Influence of the inclination angles on the stress distribution in the bottom plate under the deep residual coal pillar.
Xianfeng Shi, Huan Yu, Guifeng Zhang, Haiyang Yi, Quande Wei, Xiaolong Zhang, Shifang Qin
Abstract
Open AccessProgressive deepening of coal extraction has directed attention to the objective transmission of floor stresses beneath inclined remnant pillars. Physical analogue experiments, three-dimensional finite-difference analyses (FLAC3D) and a semi-space elastic solution were jointly employed to quantify stress redistribution after panel extraction. The results reveal a bilateral arch-shaped failure zone within the roof strata and identify two characteristic floor-stress patterns that are governed by seam dip. For inclinations of 15-30°, near-floor stress exhibits quadratic decay from approximately 70 MPa to 25-30 MPa; for dips of 30-60° the decay is effectively linear, declining from 45 to 50 MPa to 15-20 MPa. The compiled data furnish a quantitative framework for panel layout and laminated-roof control in deep inclined seams.