回撤通道保护煤柱应力分布及其影响因素分析

Research on stress distribution and impact parameters of protective coal pillar at retracement channel

基于理论分析方法,针对综采工作面末采阶段老顶在回撤通道保护煤柱上方断裂这一破坏形式建立力学分析模型,研究了保护煤柱在这一破坏形式下的应力分布规律,并分析相关参数对保护煤柱应力的影响规律。研究结果表明,老顶在保护煤柱上方断裂时,应力峰值偏向辅回撤通道一侧,且老顶断裂位置和留设宽度对煤柱的应力分布形式影响很大,其对末采阶段保护煤柱和回撤通道的围岩稳定起关键作用,在进行回撤通道保护煤柱宽度设计时,应充分考虑上述因素对煤柱稳定性的影响,对保护煤柱留设宽度进行合理优化,保证工作面回撤过程中的围岩稳定性。

According to the failure mode of main roof fracture position above protective coal pillar at retracement channel at the ending stage of fully mechanized face,established the mechanical model and studied the stress distribution law and analyzed the influence of relevant parameters on stress of protecrive pillar.The results showed that the peak stress was closer to the secondary retracement channel when the fracture position was above the protective coal pillar,and the fracture position and coal pillar width had great influence on the form of stress distribution.In the coal pillar width design process,the influence of those factors on coal pillar stability should be fully considered.By rational optimization can the width of protective coal pillar ensure the stability of the surrounding rock in retracement channel.