宁都硫铁矿缓倾斜矿体采场结构参数及回采顺序优化研究

发布时间：2019-03-27 20:23

【摘要】：宁都硫铁矿是缓倾斜矿体,开采难度较大,目前矿山采用采矿方法不统一,且采场安全系数和回采率低,为实现矿山高效、安全、经济开采,合理选择其采矿方法和优化其采场结构参数成为矿山当下首要任务。本文采用层次分析和模糊数学综合法对矿山采矿方法进行了选择,并通过理论计算和数值分析的方法优化了该矿采场结构参数和回采顺序,得出的主要结论如下:(1)运用层次分析法与模糊数学原理,建立了宁都硫铁矿采矿方案的综合评判模型,科学合理地选出了该矿最优采矿方案。在优选过程中,综合考虑影响采矿方案的各项影响因素,利用层次分析法确定各评价指标的权重,并根据模糊数学原理对备选采矿方案进行综合评判,计算结果得出房柱采矿法为该矿最优采矿方法。(2)以安全系数为矿柱稳定性评判指标,采用正交极差理论对影响矿柱稳定性的因素进行了敏感度排序,得出矿房跨度和矿柱尺寸敏感度最大,并通过光弹性试验结论得出的经验公式计算得到矿房极限跨度,在此基础上利用尖点突变理论建立矿柱失稳模型,得到临界矿柱宽。本文还综合弹性力学法、结构力学法、材料力学法在不同矿房跨度下计算得到的顶柱厚,对其全部结果进行拟合分析,推出了适合宁都硫铁矿顶柱跨度和顶柱厚的关系式。最终得出矿房极限跨度14.22m,最小矿柱宽3.99m,顶柱厚3m,为后续采场数值模拟提供了依据。(3)根据现场实际和理论计算结果确定不同的采场结构参数,并采用正交试验法设计不同的方案组合,综合利用ANSYS和FLAC3D软件对不同采场进行模拟。比较不同方案采场的应力、位移和塑性区,筛选出安全方案,以采场关键部位应力、位移、塑性区及回采率作为评判各方案优越度的指标,建立综合评判模型,并确定各指标权重,评价得到矿房跨度14m,点柱尺寸6m,点柱间距7m,顶柱厚3m时采场稳定性、技术性综合最优,在此基础上对采矿回采顺序进行优化,比较不同回采顺序方案随开采步骤应力、位移及塑性区的变化,结果得到从两翼向中央开采的顺序最优。(4)建立了宁都硫铁矿采场稳定性监测网络,分析研究了前期监测结果,验证了最优方案采场安全性。
[Abstract]:Ningdu Pyrite Mine is a gently inclined orebody, which is difficult to mine. At present, mining methods are not uniform, and the safety factor and recovery rate of stope are low. In order to realize high efficiency, safety and economic mining of mine, Rational selection of its mining method and optimization of its stope structural parameters have become the primary task of the mine at present. In this paper, the analytic hierarchy process (AHP) and fuzzy mathematics synthesis method are used to select the mining method, and the structural parameters and mining sequence of the mine are optimized by the methods of theoretical calculation and numerical analysis. The main conclusions are as follows: (1) the comprehensive evaluation model of the mining scheme of Ningdu pyrite is established by using the analytic hierarchy process (AHP) and the principle of fuzzy mathematics, and the optimum mining scheme is selected scientifically and reasonably. In the process of optimization, the influence factors of mining scheme are considered synthetically, the weight of each evaluation index is determined by analytic hierarchy process (AHP), and the alternative mining scheme is comprehensively evaluated according to the principle of fuzzy mathematics. The calculation results show that the Fangzhu mining method is the optimal mining method. (2) taking the safety factor as the evaluation index of pillar stability, the sensitivity ranking of the factors affecting pillar stability is carried out by using the orthogonal range theory. The maximum sensitivity of room span and pillar size is obtained, and the ultimate span of mine house is calculated by the empirical formula obtained from the conclusion of photoelastic test. On this basis, the critical pillar width is obtained by using the cusp catastrophe theory to establish the pillar instability model. In this paper, the thickness of roof column calculated by elastic mechanics method, structural mechanics method and material mechanics method under different span of mine house is integrated, and all the results are fitted and analyzed, and a formula suitable for the span of roof column and the thickness of roof column of Ningdu Pyrite Mine is deduced. Finally, the ultimate span of the mine house is 14.22m, the minimum pillar width is 3.99mm, and the top column thickness is 3m, which provides the basis for the numerical simulation of the subsequent stope. (3) different stope structural parameters are determined according to the field practice and theoretical calculation results. The orthogonal test method was used to design different schemes, and the ANSYS and FLAC3D software were used to simulate the different stope. The stress, displacement and plastic zone of different stope plans are compared, and the safety scheme is selected. The stress, displacement, plastic zone and recovery rate of the key parts of the stope are taken as the indexes to judge the superiority degree of each scheme, and the comprehensive evaluation model is established. The stability of the stope is obtained when the span of the building is 14 m, the size of the point column is 6 m, the spacing between the points and columns is 7 m, and the thickness of the top column is 3 m, and the technical synthesis is optimal. On this basis, the mining sequence is optimized. Comparing different mining sequence schemes with the change of mining step stress, displacement and plastic zone, the results show that the order of mining from two wings to the center is optimal. (4) the stope stability monitoring network of Ningdu Pyrite Mine is established. The preliminary monitoring results are analyzed and studied, and the safety of the optimal stope is verified.
【学位授予单位】：江西理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TD861.1

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