东乡铜矿-135m中段11线运输大巷道形变构造应力场分析

介绍东乡铜矿135m中段11线运输大巷道形变区的地质构造特征、主应力轴方位以及构造应力场分布规律，分析巷道形变与应力状态的关系。巷道施工破坏岩层中原始应力状态，而巷道形状、大小、方向以及支护型式是影响新应力状态的重要因素。平巷断面呈矩形、梯形、圆弧形时，围岩稳定性由差变好。圆弧形断面长轴方向抗压强度最大，马蹄拱型发碹垂向和侧向抗压强度最大，三心拱型发碹铅直方向抗压强度最大。拱顶剪切变形是δ1铅直方向分力和δ2铅直方向分力及中轴应力的“合力”作用所致。     

新型单向岩体应力,应变匹配系列传感器的研制

新型单向岩体应力、应变匹配系列传感器，是最新研制的应用于岩体及相似材料模型等压力、变形量测量的匹配型系列传感器，其弹性元件的弹性模量与被测岩体的弹性模量相等，是岩体应力、应变定量测量型传感器它可以同时测得岩体被测点的压力和变形量，其测量范围为硬岩、中硬岩体、软岩、具有一定弹性模量的相似材料和土壤等的应力、应变测量经过在井筒及其围岩和相似材料模型上的应用，其重复性、稳定性等技术指标满足了岩体和相似材料模型的测试     

矿用采动应力监测传感器的比较和应用

应力和应变测量已广泛应用于地应力测量中,其采动应力监测则是一种典型的相对地应力测量。重点分析了两种典型的采动应力监测仪器,即钻孔应力计和空心包体式钻孔三向应变计的技术特点,以及在采动应力监测中的优缺点。     

运输巷道底板的动力破坏

塔什塔戈尔矿床有构造地质应力场,其水平分力比垂直分力б_3(等于γH)大0.8～2倍。因此,最大压缩应力集中系数在巷道的顶板和底板。该系数大约是30б_3。这样高的应力与高模量的脆硬岩石相结合,引起巷道周边岩石,特别是垂直于最大水平构造地质应力布置的巷道周边岩石,产生动力破坏。     

利用弹性元件提高螺栓疲劳强度的分析计算

现有文献称“在螺母下面安装弹性元件，起到了柔性螺栓的效果”。笔者对这种螺栓联接进行了受力与变形分析，得到了弹性元件刚度对螺栓相对刚度系数影响的解析式。有力说明了利用弹性元件可以达到提高螺栓疲劳强度的目的。此外，通过实例对弹性元件进行了参数的优化设计计算     

煤矿井下空心包体应力解除法地应力测量层位选择方法

在分析煤矿井下围岩强度、结构面和岩层倾角对空心包体应力解除法地应力测量影响的基础上,提出在煤层顶板采用空心包体应力解除法进行地应力测量时,利用检测钻孔孔内围岩信息确定测量层位的方法。在测点附近首先施工检测钻孔,在孔内进行围岩结构观测和围岩强度测试,结合两方面测试结果设计测量钻孔参数;采用该方法能大幅度提高测试成功率及测试数据质量。通过井下实测,介绍该方法的应用过程和测试效果,并提出测量钻孔轴线与岩层层面夹角以30~60°为宜。     

深部煤体非线性蠕变本构模型及实验研究

深部煤体蠕变规律研究对控制巷道围岩变形,预防煤与瓦斯突出及改善瓦斯抽采效果具有重要意义。基于分数阶导数流变模型,推导出煤体三维应力条件下非线性蠕变本构方程。考虑深部煤体赋存的高应力环境及应力变化路径,进行了三向应力状态下轴压恒定、分级卸围压的煤体蠕变实验。实验结果表明:在三向高应力状态下,试件的轴向和环向应变表现为初始蠕变和稳态蠕变,最终出现加速蠕变阶段;在相同差应力条件下,煤体蠕变变形随围压增大而减小。利用煤体卸围压蠕变实验数据对文中蠕变本构方程的参数进行拟合,结果表明:该蠕变本构方程能很好地描述煤体蠕变三阶段,特别是加速阶段。在蠕变本构方程参数确定的前提下,分析了应力水平、分数阶导数阶数及黏性系数对煤体蠕变特性的影响规律。     

煤矿深部流变岩体中压力传感器的应力分布规律

流变应力恢复法是针对煤矿深部软岩而提出的一种地应力测量新方法,该方法基于煤矿深部软岩的强流变力学行为,采用在围岩钻孔中埋设压力传感器的方法来获取实测应力,进而根据压力传感器的实测应力来分析岩体的初始应力。为了解压力传感器在煤矿深部流变岩体中的测量特性,对流变岩体中埋设压力传感器并注浆回填的二维平面应变问题进行理论分析,推导岩体为黏弹性三参量固体模型和Burgers模型时压力传感器实测应力的解析解;通过参数分析,揭示浆液凝固时间、浆液力学性质及岩体黏弹性参数对压力传感器实测应力的影响规律。     

基于三铰斜拱的不同宽度区段煤柱下底板应力变化规律研究

为获取上保护层充分采动后,区段煤柱影响下的上覆岩层结构及底板应力传递规律,基于三铰斜拱理论推导了合理拱轴线方程;数值模拟了不同宽度区段煤柱的保护层底板应力分布规律;基于三铰斜拱和弹性力学理论2种方法得到了保护层底板应力分布的解析解,并通过现场实测验证。研究表明：三铰斜拱形态参数与留设煤柱宽度、煤层开采高度、采空区卸压宽度等动态相关;当煤柱宽度大于15 m时,采空区底板重新压实区将产生三铰斜拱结构引起的附加应力,并且应力极值点随煤柱宽度增加而向采空区中心移动。现场试验得出被保护层回采巷道应内错布置,合理错距为10～20 m。     

多向应力状态下测定岩石弹性参数的探讨

测定岩石的弹性参数,是作好技术先进,经济合理的地下工程设计的基础。地下工程中,岩石一般处于双向或三向应力状态,因此在多向应力状态下测定岩石弹性参数较为合理。以劈裂试验及三轴压缩试验方法的应力分析为基础,本文提出计算岩石弹性参数的新方法。文中利用九种不同岩石的劈裂试验结果,求出了弹性模量及泊桑比,并与单向压缩试验求得的参数作了对比,其结果证明所提出的方法可以满足实用要求。     

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。