摘要
南芬露天矿面临频繁的滑坡、泥石流、崩塌、沉降等地质灾害问题。为了揭示露天矿滑坡机理,并充分理解其动力学过程,以2019年1月4日发生在南芬露天矿下盘394~502m台阶中部老滑坡体区域的滑坡为例进行研究。该工作结合现场勘查、地质资料和数值模拟等手段,对露天矿滑坡进行分析。研究结果表明,开挖扰动、冻融循环,爆破振动是诱发露天矿滑坡的主要原因。另外,滑坡区域位于老滑坡体区域内,滑坡源属于松散堆积物,老滑坡体自身的低稳定性是发生滑坡的另一个重要因素。采用光滑粒子流体动力学方法(SPH)结合弹塑性Mohr-Coulomb理论对露天矿滑坡的动态全过程进行了数值模拟。数值结果表明,露天矿滑坡堆积体分布在垂直落差约120m高的台阶上,滑坡形态呈现倒V字形,滑坡体下缘宽度约240m。露天矿滑坡形态、滑动距离、范围等与现场调查结果吻合较好。SPH方法可以很好地再现露天矿滑坡的动态过程。数值结果可以为划定露天矿危险区域,制定防灾减灾措施提供依据。
Nanfen open-pit mine faces frequent landslides,debris flows,collapses,subsidence,and other geological disasters.In order to reveal the mechanism of the open-pit mine landslide and have a full understanding of its dynamic process,the landslide that occurred in the middle of the 394-502 m steps of the Nanfen open-pit mine on January 4,2019,is taken as an example to study.In this work,on-site surveys,geological data,and numerical simulation are combined to study the open-pit mine landslides.The results show that excavation disturbance,freeze-thaw cycles,and blasting vibration are the main reasons to trigger the landslide of the open-pit mine.In addition,the landslide area is located in the area of the old landslide body,and the source of the landslide is composed of loose geomaterials.The low stability of the old landslide body itself is another important factor for the occurrence of the landslides.The smoothed particle hydrodynamics(SPH)method combined with the elastoplastic Mohr-Coulomb theory is used to simulate the whole dynamic process of the open-pit mine landslide.Numerical results show that the accumulation bodies of the open-pit mine landslide are distributed on the steps with a vertical drop of about 120 m.The landslide shape presents an inverted V shape,and the width of the lower edge of the landslide body is about 240 m.The shape,sliding distance,and scope of the open-pit mine landslide are in good agreement with the field survey results.The SPH method can reproduce the dynamic process of the open-pit mine landslide well.The numerical results can provide a basis for delimiting the dangerous areas of open-pit mines and formulating disaster prevention and mitigation measures.
作者
王长军
曹春晖
陶志刚
WANG Changjun;CAO Chunhui;TAO Zhigang(Waitoushan Iron Mine,Bengang Group Corporation,Benxi 117005,China;State Key Laboratory for Deep Geomechanics and Underground Engineering,Beijing 100083,China;School of Mechanics and Civil Engineering,China University of Mining and Technology(Beijing),Beijing 100083,China)
出处
《中国矿业》
2021年第7期107-114,共8页
China Mining Magazine
基金
越崎学者专项资金资助(编号:800015Z1207)
中央高校科研业务费资助(编号:2015QB02)。
关键词
露天矿
滑坡机理
动力学过程
光滑粒子流体动力学
open-pit mine
landslide mechanism
dynamic process
smoothed particle hydrodynamics
