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

采空区稳定性受多种因素的制约,确定各影响因素的敏感性,对确定复杂采空区失稳主控因素,为采空区稳定性综合评判体系构建过程中权重确定具有十分重要意义。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、采空区的长宽比作为分析因素。基于正交设计和数值模拟方法确定9因素4水实验方案,利用霍克布朗准则将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4个因素是对空区稳定性影响最为敏感,对采空区稳定性评估时影响因素权重确定以及生产中设计矿房尺寸,具有理论指导意义。

Sensitivity Analysis of Stability Factors of Goaf Based on Numerical Simulation Orthogonal Test

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 L₃₂(4^₉) experiment schemes, The factors of rock mass are converting into rock mechanical parameters by the criterion of Hoek-Brown. the experimental results were 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 shown 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 goag and designing stope size in production.