主成分分析法在露天煤矿岩石质量评价中的应用

为了研究别矿不同平盘岩石的物理力学性质对爆后大块率和根底率的影响,以别矿1264-1252东坡道,1252-1240双坡道和1228平盘东为试验对象,对其岩石进行取样并测定其物理力学参数,运用主成分分析法分别对岩石的密度、单轴抗压强度、抗拉强度、弹性模量和泊松比5项指标进行评价和分析,建立岩石质量评价的数学模型。利用该模型对不同水平台阶的岩石质量进行分析评价。结果显示:在1264-1252东坡道位置,岩石的硬度较大,不易破碎,这与实际的工程情况和矿区的实际情况一致。针对1264-1252东坡道的爆破参数进行优化,孔深为13.5m,孔网参数为3.5m×6.5m,最小抵抗线为2.5m,装药结构为中部空气间隔装药且空气间隔装药比例为15%时,大大地降低了大块率和根底率,获得了良好的爆破效果。

Application of Principal Component Analysis on Rock Quality Evaluation in Open-pit Coal Mine

In order to study the influence of the physical and mechanical properties of different flat plate rocks on the boulder yield and the root rate after blasting,1264-1252 East ramp,1252-1240 double ramp and 1228 flat plate east of BieMine were taken into the tests.The physical and mechanical parameters of the rock samples were evaluated and analysed by principal component analysis,including the rock density,uniaxial compressive strength,tensile strength,modulus of elasticity and Poisson′s ratio.Then the mathematical model of rock quality evaluation was established.The model was used to analyse and evaluate the rock quality of different horizontal benches.The results showed that the hardness of the rock at the position of 1264-1252 eastern ramp was relatively high and it was not easy to break,which was consistent with the actual engineering situation and the actual situation of the mining area.The blasting scheme of 1264-1252 east ramp was optimized.The spacing was 6.5 m,the row distance was 3.5 m,and the burden was 2.5 m.When the charge structure was middle air-decked charge and the air-drecked charge proportion was 15 %,the boulder yield and the root rate were greatly reduced,and favourable blasting effect was obtained.