露天矿崩落法处理复杂空区后的安全评估方法

露天矿崩落法处理大型复杂空区后需进行安全分析。结合某露天矿多年采空区治理的实践,提出了待评估区的分区原则,分区内已处理空区塌实程度的分析方法,分析了下部空区稳定性的主要影响因素,制定了半定量的崩落法处理空区后的安全评估标准,该标准以处理空区塌实程度、下部空区稳定性影响因素、虚渣厚度等指标为基础,共有19种不同情况的指标组合,对应着安全、相对安全、相对危险、危险、极危险等五大类危险程度。结合空区实例,应用新提出的安全评估方法对处理后的E区1334复杂空区进行危险程度评估,该爆区共分为49个分区,从塌实程度分析,41个分区塌实或基本塌实,4个分区局部未塌实,4个分区未完全塌落;从危险程度评估,该爆区共有16个安全分区、4个相对安全分区、3个相对危险分区、14个危险分区、12个极危险分区;不同的充填图案分别代表充填爆区内每个分区的危险程度,可直观显示不同区域的危险程度和范围;安全评估可为后期资源的安全回收提供可靠的依据,E区1334爆区已累计成功回收矿石量300万t。

Safety evaluation method of goaf treatment with caving method in the open pit mine

According to the requirement of safety analysis after the large complex goaf treatment in open pit mine, this paper puts forward the partition principles and analytical method on collapse extent of caving goafs, combing with years of goaf treatments in an open pit mine, analyzes the key factors of the lower goaf stability, draws up semi-quantity safety evaluative standard on the basis of collapse extent of caving goafs, key factors of the lower goaf stability and thickness of the top broken rock, this standard includes 5 types of dangerous levels which are safety, relative safety, relative danger, danger and extreme danger, 5 dangerous levels are corresponding with 19 different circumstances. It evaluates the dangerous levels of the whole blasting area with the new evaluation method after caving complex goafs in section E 1334, the whole area to be assessed is partitioned to 49 smaller partitions. 41 smaller partitions have completely collapsed, 4 smaller partitions have not been full filled, other partitions have not completely collapsed based on collapse extent analysis. There are 16 safe partitions, 4 relative safe partitions, 3 relative-danger partitions,14 dangerous partitions and 12 extreme dangerous partitions based on risk assessment, fill different partitions with different patterns which respectively signify safe and relative safe, relative dangerous, dangerous, and extreme dangerous. This filling chart directly shows the different dangerous extents and ranges. Safety evaluation could provide foundation for reclaiming ore resources around goafs, the open pit mine have accumulatively reclaimed ore resources 3,000,000 tons in the area of section E 1334.