大型尾矿坝加高过程三维渗流分析

采用三维有限元渗流和稳定性分析相结合的方法,对大型尾矿坝加高过程进行稳定性评价。分析结果表明:现状坝体的浸润线高度和渗流路线正常,稳定性系数满足要求,但安全储备量不大;加高坝体时浸润线高度变动不大,排渗设施对降低浸润线有重要作用。当坝高加高到100m坝高时,坝坡抗滑稳定安全系数稍小于规范值,继续增加坝高导致坝坡抗滑稳定系数与规定值差距较大,不满足规范要求。通过数值计算确定了尾矿坝加高限值为100m,并给出填筑过程的建议措施。     

基于渗流与应力耦合的尾矿坝稳定性分析

针对尾矿库坝体加高影响其稳定性的问题,基于有限差分法采用渗流与应力耦合模型,对某尾矿坝在4种不同工况下进行渗流场和静力场分析。渗流场计算结果表明:加高坝体在洪水位工况下,坝体内自由面比现状坝洪水位工况升高很多,浸润线最小埋深为5.88 m,小于规范规定的最小埋置深度6~8m,加高坝体在洪水位工况是不安全的,需采取加固措施。应力场计算结果表明:加高坝体洪水位工况下,初期坝坝脚外坡处应力水平值为0.8,坝坡靠近堆积坝坝顶处应力水平值为0.75,应力水平过大,需采取加固和排渗措施,分析结果与渗流场分析结果一致。     

满山红尾矿坝加高扩容渗流稳定性分析

尾矿坝是堆存金属非金属等矿山选矿废弃物的构筑物,其数量及坝体高度随国家对矿产资源的巨大需求而快速增加。验算了尾矿坝现状和最终堆积标高两种情况下相应的最不利剖面位置进行渗流计算和静力稳定计算。同时,运用二维有限元计算坡面浸润线,采用极限平衡法对坝体现状和加高扩容后的稳定安全系数进行分析。计算结果表明,坝体最终堆积标高剖面的稳定安全系数在不同计算条件下均满足规范要求,说明堆积坝加高扩容方案是安全可靠的。     

学峰尾矿库坝体稳定性研究

坝体边坡稳定性是尾矿库安全的重要因素。在坝体稳定性研究中,首先须考虑地下水渗流的作用,明确尾矿坝浸润线埋深特点;后根据勘察资料,进行稳定性计算,以验证坝体稳定性安全系数的规范符合性。研究结果表明:在排渗结构功能正常的工况下,坝体无论在正常运行、洪水运行和特殊运行条件下,坝体抗滑稳定安全系数都能满足规范要求。     

富贵鸟1号尾矿库坝体稳定性数值模拟

基于富贵鸟1号尾矿库现有岩土工程地质条件,采用有限元法对该尾矿坝进行渗流稳定性及静力有限元数值模拟分析.结果表明坝体在正常运行工况以及洪水运行工况下,尾矿堆积坝坝坡浸润线埋深满足规范规定.坝体浸润线沿初期坝坝坡出逸,系透水堆石坝正常排水现象,不会对坝坡产生如管涌、流沙和表面沼泽化等渗流破坏.并在此基础上,采用毕肖普法和瑞典圆弧法对坝体进行正常水位工况、洪水位工况和洪水位及地震作用工况下的稳定性计算,得到尾矿坝坝体内部应力应变关系,以及坝体最小稳定性系数.结果表明坝体的稳定性系数大于规范要求的最细小安全系数,坝体是安全稳固的.     

降雨条件下尾矿库稳定性计算分析

通过相关物理力学试验,分析了尾砂的物理力学性质,用Geo-Studio有限元软件计算和分析降雨条件下尾矿坝的浸润线。通过Slide软件,用极限平衡法中的简化Bishop法和瑞典法对降雨条件下尾矿坝的稳定性进行分析。结果表明,尾矿坝在现状高程下,其坝体在正常运行、洪水运行和饱和运行工况时计算的安全系数均能满足规范要求,计算得到的稳定性滑面大多是经过坝体最底部的深度滑弧面,且滑弧面范围较大。     

