钢管混凝土支架在深井巷道中的支护实验研究

为解决华丰煤矿-1100m水平风井联络巷变形持续时间长、变形量大、难支护的问题,结合巷道围岩地质条件和巷道变形破坏特征,设计了以钢管混凝土支架为主的复合支护方案:支架断面为圆形,支架主体钢管采用219mm×8mm无缝钢管,充填C40混凝土,辅助锚网喷和围岩注浆加固。而后,利用FLAC3D对支护效果进行模拟分析,结果表明:巷道支护稳定后顶底板最大移近量为90mm,两帮移近量为80mm,围岩变形得到有效控制。最后,将复合支护技术成功应用于工程现场,充分证明基于钢管混凝土支架的复合支护能够有效控制巷道围岩变形,保证巷道的长期稳定。     

钢管混凝土支架在千米深井中央泵房中的应用

为解决华丰矿-1 100 m水平中央泵房巷道变形量大、变形持续时间长的支护难题,通过现场考察对巷道变形破坏原因进行深入分析,设计了高强度钢管混凝土支架复合支护方案:支架断面采用斜墙半圆拱形,支架主体钢管选用219 mm×8 mm无缝钢管,充填C40钢纤维混凝土,辅助锚网喷支护和围岩加固注浆。现场应用表明:基于钢管混凝土支架的复合支护技术,能够有效抑制围岩向巷道空间内移动,维护巷道的长期稳定和支护结构的安全可靠。     

冀家垴风井车场巷道变形破坏分析及支护对策

为解决新元矿冀家垴风井车场巷道的大变形问题,研究了风井车场巷道围岩的性质,系统分析了风井车场巷道的变形破坏模式,提出了优化巷道断面结合钢管混凝土支架+锚杆的复合支护方案,运用FLAC3D对比分析了2种支护方案下的巷道变形破坏特征,并将钢管混凝土支架复合支护方案进行了现场应用。研究结果表明:在原支护方案下顶板下沉量达1 100 mm,两帮收敛量达700 mm,断面收缩率为25%～29%;巷道围岩岩性差、频繁的动力扰动、支护强度低导致了风井车场巷道的大变形;采用钢管混凝土支架复合支护方案后,风井车场巷道围岩控制较好,顶板下沉量为45～55 mm,两帮变形量为25～35 mm,保证了风井车场巷道的正常使用。     

井下灌注式钢管混凝土支架支护技术

介绍了井下灌注式钢管混凝土支架的结构及性能,随后针对深井软岩巷道变形难以控制的问题,以鹤壁三矿三水平变电所为工程背景,结合现场考察、理论计算和现场监测等方法,提出了"锚网喷+封闭式钢管混凝土支架"的复合支护方案。结果表明:钢管混凝土支架可提供1.29MPa的支护反力,该复合支护有效地控制了软弱围岩的收敛变形,巷道支护稳定后围岩最终变形量小于80 mm,工程应用效果良好。     

基于钢管混凝土支架的复合支护技术在断层破碎带巷道中的应用研究

以阳城煤矿-650 m南翼轨道大巷为研究对象,深入分析了断层破碎带巷道地质参数,揭示了原有支护条件下巷道的变形破坏机理,基于承压环强化支护理论提出基于钢管混凝土支架的复合支护设计方案,在巷道内形成硬壳支护层。以有限元软件FLAC3D分析复合支护体受力性能,浅底拱圆形钢管混凝土支架最大轴力1914 kN,最大弯矩73.64 kN·m,出现在顶弧段左肩,支架极限受力在允许范围以内,满足支护稳定要求。-650 m南翼轨道大巷采用复合支护设计后支护结构稳定,巷道变形量小,表明基于钢管混凝土支架的复合支护设计适合断层破碎带巷道支护。     

