Hydrogeological Analysis and Control of Groundwater Inrush for the Second Time in an Inclined Shaft

A groundwater inrush occurred again when the auxiliary inclined shaft which excavation came to the pregrouting interval, which submersed the shaft of the Heilong Coalmine, Shanxi Province. The main cause was the poorness of the fracture stability, which formed during the interaction of soft clay and grout in the first grouting process. The method “distributary to relieve pressure then prevent water inflow” was taken, that was to change the uncontrollable gushing to controllable gushing then grouting. Last, borehole was used to examine the effect of the grouting, the results showed that the effect was good. The paper provides reference for similar grouting in rock mass which filled with soft clay.