Parametric study on collapse margin ratio of structure  

作　　者：欧晓英 何政 欧进萍 

机构地区：[1]Department of Civil Engineering,Dalian University of Technology

出　　处：《Journal of Central South University》2014年第6期2477-2486,共10页中南大学学报（英文版）

基　　金：Projects(51161120359,90915005)supported by the National Natural Science Foundation of China;Project(NCET-08-0096)supported by the Program for New Century Excellent Talents in University of the Ministry of China

摘　　要：The determination of collapse margin ratio(CMR)of structure is influenced by many uncertain factors.Some factors that can affect the calculation of CMR,e.g.,the elongation of the structural fundamental period prior to collapse,the determination of earthquake intensity measure,the seismic hazard probability,and the difference of the spectral shapes between the median spectrum of the ground motions and the design spectrum,were discussed.Considering the elongation of the structural fundamental period,the intensity measure Sa(T1)should be replaced with *aS in the calculation of CMR for short-period and medium-period structures.The reasonable intensity measure should be determined by the correlation analysis between the earthquake intensity measure and the damage index of the structure.Otherwise,CMR should be adjusted according to the seismic hazard probability and the difference in the spectral shapes.For important long-period structures,CMR should be determined by the special site spectrum.The results indicate that both Sa(T1)and spectrum intensity(SI)could be used as intensity measures in the calculation of CMR for medium-period structures,but SI would be a better choice for long-period structures.Moreover,an adjusted CMR that reflects the actual seismic collapse safety of structures is provided.The determination of collapse margin ratio （CMR） of structure is influenced by many uncertain factors. Some factors that can affect the calculation ofCMR, e.g., the elongation of the structural fundamental period prior to collapse, the determination of earthquake intensity measure, the seismic hazard probability, and the difference of the spectral shapes between the median spectrum of the ground motions and the design spectrum, were discussed. Considering the elongation of the structural fundamental period, the intensity measureSa（T1） should be replaced with＊aS in the calculation of CMR for short-period and medium-period structures. The reasonable intensity measure should be determined by the correlation analysis between the earthquake intensity measure and the damage index of the structure. Otherwise, CMR should be adjusted according to the seismic hazard probability and the difference in the spectral shapes. For important long-period structures, CMR should be determined by the special site spectrum. The results indicate that bothSa（T1） and spectrum intensity （SI） could be used as intensity measures in the calculation of CMR for medium-period structures, but SI would be a better choice for long-period structures. Moreover, an adjusted CMR that reflects the actual seismic collapse safety of structures is provided.

关 键 词：collapse margin ratio strong ground motion intensity measurement probability of exceedance Housner＇s spectrum intensity spectrum acceleration 

分 类 号：TU312[建筑科学—结构工程] TU311.3