落矿冲击作用下矿柱结构参数优化与稳定性分析

Stability analysis and structural parameter optimization of pillar under impact of rockfall

应用理论计算和ABAQUS数值模拟软件对6种桃形矿柱稳定性进行分析。首先,将开采中段划分为4个盘区进行开采;其次,基于结构力学模型,分析6种桃形矿柱参数对巷道在最大冲击力下的最小保护层厚度变化的影响;最后,对桃形矿柱在冲击作用下的巷道残余完整长度与垂高分别进行筛选,并选择桃形矿柱最佳设计方案。研究结果表明:在回采过程中,开采中段顶板受力状态由压应力变为拉应力,间柱压力增大,但顶板和间柱均稳定,未达到破坏强度;桃形矿柱坡度越大,保护层厚度越小;在冲击载荷作用下,坡度越小的桃形矿柱受破坏程度越小,高度越大的矿柱变形能越大;桃形矿柱坡角为60°、总高为15 m的方案为最佳设计方案。

Stability analysis of six different types of peach-shaped pillars were carried out using methods of theoretical calculations and the ABAQUS numerical simulation software.First,the stage of mining was divided into four panels during the mining process.Second,the influences of six kinds of parameters of peach pillars on the minimum protective layer thickness under the maximum impact force of the roadway were analyzed based on structural mechanics model.Finally,the residual full length and vertical height of the roadway under the impact of the peach-shaped pillars were screened,and the optimal design scheme was chosen for the peach-shaped pillars.The results show that during the mining process,the stress state of the roof is changed from compressive stress to tensile stress,and the inter-pillar pressure increases,but the top plate and pillar are both stable and do not reach the breaking strength.It is found that the larger the slope is,the thinner the thickness of the protective layer is.With the action of impact loads,the damage degree is smaller for peach-shaped pillar with smaller slope,and the deformation energy is greater for peach-shaped pillar with higher height.When the slope angle is 60°and the length is 15 m,the design scheme proves to be the best.