Study On Variation Characteristics Of Tunnel Seepage Field Based On Displacement

China has a great amount of people.In order to thoroughly achieve the goal of common prosperity in socialism and to complete the fast and good circulation of trade across the country,it is extremely necessary to strengthen highway construction.For mountainous areas,tunnels will become more common.Also,the depth and length of the tunnel will continue to increase,All kinds of geological disasters may occur in the process of tunnel excavation.The hazard of water inrush in fault fracture zone is one of the most important hazards in mountain tunnels,especially deep and long tunnels.The risk of water inrush during tunnel excavation and later operation can be greatly reduced by drainage ahead of time and drainage of lining.The impact of different drainage on the project and the environment is different.This paper is based on the analysis of the engineering properties of the fault fracture zone and related examples of water inrush.Then based on model experiment,theoretical calculations and numerical simulations to study the characteristics of the seepage field under different drainage in the fault fracture zone.The main research contents and conclusions are as follows:1.Through physical model experiment,the relationship between water supplement and drainage conditions and groundwater level and groundwater pressure was studied.The test shows that the change of groundwater level is different under different recharge and drainage conditions.There are different forms of groundwater level,such as incomplete falling funnel shape and complete falling funnel shape Under different drainage conditions,the water pressure reduction coefficient will have certain changes in the drainage process.2.On the basis of model experiment,the dissertation established a theoretical calculation model to verify and improve the test results using theoretical calculation methods.The rationality of the experiment model is verified by the theoretical calculation.At the same time,the correlation between the reduction coefficient,the displacement,permeability coefficient and groundwater level is also obtained.3.The numerical simulation method is used to examine the results of the model experiment.The influence of groundwater level,drainage and other factors on the groundwater seepage field was studied.Based on the coupling of stress and seepage,the effect of seepage field under different seepage flow and total head on the stress field and displacement field of fault fracture zone is analyzed.The best water discharge and protection measures under the test conditions are obtained.Including heaped load the foot part of the tunnel face during drainage construction,appropriately strengthening the design of the waist wall during lining drainage in later stage,etc.which can provide reference for similar tunnel construction.