Abstract:

The accurate prediction of the tunnel water inflow is helpful in minimizing the tunnel disease, protecting the environment and guiding the design and construction of the tunnel. However, the selection of proper water inflow prediction method, as well as its proper application, is a prerequisite for the accurate prediction of the water inflow. In the paper, the principles and application scopes of various water inflow prediction methods are summarized and analyzed, and the influence of the surrounding rock permeability coefficient, tunnel dimension, groundwater level, grouting ring thickness, grouting effect and lining impermeability grade on the water inflow is analyzed, with Liupanshan tunnel as an example. Furthermore, the limitations and application scopes of the analytical methods are provided, the application of the grouting effect in the water inflow prediction is highlighted, and it is proposed that the impermeability grade of the lining of mountaincrossing highway tunnels should not be inferior to S8.

Key words: tunnel water inflow, groundwater dynamics, grouting, impermeability grade, prediction methods