Modal analysis of subway tunnel in soft soil during operation

作     者：Ling Wan Xiongyao Xie Lujun Wang Pan Li Qiang Huang 

作者机构：College of Civil Engineering and ArchitectureNanchang Hangkong UniversityNanchang 330063China Jiangxi Transportation Institute CoLtdNanchang 330200China Key Laboratory of Geotechnical and Underground EngineeringMinistry of EducationTongji UniversityShanghai 20092China Center for Hypergravity Experimental and Interdisciplinary ResearchMOE Key Laboratory of Soft Soils and Geoenvironmental EngineeringCollege of Civil Engineering and ArchitectureZhejiang UniversityHangzhou 310058China Institute of Geotechnical EngineeringNingbo UniversityNingbo 315211China 

出 版 物：《Underground Space》 (地下空间（英文）)

年 卷 期：2023年第8卷第1期

页      面：181-195页

核心收录：

学科分类：08[工学] 0818[工学-地质资源与地质工程] 0814[工学-土木工程] 0701[理学-数学] 0801[工学-力学（可授工学、理学学位）] 0823[工学-交通运输工程] 0812[工学-计算机科学与技术（可授工学、理学学位）] 

基　　金：supported by National Key R&D Program of China(Grant No.2019YFC0605103) National Natural Science Foundation of China(Grant Nos.51978431,52008214) Science and Technology Foundation of Jiangxi Provincial Transportation Department(Grant No.2020Z0003),China. 

主　　题：Monitoring method Modal identification Vibration response Operational subway tunnel 

摘      要：Modal parameters are of great significance in civil engineering because they can characterize the properties of structures and be used for vibration control and structural health monitoring.Subway tunnels are long linear truss structures combined with the mutual cou-pling of the surrounding soil.Therefore,the operational modal analysis of a mutual coupling tunnel is complicate,as is the modal iden-tification of shield tunnels in a time–frequency domain,and these are hot civil engineering topics.Using the shield tunnel of Shanghai metro line No.12 project as a case study,we carried out the vibration response monitoring of a subway tunnel during operation and presented methods to identify structural modal parameters.The modal parameters of lower vibration modes were estimated using response measurements.Modal frequencies and shapes were identified with high precision and accuracy using the orthogonal polynomial clustering algorithm under hammer excitation conditions and the autoregressive-moving-average model under ambient excitation con-ditions.The dynamic behavior of a mutual coupling tunnel presented obvious low frequency characteristics,and the first 9th order mode frequencies were less than 100 Hz.The diagonal values of the modal assurance criteria were all greater than 0.85.The modal parameters can be used for the health monitoring of operational subway tunnels.