Analysis of influence of asynchronous excavation of twin tunnel on ground surface settlement in clayey fine soils

Document Type : Original Article

Authors

1 Geotechnical Group, Garmsar Campus, Amirkabir University of Technology, Tehran, Iran

2 Department of Civil Engineering, Shahid Rajaee Teacher Training University,Tehran, Iran

Abstract

With expanding of cities and restriction of usable urban areas, development of underground structures through asynchronous construction of twin tunnel or new tunnel excavation near existing tunnel is on the rise. Therefore, predicting the amount of ground settlement resulting from asynchronous excavation of twin tunnel to prevent damage to the building foundations or sensitive structures is one of the most important issues that must be considered before starting of excavation. One of the most effective factors for the maximum surface settlement resulting from asynchronous excavation of twin tunnel is the geo-mechanical properties of the soil mass, dimensions and geometrical arrangement of the tunnels, which has a large impact on the maximum amount of ground settlement and the shape of the displacements curves. In this paper, a number of numerical analysis using ABAQUS finite element software is performed to investigate the surface settlement resulting from asynchronous excavation of twin tunnel, and the effect of three parameters of tunnel diameter, center-to-center distance of the tunnels and the depth of the tunnels are discussed in detail in this paper. Numerical modeling validated with a centrifuge tests of asynchronous excavation, which were performed by the University of London with accuracy of 94.22%, 98.71% and 99.56%, respectively.

Keywords


Volume 23, Issue 62
Spring 1400
June 2021
Pages 5-11
  • Receive Date: 21 January 2020
  • Revise Date: 12 May 2021
  • Accept Date: 13 November 2021