Quantitative evaluation of the constraint effect and stability of tunnel lining support. (June 2021)

• Record Type: Journal Article
• Authors: Chuang, Sun; Dongxu, Chen; Laigui, Wang; Lin, Wu
• Is Part Of: Tunnelling and underground space technology. Volume 112(2021)
• Publication Date: 2021-06
• Subjects: Tunnel engineering -- FLAC3D secondary development -- Rock–support interaction -- Support constraint effect -- Tunnel stability analysis; Tunneling -- Periodicals; Underground construction -- Periodicals; Tunnels -- Periodicals; Underground areas -- Periodicals; 624.193
• DOI: 10.1016/j.tust.2021.103920
• Languages: English
• ISSNs: 0886-7798

Abstract

Highlights: Supporting structure also has restrictions on the surrounding rock. Stress release rate of surrounding rock should be increased in the 2D model. The boundary of 3D model has influence on the support constraint effect. The range of boundary effect is 1.5 times the tunnel span. Rupturable concrete lining units were developed based on FLAC 3D . Abstract: The surrounding rock stress release rate in a two-dimensional (2D) rock tunnel model and boundary problems in a three-dimensional (3D) rock tunnel model are the main factors that affect the results of modeling rock tunnels. We investigated the constraint effect of supporting structures and boundary effects of the 3D model based on the confinement convergence method. A rupturable lining unit was developed using FLAC 3D to study the influence of the constraint effect on the surrounding rock stress release and influence range of the boundary effects. The results show that the 2D model stress release enhances the virtual support force generated by the support constraint effect by 3–5% of the initial rock stress. A comparison of field monitoring and numerical calculations of the Millin tunnel project shows that the 3D model boundary effect is nearly 1.5 times the tunnel span. The rupturable lining unit directly reflects the stress characteristics of concrete lining in practical engineering and provides support for the quantitative evaluation of tunnel engineering stability.