School of Resources and Civil Engineering, Northeastern University, Shenyang, Liaoning Province, China.
PLoS One. 2018 Aug 15;13(8):e0202221. doi: 10.1371/journal.pone.0202221. eCollection 2018.
Critical medium column theory has typically been used to predict the scope of caved rock zone (CRZ) caused by caving mining method. It is essential to understand the distribution laws of lateral pressure induced by caving mining method with different dipping angles. In this study, a self-designed scaled physical model was used to investigate the distribution laws with angles ranging from 80° to 90°, and ore drawing was employed in experiments to simulate caving mining method. The experimental results indicated that the distribution laws were divided into the reductive region and the extensive region during ore drawing. The reductive region was close to the drawing hole, and its scope was smaller than the other part. Moreover, decreasing the dipping angle was an effective way of controlling the maximum reduction rates and the scope of reductive region. By varying laws of lateral pressure, the predictive model of CRZs' scope was established. Additionally, the rock mass located outside the predictive CRZs' scope did not rupture based on the monitoring of Digital Optical Televiewing (OPTV), which was verified by the field test in Dabeishan Iron Mine, China. The results of the field test demonstrated that the prediction method used in this study was valid and could be used in practice.
关键介质柱理论通常用于预测崩落采矿法引起的崩落围岩范围。了解不同倾角崩落采矿法引起的水平应力分布规律至关重要。本研究采用自行设计的相似物理模型，研究了倾角为 80°~90°的分布规律，并采用出矿模拟崩落采矿法进行实验。实验结果表明，出矿过程中，分布规律分为缩减区和扩展区。缩减区靠近出矿口，其范围小于其他部分。此外，减小倾角是控制最大缩减率和缩减区范围的有效方法。通过变化的水平应力规律，建立了崩落围岩范围的预测模型。此外，根据数字光电视（OPTV）监测，位于预测崩落围岩范围之外的岩体没有破裂，这在中国大贝山铁矿的现场试验中得到了验证。现场试验结果表明，本研究中使用的预测方法是有效的，可以在实践中应用。