尾矿库抗震液化及震后稳定性分析

通过对御驾泉尾矿库在地震作用下的动力反应及液化分析,比较345 m和370 m筑坝两种工况,得出坝体在特征地震波作用下,动力反应不显著,只在水面区域变形稍大,坝体形态较完好。地震产生的超孔隙水压力的消散总是在地震结束后,采用瑞典法和简化毕肖普法分析表明,震后坝内安全系数变化不大,均满足规范要求。为保证坝体安全应加强坝内浸润线观测,当浸润线埋深小于6m时,应及时采取工程措施。     

鑫洲铁矿尾矿坝稳定性分析

对中国黄金集团迁西鑫峪矿业鑫洲铁选场尾矿库进行了系统的稳定性评价,采用数值方法对渗流安全性能和坝体稳定性进行计算,结果表明:尾矿库浸润线最小埋深大于规程要求的深度,满足规程规定。初期坝体、终期坝体及副坝在各种工况条件下安全系数均高于规定要求,计算得出的抗滑稳定系数大于允许最小安全系数,能保证尾矿坝的稳定运行。     

基于Geo-studio的尾矿库加高扩容后坝体稳定性分析

加高已有尾矿坝是扩大尾矿库库容的一种经济可行的办法,但尾矿库等级升高,溃坝风险增大。以辽宁某尾矿库为例,通过现场勘查和室内试验获得堆积层基本物理力学参数;对比实测浸润线,利用Geo-studio软件模拟分析尾矿坝加高前后渗流场并优化渗透系数,进一步分析坝体静力稳定性和地震动力响应。结果表明：尾矿库浸润线最小埋深在10 m以上,符合规程要求;采用瑞典圆弧法和简化Bishop法计算的安全系数均高于允许最小安全系数,地震对坝体安全性影响较小,只有局部液化;加高后最危险滑面位于初期坝附近370 m标高以下,主要为深层圆弧形滑移,原因是尾粉土渗透性较低导致浸润线升高,建议实时监测尤其是洪水期浸润线高度,必要时采取相应措施降低浸润线,有效杜绝渗透破坏。     

金属矿山高速率筑坝尾矿库稳定性分析

以四川省攀枝花市虹亦钒钛磁铁矿五道沟尾矿库为例,利用无人机摄影测量技术采集数据,建立三维模型,计算其筑坝速率。在此基础上,利用DEM及点云剖面进行表观变形分析,然后利用渗流场模拟计算浸润线分布情况,最后采用极限平衡法耦合分析坝体稳定性。分析结果表明:五道沟尾矿库筑坝速率为24.89 m/a,属高速率筑坝;2期坝体DEM及点云剖面数据基本重合,变形甚微;浸润线埋深明显大于规范要求;采用简化毕肖普法和瑞典圆弧法计算正常运行、洪水运行和特殊运行工况条件下的坝体安全系数均大于规范值,表明五道沟尾矿库在经历高速率筑坝且渗流场达到稳定状态后,在正常运行、洪水运行和特殊运行工况下整体处于稳定状态。     

Current situation and future trend of China rare earth luminescent material industry

<正>Rare earth luminescent material is one of the most important application sectors of rare earths.China enjoys the exceptional advantage to develop rare earth luminescent material for its abundant rare earth resources.After several decades'endeavor,China's rare earth luminescent material industry,headed by rare earth phosphor for lamp and LED and high efficient rare earth energy-saving light source,has been gradually developed into a scale industry.China has become a major production base of rare earth phosphor for lamps and rare earth     

China rare earth market review

正June 1~10,2014Rare earth market remained weak.Quoted price of rare earth products was similar to that in May.There was no sign of recovery in downstream market.The market of NdFeB magnetic materials and phosphor was depressed.Catalyst,polishing powder and ceramic industries remained inactive.Demand from downstream industry was soft.Consumers purchased on their needs.Suppliers had strong intention to sell.Prices of rare earth products     

Annual Report analysis of Chinese rare earth-related listed companies in 2013

<正>Chinese rare earth-related listed companies have published their 2013 annual reports.It can be understood from their reports that production and operation activities of Chinese rare earth-related companies were still heavily affected by macro economy and industrial policies.They basically followed the steps of national economy.In 2013,world economy recovered slowly but the economy     

