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《建井技术》2018,(6)
基于岩石低温损伤问题,为进一步研究砂岩低温下物理力学性质变化,对高家堡煤矿525,657和782 m深度层位砂岩,进行了不同低温(-15~-5℃)下的单轴压缩试验,观察3个深度层位砂岩在不同低温下的单轴压缩后的破坏模式,并分析应力、应变变化规律以及单轴抗压强度、弹性模量和泊松比随温度的变化规律。试验结果表明,在试验温度范围内,砂岩单轴抗压强度、弹性模量和泊松比均受温度影响较大,单轴抗压强度和弹性模量随温度的降低而增加,泊松比随温度的降低而减小。拟合出砂岩单轴抗压强度、弹性模量和泊松比随温度的变化曲线,得出结论:砂岩单轴抗压强度和弹性模量在-15~-10℃温度范围内的变化率,比在-10~-5℃温度范围内更大;而其泊松比变化率受温度影响不大。 相似文献
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常俊松 《有色金属(矿山部分)》2022,74(5):122-128
为研究深部花岗岩物理力学参数随赋存深度变化的变异性,通过对某金矿19~1 320 m深度水平的花岗岩岩样的岩石参数(单轴抗压强度、弹性模量、泊松比、黏聚力、内摩擦角、天然重度等)统计分析,结果发现,岩石参数变异系数大小顺序为:弹性模量>单轴抗压强度>黏聚力>泊松比>内摩擦角>天然重度;单轴抗压强度、弹性模量、黏聚力、内摩擦角、天然重度随着深度增加有线性增大趋势,而泊松比随深度增加有线性减小趋势;根据地质统计学的变异函数,拟合出岩石参数最优模型,分析了岩石参数在空间变异的性质,天然重度在赋存深度尺度内变异性小,而弹性模量和单轴抗压强度变异性较大。许多学者对土的参数变异性研究相对较多,而对岩石参数的变异性研究相对较少,以岩石试验为基础对岩石参数进行分析,揭示了岩石参数随赋存深度变化的规律及变异性,对深部开采有一定参考意义。 相似文献
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构建不同结构特征的离散裂隙网络,然后建立相应的等效岩体模型,通过单轴压缩数值试验得到等效岩体模型的力学参数,分析离散裂隙网络的几何参数对裂隙岩体力学参数的影响。结果表明:随着裂隙密度P32的增加,单轴抗压强度、弹性模量及峰值应变近似线性递减,泊松比近似线性递增;随着裂隙倾角均值的增加,单轴抗压强度、弹性模量及峰值应变先减小后增大,泊松比先增大后减小,在60°时达到极值;对于裂隙倾角的分布特征,当裂隙倾角均值为60°时,单轴抗压强度、弹性模量及峰值应变随Fisher分布常数的增加而减小,泊松比随Fisher分布常数的增加而增加,而对于其它裂隙倾角均值的情况,Fisher分布常数对裂隙岩体力学参数的影响较小;对于裂隙直径的分布特征,幂律分布指数对裂隙岩体力学参数的影响较小;敏感性分析结果表明,单轴抗压强度对于离散裂隙网络几何参数的敏感性最大,弹性模量的敏感性最小。 相似文献
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为解决复采过程中不同尺寸遗留煤柱失稳致灾难以判定的问题,对不同高径比煤岩试件进行单轴加载实验,研究不同高径比对煤岩试件破坏形式、应力应变曲线形式、峰值强度、峰值应力、弹性模量的影响规律。结果表明:随着高径比的减小,试件的破坏形式由剪切破坏为主过渡为复杂破坏形式;峰值应力σmax和峰值应变εP随高径比的减小呈幂函数增大,两者间随高径比增加呈一次函数关系:εP=0.218σmax-2.465;弹性模量及割线模量随着高径比的减小而减小,其变化趋势服从二次函数; 0.8和1.5是引起煤岩试件力学参数变化速率改变的关键高径比,高径比小于0.8时,力学参数变化明显,而大于1.5后变化趋缓。上述结果可应用于不同宽高比煤柱稳定性的判定,提高了复采安全。 相似文献
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《现代矿业》2017,(6)
为确定物理模拟试验相似材料的配比,以砂子、水泥和石膏为相似材料,通过正交表L9(34)分别对模拟矿石、模拟围岩进行正交配比试验,并由多元线性回归分析得出相似材料配比与物理力学指标的回归方程。结果表明:(1)砂胶比、水石比、水料比3个因素中,砂胶比对模拟材料的影响程度最大,水石比次之,水料比最弱;(2)3个因素对密度均有一定影响但不明显,单轴抗压强度随砂胶比的增大而显著减小,随水石比和水料比的增大而缓慢增大;弹性模量随砂胶比的增大而显著减小,随水石比的增大而增大;(3)回归方程能较好地适用于用砂子、水泥、石膏制备的模拟材料的单轴抗压强度和弹性模量的计算。试验结果可为确定其他模拟矿体、围岩等相似材料的配比提供参考。 相似文献
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《煤炭科学技术》2021,49(7)
针对裂隙分布对岩柱或煤柱强度和稳定性影响问题,采用合成岩体模型技术(SRM)重构岩柱模型,研究裂隙密度和裂隙倾角对岩柱稳定性影响。合成岩体模型中分别采用平直节理黏结模型(FJBM)、光滑节理模型(SJM)和裂隙网络模型(DFN)模拟岩块、裂隙和裂隙网络。通过单轴抗压试验和单轴抗拉试验标定岩块宏观力学参数(单轴抗压强度、抗拉强度、杨氏模量和泊松比),数值模拟标定结果与试验结果对比表明数值模拟模型细观力学参数能够很好地匹配实验室岩样宏观力学参数。研究结果表明:岩体内裂隙将显著降低岩体抗压强度,岩柱强度随裂隙密度P21增加而降低;裂隙密度P21由1 m/m2增加至5 m/m2,岩柱平均强度由103.5 MPa降低至69.5 MPa,岩体抗压强度与裂隙密度负相关;裂隙倾角由0°增加至90°,岩柱抗压强度呈"U"形变化;裂隙密度较小时,岩柱易形成"X"形压剪破坏,裂隙密度较大时,岩柱"X"形压剪破坏逐渐消失;岩柱产生的微裂隙与岩体裂隙密度负相关;裂隙倾角小于临界角φ或大于45°+φ/2时,岩柱易形成"X"形压剪破坏,而当裂隙倾角介于φ与45°+φ/2时,岩柱易形成剪切滑移破坏。岩体合成技术可为确定岩柱强度确定提供一种思路。 相似文献
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《中国稀土信息(英文版)》2014,(10)
