Research On Deformation Rules Of Big Section And Shallow Cover Soil Tunnel Surrounding Rocks

With the rapid development of the Chinese economy,urbanization process will also further accelerate,more and more rural population enter the cities,which will certainly bring increasing pressure on cities.So,many cities are trying to find the way of local traffic,subways and highways around cities are generated.This article is based on a city highway beltway construction of a tunnel as the background,the use of NATM tunnel project monitoring measurement theory, choose to monitor a typical cross-section,focus on the process of excavation and support of the soil surrounding the tunnel deformation the impact of the situation. Specific studies are as follows:(1) during the tunnel construction,the auther uses many means of monitor to the rock monitoring above the tunnel in detail,including the convergence of level,the subsidence of dome,the subsidence of surface and the deep displacement of surrounding rock and so on,to get a lot of valuable data,and have applied them in the research of this article.(2) Making use of the levelnal convergence and the subsidence vault of dome in the monitoring to make the return of a logarit function and exponential function,so as to get the result that through the using of exponential function of these two parts to go on prediction of deformation is feasible.(3) Making two-dimensional finite element analysis in the different methods of tunnel constructing,obtained that the most suitable type of tunnel construction are the method CRD by comparing the results of the analysis(4) The article also through making three-dimensional finite element simulation on the full-face excavating method,get the progress of the dome subsidence,ground subsidence,the case of displacement of the tunnel cross-section of different positions levelnal convergence and different positions along the deepth of surrounding rocks.