Effect of Spatial Variability of the Elastic Modulus in Composite Ground on the Structural Performance of Large-diameter Tunnels. Issue 7 (October 2021)

• Record Type: Journal Article
• Authors: Zhang, D M; Chu, W; Huang, Z K; Li, B J; Zhang, L; Zhong, Y
• Is Part Of: IOP conference series. Volume 861:Issue 7(2021)
• Publication Date: 2021-10
• Subjects: Earth sciences -- Periodicals; Environmental sciences -- Congresses; Environmental sciences -- Periodicals; 550.5
• DOI: 10.1088/1755-1315/861/7/072010
• Languages: English
• ISSNs: 1755-1307

Abstract

Abstract: The spatial variability of soil properties is often neglected in design and construction, resulting in underestimating or overestimating the tunnel structural performance. Furthermore, the risks of ignoring the spatial variability of ground properties increase significantly as the tunnel diameter increases. This study investigates the effects of ground spatial variability on the convergence of shield tunnels in the composite ground, based on a real case of a cross-sea tunnel typically embedded in a ground mixture of soft clay and hard rock in Shenzhen, China. The influence of scale of fluctuation (SOF) for the soil and rock elastic modulus on tunnel convergence is investigated. It is found that the mean value of the tunnel convergence is less affected. In contrast, the tunnel convergence coefficient of variation is strongly affected by changing the elastic modulus SOF of the soil or rock layer. Moreover, the results indicate that as the elastic modulus follows the lognormal distribution, the vertical and horizontal convergence of the tunnel agrees well with the lognormal distribution.