Study On Stability Of The Surrounding Rock And Supporting The Deep-buried Tunnel

The excavation of the deep-buried tunnels makes the stress of the surrounding rock release and re-distribution, Surrounding rock mass and the supporting structure of mechanical properties occur complex changes, it will cause damage to large deformation and plasticity.So research deep-buried tunnel stability and the mechanical characteristics all have significance not only in the development of the disciplines but also in underground space for the effective and rational development, optimization and construction to ensure the smooth conduct of the project.This paper depends on deep-buried tunnel(Jiahuoyan Tunnel),through measured information at construction field, combined the finite difference software FLAC3D numerical simulation,study on the dynamic construction mechanics feature of intersection part of deep buried tunnel. Through comparative analysis the measured data and simulation results,to probe the deep-lying tunnel mechanism of rock deformation and failure.Elaborate the finite difference method on underground engineering simulation of the basic principles of the construction process. The process of tunnel excavation on the finite-difference simulation of three-dimensional numerical, Concluded that: the process of tunnel boring bolt force curve; Both sides of the tunnel working face and the driving range in front of 10-20m appear pressure stress concentration zone, lumbar arch and arch foot appear shear stress concentration zone, in the vault and floor damage to the main tension, waist and foot arch arch to the main shear failure; dome surrounding the sinking and displacement as the tunneling rate of displacement decreases; when driving to 25m, surrounding rock displacement curve gradually stabilized; deep-buried tunnel in the early commitment to support more than 90% of the rock pressure, secondary lining as a safety reserve; determine the best supporting time of defferent sections of the secondary lining. The tunnel folder monitoring data show that:in the design of its support conditions, the dome surrounding the sinking and displacement all in the scope of deformation reserved. content with the design specifications.Combination of monitoring and measuring the results of numerical simulation analysis, propose failure mechanism of rock deformation and deformation characteristics of Jiahuoyan tunnel.analysis of the tunnel roof and side-wall of concrete falling off of the main reasons for the phenomenon and solutions.More in-depth exploration of the deep tunnel of the deformation and damage mechanisms, provide the basis and practical experience for the oretical studies of deep-lying tunnels ,optimize the design and construction.