Study On Drainage Of Groundwater In A Vertical Fault To A Deep Buried Tunnel

This dissertation researches on the factors which affect the drainage of groundwater in a vertical fault to a deep buried tunnel by building ideal models. According to the field data, the ideal models have been calibrated. Thus, these researches provide convincing coefficients for solving the drainage of the tunnel.The first model considers the fractured media and supposes that the two sides of fault zone do not permeate water into the fault zone. It considers constant drawdown in the point of tunnel and unsteady flow. It also considers that permeability and specific storage decreases with the depth increasing. In order to extrude the factor of depth, this part uses the dimensionless equation. This equation is solved using the Visual Basic based on the Galerkin Finite Element method. This solution was compared with the semi-analytical solution and was good agreement with the semi-analytical solution.The second model considers the fractured media in the fault but porous media in the two sides of the fault, and also supposes two sides of the fault zone permeate water into the fault. It also considers the permeability and specific storage decreases with the depth increasing in the fault It used the groundwater software called Processing Modflow to simulate the model and is compared with the solution above.Finally, by combining the field concentrated drainage of auxiliary tunnel called BK2+633, this dissertation calibrates the models above and provides the convincing coefficients for dealing with the problem of large amount of drainage.