Study on the diffusion mechanism of columnar-hemispherical infiltration grouting form of quick-setting slurry considering spatial and temporal variations of slurry viscosity

The time-varying viscosity of quick-setting slurries will cause the spatial variation of slurry viscosity, which has an important impact on the diffusion mechanism of infiltration grouting. With the time-varying Bingham fluid constitutive model and the uniform capillary group theory, a cylindrical–hemispherical slurry infiltration diffusion model was established, considering the time-space variation of slurry viscosity. According to the soil parameters and slurry rheological parameters, the slurry pressure can be calculated at different diffusion radius and times. The effects of the permeability, porosity, and grouting rate of the injected medium on the grouting pressure and grouting diffusion radius were analyzed. The medium porosity is very critical for the design of the slurry diffusion radius. A 3-dimensional infiltration grouting test was carried out. The infiltration grouting pressure under different grouting rates and soil parameters were obtained. The results obtained from theoretical model were compared and verified with the test results. The results show that the grouting pressures calculated from the infiltration diffusion model proposed in this paper are in agreement with the experimental results. The grouting pressure calculated by the theoretical model is 1.05–1.25 times of the experimental value.