Performance enhancement of silica fume-modified double-liquid grouting material in water-rich environment

To address the issues of poor water-stopping performance, low durability, and slow post-curing strength growth in conventional grouting materials under water-rich corrosive environments, this study developed a silica fume-modified double-liquid grouting material designed to enhance its water resistance performance in such conditions. In particular, the effects of water-cement (W/C) ratios, silica fume (SF) content, cement to sodium silicate (C/S) ratio, and polycarboxylate superplasticizer (PCE) dosage on material performance are systematically investigated using the orthogonal test and range analysis method, and the optimal proportion is determined accordingly. The water resistance performance of the optimized silica fume-modified double-liquid grouting material is then assessed, focusing on its stability, rheology, and durability etc. Results indicate that the optimized grouting material exhibits good water resistance performance, with significant improvements in stability, strength, rheology, and durability compared to conventional grouting material. To better reveal the mechanism of performance modification for the optimized grouting material, the microscopic test analysis was conducted, and the results indicated that the optimized grouting material has a relatively uniform and dense structure, with fewer cracks and pores. In addition, the optimized grouting material offers a significant economic and environmental benefit. This study provides a viable solution to mitigate water inrush and leakage issues for grouting material in a water-rich environment.