Influence Analysis of Metro Tunnel Underground Construction on Existing Metro Station and Viaduct Pile Foundation

Abstract

Objective Influence of metro tunnel closely under-passing the existing metro station and viaduct pile foundation is studied. Method Wulidun Station safety line tunnel on Hefei S1 Line closely under-passes the existing Wulidun Station on Metro Line 2. With this project as the background, the finite element software ABAQUS is used to build a three-dimensional model of the whole construction process, and the deformations of station structure and viaduct pile foundation under line by line excavation and simultaneous excavation of the above two lines are compared and analyzed. In order to investigate the applicability of similar engineering under different soil conditions, by changing the two parameters of soil cohesion and elastic modulus, the influence of the two parameters on the settlement of soil and station bottom plate during tunnel excavation are analyzed. Result & Conclusion After the completion of the tunnel excavation, the maximum settlements of the bottom plate of Metro Line 2 Wulidun Station under the two schemes are very similar being 0.73 mm and 0.77 mm, both meeting the requirements of the control standard. When the soil cohesion and elastic modulus are less than 70 kPa and 100 MPa respectively, the settlement of the station structure and the horizontal displacement of the pile foundation during tunnel excavation begin to increase significantly, which should be treated seriously.

Keywords

• metro tunnel
• existing station
• underpass construction
• cohesion
• elastic modulus