Experimental study on anti-dispersion performance and microscopic mechanisms of fully solid waste-based grouting materials
摘要
In karst regions, leakage control remains a considerable challenge owing to the presence of highly dynamic groundwater systems and intricate seepage networks. Conventional grouting materials often fail to achieve a synergistic balance of low-carbon emissions, strong anti-dispersion performance, and structural stability, limiting their effectiveness in karst leakage control. In this study, a fully solid waste-based anti-dispersion grouting material (FSWAG) was developed using ground granulated blast furnace slag (GGBS), red mud (RM), calcium carbide slag (CS), and fly ash (FA), without external chemical activators. Functional additives, including water reducer, setting accelerator, defoaming agent, and flocculating agent, were incorporated to improve grout anti-dispersion performance. A multifactorial orthogonal design and range analysis were employed to optimize formulation parameters, including fluidity, setting time, turbidity, unconfined compressive strength, and hydraulic conductivity. The optimized mix A4B4C2D3 achieved a flow spread of 175 mm, rapid setting (52 min), low turbidity (120 NTU), a 28 d compressive strength of 14.17 MPa, and excellent impermeability (1.02 × 10−10 m/s). Microscopic analyses (XRD, FTIR, MIP, and SEM) revealed that additive synergy promoted gel formation and microstructural densification. Production-stage analyses demonstrated a 67% reduction in binder cost and a 98% reduction in CO2 emissions relative to cement-based systems, while the total formulation cost reduced by 71% compared with commercial products. Heavy-metal leaching tests further confirmed environmental safety. These results highlight the potential of FSWAG as a sustainable, high-performance grouting material for leakage control in complex geological settings.