Experimental Research on Viscosity Characteristics of Grouting Slurry in a High Ground Temperature Environment

Abstract

The grouting method is a technical means to prevent and control the thermal damage of the tunnel with high ground temperature in the underground hot water area, and the viscosity characteristic of the slurry is the key factor of grouting treatment. When grouting in high ground temperature geological conditions, the slurry inevitably has both time-varying and temperature-varying characteristics of viscosity in the process of filling high-temperature fissures and plugging geothermal water. At present, the research on the viscosity characteristics of slurry at high temperature is rarely reported in the literature. In this paper, laboratory tests were carried out to measure the time-varying viscosity of ordinary cement slurry; cement-sodium silicate slurry, widely used in engineering; and high ground temperature grouting slurry (HGTGS), independently developed by our research group, at different preheating temperatures (20, 40, 60, 80 °C). The viscosity function curves of the three kinds of slurry were obtained by function fitting method, and the viscosity variation law of slurry was analyzed. The study found that the time-varying process of viscosity of the cement-sodium silicate slurry and the HGTGS in specific temperature conditions can be divided into two stages: The slow rising period of viscosity and the rapid rising period of viscosity. Whereas, the time-varying process of viscosity of ordinary cement slurry in specific temperature conditions includes only one stage of the slow rising period of viscosity. The viscosity of ordinary cement slurry and cement-sodium silicate slurry increases with the increase of temperature, while the viscosity of the HGTGS decreases with the increase of temperature. There are corresponding viscosity time-varying equations for the three kinds of slurry in different temperature conditions. The viscosity time-varying equation of the ordinary cement slurry accords with the linear function form, and the viscosity time-varying equation of the cement-sodium silicate slurry accords with the power-law function form. The viscosity time-varying equation of the HGTGS conforms to the exponential function form. On this basis, the unified description equation of the viscosity characteristics of grouting slurry in high ground temperature and the applicability of different types of grouting materials are obtained. This study has a certain reference value and guidance for theoretical analysis, numerical simulation and engineering application of grouting in high ground temperature environment.

Fracture Characteristics of Polyurethane Grouting Materials Based on Acoustic Emission Monitoring

“…is shear thinning phenomenon is caused by the reduction of flow resistance caused by the orientation, extension, deformation, or dispersion of particles in the fluid. e shear thinning phenomenon is reversible and can return to the original viscosity when the shear rate decreases or disappears [35,36].…”

Numerical Simulation of the Diffusion of Fissure Slurry at High Temperature

“…Xiao et al [39] analyzed the relationship between crack distribution and slurry characteristics based on discontinuous deformation theory and found that the amount of grout consumed by the crack network was subject to the normal distribution. Du et al [40] conducted a cement slurry diffusion test in zigzag cracks and discovered that the sealing efficiency of the high fractal dimension is greater than that of the low tortuous fractal dimension of the crack near the injection source, whereas the mode away from the grout source is the opposite [40].…”

Analysis of Damage and Permeability Evolution for Mudstone Material under Coupled Stress-Seepage

“…In the current theoretical analysis of seepage-stress damage coupling [ 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 ], the permeability evolution model cannot describe the characteristics of sudden permeability change after rock capacity expansion. According to the permeability evolution characteristics of mudstone, the sudden change of permeability evolution before and after capacity expansion in the process of total stress-strain is analyzed.…”