崩落法开采岩层移动影响因素的数值模拟

Numerical Simulation of Factors Affecting Strata Movement Caused by Caving Method

随着矿山开采深度的增加,岩体所处的力学条件变得复杂,采用崩落法开采的深部矿体岩层移动规律受多种因素影响且不同于浅部。离散元法是基于不连续性假设的数值方法,它特别适合于求解节理岩体中的非连续性问题。基于离散元理论,采用数值计算软件3DEC,分析了不同节理倾角、不同侧压力系数及不同开挖阶段对深部矿体崩落法开采过程中岩层移动规律的影响,研究结果表明:不同倾角的优势结构面对崩落发展趋势影响显著,水平节理对崩落发展有良好促进作用;侧压力系数越大,崩落高度越小;深部矿体开采过程中,由于承压拱的存在,开采高度为120 m时,并未引起大范围塌陷。研究结果可为深部矿体崩落法开采岩层移动规律及地表沉陷范围的确定提供一定的参考依据。

With the increase of mining depth, rock mechanics conditions become complicated. Strata movement law of deep mining by caving method is affected by many factors and is different from the shallow. Discrete element method is a nu- merical method based on the assumption of discontinuity, which is particularly suitable for solving the discontinuity problem of jointed rock mass. Based on the discrete element theory, using numerical calculation software 3DEC, the rock movement law af- fected by different joint angle, different lateral pressure coefficients and different stages of excavation during caving process of deep ore body were analyzed. The results showed ： Dominant structural plane with different dip angle had a significant influence on caving trends. And horizontal joints had a good role in promoting the development of caving;The larger lateral pressure coef- ficient, the smaller the height caving;During the mining process, large-scale subsidence did not occur when the mining height was 120 m because of bearing arch. The results can provide a frame of reference for determining for the law of strata movement and surface subsidence range of deep ore caving mining method.