Research On Grouting And Blocking Water Technology And Resonable Forms Of Grouting Circle In Rich-Water Tunnel

Groundwater is a big problem in every stage of the tunnel construction for the long hydraulic tunnel. If there is any bad geological and hydrological condition, and without proper treatment in construction, groundwater always become a hidden danger of the hydraulic tunnel construction and operation, even cause inrush of clay and water and give a great threat to construction personnel and engineering equipment.The hydraulic tunnel of Muli hydropower stations, the research object of this paper, pass through multiple rich-water fault and fracture zone, where Karst water is abundant, Karst collapse and water and mud inrush may occur in the construction. So the discrete element models were established in this paper to research water plugging technology and reasonable forms of grouting circle under this geological condition, research results can provide some references for this and other similar projects. The main research contents and relevant conclusions are as follows:(1)Mesoscopic mechanics simulation of grouting processGrouting is an effective method to prevent water inrush in tunnel. Through studying the microscopic process of fracturing grouting and permeation grouting under different geological conditions, reasonable grouting pressure and layout of grouting hole was revealed under the conditions of different permeability coefficient and pressure of surrounding rock in this paper.(2)Research on grouting and blocking water measures in high-pressure and rich-water dissolved cavityFor the case of the high-pressure and rich-water dissolved cavity is located above the tunnel, the water plugging effect of different permeability coefficients and structure forms of grouting reinforced circle was studied in this paper, and reasonable grouting range and thickness of grouting circle under this geological conditions was put forward(2)Research on grouting and blocking water measures in rich-water faultFor the case of the rich-water fault is located under the tunnel, the effect on water inrush of different structure forms of grouting circle and drainage was researched, reasonable structure forms of grouting circle were put forward and the effectiveness of the drainage was confirmed. Then the water inrush processes under the conditions of different dip angle were studied, and the most likely locations of water inrush were determined under different dip angle.