Experimental study on temperature characterization during cement grouting reinforcement

Abstract

Grouting is a common reinforcement method for underground projects. However, with the hidden nature of grouting reinforcement projects, the grouting reinforcement effect is difficult to detect and evaluate, and the accuracy of existing testing technologies needs to be improved. Considering the heat generated during the hydration of the cement grout, this paper proposes to check the effect of grouting reinforcement based on the temperature change. The law of temperature changes in cement grouting reinforcement was studied by indoor tests and validated by the wave speed test. The results revealed a similar law in temperature changes when cement grouts with different water–cement ratios were used for reinforcement in various media. Specifically, grout hydration was completed within 48 h and tended to be stable, and the hydration temperature maximized 14–20 h after the start of grouting. The results of the wave speed test showed that the wave speed increased continuously during the first 24 h and stabilized after 48 h, indicating a relationship between the strength increase of geotechnical media and the temperature change after grouting. Therefore, the temperature change during cement grout hydration is a parameter that can characterize the grouting reinforcement effect. The results provide a basis for further exploration of efficient and accurate testing and evaluation methods for the grouting reinforcement effect.