某矿区帷幕注浆工程施工隐患分析及加密孔的布置

帷幕注浆工程查漏补缺阶段是帷幕能否实现最终堵水目标的最后一道防线,对帷幕堵水效果具有决定性意义。通过矿区构造分析可能存在的导水位置,帷幕内外观测孔水位变化确定平面上的通道范围,单位注浆量垂向权重分析、单位注浆量变化曲线分析和注浆施工异常情况分析具体确定帷幕隐患位置,可较为准确地布置加密孔的位置。以上由面到点的分析判断帷幕施工隐患的方式,为加密孔的布置提供了充分的依据,在矿山帷幕注浆施工过程中具有较好的推广意义,同时也为国内类似条件矿山帷幕注浆工程提供了借鉴。     

矿山帷幕注浆方案研究及堵水效果综合分析

在分析中关铁矿水文地质条件的基础上,确定了该矿山治水采用全封闭帷幕注浆的堵水方案。在施工过程中,对西线帷幕注浆工程采用叠加效应分析、离散性分析、高密度物探测试及检查孔检验等手段进行注浆幕体施工质量及防渗效果检查和评价,结果表明,帷幕注浆参数设计合理,帷幕体具有较好的抗渗性能,可满足矿山治水和安全开采的要求。     

注浆孔布置方式对工作面超前预注浆效果的影响

为了分析不同注浆孔布置方式对工作面超前预注浆效果的影响,建立数值模型对工作面和回采巷道的应力和位移进行研究。研究结果表明:单排孔、三花孔分别更适合控制工作面煤壁上部、煤壁下部的片帮,注浆孔布置方式对工作面煤壁中部片帮的影响很小。随着注浆孔长度的不断增加,巷道注浆侧围岩的承载能力逐渐增强。三花孔比单排孔能更好的减小巷道顶板沉降。无论单排孔还是三花孔,巷道煤壁的水平位移主要取决于上排孔的位置。     

组合钻孔在帷幕注浆中的应用

深埋矿体和复杂地质条件给钻探施工带来了极大的困难,是帷幕注浆面临的重大难题之一。依托于某矿北部帷幕注浆试验工程,成功将直孔+S型分支孔+“鱼刺”型分支孔相结合的组合钻孔应用到帷幕注浆中,有效地提高了钻孔对高角度裂隙的切割概率,保障了幕体的防渗性能,增加了帷幕注浆浆液扩散范围,提高了矿山帷幕注浆工程施工的安全度。同时,根据实际钻探施工情况,及时进行信息化施工调整,对钻孔组合布置、设计参数及施工工艺进行优化改进,保证工程质量的前提下,降低了施工难度,减少了钻窝的施工数量,有效降低了矿山投资。研究成果不仅为整个帷幕工程提供了技术支撑,还为国内类似条件矿山帷幕注浆工程提供了借鉴。     

数值模拟技术在动态控制帷幕注浆中的应用

在新桥矿业公司的治水工程中,利用数值模拟技术优化注浆帷幕线位置、帷幕参数、注浆孔布置,动态指导施工,达到了减少注浆钻孔量和工程投资,提高帷幕堵水效果,最大限度的控制矿山水害的目的。     

中关铁矿注浆帷幕检查孔设计施工与优化

帷幕注浆是新兴的矿山治水常用的重要手段,帷幕体抗渗效果的检查通常采用施工检查孔的方式。对中关铁矿帷幕注浆工程已完工区段施工质量进行分析与研究,最终确定了检查孔布置原则,根据此原则对相应区段布置了一定数量的检查孔,通过大量资料的分析,认为钻孔透水率与单位注灰量不存在对应的线性关系,因此,检查孔按注浆孔进行注浆施工是非常必要,按上述研究成果进行了检查孔的设计与施工,检查结果表明,幕体具有较好的搭接效果,帷幕体防渗性能满足q≤2 Lu的设计指标。     

中关铁矿帷幕注浆工程施工耗时分析

在帷幕注浆工程中,施工耗时的主要环节是成孔耗时和注浆耗时。在成孔过程中,由于复杂的地质条件、施工技术水平、施工经验和责任心,操作工艺以及采用的设备等因素的影响,大大增加了成孔的难度,成孔耗时增加;在注浆过程中由于受注浆工艺,注浆设备和注浆材料的影响,也增加了注浆耗时。通过对中关铁矿帷幕注浆施工中的成孔耗时、注浆耗时、纠斜耗时和待工耗时分析,提出了帷幕注浆施工耗时的防范措施。     

大红山矿帷幕注浆治水工程及其评价

大红山矿大理岩岩溶发育,由于突水造成井下大量涌水,同时引起地下水位急剧下降,引发了较大范围、较大规模的地面塌陷。通过幕址勘察、帷幕注浆设计及施工,并从钻孔单位注浆量分析、帷幕内外地下水位观测、坑道抽水试验、钻孔电磁波透视和钻检查孔等多个方面,对帷幕注浆治水效果进行评价,确认注浆帷幕堵水效果明显,帷幕注浆质量较好,可发挥显著的截流作用。     

白垩系红层底砾岩帷幕注浆施工技术

在白山坪矿南翼白垩系红层底砾岩体中实施帷幕注浆,安全、优质、高效地完成注浆设计及施工任务,并取得了良好效果.对注浆技术、施工工艺、注浆参数的选取、经济效益等技术问题进行了分析探讨.     

地下含水层帷幕注浆单液水泥浆扩散规律研究

帷幕注浆逐渐成为矿井水害防治的主要技术手段之一,为解决帷幕工程中注浆孔间距的布设问题,通过室内试验得到帷幕注浆材料单液水泥浆的物理性能参数,采用COMSOL数值软件建立了地下含水层帷幕注浆单液水泥浆扩散数值模型,研究了地下含水层帷幕注浆工程中单液水泥浆的扩散机制。研究结果表明:单液水泥浆水灰比越大,浆液的凝结时间越长黏度越大,而结石率与抗压强度越小,根据所得浆液性能参数针对不同地层特征选取相应水灰比的浆液进行注浆;地下含水层帷幕注浆单液水泥浆的扩散形式以注浆孔为中心的圆形扩散,单液水泥浆的扩散半径随注浆时间的增加而增大,且扩散半径最终趋于稳定,稳定后的浆液扩散半径平均值为10.22 m,浆液扩散的范围可达到20.44 m;单液水泥浆扩散半径的理论计算与数值计算结果较为一致,理论解与数值解之间的误差小于5%,证明作者建立的数值模型用于研究帷幕注浆浆液扩散范围具有一定的可靠性。基于研究结果,选取帷幕注浆孔距为20 m,2排交错布孔,建立有效宽度约为40 m的帷幕墙,以阻隔帷幕墙外侧含水层中地下水向井田内的补给。帷幕墙建造完成后,通过检查孔对受注地层进行取心,得到含有浆液结石体的岩心,实验室...     

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     

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     

2014 second batch of rare earth quota released

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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