中文摘要：

依托福州地铁1号线盾构隧道下穿既有轨道工程实例,建立造成轨道变形的主要风险因素的故障树模型.通过运用故障树分析方法对轨道变形的风险进行定量分析,得出轨道变形事故的发生概率及故障树底事件的重要度.并在评估底事件发生概率的模糊性上采用专家判断法结合模糊集理论的方法.该方法为地铁盾构隧道下穿既有轨道的风险控制提供参考.

英文摘要：

This paper establishes a fault tree model of the main risk factors causing track deformation based on engineering example of the Fuzhou Metro Line 1 of which the shield tunnel traversing under the existing track. By using fuzzy fault tree analysis method, the track deformation risk is analyzed quantitatively. And then the probability of the track deformation accident and the importance degree of fault tree＇ s bottom e- vents is obtained, when evaluating the fuzzy of probability of bottom events by through combining expert judgement method and fuzzy set theories. The method proposed provides reference for risk control of met- ro shield tunnel below through the existine track.