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岩体力学参数一直是困扰岩石力学和数值计算深入研究的难题,它在很大程度上决定了数值计算结果的准确性、客观性和实用性.本文在岩体损伤力学描述的基础上,提出了弹性波波速、损伤力学和反分析相结合的优化方法. 相似文献
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构造预测是当前煤矿生产中急需解决的一项重要课题,特别是随着采掘机械化程度的不断提高、液压支架联合机组使用以后,更需要在未采掘之前就能预见到采区、采面内将要出现的各种构造形迹。过去有些矿井只是孤立地从形态方面研究构造,因而很难做到、或者做好预测工作。而运用地质力学的观点和方法,就能使预测工作建立在更有科学根据的基础上。构造体系是地质力学的核心,本文将主要介绍应用构造体系或构造型式的展布特点来进行的构造预测工作。而研究岩石的力学性质和应力状态,能够对不同煤层、不同地段的构造做出更为合理的推断;应用数理统计的方法则可帮助我们由定性预测向定量预测发展。文中也对这两方面的内容做些说明。 相似文献
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In the process of combustion of coal organic and inorganic materials in it will undergo a complex variation.Part of thew will become volatiles and,together with coal smoke,enter into atmosphere,some will remain in micro-particulates such as ash and dust and find their way into atmosphere in the form of solid particles,and the rest will be retained in ash and slag.Coal ashes are the residues of organic and inorganic substances in coal left after coal combustion and the compostition of coal ashes in dependent on that of minerals and organic matter in coal.This paper deals with the chemical composition of coal ashes,the distribution of trace elements in them and their petrological characteristics,and also studies the relationship between the yield of coal ashes and the distribution of trace elements.In addition,a preliminary study in also undertaken on the factors that affect the chemical composition of coal ashes.As viewed from the analyses of coal ash samples collected from the Yanzhou mining district,it can be seen clearly that coal ashes from the region studied are composed chiefly of crystalline materials,glassy materials and uncombusted organic matter and the major chemical compositions are SiO2,Al2O3,Fe2O3,and CaO,as well as minor amounts of SO3,PWO5,Na2O,K2O and TiO2.During the combustion of coal,its trace elements will be redistributed and most of them are enriched in coal ashes.At the same time,the concentrations of the trace elements in flying ash are much higher than those of bottom ash,i.e.,with decreasing particle-size of coal ashes their concentrations will become higher and higher.So the contents of trace elements are negatively proportional to the particle-size of coal ashes.There has been found a positive correlation between the trace elements Th.V.Zn,Cu and Pb and the yield of coal ashes while a negative correlation between Cl and the yield of coal ashes. 相似文献
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三种Rmaxo分别为0.67%,3.41%和4.90%的煤样,在t=350-700℃、Pc=400-600MPa、ε=10%-30%、ε=3.63×10-4-2.59×10-5s-1条件下的变形实验表明:(1)煤光性组构的成因是芳环层片在构造应力作用下重新定向所致,重新定向的主要机制是煤化过程中芳环层片的择优成核生长,同时存在物理转动定向机制的作用;(2)芳环层片的重新定向主要发生在煤级相对较低阶段,VRI的Z轴主要反映这一阶段的构造应力方向;(3)YRI的形态特征并非仅与有限应变有关,它不能直接作为有限应变分析的标志。 相似文献
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阜新盆地反转构造的特征 总被引:1,自引:0,他引:1
阜新盆地在阜新期开始反转,主要反转作用发生于阜新组沉积之后,在盆地反转过程中北东向-北北东向断层发生左旋走滑逆冲,东西向及北西西向断层发生右旋走滑逆冲,并形成一系列北东向反转褶皱。反转构造煤层埋藏变浅,有利于开采。 相似文献
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三种R_(o_1max)分别为0.67%,3.41%和4.90%的煤样,在T=350—700℃、P_c=400—600 MPa、ε=10—30%,(?)=3.63×10~(-6)—2.59×10~(-5)s~(-1)条件下的变形实验表明:(1)煤光性组构的成因是芳环层片的构造应力作用下重新定向所致,其主要机制是煤化过程中芳环层片的择优成核生长和物理转动定向,它主要发生在煤级相对较低阶段:(2)VRI 不能直接作为有限应变分析的标志,其Z 轴主要反映煤级相对较低阶段的构造应力方向;(3)气体的存在是引起煤层构造变形较为强裂的关键因素;(4)影响煤脆-韧性变形机制转换的主要因素是煤级条件,其韧性机制主要发生在煤级较低阶段,而在煤级较高阶段则以脆性机制为主. 相似文献
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古构造应力场对芙蓉矿区煤与瓦斯突出起主控作用。本文采用煤镜质体有限应变分析、Etchecopar电算、共轭剪节理解析以及有限元模拟等方法对其作了定量化研究。结果表明:矿区现存构造是在最大主压应力方向分别为194°∠23°和145°∠29°的两期应力场作用下产生的,对应构造差应力分别为21MPa和23MPa,使全区各级构造呈北东向和东西向为主的复合叠加规律。这些不同构造型式对矿区煤层气赋存及煤与瓦斯突出具有不同的控制方式。 相似文献