Abstract: In order to improve the grouting quality of reinforcement, anti-seepage plugging and other projects, it is necessary to adjust rheological properties of grouting materials by adding modifiers. The effects of two modifiers (early strength grouting modifier SX-ZJ-Z and high strength grouting modifier SX-ZJ-G) on rheological properties of grouting materials were studied, and their setting time, fluidity, plastic viscosity and yield stress were tested at different content (10% and 20%,mass fraction) and water-to-binder ratios (W/B=0.25, 0.30, 0.35 and 0.40), and the degree of fitting of Bingham model and Modified Bingham model to their rheological curves was analyzed. The results show that the addition of SX-ZJ-G significantly prolonges coagulation time of grouting materials, while the addition of SX-ZJ-Z shortenes setting time of grouting materials. The addition of SX-ZJ-G exerts the “ball” effect and greatly improves fluidity of grouting materials, but the addition of SZ-ZJ-Z has almost no effect on fluidity of grouting materials. The addition of modifier changes the cement slurry from Newtonian fluid to yield-stress-fluid, showing a nonlinear shear stress curve, and Modified Bingham model had a good fitting effect compared with the Bingham model. When W/B=0.30, 0.35 and 0.40, the addition of SX-ZJ-Z has little effect on plastic viscosity and yield stress of grouting materials. The addition of SX-ZJ-G greatly reduces plastic viscosity and yield stress of cement slurry by more than 90%, and improves rheological properties of grouting materials.

Key words: grouting material, rheological property, fluidity, setting time, plastic viscosity, yield stress