Discrete element modeling of strata and surface movement induced by mining under open-pit final slope
Discrete element modeling of strata and surface movement induced by mining under open-pit final slope
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DOI：
10.1016/j.ijrmms.2016.07.006
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发表时间：
2016-10
影响因子：
7.2
通讯作者：
N. Xu;Jiayin Zhang;Hong Tian;Gang Mei;Quan Ge
中科院分区：
文献类型：
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作者：
N. Xu;Jiayin Zhang;Hong Tian;Gang Mei;Quan Ge
露天矿终坡下采矿会导致采空区围岩垮落和大位移运动。将节理岩体等同于连续体的数值方法难以模拟岩体的上述力学行为。但是，在计算模型中按照节点的实际分布特征放置节点，会导致模型块过多，导致无法进行计算。针对这一问题，本文提出了一种基于等效节理岩体模型（EJRM）的数值模拟方法。首先，将研究区岩体简化为EJRM；然后，采用正交设计与离散元法（DEM）数值模拟相结合的反分析方法对模型的力学参数进行反演；最后，利用DEM对露天矿边坡下开采引起的岩层和地表移动破坏进行了分析。本文以盐前山铁矿为例进行了研究。采用上述方法对该矿露天东坡下开采进行了模拟。得到了不同开采阶段岩层和边坡的破坏和移动规律。所提出的数值模拟方法可用于模拟地下开采引起的岩体复杂力学行为。
Ore mining under the open-pit final slope will result in caving and large displacement movement of rock-masses surrounding the goaf. It is difficult for numerical methods that equate jointed rock-masses to a continuum to simulate the aforementioned mechanical behavior of rock-masses. However, the placing of joints in a calculation model according to their actual distribution characteristics will result in an excess of model blocks, which renders the calculation impossible. To solve this problem, a numerical modeling method based on an Equivalent Jointed Rock-mass Model (EJRM) is proposed in this paper. First, the rock-masses in the research area are simplified as an EJRM; then, a back analysis method, combining orthogonal design and numerical simulation with Discrete Element Method (DEM), is used to invert the mechanical parameters of the model; lastly, the DEM is utilized to analyze the movement and failure of the strata and surface induced by mining under open-pit slope. The Yanqianshan iron ore mine was treated as an example in the present study. Mining under the eastern slope of the open pit of the mine was simulated by means of the aforementioned method. The patterns of the failure and movement of the strata and slope at different mining stages were obtained. This numerical modeling method proposed can be used to simulate complex mechanical behaviors of rock-masses induced by underground mining.