高地应力区域动载扰动诱发深埋巷道冲击致灾机理研究

    Study on Mechanism of Deep Roadway Rock Burst Induced by Dynamic Load in High Ground Stress Region

    • 摘要: 为了探讨高地应力控制区动载作用下诱发巷道冲击地压机理,基于弹性力学理论,建立了不同侧压系数影响下深埋动载巷道围岩力学模型,推导出了诱发巷道冲击的力学判据,并运用FLAC软件模拟分析动载巷道围岩应力及弹性能演化规律。研究结果表明:深埋巷道冲击受多重因素的共同作用,巷道埋深越大,地应力越大且震源距巷道自由面较近,围岩极易发生冲击;动载巷道围岩应力随着侧压系数的增加发生了明显的变化,巷帮垂直应力较顶板显著增大,且其弹性能量值均在距巷道水平4 m位置处达到最大;由于最大剩余弹性应变能距巷道自由面较近,围岩处于极限平衡状态,动载作用下巷道围岩裂隙进一步扩展贯通,蓄积高弹性能得到释放,易诱发巷道冲击。

       

      Abstract: In order to discuss mechanism of roadway rock burst induced by dynamic load in the control area of high ground stress, based on theory of elastic mechanics, the mechanics model of deep dynamic roadway, the mechanical criterion of roadway rock burst was derived. And, stress and elastic energy evolution laws of dynamic roadway surrounding rock were analyzed by using FLAC simulation software. Results show that rock burst of buried deep roadway is affected by multiple factors. The deeper roadway is, the greater ground stress is, and the distance between source and free surface of roadway is close, and surrounding rock is easily impacted. With increase of lateral pressure coefficient, the stress of dynamic roadway surrounding rock changes obviously. The vertical stress of the roadway is significantly larger than that of roof. The elastic energy value reaches the maximum in the 4 m horizontal position of roadway. However, the maximum residual elastic strain energy of roadway is closed to surface, and surrounding rock is in the limit equilibrium state. The crack of surrounding rock is further expanded under action of dynamic loading, and the accumulation of high elastic energy can be released, thus, rock burst of roadway is induced.

       

    /

    返回文章
    返回