特厚富水软岩巷道钢管混凝土支架支护技术研究

为解决查干淖尔一号井井底车场极软岩巷道支护问题,结合井底车场巷道围岩物理力学性质和原有支护条件下巷道破坏情况,运用修正的芬纳公式估算出围岩压力为0.9 MPa,计算理想状态下原有支护体可提供的支护反力为0.718 MPa,以支护体可提供的支护反力大于巷道稳定所需支护反力作为巷道稳定的必要条件,认为原有巷道发生变形破坏的主要原因是支护体支护反力不足,提出了钢管混凝土支架+厚混凝土喷层复合支护方案进行巷道返修,该方案理论上可提供1.48 MPa支护反力。结果表明:巷道返修完成2年后,两帮最大移近量为89 mm,顶底板最大移近量为142 mm。混凝土喷层没有开裂现象,巷道未发生明显变形,基于钢管混凝土支架支护技术的复合支护能有效控制巷道围岩变形。     

极软岩巷道交岔点钢管混凝土支架结构设计与应用

为解决极软岩巷道交岔点支护问题,结合钢管混凝土支架和极软岩巷道围岩的力学特性,分析了钢管混凝土支架控制极软岩巷道变形的机理。对查干淖尔一号井井底车场中3个极软岩巷道交岔点支护问题采用了工程类比法进行分析,结果认为:若能充分发挥钢管混凝土的结构优势,采用"194 mm×10 mm钢管混凝土支架+钢筋网+400 mm厚混凝土喷层"的支护方案可有效控制3个极软岩巷道交岔点的围岩变形。因此,设计了适用于极软岩巷道交岔点的钢管混凝土支架结构形式:极软岩巷道交叉点钢管混凝土支架,采用由支撑架和"C"形异形支架组成的组合结构。提出了查干淖尔煤矿井底车场3个交岔点的支护方案,并进行现场支护试验。现场支护试验证明:巷道交岔点支护2 a后,收敛量小于100 mm,巷道稳定性良好。     

大断面极软岩巷道钢管混凝土支架复合支护技术

为解决清水营矿+786 m水平临时水仓大断面软岩巷道变形严重难以控制的支护难题,现场考察了巷道变形破坏形态,取样测试了巷道围岩物理力学参数,分析了巷道变形破坏原因。研究得出:临时水仓巷道围岩属于典型的强膨胀型极软弱岩层,其变形主要由黏土矿物的滑移与吸水膨胀引起。基于上述研究,提出了"锚网喷+立椭圆形钢管混凝土支架+钢纤维混凝土碹体+加固锚索"的封闭式复合支护方案,建立了基于钢管混凝土支架的软岩巷道承压环强化支护力学模型,计算得出承压环的极限支护阻力可达1.99 MPa。随后运用FLAC~(3D)软件对不同断面形状的复合支护效果进行了对比分析,验证了设计方案的合理性。最后,该复合支护技术在井下获得了成功应用,工程应用表明:巷道支护3年多来,围岩最终变形量小于100 mm,并且支护体力学性能良好,有效地控制了大断面软岩巷道的收敛变形。     

杨庄矿软岩巷道锚杆与钢管混凝土支架联合支护技术研究

杨庄矿Ⅲ水平南大巷软岩巷道围岩强度低,黏土矿物含量高,吸水泥化现象严重,巷道围岩变形量大,锚杆失效较为普遍。结合南大巷软岩巷道围岩变形特点,设计了锚杆与钢管混凝土支架联合支护方案。巷道断面采用马蹄形,锚杆为Φ20 mm×L1800 mm的左旋螺纹钢锚杆,钢管混凝土支架主体钢管选用Φ194 mm×L8 mm无缝钢管,灌注C40核心混凝土。结合理论计算可知,设计支护方案的极限承载能力大于南大巷围岩荷载,能够维持巷道围岩的稳定。通过数值分析和现场监测分析可知,巷道围岩变形较小,锚杆和钢管混凝土支架支护作用力均小于其极限荷载,支护结构稳定,所以锚杆与钢管混凝土支架联合支护方案满足了Ⅲ水平南大巷软岩巷道支护的要求。     

新安煤矿深井软岩硐室钢管混凝土支架支护设计与应用

新安矿变电所巷道埋深约750m,属于极软岩难支护巷道。文章结合工程地质条件,采用钢管混凝土支架的复合支护技术解决变电所软岩巷道难支护问题,通过3个月的支架荷载监测和巷道变形测量表明,"Φ194mm×10mm的钢管混凝土支架+支架壁后250mm厚矸石袋"的复合支护稳定可靠,支架结构提供的支护反力大于围岩荷载,可满足巷道围岩稳定要求。     

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     

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