Investigation of the cause of shield-driven tunnel instability in soil with a soft upper layer and hard lower layer
Investigation of the cause of shield-driven tunnel instability in soil with a soft upper layer and hard lower layer
复制标题
上软下硬土中盾构隧道失稳原因探讨
DOI：
10.1016/j.engfailanal.2020.104832
复制
发表时间：
2020-12-01
影响因子：
4
通讯作者：
Feng, Tugen
中科院分区：
文献类型：
--
作者：
Zhang, Jian;Liang, Yu;Feng, Tugen
This paper presents a limit analysis of a tunnel in non-homogeneous soil using the upper-bound limit analysis in combination with finite element technology and a mesh adaptive strategy by investigating the critical loads and failure mechanisms of a tunnel cross-section and tunnel face. A case study of an underground tunnel in China is conducted, with a focus on the effects of multiple soil layers and different soft soil parameters. This work demonstrates that the variation in the soil layering plays an important role in the initiation of tunnel collapse, possibly shifting the failure region and even changing the failure mechanism. When the soil changes from a strongly weathered conglomerate to a soft soil, not increasing the low tunnel pressure quickly enough and using the wrong excavation mode are the two main reasons for tunnel instability and large surface settlement.
