动压软岩巷道围岩破坏机理及强化技术研究

Study on failure mechanism and strengthening technology of soft rock roadway under dynamic pressure

针对曹村煤矿500水平大巷动压影响剧烈、变形破坏严重的问题,采用理论分析、数值模拟及现场实测等方法,分析了软岩大巷破坏的关键诱因,研究了动压影响下围岩的变形破坏机理。研究结果表明:动压打破围岩原应力平衡并增幅围岩主应力,导致弹塑性区分界面岩体强度-应力耦合失衡,分界面向岩体内部转移,围岩破坏范围增大、承载强度弱化。针对性地提出了动压软岩巷道围岩控制理念及强化方案,矿压观测表明,强化方案应用后围岩变形量及变形速度均大幅降低,动压影响期间的巷道变形明显得到控制。

Aiming at the problem of severe deformation in No. 500 main roadway in Caocun Coal Mine influenced by dynamic pressure,the key factors of soft rock roadway damage were analyzed and the deformation mechanism was studied with the methods of theoretical analysis,numerical simulation and field measurement. The results show that the dynamic pressure can break the balance of the original stress and increase the main stress in the surrounding rock,resulting in the imbalance of rock strength and stress in elastic-plastic boundary. The boundary transfers to the deep leading to increase of the rock failure scope and weakening of the bearing capacity. The control concept and strengthening plan of surrounding rock under dynamic pressure were put forward. Pressure observation shows that the amount and speed of surrounding rock deformation decreases significantly,and the roadway deformation during dynamic pressure is obviously controlled.