地下矿山裂隙岩体结构均质区三维划分方法研究

Three-dimensional demarcation method of homogeneous structural domains of jointed rock masses at underground mine

针对现有岩体结构均质区划分方法应用于地下矿山时存在细节辨识能力偏弱等问题,开展地下矿山岩体结构均质区三维精确划分方法研究。以广西铜坑矿锌多金属矿体3^#矿块为例,从岩体空间结构展布特性出发,构建由确定性与随机性结构面耦合的裂隙岩体三维模型;将岩体模型正交网格离散化,并选取模型网格子区的块体化程度值为均质区划分判据;利用K-means算法衡量不同数据源(网格)的相似性,结合误差平方和(SSE)度量聚类质量;最后重构三维岩体结构均质区,形成了一种地下矿山岩体结构均质区三维划分方法。研究成果表明:利用该方法能够从三维角度精确划分地下矿山岩体结构均质区,可为后续岩体质量评价及岩体离散元模拟的模型构建等工作提供有益参考。

The failure to characterize subtle difference would occur when the existing available methods were used to identify the structural domain boundaries of rock masses at underground mine.Here,research on the three-dimensional refined demarcation of homogeneous structural domains of jointed rock masses at underground mine was carried out,and geological survey data of the No.3 block of the Zn polymetallic orebody in Tongkeng Mine (China) was used to demonstrate the validity of the method.In view of the spatial structure of jointed rock masses,a three-dimensional structural network model of the jointed rock mass at the underground mine was built based on the coupling of deterministic-stochastic discontinuities,and the model was subsequently discretized with orthogonal meshes.The values of the blockiness levels of the meshes were adopted to determine the homogeneous structural domain boundaries.The K-means clustering algorithm was used to test the similarities of data sources (i.e.,meshes),and the sum of squared error (SSE) was employed to measure the quality of clustering.Finally,the rock mass structural domains were reconstructed from the perspective of three dimensions,and the method to three-dimensionally demarcate the homogeneous structural domains of rock masses was consequently formulated.The result shows that the method could accurately divide the structural domains of rock masses in three dimensions and provide a beneficial reference to the subsequent research works (e.g.,rock mass quality evaluation and DEM simulation).