Time-dependent tunnel deformations in homogeneous and heterogeneous weak rock formations. (December 2017)

• Record Type: Journal Article
• Authors: Sainoki, Atsushi; Tabata, Shingo; Mitri, Hani S.; Fukuda, Daisuke; Kodama, Jun-ichi
• Is Part Of: Computers and geotechnics. Volume 92(2017)
• Page Start: 186
• Page End: 200
• Publication Date: 2017-12
• Subjects: Time-dependent tunnel deformation -- Numerical analysis -- Weak rock formation -- Tertiary creep; Engineering geology -- Data processing -- Periodicals; Soil mechanics -- Data processing -- Periodicals; Rock mechanics -- Data processing -- Periodicals; 624.1510285
• DOI: 10.1016/j.compgeo.2017.08.008
• Languages: English
• ISSNs: 0266-352X

Abstract

Abstract: To investigate long-term, time-dependent tunnel deformations, this study employs a non-linear rheological model capable of considering the tertiary creep behaviour of the rock mass (Okubo and Fukui, 2006). A model parametric study is undertaken with a 3D numerical model encompassing a tunnel. The results show that the tunnel walls start to deform at an accelerating rate after a lapse of ten years. The results offer an explanation to previously reported tunnel instability cases. A 3D numerical model encompassing weak rock formation obliquely intersecting with the tunnel is then constructed. The analysis yields asymmetric wall deformation pattern, suggesting the need for optimizing rock supports.