Market opportunities and challenges for rare earth polishing powder

正1.Status of rare earth polishing powder Rare earth polishing powder with high content of cerium oxide began to replace iron oxide for glass polishing and became one of the key materials in glass polishing process since 1940.Compared with traditional iron oxide,rare earth polishing powder has many advantages,such as fast polishing rate,high polishing quality and long service life.It can achieve good surface quality and improve operation conditions.For example,in lens polishing,the polishing work that cerium     

Baotou Research Institute of Rare Earths developed a new RE alloy preparation technology

正Pyrometallurgy Laboratory of Baotou Research Institute of Rare Earths had independently developed a new preparation technology of rare earth alloy for NdFeB.The alloy can remarkably enhance the coercivity of NdFeB magnet but also evidently reduce the production cost of the magnet.The new master alloy was prepared in the kA pilot-scale electrolytic cell by the independent technology.The rare earth master alloy can be used as the raw material for NdFeB.Compared     

矿用防爆轴流对旋主要通风机叶片ANSYS模态分析及应用

高效节能矿用防爆对旋主要通风机的叶片是主要通风机运行的关键部件,叶片在运行时不断受到气流的作用力,从而使叶片产生振动,当叶片振动的频率与叶片的固有频率接近时,容易产生共振从而导致叶片的断裂。一旦叶片断裂时,对主要通风机的安全运行产生致命的影响,从而导致矿山、化工等企业发生重大事故,将会产生不可估量的损失。基于有限元分析软件ANSYS,对高效节能矿用防爆轴流对旋主要通风机叶片进行模态分析及产生对应的六阶模态频率,对主要通风机叶片的运行频率、固有频率及产生的共振问题进行了原理分析,并且解决了叶片频率共振的问题,从而为主要通风机叶片结构设计提供理论依据,并对主要通风机叶片的安全运行提供保障。     

2013 NdFeB export analysis

<正>China totally exported nearly 24,000 tonsof NdFeB products during 201 3,including 18,825 tons of permanent magnet,valued USD 1.34 billion at an average price of 71.4 USD/kg;3,277 tons of NdFeB magnetic powder,valued USD 1 01 million at an average price of 30.9 USD/kg;1,334 tons of strip casting ribbon,with total export value of USD 74million at an average price of 55.3 USD/kg;and 586     

Market and recycling of NiMH battery

<正>Market status and future trend of NiMH battery1.Global market of small NiMH battery Global market size of small NiMH batteries declined year on year since 2011.The trend will continue to 2018,at the rate of 5%to 10%annually.Demand for small NiMH batteries will be stable gradually.Many electrical apparatuses are powered by the built-in lithium battery today,which is the main reason for the shrunk market of small NiMH batteries.But,for some products,small NiMH     

China rare earth market review

正September 1-10,2014 Affected by the National Day holiday,rare earth transaction was stagnant and the market showed a weak steady state.As there was no good news for downstream market,some products with flat demand would likely rally slightly for some time to     

唐口煤矿深部复杂开采工作面瓦斯分源涌出规律研究

研究工作面瓦斯涌出规律对工作面瓦斯治理有重要意义。为了得到唐口煤矿深部3号煤层复杂开采条件下工作面回采时期瓦斯涌出时空演化规律,选取6304工作面作为对象,采用实测方法研究6304工作面瓦斯涌出规律。结果表明:6304工作面瓦斯涌出量为6.534 m³/min,其中煤壁占34.27%,落煤占29.62%,采空区占36.11%;沿工作面倾向由低到高,瓦斯浓度整体为上升趋势,其中1—76号架工作面瓦斯浓度小于0.20%,76—102号架瓦斯浓度上升明显,最大为0.387%;上隅角的后部采空区是工作面的瓦斯主要涌出源,上隅角1号测点瓦斯浓度0.78%,上隅角周边3号、5号、7号、8号、9号测点瓦斯浓度平均为0.643%;周期来压时,上隅角瓦斯相对平时较高。研究为针对性的瓦斯分源监控与灾害防治提供基础。