地面堆载对地铁盾构隧道变形影响规律研究

Study on Influence of Ground Surcharge on Deformation of Subway Shield Tunnel

文章以上海某地铁区间段施工前堆土的盾构隧道为工程背景,对隧道收敛变形的现场监测数据进行分析,并建立数值计算模型对从隧道施工前的堆载到施工完成后的卸载全过程进行模拟。结果表明:隧道施工前的地面堆载对隧道变形具有显著影响,隧道线开挖的先后顺序也会对隧道变形造成影响;采用弹簧单元模拟管片连接,能够更加真实地反映隧道管片受力变形特点,与实测结果较为相符。

Based on the shield tunnel with ground-surcharge before construction of a subway section in Shanghai,the field monitoring data of the tunnel convergence deformation are analyzed,and the numerical model is established to simulate the whole process from overloading before construction to unloading after construction.The results show that the ground-surcharge before the tunnel construction has significant influence on tunnel deformation,and the sequence of the tunnel excavation will also affect the deformation of the tunnel.The spring element,which is used to simulate the segment connection,can reflect the stress and deformation characteristics of tunnel segments more realistically,and it is more consistent with the measured results.