据实际工程中要求,KJ-1满足性能目标3的要求即可;对KJ-1进行优化(满足我国现行抗震设计规范),再进行Pushover分析,评价优化后的KJ-1的抗震性能.通过两次优化分析,使KJ-1在满足抗震性能目标要求3的情况下,钢筋和混凝土用量较优化之前分别降低了41.7%和24.1%.结果表明,基于性能的优化设计可以保证结构在满足地震作用下的性能目标的前提下,更经济合理.

The optimization analysis of a frame（named by KJ-1）in an practical engineering designed by engineeringdesign software PKPM was conducted in order to meet the requirements of economy by reducing the amount of usedengineering materials. Pushover analysis on KJ-1 was performed by using the finite element software SAP2000. As aresult,the performance points of KJ-1 were obtained,as well as the inter-layer displacement angle value at performancepoints. A comparison between the obtained inter-layer displacement angle of KJ-1 and the displacement angle limitin the standard as well as the corresponding performance requirements indicated that KJ-1 met the target 1 of seismicperformance requirements. According to the actual engineering requirements,KJ-1 just needed to meet the requirementsof the target 3 of performance requirements. Thus optimization analysis of KJ-1（which met the current seismic designcode in our country）was performed,and then Pushover analysis on the optimized KJ-1 was conducted to evaluate theseismic performance of the optimized KJ-1. By being optimized twice,the amounts of reinforcement and concrete werereduced by 41.7% and 24.1% in the case of meeting the target 3 of seismic performance requirements,respectively.The results showed that the performance-based optimization design could ensure a structure more economical andreasonable,on the condition that the structure satisfied the targets of the seismic performance requirement.