Study On The Mechanism Of Grouting Diffusion Of Bingham Grouts With Viscosity Variation

With the development of engineering construction in tunnel, mining and other fields in our country, the grouting technique has been widely used in projects to deal with all kinds of complicated geological conditions. According to the different indicators, grouting engineering can be divided into various types, this paper mainly studies the application of permeation grouting. Grouting pressure and the diffusion range in practical engineering are two important parameters. It’s not economic when the range is too big, and unsafe when too small. Therefore it needs the theory of reasonable and effective guidance to achieve the goal of safe and economic optimum.Though the theoretical formulas have been discussed in some articles, but mostly flawed, few scholars consider the viscosity change with time of the properties of grouting body. In this paper, on the basis of predecessors’ research, mainly for the following research:Researched the Bingham cement slurry viscosity varying with time in conditions of some water cement ratios, and has got the formula;Combined with the percolation mechanics, fluid mechanics and soil mechanics, when considering viscosity varying, modified the formulas of permeation grouting, has got the formulas to calculate the diffusion range and pressure as well as impacted by some various factors;Based on the continuity and momentum equations for the fluid diffusion, fracture flow diffusion equation for Bingham fluid was derived, and summarized the pressure attenuation law, discussed the impact of various factors on the spread of slurry;Simulated the slurry diffusion process with software FLAC3D, to summarize the seepage law of change of fluid viscosity, and constant viscosity is compared. It also compares the calculation results of theoretical formulas.