To address the high carbon emissions and low resource utilization of traditional grouting materials used for the reinforcement of karst strata with dynamic water, this study developed a low-carbon and sustainable clay-cement grout. Aligned with the demand for high-performance, sustainable construction materials, the grout was formulated by partially replacing cement with natural clay and incorporating an admixture derived from industrial by-products, which is mainly composed of aluminum, silicon and calcium oxides. The optimal mixture ratio, involving the specific gravity of the clay slurry, cement content and admixture content, was determined through orthogonal tests. The optimized material maintained good fluidity and a low bleeding rate, while the 28 days compressive strength of its concretions reached 1.49 MPa. Simulation tests were conducted using a self-developed indoor dynamic water grouting device to compare the reinforcement performance of this material under pulsating and constant-pressure grouting modes. The results indicated that pulsating grouting could further enhance the compactness and compressive strength of the concretion. This material and process were successfully applied in an anti-seepage reinforcement project for a karst dam foundation, forming a continuous and effective impervious grout curtain. This material–process–application integrated approach was validated, demonstrating that the synergistic use of the developed low-carbon clay-cement composite with pulsating grouting technology provides an effective solution for grouting in karst strata with dynamic water. This study offers a valuable reference for the development of low-carbon, high-performance geotechnical reinforcement materials.
Yang et al. (Wed,) studied this question.