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学力理论指导下的中学生阅读力评价初探
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作者 杨相士 《新课程(教研版)》 2013年第5期158-160,共3页
在学力理论指导下,对中学生阅读力的精确量化操作设想,对学生的基础阅读能力和基本阅读技能;阅读动力和阅读毅力;个性化阅读感悟和人格提升等方面有一个比较科学、规范、量化的考核标准。通过定性方法进行基础阅读力的判定,通过观察和... 在学力理论指导下,对中学生阅读力的精确量化操作设想,对学生的基础阅读能力和基本阅读技能;阅读动力和阅读毅力;个性化阅读感悟和人格提升等方面有一个比较科学、规范、量化的考核标准。通过定性方法进行基础阅读力的判定,通过观察和学生互评、学生自主考核等方法进行阅读动力与阅读毅力的判断与促进性考核,通过学生自我评判、自我感悟等方法促进学生在阅读过程中得到科学的指导和提升主动阅读欲望,从而在量化评价操作中提升学生阅读力。 展开更多
关键词 学力理论 中学生 阅读力 评价
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学力理论的历史发展 被引量:52
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作者 钟启泉 《全球教育展望》 CSSCI 北大核心 2001年第12期31-38,共8页
“学力”是运动的、发展的。各个时代与社会所要求的“学力”是受那个时代的社会理想和要求所制约的。然而 ,应当规定怎样的“学力” ,不应当仅仅取决于社会理想、社会要求之类的社会因素。作为个体或集体的学习者所具有的认知发展方向... “学力”是运动的、发展的。各个时代与社会所要求的“学力”是受那个时代的社会理想和要求所制约的。然而 ,应当规定怎样的“学力” ,不应当仅仅取决于社会理想、社会要求之类的社会因素。作为个体或集体的学习者所具有的认知发展方向与程度 ,也是应当考虑的一个重要因素。这就是说 ,至少应当综合社会因素与发展因素两个方面 ,来规定应有怎样的“学力”。本文简要分析日本和英国的学力理论的历史发展 ,并对“学力”概念作进一步的考察。 展开更多
关键词 学习理论 发展 日本 英国 学力理论 学力 学科教学
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建构与解构:大学生体育学力的理论基础及其层次——以汉江师范学院为考察中心 被引量:1
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作者 尹上 《汉江师范学院学报》 2021年第6期91-95,共5页
通过文献资料、调查访谈、逻辑分析等方法,建构大学生体育学力的理论基础,解构其层次.研究表明:大学生体育学力基本内容构成分为健身能力、认知与审美能力、自我实现能力,各能力构成具有层级结构.从低到高呈现金字塔结构,体现出大学生... 通过文献资料、调查访谈、逻辑分析等方法,建构大学生体育学力的理论基础,解构其层次.研究表明:大学生体育学力基本内容构成分为健身能力、认知与审美能力、自我实现能力,各能力构成具有层级结构.从低到高呈现金字塔结构,体现出大学生体育学力基础较薄弱,这为学力理论视野下大学体育课程改革提供了实证依据. 展开更多
关键词 学力理论 大学生体育学力 理论构建 体育学力层次
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“学力冰山理论”下的群文写作教学模式建构
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作者 吕松和 《语文教学通讯》 2020年第48期35-37,共3页
“学力冰山理论”强调人的才能和素质包括“水上部分”(可见部分)和“水下部分”(不可见部分),前者指向可通过学习得到的基本知识和基本技能,后者指向人的潜在能力和素质。而将此理论运用于初中写作教学后,可通过激发学生潜在写作兴趣... “学力冰山理论”强调人的才能和素质包括“水上部分”(可见部分)和“水下部分”(不可见部分),前者指向可通过学习得到的基本知识和基本技能,后者指向人的潜在能力和素质。而将此理论运用于初中写作教学后,可通过激发学生潜在写作兴趣、能力和天赋的方式建构“写作序列”,最终构成一个螺旋上升的写作训练体系。 展开更多
关键词 初中语文 学力冰山理论 群文写作 教学模式建构
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DYNAMICS ANALYSIS OF 2-DOF SPHERICAL PARALLEL MECHANISM 被引量:2
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作者 李成刚 王化明 朱剑英 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2009年第2期95-100,共6页
The analytical formulations of the velocity and the acceleration of a 2-DOF spherical parallel mechanism are derived by the screw theory. Based on building its dynamics model by the principle of virtual work and recip... The analytical formulations of the velocity and the acceleration of a 2-DOF spherical parallel mechanism are derived by the screw theory. Based on building its dynamics model by the principle of virtual work and reciprocal product of the screw, the equation of the motor moment is obtained. Through the transformation of dynamics model, the configuration space method of the dynamics equation and the corresponding coefficients are presented. Finally, the result of an example shows that the inertia moment and the gravity play a more important role than the coriolis and centrifugal moment, and the former is ten times of the latter in the magnitude. So, the latter can be neglected only when the velocity of mechanism is very slow. 展开更多
