Influence of excavation of super deep foundation piton deformation of adjacent metro tunnel(PDF)
长安大学学报（自然科学版）[ISSN:1006-6977/CN:61-1281/TN]
- Issue:
- 2020年6期
- Page:
- 77-85
- Research Field:
- 桥梁与隧道工程
- Publishing date:
Info
- Title:
- Influence of excavation of super deep foundation piton deformation of adjacent metro tunnel
- Author(s):
- WANG Lijun1; QIU Junjun2; HE Zhongming2; LUO Xin1; HUANG Zili2
- （1. Guangzhou Metro Group Co. Ltd, Guangzhou 510380, Guangdong, China; 2. School of Traffic andTransportation Engineering, Changsha University of Science and Technology, Changsha 410114, Hunan, China）
- Keywords:
- tunnel engineering; super deep foundation pit; numerical simulation; metro tunnel; horizontal displacement
- PACS:
- -
- DOI:
- -
- Abstract:
- In order to study the influence of the excavation of an super deep foundation pit on the deformation of the adjacent metro tunnel, based on the actual project profile, a threedimensional model was established using the finite difference software FLAC3D. In the process of foundation pit excavation, the surface settlement of the adjacent metro tunnel, the deformation of the diaphragm wall of the retaining structure and the overall deformation of the metro tunnel were studied, and the influence of the relative position of the foundation pit and the adjacent metro tunnel on the lateral displacement of the metro tunnel was analyzed. The results show that under the action of excavation of foundation pit, three settlement grooves are appeared on the outer surface of the pit adjacent to the subway tunnel due to the influence of the metro tunnel. The maximum ground settlement value appear in the first groove, and gradually moved to the right as the excavation depth increase, the second groove gradually disappear, and the third groove gradually formed but it is not obvious. The maximum settlement value is 10% larger than that without the influence of the metro tunnel. With the increase of excavation depth, the lateral displacement curve changes from cantilever shape to parabola shape, which is similar to the middle and two small ends. There is no kick shape curve. The internal support can effectively limit the large lateral deformation of the diaphragm wall and ensure the relative stability of the foundation pit. The displacement of the metro tunnel is symmetrical, its horizontal displacement is inverted, which is mainly horizontal displacement, while its vertical displacement is small. When the distance between the metro tunnel and the diaphragm wall is less than 20 m, the influence on the subway tunnel is significant, which is the main influence area. With the increase of buried depth, the maximum lateral displacement of the metro tunnel increases first and then decreases. The growth trend is similar to the lateral movement of the diaphragm wall without the metro tunnel. The interaction of the subway tunnelsoildiaphragm wall connection wall is complex, which is significantly affected by the relative position of the subway tunnel and the diaphragm wall. 2 tabs, 11 figs, 25 refs.
Last Update: 2020-12-17