采动影响下露天矿滑坡失稳变形数值模拟研究  

Numerical Simulation Study on Deformation and Instability of Landslides in Open-Pit Mines under Mining-Induced Influences

作　　者：王嘉 董强 郑佳男 陶志刚 WANG Jia;DONG Qiang;Zheng Jianan;TAO Zhigang(Nanfen Open-pit Mine of Bensteel Mining Company,Benxi 117014,China;State Key Laboratory for Tunnel Engineering,Beijing 100083,China)

机构地区：[1]本钢矿业公司南芬露天铁矿,辽宁本溪117014 [2]隧道工程灾变防控与智能建养全国重点实验室,北京100083

出　　处：《矿业工程》2024年第6期75-81,共7页Mining Engineering

摘　　要：露天矿经历多次开采作业后,受地质特性影响形成了大范围滑坡,对矿场的安全开采构成了严重威胁。以南芬露天矿下盘滑坡为例,探究采动影响下老滑坡的变形失稳机理。首先,基于现场勘察成果,调查了滑坡特征及演变次序,进一步构建边坡三维地质模型,并利用COMSOL和MATLAB联合仿真方法探究采动影响下露天矿滑坡演变全过程。结果表明:老滑坡导致滑坡区南下侧临空,失去支撑,引发边坡变形不断向北侧扩展并累积,直至使得原本临近极限状态的潜在滑面贯通,形成整体滑移;结合模拟所得的损伤区、位移趋势,滑坡区结构面产生不同程度的活化,演化过程与损伤区具有一定的同步性,与实际观测的位移场相符;分析滑坡变形机理,揭示了南芬露天矿滑坡在采动作用下,老滑坡从缓慢蠕变状态进入加速变形状态,最终导致滑坡区再次变形失稳。Repeated mining operations in open-pit mines have led to the formation of extensive old landslides,posing a serious threat to the safe extraction of minerals.Taking the footwall landslide of the Nanfen open-pit mine as an example,this paper explores the deformation and instability mechanisms of old landslides under mining-induced influences.First,based on field survey results,the characteristics and evolution sequence of the landslide are investigated,and a three-dimensional geological model of the slope is constructed.The joint simulation method of COMSOL and MATLAB is used to explore the entire evolution process of the landslide under mining influences.The results show that old landslides cause the southern side of the landslide area to become empty and lose support,triggering deformation of the slope that progressively extends and accumulates northward.This process continues until the potential slip surface,which was initially near its limit state,becomes continuous,resulting in overall sliding.The simulation results,combined with observed damage zones and displacement trends,indicate varying degrees of activation in the structural planes within the landslide area.The evolution process shows a certain synchronicity with the damage zones,consistent with the observed displacement field.Analysis of the deformation mechanism reveals that,under mining activities,the old landslide at the Nanfen open-pit mine transitions from a slow creeping state to an accelerated deformation state,ultimately leading to the re-deformation and instability of the old landslide area.

关 键 词：南芬露天矿 滑坡 数值模拟 变形机理 稳定性 

分 类 号：TD854[矿业工程—金属矿开采]