【作者】 成尚锋； 张海燕； 易伟建；

【Author】 Cheng ShangfengZhang Haiyan Yi Weijian (Guangzhou Transportation Investment Co.,Guangzhou 510050,P.R.China;Civil Engineering College,Hunan University,Changsha 410082,P.R.China)

【机构】 广东省交通实业投资公司； 湖南大学土木工程学院；

【摘要】 桥梁结构易损性曲线为其抗震性能评估提供了依据。在不同水平的地震作用下结构的地震需求和抗震能力的分析是建立易损性曲线的关键。本文在对延性需求谱的性质进行探讨之后,利用大量单自由度体系的非线性时程分析结果,对给定结构周期和屈服水平系数条件下的延性需求的概率分布类型进行了假设检验,并回归得到了四类不同场地上延性需求系数的条件均值和条件标准差,进而建立了随机延性需求谱。结合 Pushover 分析,桥梁结构的易损性曲线可以很方便地获得。算例结果证明建议方法简单有效。更多还原

【Abstract】 Fragility curves provide a basis for the evaluation of seismic performance of bridges.The analysis of structural seismic demand and capacity under different seismic level is the key of the construction of fragility curves.In this paper,the characteristic of ductility demand spectra is investigated.Then utilizing the results from nonlinear time history analysis of single-degree-of-freedom systems under four sets of ground motion records,the probability distribution of ductility demands conditional on given normalized strength and natural period is verified. And regression analysis of conditional mean and standard deviation of ductility demand factor of structures on four types of soil sites are performed.Then a procedure for the construction of probabilistic ductility demand spectra are presented.Combined with Pushover analysis,the fragility curves can be constructed easily.The proposed method is proved effective by an example.更多还原