Stability analysis of rib pillars in highwall mining under dynamic and static loads in open-pit coal mine

Abstract The retained coal in the end slope of an open-pit mine can be mined by highwall mining techniques. However, instability mechanism reserved rib pillar under dynamic loads haul trucks and static overlying strata is not clear, which restricts safe efficient application mining. In this study, load-bearing model was established, cusp catastrophe theory safety coefficient were considered, criterion equations stability proposed. Based on limit equilibrium theory, stress analyzed, calculation plastic zone width obtained. Winkler foundation beam elastic composed roof for compression developed. results showed that with increase width, total decreases nonlinearly, caused has a decisive role. Numerical simulation theoretical also performed study. numerical simulation, seam buried depth 122 m thickness 3 According to established system, it found when opening m, reasonable at least 1.3 factor 1.3. are good agreement calculation, verifies feasibility analysis stability. This research provides reference pillars