Formulation and performance of nano-composite clay-cement based grouting materials in water-bearing sandy soil

Conventional cement grouts have limitations when dealing with water-bearing sandy soils due to their poor diffusion capacity and stability. Additionally, chemical materials are not only expensive but also environmentally harmful. This study proposes the use of nano-composite claycement based grouting material (CNGM) that takes advantage of the excellent synergistic interactions between cement slurry, clay, and nanocalcium carbonate. The manufacturing process for this material is straightforward. By conducting response surface methodology (RSM) experimental tests, the study effectively evaluates the influence of three independent variables (waterto-cement ratio, clay dosage, and nanocalcium carbonate dosage) on the performance of the CNGM. Furthermore, a matrix analysis model is presented to determine the optimal formulations for the CNGM. Under specific conditions, including a water-to-cement ratio of 0.8, a clay loading of 40 %, and a nanocalcium carbonate loading of 1.5 %, the resulting CNGM exhibits a threedimensional network structure and exceptional performance. The results of this research have the potential to significantly advance the development of grouting materials in water-bearing sandy soils.