Performance assessment of a newly developed and highly stable grouting material for a completely weathered granite dam foundation

Abstract

Grouting is one of the most important techniques in anti-seepage and reinforcements of sandy soil dam foundations. However, there is a lack of stable grouting materials as the existing materials show many limitations. This paper proposed a new grouting material to improve the anti-seepage and mechanical performance of completely weathered granite. This grout of desirable groutability, stability, and strength was produced by wet grinding clay cement slurry. The effects of different clay contents and water–solid ratios on the engineering properties of the grouting material and the formation mechanism of the slurry were studied through a series of laboratory experiments. The optimal formulations of the grout were determined by comparing the engineering performance of the new grout with of the superfine cement slurry and the wet-ground fine cement slurry. The recommended parameters for the new grout included a specific gravity of 1.15 for the clay slurry and a water–solid ratio of 1.0 (the mass proportions of clay and cement to the total solids are 25% and 75%, respectively). Finally, a grouting simulation experiment and a field grouting test were conducted to verify the groutability and effectiveness of the proposed grouting material. The results indicate that the grout is an economical and environmentally friendly grouting material with good groutability.