自然崩落法矿山井下大规模开采综合评价及模拟技术

Comprehensive evaluation and simulation for large-scale mining using natural caving method

为降低矿山采用自然崩落法存在的风险,为后续井下安全大规模开采提供保障,对自然崩落法矿岩可崩性和崩落后的块度分布规律进行综合评价及模拟,提出一种矿岩可崩性三维数字化评价方法和矿岩崩落块度预测算法。通过对评价区域的三维建模,基于地质统计学理论将矿岩岩体参数推估反演到离散化后的矿岩工程模型中,根据三维节理面Monte Carlo模拟原理对矿岩崩落块度进行三维重现。将上述方法用于云南省普朗铜矿进行验证。研究结果表明:普朗铜矿III级和IV级矿岩质量分数之和为99.1%,矿岩可崩性级别为III至IV,适合应用自然崩落法开采;原始崩落块度等效尺寸大于1.65 m的块体筛上累积百分比为40%,建议普朗铜矿放矿口长×宽为5.00 m×5.00 m,此时放矿堵塞概率较小。

To reduce the risk of mining by natural caving method and to guarantee the safety of subsequent large-scale underground mining, the ore rock cavability and the fragmentation distribution were evaluated. Additionally, a three-dimensional digital evaluation method of ore rock cavability as well as an algorithm of was proposed. Through 3D modeling of evaluation regional, a discretized mineral engineering model was inversed with the parameters collocation of rock body based on geostatistics. Finally, the 3D caved block was rebuilt using Monte Carlo simulation. The above method was applied to Pulang Copper Mine, Yunnan Province. The results show that the mass fraction of level Ⅲ and IV rock is 99.1%, and the rock cavability level is Ⅲ to IV, it is suitable for natural caving mining. The percentage of original block equivalent size larger than 1.65 m is 40%. So the mouth size of Pulang Copper Mine is recommended 5 m × 5 m, and in which situation the possibility of ore blocking is less.