The study on the stress characteristics of backfill barricade in underground metal mines based on simulation experiments

With the widespread adoption of the backfill mining method in metal mines, the barricade wall, as a crucial structure for stope stability control, has its drainage performance and spatial placement significantly influencing structural stability. This study utilizes a self-developed force simulation device for backfill walls to systematically conduct mechanical tests on non-cemented backfill walls under various installation positions and drainage conditions. The results indicate that non-cemented slurry conforms to the ideal fluid model under undrained conditions, with lateral pressure distribution closely matching the hydrostatic pressure theory. Optimized drainage design can reduce lateral pressure by 70% and accelerate the dissipation process of pore water pressure. For drainage walls, their installation position can significantly regulate lateral pressure; when adjacent to the stope (entry), the peak lateral pressure reaches 73.18 kPa (under 80 kPa loading pressure), which is a 35.43% increase compared to the condition at the end of the entry. This research reveals the load transfer mechanism and pressure evolution规律 of non-cemented walls, providing theoretical support for mine safety protection design.