Abstract:

A largescale water gushed from tunnel floor due to the ample water supply on the ground surface during the construction of a tunnel crossing the contact zone between fracture evaporite solution breccia and complete gypsum layer, which brought serious destructions and threatens to the surrounding environments. As a result, some effective measures have to be took to control water gushing. In this paper, comparison and contrast is made among several grouting methods. With the treating principle of “drainage first and then sealing, radial grouting reinforcement first and then tunnel floor sealing, and centralized treatment of local part”, the water gushing speed is slowed down, the surrounding rock permeability coefficient is reduced, the tunnel structure stability is improved and the ground water is brought under effective control by using radial grouting and deephole grouting.

Key words: tunnel, water gushed from tunnel floor, cause analysis, deephole grouting