Research On Surrounding Rock Control And Construction Technique Of Laoshi Moutain Tunnel

Along with the development of the construction of the railway, highway and municipal tunnel, large section tunnel is increasing also, large cross section tunnel surrounding rock control and the excavation method of more and more, and become more mature. YunGui Laoshishan mountain railway tunnel inlet side and clay widely distributed, and poor stability of surrounding rock, the basic of self stabilizing ability. Into comprehensive consideration, choose seven steps excavation steps, the method is widely applied in our country, but some field test is not much, for this method construction process, especially the excavation division phase stress and deformation characteristics of surrounding rock and supporting structure should be further in-depth understanding of, the main content of the study are as follows:The main contents of the research are as follows:analysis the influence factors of influence the stability of tunnel surrounding rock, the old stone mountain tunnel geological evaluation on the stability of surrounding rock, stone mountain old stability classification of surrounding rock is determined. The FLAC3D is adopted to surrounding rock excavation are numerically simulated under different supporting conditions, specific analysis of bolting and shotcrete support, under the condition of bolting and shotcrete+bolt support tunnel surrounding rock deformation, stress and displacement were analyzed, and the choice of supporting schemes and supporting parts need to be improved. Finally, in the excavation of tunnel surrounding rock stability and the tunnel construction based on the study of the mechanics, puts forward the old stone mountain tunnel construction technology scheme of the tunnel, and points out matters of attention in the construction, which provides theoretical basis for the safety of the tunnel construction, to ensure the smooth progress of construction.