流变断裂型矿岩自然崩落速率模拟预测

Prediction for Block Caving Velocity of Rheologic Fracture Ore-Rock

矿岩自然崩落速率预测是一个涉及崩落规律和崩落与时间相依关系的复杂动态过程,通过数值模拟的方法,对流变断裂型矿岩的自然崩落规律和崩落速率进行了模拟研究.研究表明:对于单一的拉底工程,矿岩破坏首先从拉底区上部中间开始,成拱形向上发展.当拉底面积达到一定值后,在拉底顶板中心位置将出现大范围的拉应力区,矿石的自然崩落主要是拉伸破坏引起,矿岩在其自重作用下脱离母体,产生初始崩落;当拉底面积继续增大并达到某个量值时,矿岩达到持续崩落.矿岩崩落预测将为合理、经济安排生产计划和生产设计提供有力依据.

Prediction for block caving velocity of ore-rock is a complex dynamic process that relates to the caving rule and to the relation between caving and time. Block caving rule and caving velocity of rheologic fracture ore-rock were numerically simulated in this paper, showing that the failure of ore-rock starts from the central roof of undercut field to the single undercut engineering, and develops upward in an arch shaped form. When the undercut area reaches a certain value, a wide tensile stress region will be formed in the undercut central roof. So, the block caving of ore-rock is caused mainly by tensile failure and the cracked ore-rock will be separated from its parent rock under the action of gravity of the ore-rock its own and will begin the initial caving. With the undercut area enlarging and reaching a certain value, the persistent caving will occur. The prediction for block caving velocity of ore-rock has provided a foundation for us to make production plan economically and scientifically.