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Tunnel excavation may result in the failure of an adjacent completed tunnel.Interactions of adjacent tunnels play an important role on the stability of tunnel-support. This thesis aims to investigate the interaction between adjacent multiple tunnels. First, the thesis proposes a methodology for feed- basced analysis of rock tunnels. The methodology, then, is applied on studying the problems of multiple-tunnel interaction. These problems include(1)the difference between single-tunnel analysis and multiple-tunnel analysis; (2) the influence of tunnel-spacing; (3) the influence of excavation sequence of multiple tunnels. The results of numerical simulations reveal several findings. The excavation of adjacent tunnel(s) may result in the deformation and support-stresschange of a completed tunnel. By increasing the tunnel spacing, the interaction between adjacent multiple tunnels is reduced;both the changes in defor-maion and support-stress due to adjacent tunnel-construction will decrease. The sequence of tunnel- excavation also affects the interaction between adjacent multiple tunnels. In conclusion, the interaction between multiple tunnels is important, and should not be ignored in the design of the support of multiple tunnels.
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