动压沿空掘巷支护技术研究及应用

为解决泄水巷支护的问题,提出采用预应力耦合让压支护体系的方案。通过锚杆让压性能试验、锚杆拉拔现场试验,确定本方案有效控制大采深动压巷道变形量;通过观测分析,证明该支护体系能够有效控制动压巷道变形。     

动压巷道离层变形特征及支护技术研究

为了对比分析不同支护方式下围岩离层变形过程的差异,以铜川矿区复合顶板动压巷道为例,在同一回采巷道内分别设置工字钢棚试验段和锚杆支护试验段,采用巷道矿压在线监测系统实测两种支护方式下围岩离层变形的动态过程,探究不同支护方式下的围岩变形机理,为确定合理的巷道支护方式提供依据。实测结果表明:主动支护和被动支护时动压巷道离层变形过程有本质区别,在锚杆支护地段深部与浅部围岩以同步变形为主;而在工字钢架棚支护段,深部与浅部围岩的位移量差别较大,出现了较大的离层空间,棚式支护不能满足围岩变形要求。根据试验巷道围岩支护体的信息反馈结果,动压巷道应该采用主动支护方式,据此采用高预应力强力一次支护理论进行了动压巷道支护方案优化设计,改进后的支护方案能够满足动压巷道的支护要求。     

深部动压巷道高阻让压支护技术研究

为解决深部动压巷道支护的技术难题,针对曹村煤矿十采区下部人车下山巷的具体工程地质条件与生产技术条件,在现场地应力实测的基础上,采用巷道支护专家系统软件对动压巷道支护形式与参数进行优化设计,确立了以高强让压锚杆与带肋锚索为核心的新型“高阻一让压”支护体系,并进行了井下工业性试验和矿压监测.研究结果表明:基于地应力实测的高强让压锚杆和带肋锚索联合支护提高了支护结构的整体承载力,有效控制了围岩的变形,达到了支护设计的预期效果,保证了动压巷道的稳定和正常使用.     

高强预应力让压锚杆在深厚煤层采动区支护实践

张双楼矿9420溜子道在深部厚煤层采动影响区的地质条件下掘进,在巷道帮部采用高强预应力让压锚杆进行支护实践.通过巷道变形观测以及与帮锚索、锚网梁+套棚支护方式巷道比较、分析,表明高强预应力让压锚杆在深部厚煤层采动影响区巷道支护是匹配的,实现了安全、经济、快速掘进的目的,为同类型复杂条件下的巷道掘进提供了借鉴经验.     

动压软岩巷道用让压锚杆的设计与性能分析

针对巷道支护技术的现状,研究了在动压软岩巷道中使用锚杆支护技术的特点以及存在的问题,提出了一种新型的适用于动压软岩巷道中的让压锚杆,介绍了该新型锚杆的设计原理及总体结构,然后对锚固头的受力特点进行了研究和分析,通过理论推导和仿真求解得到其性能曲线。分析表明该新型让压锚杆可以有效提高动压软岩巷道的支护效果。     

郭屯煤矿动压沿空巷道破坏机理及支护控制

针对郭屯煤矿1103运输巷受采动影响围岩应力分布和巷道变形不均的问题,提出了预应力让压非对称支护方案。通过理论分析、数值模拟和工程观测,分析了动压巷道围岩破坏机理,并对锚网支护参数进行了研究,得出最佳支护方案,并应用于工程实践。结果表明:预应力让压锚杆在接近锚杆屈服极限前,能够迅速承受载荷,保证锚杆系统不发生塑性破坏;设计高强预应力锚杆的预应力为60 k N;顶板锚杆布置5根,帮部锚杆布置4根;锚索位置偏向于沿空侧。设计支护方案极大地改善了原有支护状态,控制了巷道围岩稳定,使应力分布非对称的巷道围岩控制在变形基本对称的范围内。     

深部大变形巷道锚杆支护理论与技术研究进展

深部大变形巷道的锚杆支护问题是目前煤炭开采领域科学研究的热点之一.简要总结了传统的锚杆支护理论和近年来国内外学者专家提出的深部巷道支护新理论和新技术,介绍了本团队在深部巷道锚杆支护研究方面取得的阶段性成果.认为深部巷道围岩存在不可控的"给定变形";锚杆预应力及支护阻力无法控制深部巷道塑性区的发展,预应力对抑制破碎区围岩的离层、剪胀等非连续变形作用较大;锚杆施加高预应力可在围岩中产生较大压应力带,充分发挥锚杆主动支护作用与群锚功能,可有效降低塑性区向深处扩展速率;锚杆从支护到失效,其锚固力随围岩变形一般要经历稳定、减小、残余锚固力3个阶段;深部大变形巷道锚杆支护应满足2个条件,所受载荷不超过极限强度、锚固基础不受塑性区影响;采用基于高阻让压设计理念的可接长锚杆能较好的适应深部巷道锚杆支护要求.     

动压巷道锚杆条带碹支护技术研究与应用

针对强烈动压造成巷道大变形、强破坏的技术难题,以阳煤新元煤矿9号煤辅运大巷为工程实例,从工程布局上分析巷道矿压显现特征,为缓解原支护中存在的技术缺陷,提出锚杆条带碹支护的巷道支护理念,运用先柔后刚、刚柔并举、抗让结合的原则,巷道初期支护采用"锚网喷"联合支护,后期支护采用柔模混凝土碹体支护。工程实践表明:采用锚杆条带碹支护,有利于锚索预应力的扩散,围岩的整体承载能力得到极大增强,巷道围岩变形量明显减小,表明锚杆条带碹支护方案对动压影响下巷道围岩控制有较好的效果。     

新型让压锚杆在大埋深沿空掘巷中的技术应用分析

随着矿井开采深度的不断增加,矿山压力越来越明显,巷道支护问题越来越突出,特别是在深部沿空掘巷施工的煤巷,已成为煤矿巷道支护面临的突出难题。天安十矿针对此类巷道应用高强预应力让压锚杆、锚索联合支护,较好地解决了巷道支护难的问题,结合现场应用,文章详细介绍了让压锚杆的支护原理、支护参数选择、施工工艺及技术要求。     

深部煤矿巷道预应力锚杆支护的研究和应用

随着煤矿开采深度的逐年增加,深部开采已成为必然趋势.作为深部煤层巷道的支护方式之一,预应力锚杆支护已渐成为主要的支护方式.在此背景下,通过搜集国内外相关资料,总结了现有的预应力锚杆支护研究方法;在对预应力锚杆受力和锚固机理的研究成果分析基础上,阐述了预应力锚杆支护技术目前在深部煤矿巷道中的应用现状, 深入探讨了预应力锚杆支护技术的研究目前存在的不足及现场应用的局限性,并指出了进一步研究的方向.     

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。