Study on the diffusion law of dynamic water grouting in fracture with slurry-rock stress coupling effect

Water inrush disasters in geotechnical engineering are mainly caused by seepage in fractures, and curtain grouting is the most common method to block water flow. To ensure the efficacy of the water blocking curtain, it is necessary to study the slurry’s diffusion pattern. In this study, by means of laboratory experiments and theoretical deductions, the grout diffusion morphology in fractures with the slurry-rock stress coupling effect is revealed, and the corresponding theoretical model is established. First, based on the failure of water-blocking curtain in a hydropower station in Yunnan Province, a four-level four-factor orthogonal table was set up, grouting experiments were conducted using the self-developed fracture grouting device, and the relationship between the main influencing factors and fracture deformation and grout diffusion distance was revealed. Then, based on the Bingham fluid constitutive model, fracture deformation equation and grouting model with flowing water, a new fracture grouting model considering the coupling effect of slurry-rock stress was established. Finally, based on the calculations and experiments, the morphology of slurry diffusion is described, thereby proving the validity of the new model.