深部开采中岩爆岩块弹射速度的理论与实验

Theoretical and experimental study on rock block ejection velocity for rock burst found in deep mining

为预测岩爆灾害的破坏性,开展了岩爆过程中破碎岩块弹射速度的理论与实验研究。进行了真三轴卸载花岗岩岩爆的物理模拟实验,应用动态摩尔圆分析法,建立了岩爆过程中岩块弹射速度的理论模型;计算了岩块三种典型运动形式,即平抛弹射、斜上抛弹射、斜下抛弹射的弹射速度,并与岩爆实验得到的实验值进行了比较。研究结果表明:岩块弹射速度的理论计算值与实测值基本吻合。建立的岩块弹射速度的理论模型中涉及的应力参数为静态应力,而静态应力值可以应用地应力测试、应力监测,开采或开挖形成的应力集中理论在岩爆发生前获得。

In order to predict the intensity of a rock burst,theoretical and experimental investigation on the velocity of the ejected rock blocks during the rock burst were carried out.Laboratory rock burst experiment on granite samples was conducted using true-triaxial unloading apparatus. Theoretical models on the velocity of the ejected rock blocks were formulated.Velocities for rock blocks ejecting in the horizontal,oblique top and down directions were calculated using the formulae,which were then compared to the experimentally obtained values. The results show a good agreement.Stress parameters in the established theoretical models involve only the geostresses which can be obtained by in situ stress measurement and monitoring,or by the law of stress concentration caused by the excavation and mining activities.