【作者】 李刚；

【导师】 慕青松；

【作者基本信息】 兰州大学 ， 工程力学， 2011， 硕士

【摘要】 冲击矿压事故是矿山开采过程中突发性的危害巨大的地质灾害。随着国内外矿山采掘深度的不断加大,冲击矿压灾害会在未来多年内变得愈加显著和突出。本文共有两大部分。第一,在综合分析金川矿区龙首矿的开采历史与对其稳定性的研究的基础上,建立了三维ANSYS有限元模型,模拟了在上盘贫矿大面积连续开采过程中保安矿柱的受力、变形与稳定性,与以前的工作进行比较,指出大面积连续开采相较于对富矿的开采对保安矿柱的影响要大得多,同时,应力集中现象愈发严重,威胁着露天坑边坡与保安矿柱的稳定与安全。并应用安全因子对保安矿柱的安全性进行了评估,得到的结果可用于指导工程实践。第二,受三维模拟过程中对保安矿柱稳定性的分析的启发,应用岩石物理学中的压机-岩样模型的原理提出了分析矿柱受压失稳条件的梁-柱模型与半无限体-柱模型,从变分原理的角度出发分析了矿柱受压失稳的力学机制。然后应用该模型对工程实际中的失稳事故进行分析,从本文的角度指出失稳发生的原因。进而提出了一些降低生产事故发生率、优化采矿方案的有参考价值的意见和建议。更多还原

【Abstract】 Rock burst is a kind of sudden happening geological hazard that makes great damage in mining process. With the mining depth increasing, rock burst hazard will become more significant and prominent. This article has two parts. First, on the basis of comprehensively analyzing the mining history and its stability, this work established a three-dimensional ANSYS finite element model and simulated the large areas continuous mining process of the lean ore of the upper plate. The results of the simulation include the stress, strain and the stability of the safety pillar. Compared with the results of previous works, we find that the influence of the lean ore mining is much more obvious compared with the mining of the rich ore. During the mining process, stress concentration in the safety pillar is becoming more and more serious, and threatens the security of the open pit slope. Using adaptable strength theories on the simulation results, we evaluate the security of the safety pillar and get conclusions being consistent with the practical conditions. Second, inspired by the press model of rock samples, we proposed two models to determine the instability conditions of a pressed ore pillar through a series of simplifications. Then apply the models established to analyze instability incidents in the practical engineering and point out reasons for the instability. At last, several comments and suggestions are proposed to lower the rate of accidents and optimize the mining program.更多还原