为确保成都轨道交通13号线下穿娇子立交桩基群工程的运营安全，对盾构隧道下穿桥梁桩基群施工安全风险进行评估。首先，采用模糊层次法（FAHP）结合灰色关联度分析法（GRA)进行多层次、多因素安全风险评估，结合实际施工特点从穿越桩基群施工工法、工艺本身出发，建立合理的盾构隧道穿越城市立交桥桩基群施工的安全风险评估指标体系，评选出安全风险影响程度相对较高的因素；然后，将分析结果与现场实测数据进行对比分析，验证安全风险评估的可靠性。结果表明，盾构隧道穿越桥梁桩基群施工过程中，在第1层因素中影响程度最大的是桩基托换施工工艺和盾构下穿施工，在第2层因素中影响程度最大的是原桥墩以及承台与托换梁的衔接。风险评估结果符合工程实际，根据评估结果对桩基托换施工进行重点管控与全过程监控量测，监测结果验证了风险评估方法的适用性和可靠性。

In order to ensure the operational safety of the project of the Chengdu Metro Line 13 crossing the pile foundations of the Jiaozi overpass, the construction safety risks of the shield tunnel crossing the bridge pile foundation group are evaluated. Firstly, the fuzzy analytic hierarchy process (FAHP) combined with grey relational analysis (GRA) is used to conduct a multilevel and multifactor safety risk assessment. Based on the actual construction characteristics and the construction process of crossing pile foundation groups, a reasonable safety risk assessment index system for shield tunnel crossing urban overpass pile foundations is established, and factors with a relatively high degree of safety risk impact are selected. Then, the analysis results are compared with field test data to verify the reliability of the safety risk assessment. Results indicate that during the construction process of shield tunneling crossing bridge pile foundations, the pile foundation replacement construction technology and shield tunneling underpass construction have the greatest impact in the first layer of factors. The original bridge pier and the connection between the bearing platform and the replacement beam have the greatest impact in the second layer of factors. The risk assessment results are in accord with the engineering practice. Based on the assessment results, key control and full process monitoring measurements are implemented for the pile foundation replacement construction. The applicability and reliability of risk assessment method are verified by the monitoring results.