中文摘要：

目前,大多数易损性分析方法采用的损伤等级的取值都是确定的,然而,在实际的工程中,结构损伤域的边界不明确,具有一定的模糊性。为此,本文在传统易损性分析的基础上,结合模糊数学与传统可靠度计算方法,考虑模糊准则下的结构易损性。并以一座单塔斜拉桥为例,建立结构的概率地震需求模型,分析考虑模糊准则与不考虑模糊准则2种情况下,4个关键部位的易损性曲线。研究结果表明：在考虑模糊准则与不考虑模糊准则2种情况下的结构的地震易损概率明显不同,因而,有必要在地震风险评估中考虑模糊失效准则的影响。

英文摘要：

At present,the value of different damage levels is costant in most fragility analysis.However,in actu-al projects,the boundary of structural damage domains is actually not explicit,and have the characteristic of fuzziness.Therefore,this paper proposes a fuzzy-stochastic method to analyze seismic vulnerabilities of highway bridges on the basis of traditional fragility theory.The fuzzy-stochastic method combines the fuzzy mathematics and the traditional reliability method.The details of this method are illustrated by taking a single pylon cable-stayed bridge as an example.The probabilistic seismic demand model is established to calculate the probability of bridge components,and fragility curves of four key sections in two different cases of are compared to study the in-fluence of the fuzzy rules on the fragility curves.It is found that the fuzzy rules has a significant influence on structure vulnerabilitis and should be taken into account in the potential earthquakes risk assessment.