Abstract: The viscosity of fluid is time-dependent, which has an important influence on building grout diffusion model. Combining with rheological equation of Bingham fluid and time-dependent characteristic of fluid viscosity, the rheological equation and seepage motion equation based on Bingham fluid of time-dependent behavior of viscosity were established. According to some assumptions，column–hemispherical penetration grouting mechanism about them was deduced and the relationship was also probed into between diffusion radius l1 of hemispheroid and diffusion length m belongs to cylinder: m=(2l1 /3)(2n+1). Then they were validated by means of designing indoor grouting experiments. Experiment results show that in term of diffusion radius of hemispheroid, diffusion length belongs to cylinder and volume of grouting diffusion body, theoretical values calculated by column-hemispherical penetration mechanism formula in view of Bingham fluid of time-dependent behavior of viscosity have respectively about 15%, 10% and 40% of the differences with the actual measurement values by indoor grouting experiments; but they are all within the acceptable error limits. Therefore, it could better reflect column-hemispherical grouting infiltration law based on Bingham fluid of time-dependent behavior of viscosity in the general and may play a guiding role and provide some reference valuable in the design, construction and theoretical research of grouting technique.

Key words: time-dependent behavior of viscosity, Bingham fluid, column-hemispherical penetration grouting mechanism.