Analytical Solution for the Steady-State Karst Water Inflow into a Tunnel

Table 1

Characteristic data for verification.

Characteristic	Value
The pressure head of the cavern	54 m
The radius of the tunnel	7.25 m
The radius of the cavern	4 m
The radius of the grouting circle	2.25 m
The initial support radius	2 m
Permeability coefficient of surrounding rocks	cm·s^-1
Permeability coefficient of grouting circle	10^-7 cm·s^-1
Permeability coefficient of initial support	10^-8 cm·s^-1