Seepage Evolution Law Of Water Inrush Disaster In Buried Karst Tunnel

The southwest China is facing a golden period of traffic tunnel and hydraulic engineering construction with the steady implementation of the western development strategy in our country,a large number of tunnel will be constructed in karst region and are facing the water bursting geological hazard more and more seriously.In order to research evolution law of water inrush disaster in buried karst tunnel under excavation,I uses homemade visualization tunnel water inrush experiment device,the large tunnel water inrush experiment system and the finite element analysis software COMSOL Multiphysics to do some following works by indoor water bursting test and the excavation water inrush experiment the numerical simulation.(1)Design and produce visualization experiment device which can observe the soil particles start migration rule and water inrush channel forming process during the time of the tunnel water inrush.The change rules of time and indoor water and outdoor water and pore water pressure and earth pressure leaded by tunnel water inrush under different prevention thickness are researched.(2)Use the large tunnel water inrush experiment system to do the physical model experiment of tunnel inrush under excavation.Analyze each measuring point's dynamic evolution rule of pore water pressure under different confined water pressure and different tunnel rock mass.Get the change trend of pore water pressure change rate in tunnel rock mass advancing with time.Study the change rules of the time which is needed by tunnel inrush and the pore water pressure during the tunnel is inrush and the hydraulic gradient.(3)Establish the numerical simulation model whose prevention thickness is decreasing to analyze the change rule of pore water pressure in tunnel rock mass in COMSOL Multiphysics according to the large physical model experiment.Simulation the change rules of pore water pressure of different prevention thickness and pore water pressure level surface in tunnel rock mass under different tunnel rock mass permeability and different confined water pressure.(4)Summarize empirical equation of pore water pressure related to tunnel rock mass permeability and confined water pressure to analyze and match the data according to the research results of physical experiment and numerical simulation.