Hydration process and rheological properties of cementitious grouting material

Grouting reinforcement is an effective technique for wide cracks of slope and complex formation. But the geological problems make them difficult to be filled as grouting materials easily run out before it solidified. To solve the issues, a new type of cement paste is developed, namely SJP grout (S-Sichuan, JP-Jinping), which is made up of cement and SJP additives. In this paper, the influence of the SJP additives on the early hydration process is investigated by hydration heat. The influence on the rheological and harden properties are investigated by viscosity and compressive strength. The results establish that the additives can adjust the cement hydration. It can effectively change the rate of hydration and extend the hydration time. The hydration degree of cement is improved directly. On its rheological properties, the grout has a high initial fluidity and time-varying behavior on viscosity. Pumpable time can adjust from 10 to 60 min and the final strength of the solidified grout is 15–25% higher than of common cement grout. Then this paper discusses a hydration model for SJP grout. The hydration model is divided into five stages of hydration and explains the reaction of every stage.