الفهرس | Only 14 pages are availabe for public view |
Abstract The main goal of this research is to study the effect of stress redistributions around tunnels. The thesis emphasizes on analyzing the increase in the lining straining actions due to surface loads directly above it. The study is carried out using two-dimensional finite element analyses with plane strain conditions. The finite element program PLAXIS V8.2 is used in the simulations as well as CANDE 2007. Different factors affecting the arching action are considered: method of installation, soil-lining relative stiffness and cover to width/diameter ratio. Moreover, the effect of using different elastoplastic constitutive models on predicting the arching action is considered using two models: Mohr-Coulomb and Drucker-Prager |