PREDICTION OF GUSHING WATER IN CIMU TUNNEL

The hydrogeological investigations finding that the loose accumulation horizon pore water,weathering fissure water in bedrock and clastic rock fissure water is the major source of gushing.in order to obtain the permeability coefficient of rock mass,in-site tests such as Pumping test,water injection test and water pressure test have been performed.the construction period inflow has been estimated by runoff modulus method,air precipitation supplies method and dewatering method.The patterns of gushing in different strata also been ascertain.it is recommended that The water plugging measure based on shut-off during construction period.