Research on influence mechanism analysis and numerical simulation of foundation pit excavation on existing underground tunnels
XU Yaqiang
ZHANG Zhibiao
TIAN Peng
CHEN Siyu
Abstract：The excavation of deep foundation pit will produce unloading effect,which will have an adverse effect on the adjacent existing tunnels.In order to explore the influence of foundation pit excavation on tunnel stress deformation,this paper selects a foundation pit project located directly above the subway,and uses large-scale finite element software to simulate and analyze the foundation pit excavation process and its possible impact.The model uses the Moore Coulomb constitutive relationship to describe the mechanical properties of the soil,uses the diaphragm wall to simulate the supporting structure of the foundation pit,and the friction contact conditions are set between the diaphragm wall and the soil,and the excavation process of the foundation pit is simulated by removing the life and death elements,and the stress and displacement changes of the tunnel and the foundation pit when the excavation depth h and the distance between the bottom of the diaphragm wall and the top of the tunnel l are considered.
Keywords：foundation pit excavationtunnelfinite element analysisvertical deformation
Publication Date：2025-04-25
Pages：4( 14-17 )