Numerical Simulation Study On Deformation And Stress In Moutain Due To Excavation Of Chongqing Gele Moutain Lightrail Tunnel

In recent years, with the rapid development of the transportation industry, thusthere are more highway tunnels, high-speed railway tunnels and urban traffictunnels.The characteristics of modern tunnel is large sections and long miles,andbecause of long mileage, will also have to bulit in adverse geological structure, if nottaken seriously, in the construction process will cause secondary geological disasters bythe big disturbance of the bad geological body, It will not only influence theconstruction of tunnel, but also produce the secondary geological disasters.On onehand,the economic will loss,on the other hand, natural environment will be destoryed.On the basis of Chongqing lightrail line1Zhongliangshan tunnel data, threedimensional geological model is established by the three dimensional finite elementsoftware Midas/GTS, According to the model of gele moutain,the cases of the tunnelcrossing the anticline structure are simulated.1) Three-dimensional geological model is established in real size by threedimensional finite element software Midas/GTS. Gele mountain Guanyinxia anticlinetectonic geometry model was established to simulate the gele mountain under thecondition of gravity stress of initial ground stress state. According to the result of thesimulation, analyzes the gele mountain Guanyinxia anticline section initial geostressfeatures and the mountain at different surface topography of the in-situ stress.2) Chongqing lightrail line1Zhongliangshan tunnel cross the Guanyinxia anticline,on the basis of three dimensional geological model of Gele mountain, After that,simulate the Zhongliangshan tunnel excavation in Gele mountain geological model, inkey areas, such as the arch core, anticline wing department of the anticline, In thesensitive parts of the geological structure,summarize the deformation of thetunnel,displacement distribution trend of the mountain and the redistribution of stressfield; the result of disturbance area due to excavation in the mountain, damage zone inmountain, and ground deformation caused by tunnel excavation and so on has beenanalyzed, obtained the relevant laws.3) On the basis of three dimensional geological Gele mountain model, by usingdifferent geological structure and lithologic, The simulation of tunnel excavation iscontinued, the purpose is to remove the geological conditions and different lithologyinterference between two reference variables, judge the influence of different lithology in the same geological structure, and investigate the influence of different geologicalstructure in the same lithology. Analysis on lateral quantitative analysis results indifferent geological tectonic situation, compare the hole body deformation of the largestregional distribution, the maximum distribution of stress concentration, shear stressconcentration distribution, plastic zone distribution and spatial distribution of the earth’ssurface and deformation mountain, summarizes changes in the conditions of differentgeological structure; Under the condition of different lithology, compare the holemaximum deformation size and tunnel excavation on the mountain damage area size,summarizes the change rule under the condition of different lithology.4) Above calculation results, the results data are quantitative analyzed to find outthe most sensitive numerical range.