Instability prediction model of remaining coal pillars under remining disturbance

To address the instability timing problem of residual coal pillars under mining disturbance, their stress migration law and mechanism were studied via numerical simulation, physical engineering tests considering remining in 3101 working face Shenghua Coal Industry. The results show that as progresses, concentrates on both sides remaining pillar empty roadway. When first front loses its bearing capacity, is transmitted forward, resulting advanced collapse roadway roof an excessive load second face. Additionally, critical value prediction model stability safety factor f s ${f}_{{\rm{s}}}$ was constructed. If less than during repeated period, must be reinforced. A hollow grouting crossed anchor selected for reinforcement; thus, realizing safe pillars. Our research provide theoretical support secondary China similar mines worldwide.