The role of the advancement direction of the coal mining face on subsidence in sloped areas

This study investigates how changes in the mining face direction beneath a slope influence surface subsidence. Using a case study from a Shanxi Province coal mine, we employed combined theoretical and numerical analysis to evaluate slope surface deformation and overburden stress-strain characteristics, from which governing principles were derived. The results indicated that: The variation in the angle between the coal mining face’s advance direction and the dip direction primarily influences the spatial morphology of the subsidence basin, with limited impact on the overall subsidence volume. Roof subsidence exhibits distinct spatial characteristics: subsidence increases progressively on the side of the face moving uphill, while it correspondingly decreases on the side moving downhill. A trigonometric quantitative relationship exists between the angle and both the maximum surface settlement and the maximum horizontal displacement parallel to the slope direction. Therefore, when designing the advance direction, controlling the angle within the range of 90° to 180° can effectively reduce the magnitude of surface deformation, mitigate impacts on slope stability, and alleviate landslide risks.