<正>Developing ecological lighting source The world is facing the big problem of energy shortage today and the contradiction between economy development and environmental protection is worsened.Therefore,people are more likely to choose an ecological light source that is more energy efficient and environmental friendly.The choice provides great opportunity for the development of rare earth optical material industry in China.The concept of green lighting positions rare earth luminescent material as a leading player in illumination market.The light source of both rare earth luminescent lamp and LED lamp is ecological and energy saving.This is why 相似文献
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《中国稀土信息(英文版)》2014,(8)
正Galaxy Magnet announced its financial results for the first half of 2014 on August 14.For the first six months ended on 30 June 2014,Galaxy Magnet achieved operation income of RMB 182.3 million,up8.40% over the same period of 2013,and the net profit attributable to the shareholders of the listed company of 34.02 million yuan,increasing 35.49% over the same period of last year.Stable performance increase was led by development of new customers and application market of magnets. 相似文献
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<正>China has rich rare earth resources.Output of rare earth and steel in China ranks the top first in the world.However,there is still certain distance between the steel produced in China and developed countries from the point of varieties and quality.China still has to import some types of steel.Improving the quality should be emphasiZed in future development of steel industry in China.Rare earth can be used to upgrade traditional steel 相似文献
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《中国稀土信息(英文版)》2014,(12)
正November 21~30,2014Due to weak demand from downstream industries,transactions of rare earth in Chinese domestic market were inactive.It was difficult to sell any rare earth products except for dysprosium oxide and terbium oxide.Suppliers lost confidence in recent market.Demand for rare earth products was soft.Consumers continued to take a wait-and-see attitude.Rare earth export market remained slow. 相似文献
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分析了近年来国内外稀散金属产业的生产、应用、资源与市场状况.铟锡氧化物靶材、砷化镓晶片、锗红外材料、铼高温合金和硒在电解锰及玻璃的应用等已成为稀散金属的主要应用领域.稀散金属的产量快速增长达到历史高位而导致了市场的失衡.以GaInP_2/GaAs/Ge,CIGS和CdTe为代表的非硅系太阳能电池是稀散金属的新兴应用领域,将给稀散金属带来日益增长的需求. 相似文献
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<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 相似文献
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《中国稀土信息(英文版)》2014,(6)
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 相似文献
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YANG Li 《中国稀土信息(英文版)》2014,(6)
<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 相似文献
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Gao Wei 《中国稀土信息(英文版)》2014,(11)
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 相似文献
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《中国稀土信息(英文版)》2014,(8)
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 相似文献