In-situ Monitoring Analyses of the Influences of Deep Foundation Pit Excavation on Adjacent Metro Tunnels and Surrounding Strata
(1 School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai 200093; 2 Key Laboratory of Geohazard Prevention of Hilly Mountains, Ministry of Land and Resources, Fuzhou 350002; 3 East China Architecture Design and Research Institute Co. Ltd., Shanghai 200002)
Abstract��
The operating tunnel deformation and soil mass settlement induced by deep foundation pit excavation are highly concerning in urban rail transit construction safety management and risk assessment. Based on the Shanghai Symphony Orchestra foundation pit project and the monitoring data for the operating tunnel and enclosure structures, the rules and characteristics of surrounding ground settlements, diaphragm wall deformations, horizontal convergence and vertical displacements of the foundation pit at different construction stages are analyzed. The measured results show that the overall trend of ground settlements is one of sinking and is generally presented in a parabolic distribution; the lateral deformations of the soil mass and diaphragm walls present substantially the same variation, which moves towards the inside of the foundation pit, and the influence of excavation depth on the horizontal displacements is not a simple linear relationship; horizontal additional convergence is presented by stretching outward, and the convergence increases with the excavation of the foundation pit; and the SMW reinforcement for both sides of the diaphragm wall can effectively control the deformation of the tunnel, the surface outside of the foundation pit and the diaphragm walls.
.In-situ Monitoring Analyses of the Influences of Deep Foundation Pit Excavation on Adjacent Metro Tunnels and Surrounding Strata[J] MODERN TUNNELLING TECHNOLOGY, 2017,V54(2): 177-184
2017, Vol. 54 