Dynamic response modeling of mine water flooding following grouting and rehabilitating of coalbed water-conducting channels

Abstract

Background: To optimize strategies for blocking coalbed aquifer water-conducting channels using grouting techniques.This study addresses dynamic water-blocking challenges in coalbed aquifers by introducing two novel materials—superabsorbent polymers (SAPs) and low-carbon cementitious materials (LCMs)—and developing optimized grouting strategies for hydrogeological pathway sealing. Methods: Based on the geological framework of Xinjulong Coal Mine, representative of East China mining conditions,multiscale experimental models were established to replicate three critical water-conducting systems: hydraulicallyconductive faults, karst collapse columns, and mining-disturbed aquifers with stress-induced fractures, with geological features reproduced at a 1:100 proportional scale. Results: The results demonstrate that SAPs achieved nearly 100% blocking efficiency in karst collapse columns within18 minutes, showcasing exceptional rapid sealing capability under high hydrodynamic pressure, while LCMs exhibitedhigh efficiency (89.4–91.4%) in sealing faults and mining-disturbed aquifers. These performances significantly surpassedthe predicted 80% reduction in mine water flooding volume. A grouting strategy classification system is proposed,systematically linking material selection to flow rate thresholds, with SAPs recommended for rapid, high-pressurescenarios and LCMs for sustainable fracture grouting applications. Conclusions: The findings provide a comprehensive solution for mine water hazard prevention that simultaneously supports sustainable mining practices and contributes to China's ‘Dual Carbon’ environmental goals, offering bothimmediate safety benefits and long-term environmental advantages.