摘要
以焦家金矿为工程背景,首先基于非接触扫描系统及方法得到矿区优势节理组,然后综合理论分析、数值模拟及现场监测的手段,对深部巷道掘进过程中围岩应力演化规律进行分析,并进行多因素敏感性分析。结果表明,矿区中共存在4组优势节理组,采用块体理论得到7种块体对围岩稳定性的影响规律,不同块体形式及位置对围岩稳定性影响程度差距较大,考虑节理组合劣化效应提出修正的M-RMR分级法,现场应用表明矿区围岩稳定性主要为Ⅳ级,少量为Ⅲ级和V级;基于Hoke-Brown准则计算得到不同围岩等级的力学参数;在此基础上,采用3DEC离散元软件和DFN技术,并结合压力拱理论进行数值模拟分析,结果表明,随着推进距离的增加,顶板、两帮及底板压力拱均逐渐向岩体深部转移,顶板压力拱内外边界均明显大于两帮,且波动更剧烈。敏感性分析结果表明,开采深度对压力拱的空间形态没有明显的影响,而稳定性级别则对压力拱的形态及成拱系数有明显的影响。本文的研究成果可为深部金属矿生产的地压分析及控制提供理论依据。
With Jiaojia Gold Mine as the engineering background,firstly,the dominant joint groups in the mining area have been obtained with non-contact scanning system and its method.Then,the stress evolution law of surrounding rock in the process of deep roadway excavation has been analyzed through theoretical analysis,numerical simulation and on-site monitoring,and multi-factor sensitivity analysis has been carried out.The results have shown that there are four groups of dominant joint groups in the mining area.Seven kinds of blocks have influence on the stability of surrounding rock by using block theory.Different block types and locations have great difference in the degree of influence on the stability of surrounding rock.Considering the deterioration effect of joint combination,a modified M-RMR classification method has been proposed.Field application has shown that the stability of surrounding rock in the mining area is mainly Ⅳ grade,a small number of whom are Ⅲ grade and V grade.Based on Hoke-Brown criterion,the mechanical parameters of different surrounding rock grades have been calculated.On this basis,the numerical simulation analysis has been carried out with 3DEC discrete element software and DFN technology,and combining with the theory of pressure arch.The results have shown that with the increase of advancing distance,the pressure arch of roof,two sides and floor gradually transfers to the deep part of rock mass,and the internal and external boundaries of the pressure arch of roof are obviously larger than those of the two sides,and the fluctuation becomes more intense.The sensitivity analysis results have shown that the mining depth has no obvious influence on the spatial shape of pressure arch,while the stability level has obvious influence on the shape and arch forming coefficient of pressure arch.The research findings in this paper can provide theoretical basis for pressure analysis in deep metal mining.
作者
戚伟
付建新
李腾
QI Wei;FU Jianxin;LI Teng(School of Civil and Resource Engineering,University of Science and Technology Beijing,Beijing 100083,China;State Key Laboratory of High-Efficient Mining and Safety of Metal Mines,Ministry of Education,University of Science and Technology Beijing,Beijing 100083,China)
出处
《采矿与安全工程学报》
EI
CSCD
北大核心
2020年第2期327-337,共11页
Journal of Mining & Safety Engineering
基金
国家自然科学基金青年科学基金项目(51804016)。
关键词
节理组合
围岩分级
三维离散元分析
压力拱
敏感性分析
joint combination
surrounding rock classification
three-dimensional discrete element analysis
pressure arch
sensitivity analysis
