摘要
受锦屏磷矿开采的影响,磷矿东北侧的将军崖岩画区岩体出现严重开裂现象.为研究磷矿开采过程对将军崖岩画区岩体开裂的影响,以锦屏西山磷矿层及将军崖岩画区的地质体为研究区域,通过离散元软件3DEC建立了研究区的数值模型,并对磷矿开挖过程中研究区岩体的变形与破坏过程进行了模拟.结果表明:磷矿开采过程中,拉应力区首先出现在采空区顶板边界处,随着采空区深度的增加,拉应力区逐渐向采空区顶板后方延伸拓展,且穿过岩画区后继续向后方扩展,同时在顶板坡脚处的岩体因受到剪切作用出现塑性变形.随着采空区深度的增加,后缘拉张破坏面向深处发展,顶板坡脚剪切破坏面则逐渐向上发展,最终导致将军崖岩画区岩体出现开裂.此外,使用离散元软件3DEC模拟了岩石蠕变作用下20年后将军崖岩画区岩体的开裂情况.结果显示,20年后将军崖岩画区岩体的各监测点位移和东西边界位移差均呈增大趋势,说明20年后将军崖岩画区岩体的开裂速度将会加快.
Affected by the mining of Jinping Phosphate Mine,the rock mass in rock painting area of Jiangjun Cliff located in the northeast of phosphate mine has serious cracking.In order to study the influence of phosphate rock mining process on rock mass cracking in rock painting area of Jiangjun Cliff,with the West Mountain phosphate rock layer of Jinping and the geological body of Jiangjun Cliff rock painting area as study areas,the numerical model of the research area is established through the discrete element software 3DEC,and the deformation and failure process of rock mass in the study area during phosphate rock excavation is simulated.The results show that in the process of phosphate mining,the tensile stress area first appears at the roof boundary of the goaf.With the increase of the depth of the goaf,the tensile stress area gradually extends to the rear of the roof of the goaf,and continues to expand to the rear after passing through the rock painting area.At the same time,the rock mass at the foot of the roof slope appears plastic deformation due to shear.With the increase of the depth of the goaf,the tensile failure of the trailing edge develops towards the depth,and the shear failure surface of the roof slope toe gradually develops upward,which eventually leads to the cracking of the rock mass in the rock painting area of Jiangjun Cliff.In addition,the discrete element software 3DEC is used to simulate the cracking of the rock mass in rock painting area of Jiangjun Cliff after 20 years under the action of rock creep.The results show that the displacement of each monitoring point and the displacement difference between the East and West boundaries of the rock mass in rock painting area of Jiangjun Cliff increase after 20 years,indicating that the cracking speed of the rock mass in rock painting area of Jiangjun Cliff would accelerate after 20 years.
作者
李伟
理继红
何伟
李明
常学文
LI Wei;LI Jihong;HE Wei;LI Ming;CHANG Xuewen(Geological Survey of Jiangsu Province,Nanjing 210018,China;School of Earth Sciences and Engineering,Hohai University,Nanjing 211100,China)
出处
《河南科学》
2021年第10期1624-1631,共8页
Henan Science
基金
国家自然科学基金(41672258)
江苏省国土厅科技计划项目(2018045)。
关键词
磷矿开挖
岩体开裂
倾倒变形
数值模拟
phosphate rock excavation
rock cracking
toppling deformation
numerical simulation
