尾矿坝溃坝事故致因分析

尾矿设施是矿山生产要素的重要组成部分,同时也是潜在的危险源.伴随矿业工程的不断发展,尾矿坝事故屡有发生.尾矿坝溃坝事故不仅使尾矿流失,严重时还多破坏下游地区的生态环境,造成巨大的生命财产损失.文中列举了许多国内外重大的溃坝事故和溃坝所造成的损失,分析了溃坝原因,例如洪水漫顶、地震液化、渗流破坏等,提出了在生产中的预防措施.通过国内外的实例说明,希望引起大家对尾矿坝安全工作的重视.     

浅析国内外尾矿坝事故及原因

尾矿设施是矿山生产要素的重要组成部分,同时也是潜在的危险源。尾矿坝溃坝事故不仅使尾矿流失,严重时还多破坏下游地区的生态环境,造成巨大的生命财产损失。列举了许多国内外重大的溃坝事故和溃坝所造成的损失,分析了溃坝原因,提出了在生产中应吸取的教训及预防措施。通过国内外的实例说明,希望引起大家对尾矿坝安全工作的重视。     

国外尾矿坝事故调查分析

尾矿设施是矿山生产要素的重要组成部分,同时也是潜在的危险源.伴随矿业工程的不断发展,尾矿坝事故屡有发生.尾矿坝溃坝事故不仅使尾矿流失,严重时还多破坏下游地区的生态环境,造成巨大的生命财产损失.通过调查1960年以来国外发生的较典型的80例尾矿坝事故,对事故发生的时间特征、地点分布特征、在不同矿山发生的频率特征进行了对比分析.从事故发生的特点看,许多溃坝事故发生在暴雨过后的短暂时间内.尾矿坝事故与地震的破坏作用和其他10种因素有关,而由于暴雨和地震原因产生的事故占40%以上.如果尾矿库位于河流附近,其地面坡度较大时,溃坝会使流体状态的尾矿以(8～40)km/h的速度向下游排泄,污染范围多达160 km.对地基强度不足、地震液化、库水位上升、渗流等不同作用机制下发生坝体破坏的主要模式进行了讨论.     

我国尾矿坝溃坝事故成因及生态环境影响评价

在典型尾矿坝溃坝事故调查的基础上,对尾矿坝事故发生机理进行了分析,其中包括规划、设计、施工、洪水破坏、漫顶渗流、地震的破坏等。其次,研究了尾矿坝失事对生态环境造成的影响,包括水资源系统污染、土壤污染、水土流失等。最后提出了防止尾矿坝破坏,确保尾矿坝安全运行的对策措施。研究成果对尾矿坝安全监管部门和尾矿坝安全管理工作具有一定的参考价值。     

尾矿库溃坝模式分析及风险指标体系的研究

在总结国内外尾矿库事故特点的基础上,系统研究了尾矿坝的溃坝模式,并基于尾矿坝指标的工程性质分析和相关性分析,研究并建立了尾矿库溃坝风险指标体系。该体系的建立为尾矿坝溃坝风险评判模型及评判方法的研究提供前提条件,可为尾矿库运行期的安全监管提供依据。     

金属矿山尾矿坝的溃坝事故及其他有关情况简介

尾矿坝的安全管理对矿山的正常生产和人民生命财产的安全都是至关重要的,应当引起足够的重视。文中列举了许多国内外重大的溃坝事故和溃坝所造成的损失,分析了溃坝原因,强调了尾矿坝的稳定性监测工作的重要性。通过国内外的实例说明,若能解决好坝体和坝基的渗流问题,尾矿坝高筑是完全可行的。     

尾矿坝沉降观测资料的分析方法

国内大多数尾矿坝都是采用上游法筑坝,上游法筑坝与下游法筑坝相比,筑坝工艺简单、经济,但其稳定性不如下游法。随着冶金工业的发展,我国尾矿坝技术也有了很大改进。但目前有不少矿山的尾矿坝都相继进入中晚期,尾矿坝逐年增高,其安全稳定性也变得越来越重要。特别是近几年来,少数矿山的尾矿坝发生了溃坝事故,如1985年东波铅锌矿尾矿库和山西塔儿山铁矿尾矿库溃坝,1986年黄梅山铁矿尾矿库溃坝等都带来严重危害和损失,因而这一问题已引起了各矿山的重视。为     

