Analysis Of Coupled Seepage Fields And Stress Fields In Highway Tunnel

Tunnel flooding is the common main geological disaster in the tunnel construction, also is the main disease in operation. In deeply buried tunnel, geology condition is complex. Many hydrogeological units are opened out. Tunnel excavating, causes stress heavy distribution of rock mass in tunnel. Meanwhile destroyed the ground-water drainage channel, intensified the ground- water transformation function to fractured rock mass. Therefore,it is extremely significance to research the coupled seepage /stress fields about tunnel region to project safety.Although the people gradually realized the importance of coupled seepage/ stress fields, the present experimental study and the theory method is immature. Considered the research of coupled seepage /stress in fractured rock mass is an extremely complex topic. This topic has already acquired many results at present, but as a result of the question's complexity, it is still incomplete. Especially applied research to disturbed rock in the actual project was not very perfect. In this article, in view of this aspect situation, combining with the concrete highway tunnel project to outspread a series of correlations work.In this article, the research object is Li Jiahe tunnel on Xi'an-Hefei highway, links the field observation, the field test, the fundamental research, the simulation analysis base on GEO-SLOPE and other many kinds of methods to conduct variously research of the hydraulic parameters of rock mass, coupled computation model of seepage/ stress fields, the coupled and uncoupled function etc. under the condition of highway tunnel excavation. Obtained some guiding conclusion to the actual project. In this paper, results of research mainly are following:(1) Through the analysis, we can obtained that forecast of flooding in tunnel excavation, must consider coupled function of seepage / stress fields.(2) In this article, the influence of the stress field to the seepage field mainly is which excavation causes stress heavy distribution of rock mass adjacent tunnel, leading the new crevasse to produce, the original crevasse closed or expansion, thus changed the penetrating quality of rock mass, causes the seepage quantity change. The influence of Seepage field to stress field only to occur in radius 6 time scopes of the tunnel, the reason is the excavation influence scope is only 6 times radius of tunnels. Therefore only in this scope, the hydraulic conductivity has been changed.(3) Considered coupled seepage / fields, is playing the vital role to the project security. Considered the coupled function, the flow flux of the reservoir to the tunnel is bigger compares to the uncoupled. This is helpful to correctly estimate the problem of tunnel flooding in the course of tunnel excavation.(4) Through the numerical simulation analysis, which can provide the better design basis for the excavation design of Li Jiahe highway tunnel in future, favored in the better solution of the draining water question in tunnel excavation process.(5) According to the computed result of seepage quantity of the tunnel, this paper proposed the corresponding project measure.