Experimental Study On The Law Of Slurry Diffusion And Reinforcement Mechanism Of Artificial Fracture Driven By Seepage And Hydrodynamic Force

With the continuous rapid economic development,a large number of underground projects have been put into construction,faced with increasingly complex geological and hydrological conditions,and often encountered geological disasters such as rock fissure seepage,water inrush and landslides caused by rock fragmentation,which caused construction safety accidents and brought people Economic losses,etc.Therefore,in view of the key scientific problems of water-rich broken surrounding rock,combined with grouting engineering as an important prevention and control method for seepage prevention and deformation,research on grouting reinforcement and seepage mechanism of fractures is carried out.This paper takes the Shangshi area of Tangxian County,Hubei Hubei Province as a geological prototype,uses theory and experiment methods to study the failure mechanism of grouting reinforcement of a single sawtooth structure surface,develops seepage-stress grouting devices,and develops fracture network hydrodynamics Grouting plugging mechanism.The research has reached some conclusions.(1)The engineering geological conditions of northern Hubei are discussed,and the nature of surrounding rock in Shangshi area of Tangxian County of the North Hubei Water Resources Project is analyzed.The nature of the surrounding rock is characterized by rock fragmentation and close hydraulic connection.It provides geological data for grouting design.(2)Aiming at the problem of fissure surrounding rock in Shangshi area of Tang County,the water resources allocation project in northern Hubei,direct shear test of artificial mortar sawtooth structural surface was carried out.According to the tunnel buried depth of 20m-65m,set normal stress(0.5MPa,1MPa and 2MPa),choose aluminate grout with different water cement ratio W/C(0.8,1,1.2)as the grouting material,and control the grouting thickness Below 0.5mm.The test results show that grouting can improve the reinforcement of surrounding rock.The larger the water-cement ratio,the greater the dispersion of the grouting shear peak,the smaller the cohesive force,and the internal friction angle does not change significantly.The smaller the water-cement ratio,the greater the cohesion.3DEC was used to analyze the crack growth,and indoor tests were performed to compare the numerical simulation model.(3)Through the seepage stress action of the fractured rock mass,the interaction system of the seepage field and the stress field of the North Hubei Water Resources Project was established,and the fracture network test system was developed.The test system includes:constant slurry system,hydrodynamic drive system,Loading system,effluent collection system,monitoring system,data acquisition software system.The test shows that the water-cement ratio affects the distance of slurry diffusion and the blocking effect.The larger the water-cement ratio,the longer the diffusion distance and the worse the blocking effect.The greater the water-cement ratio,the greater the water separation and the longer the initial setting time.Figure[68]table[3]references[82]...