尾矿库溃坝事故树分析

近年来,我国尾矿库事故时有发生,给人民生命财产造成了极大威胁。本文针对尾矿库溃坝事故,建立了尾矿坝溃坝的事故树,求出了最小割集合和最小径集合,并提出了控制措施,从而为进行尾矿坝的安全评价奠定了基础。     

尾矿库溃坝有关问题探讨

通过对国内部分尾矿库溃坝事件进行分析,结合尾矿坝的实际情况,深入分析溃坝的具体原因和机理,探讨了适合尾矿库溃坝的水力计算方法和对下游危害程度等问题,从而有利于对溃坝事故进行科学的防范。     

矿山尾矿库事故预防措施探讨

通过对我国山西省临汾市襄汾县发生的尾矿坝特大溃坝事故的原因分析入手,分别从尾矿库选址,坝的选型、设计、施工以及尾矿库的运营及维护等方面阐述了尾矿库事故预防的相关措施,以期对减少尾矿库事故的再次发生提供一些帮助。     

强降雨条件下某铅锌矿尾矿堆积坝安全稳定性分析

强降雨是影响尾矿坝安全的重要因素之一,同时尾矿堆积坝在建造的过程中随着选矿工艺的改变堆坝尾砂的粒径分布也随之变化。为了研究不同组构尾矿堆积坝在强降雨条件下的稳定性,以湖南某铅锌矿尾矿堆积坝为研究对象,在分析该尾砂坝各级堆积子坝的尾矿砂物理力学性质的基础上,采用数值模拟方法研究了该尾矿坝在强降雨作用下不同时期堆积子坝的稳定性。研究表明:1)不同高度堆积子坝的尾砂组构不同,其不均匀系数、曲率系数以及黏聚力不同,尾矿堆积坝的安全系数与尾砂黏聚力呈正相关关系,与尾砂的不均匀系数呈正比,与曲率系数呈反比;2)相同降雨强度,降雨时长的增加对尾矿堆积坝整体稳定性影响小,但对坝坡表面及一定深度的尾砂有影响,其负孔隙水压力减小,坝体松散,影响坝坡稳定;3)尾矿堆积坝各部位能承受的最大剪应变与尾砂的黏聚力呈正相关关系,且黏聚力大的坝体的最大剪应变在各个区域都较黏聚力小的坝体有较大剪应变。实际堆积坝施工过程中可通过尾砂组构来分析坝体在强降雨作用下的稳定性。     

Criteria for Identifying the Major Risks Associated with Tailings Ponds in Romania

Damage caused by accidents at hydraulic structures, due to natural hazards or human causes (e.g. terrorist sabotage) can be comparable to those caused by natural disasters. The paper identifies the major advantages of a common methodology for risk identification and quantification regarding the potential impact of accidents at tailings dams on the environment. Relevant Romanian and EU legislation and regulations enacted following the “Baia Mare” accident in 2000 are reviewed, along with a common risk evaluation methodology that can be applied by the mining sector to tailings dams.     

我国尾矿库事故次生河流污染的特征分析

2000年以来，我国发生了多起尾矿库事故次生河流污染事件，造成了严重的环境污染。为了有效应对尾矿库事故对河流的污染，保障供水安全，通过对国内40起事故的综合分析，主要成因为违规建设运行、暴雨和地震等自然灾害、排洪和溢流等管道破裂，并具有污染物排放量大、污染严重、污染因子多、应急处置难等特征。研究表明，构筑多级拦截坝和合理利用各种环境应急空间是次生河流污染事件最有效的应急处置措施。对于拦截的污水，应根据污染物的种类和性质分别采取混凝沉淀、吸附、氧化还原等方法减低污染物的浓度和毒性，最终恢复河流正常状态。     

Numerical Study of the Effects of Drainage Systems on Saturated/Unsaturated Seepage and Stability of Tailings Dams

The stability of tailings dams is affected by seepage characteristics such as the location of the phreatic surface inside the dam, the effects of the capillary fringe, and the unsaturated zone above the zero pore pressure level. In this study, the performance of drainage systems in tailings dams was investigated by analyzing saturated and unsaturated seepage in the dam, considering the effects of the construction method, tailings properties, and the type of drainage systems. First, general seepage characteristics in tailings dams were studied and the effects of non-homogeneity were investigated. Our results show that in a silty tailings dam with a height of 15 m, unsaturated plus capillary seepage flux can reach 13% of the total seepage. The total head vs. discharge volume curves under various conditions were compared and their practical implications are presented. Then, stability analyses were carried out using the results of seepage analyses for different construction methods, material properties, and drainage systems. Finally, a number of practical conclusions are drawn regarding dam stability and the efficiency of toe, blanket, and chimney drains in different construction methods. Using a blanket and/or a chimney drain can increase the stability safety factor by up to two times, depending on the type of material.     

