The Diffusion Rule And Plugging Mechanism Of Grout In Fracture Presented In Rock Under Coupling Of Heat And Flow

The water inrush in the process of underground engineering has caused a large number of people and property loss.To solve this problem,grouting technology has become the first choice for treatment and prevention of underground water inrush due to many advantages such as simplicity,safety and reliability,lower cost and so on.At present,there are some short point in diffusion rule and plugging mechanism of grout in fracture presented in rock under coupling of heat and flow.This paper takes widely used grouting material,cement-sodium silicate slurry as research object.The engineering properties and diffusion laws of the slurry under the influence of temperature are studied.In addition,some results have been gor.(1)The results show that the viscosity of the slurry increased first and then decreased with the increase of the viscosity of the slurry.The viscosity of the slurry was the largest when the ambient temperature was 40 C,and the gelation time of the slurry decreased with the increase of time.The higher the temperature,the shorter the gel time.The test results of the simulated grouting platform show that the diffusion speed of cement water glass slurry gradually slows down with the increase of grouting time.With the rise of the ambient temperature,the unit time of grout diffusion time has increased by about 10%.In the process of increasing direction angle from 0 degrees to 180 degrees,the diffusion distance of the slurry decreased by 17%-20% due to the action of hydrodynamic pressure.(2)Combination of Bingham fluid equation,mathematical model of slurry diffusion are single tubular and plane cracks.In the analysis of the grouting parameters in the mathematical model shown that in the early stage of the grouting project,the slurry spread rapidly in the pipe and plane fissures.With time going,the slurry diffusion is becoming slower and slower.The grouting pressure is positively correlated with the diffusion distance and the diffusion law.Moreover,the dynamic water pressure and the viscosity of the slurry are negatively correlated with the diffusion distance of the slurry.(3)The corresponding large-scale grouting experimental platform is constructed.The rule of slurry diffusion is verified by comparing the theoretical data obtained from the diffusion radius data obtained from laboratory tests and mathematical models.The experimental results show that the derivation of the mathematical model is slightly larger than the actual test results.Among them,the diffusing distance of grout in the tubular fracture is different from the actual test result,and the difference between the grout diffusion distance in the horizontal fracture and the actual test is about 10%.The difference is between 3%-8%.It is more successful to verify the feasibility of the grouting model.(4)In view of the common technology in grouting engineering,the finite element numerical analysis software is applied to simulate the grouting instance,simulate thechange of pore pressure field in grouting engineering,and evaluate the grouting effect through the change of pore water pressure field.