Research on Spacing Effect of The Construction of Shield Tunnels undercrossed Existing Tunnels at Close Distance

2018 International Conference on Civil and Hydraulic Engineering

土木建筑工程;水利工程

Yang, Fan^1,2 ; Liu, Junyan^1,2 ; Liu, Yan^2 ; Zhang, Liangliang^3

School of Civil Engineering and Architecture, University of Jinan, Jinan

250022, China^1

Eng. Technol. Res. Ctr. for Urban Underground Eng. Supporting and Risk Monitoring of Shandong Prov., Jinan

250022, China^2

China Railway Siyuan Survey and Design Group Co. LTD., Wuhan

430063, China^3

关键词: Additional stress;    Deformation control;    Finite element software;    Shield tunneling;    Stress and displacement fields;    Surrounding environment;    Surrounding soils;    Urban subway networks;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/189/2/022086/pdf
DOI  :  10.1088/1755-1315/189/2/022086

学科分类：土木及结构工程学

来源: IOP

【 摘 要 】

With the increasingly dense distribution of urban subway network, line crossing will inevitably occur. The phenomenon of new tunnels passing through existing tunnels is becoming more and more common. Shield tunneling will inevitably disturb the surrounding soil and redistribute the stress and displacement fields, resulting in the deformation and additional stress of existing subway tunnels. The new tunnel should have strict requirements for the deformation control of existing tunnels and surrounding rocks. The spacing effect of new tunnels under existing tunnels can ensure the safety of new tunnels and the operation safety of existing shield tunnels, which has become an important problem to be solved urgently. On the basis of theoretical analysis, this paper takes a new shield tunnel under the existing tunnel in Xuzhou City as the backing, carries out numerical simulation of the new and old tunnel under different clearance by finite element software, and studies the influence of the new tunnel on the existing tunnel when the tunnel is constructed with different spacing of 1.5m, 0.5D, 1D, 1.5D, 2D and 3D. It is concluded that the reasonable distance between the new tunnel and the existing tunnel should be controlled between 1D and 1.5D under the circumstance of the surrounding environment, the permission of the new tunnel line and the economical and reasonable conditions.