基于数值模拟正交试验的采空区稳定性因素的敏感性分析

Sensitivity analysis of stability factors of goaf based on numerical simulation orthogonal test

采空区稳定性受多种因素的制约,分析各因素的敏感性对确定复杂采空区失稳主控因素,为确定采空区稳定性综合评判体系构建过程中的权重具有十分重要的意义。本文通过综合分析,将单轴抗压强度、RQD、节理面间距、地下水、泊松比、采空区高度、采空区面积、采空区埋深、采空区长宽比等作为分析因素,基于正交设计和数值模拟方法确定“9因素4水平”实验方案,利用霍克布朗准则将采空区影响因素转化为岩石力学参数,以塑性区总体积、顶板塑性区体积、边壁塑性区体积为考核指标,对实验结果进行了极差分析,综合确定采空区埋深、采空区面积、单轴抗压强度、长宽比是对采空区稳定性影响最为敏感的四个因素,对采空区稳定性评估时影响因素权重的确定以及生产中设计矿房尺寸的确定具有指导意义。

The stability of goaf is restricted by variety of factors,determining the sensitivity of each influencing factor is very important for determining the unstable main control factors of complex goaf,and it is important for establishing the comprehensive evaluation system of goaf.Uniaxial compressive strength,RQD,joint spacing,groundwater,Poisson ratio,height of goaf,area of goaf,cover depth,length-width ratio of goaf are as analytical factors in the paper.Based on orthogonal design and numerical simulation method to determine“9 factors,4 levels”experiment schemes,the factors of rock mass are converting into rock mechanical parameters by the criterion of Hoek-Brown.The experimental results are analyzed with total volume of plastic zones,the volume of roof-plastic zone,the volume of side wall-plastic zone as an assessment indicators,it is show that the cover depth of goaf,the area of goaf,uniaxial compressive strength,and length-width ratio of goaf are the most sensitive to the stability of goaf.Which is theoretical guiding significance to the determination of the weight value of factors in stability assessment of goaf and designing stope size in production.