Effects of Nonhomogenity of Permeability on Tailings Dams

This paper has the objective of showing the influence of the permeability gradient during the construction of tailings dams, built by the upstream method, using the hydraulic fill technique. During the hydraulic disposition, two mechanisms affect the tailings permeability: the hydraulic segregation and the consolidation due the staged construction procedure. These mechanisms influence considerably the permeability distribution along the fill and, consequently, the behaviour of the dam. Results show that the pore pressure immediately after deposition may reach quite high values (532 kPa), but dissipates in a short period of time (1 to 10 days). Then, this effect should be taken into account in a short-term stability analysis of tailings dams. On the other hand, after pore pressure dissipation, there is a gain in the shear strength (13 %), which should also be considered, but in a long-term stability analysis of tailings dams.     

细粒尾矿堆积坝的地震稳定性分析

在分析地震对尾矿坝造成破坏特点的基础上，介绍了尾矿坝地震稳定性分析方法。以龙都尾矿库细粒尾矿堆积坝为例，分析了在当地发生七级地震情况下，尾矿坝在不同状态下的结果，为矿山进行尾矿库的安全管理提供了科学依据。     

陕西省尾矿库遥感调查与环境影响分析

利用SPOT-5、RAPIDEYE等卫星遥感数据对尾矿库识别方法进行研究,调查出陕西省尾矿库分布现状,并对其存在环境问题进行分析。陕西省截止到2012年有尾矿库270座,集中分布于陕南秦巴山区,类型以铅锌矿、铁矿和钼矿等为主;尾矿库对环境的影响表现为占用大量土地,所含的有害成分对河流水体产生污染,部分病库、危库存在泥石流隐患。     

Effect of seepage control on stability of a tailings dam during its staged construction with a stepwise-coupled hydro-mechanical model

Seepage flow renders tailings dams vulnerable to failure during their staged construction. Draining is one of the most effective measures in improving dam stability. In this study, a stepwise-coupled hydro-mechanical model is employed to examine the effect of seepage control on the stability of a tailings dam during its staged construction. The settlement and deformation of the tailings under gravity load are modelled using the Duncan–Chang non-linear elastic E–B model, and the seepage flow through the tailings with drains is characterised by a variational inequality formulation of Signorini’s condition. The Kozeny–Carman equation is calibrated to illustrate the dependence of hydraulic conductivity on the porosity and volumetric deformation of the tailings. The proposed model was applied to assess the performance of the drains designed for the Luogou tailings disposal in Luanchuan County, Henan Province, China. Numerical results show that the stress-induced variation in tailings permeability could be of 1–2 orders of magnitude, and a proper design of the drainage system is of great importance in lowering the phreatic surface and protecting the tailings from seepage erosion.     

Reinforced terraced fields method for fine tailings disposal

New mining technologies can exploit low-grade ores but they produce high volumes of waste, such as tailings. Further, current mineral processing techniques produce more and more fine tailings. How to dispose of these tailings is a key issue in the sustainable operation of a mine. A traditional method is to construct a settling or tailings pond for storage. Such a method requires sufficient coarse particles to raise a dam or embankment. However, the fine tailings contain little coarse particles and have poor mechanical properties. The stability of a tailings dam thus becomes a major issue if the traditional method is used. According to statistical data, all fine tailings dams or ponds in China have failed or have failure potential. Therefore, fine tailings disposal is a challenge to mine operators and new disposal methods should be explored for the stability improvement of tailings dams. In this paper, an innovative method of reinforced terraced fields is presented to satisfy the specific requirement of fine tailings disposal. By using an actual mine, this paper reports in detail the design concept and procedures for this method. Its feasibility is evaluated and its fundamental are analyzed.