关键词 KINEMATICS MECHANICS dynamics analysis screw theory spherical parallel mechanism
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BUCKLING ANALYSIS OF WOVEN FABRIC UNDER SIMPLE SHEAR IN WARP DIRECTION 被引量:2
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作者 张义同 徐家福 《Transactions of Tianjin University》 EI CAS 2001年第1期36-39,共4页
Buckling of a woven fabric is analyzed in this paper when it is subjected to a simple shear in warp direction.The equation to determine the buckling direction (buckling wave direction) is obtained and it is found that... Buckling of a woven fabric is analyzed in this paper when it is subjected to a simple shear in warp direction.The equation to determine the buckling direction (buckling wave direction) is obtained and it is found that the buckling direction is related to the critical amount of shear.It is shown that the out-of-plane buckling of fabric is possible and only a flexural buckling mode can exist.The buckling condition for flexural mode is obtained and the curve for that is illustrated. 展开更多
关键词 fabric mechanics fabric buckling fabric constitutive theory
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Review on the Development of Oil and Gas Flow in Underground Porous Media 被引量:1
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作者 李军诗 王晓冬 +1 位作者 刘鹏程 侯晓春 《Petroleum Science》 SCIE CAS CSCD 2004年第4期88-94,共7页
Through reviewing the flow theory’s birth and development history in underground porous media and contrasting the mechanics of underground fluids and mechanics of viscous fluids, this paper points out the main facto... Through reviewing the flow theory’s birth and development history in underground porous media and contrasting the mechanics of underground fluids and mechanics of viscous fluids, this paper points out the main factors, which affect the development of the theory on oil and gas porous flow. The development law and development route of the mechanics of fluids in porous media are also summarized in this paper. 展开更多
关键词 Porous flow mechanics of fluids in porous media viscous fluids mechanics of ground water petroleum and natural gas engineering REVIEW PROGRESSION
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High Pressure Phase Stability of Ti with Self-consistent ab initio Lattice Dynamics Approach
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作者 曾召益 胡翠娥 +2 位作者 刘勋 张伟 蔡灵仓 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2015年第2期168-172,I0001,共6页
The traditional quasiharmonic approximation cannot predict the phase diagram of Ti accu- rately, due to the well-known soften phonon modes of the β-Ti. By means of self-consistent ab initio lattice dynamics (SCAILD... The traditional quasiharmonic approximation cannot predict the phase diagram of Ti accu- rately, due to the well-known soften phonon modes of the β-Ti. By means of self-consistent ab initio lattice dynamics (SCAILD) method, in which the effects of phonon-phonon in- teractions are considered, the phonon dispersion relations at finite temperature for Ti are calculated. From the phonon dispersions, we extrapolat the acoustic velocities and harmonic elastic constants. The dynamical stable regions and phase diagram of Ti are also predicted successfully. The results show that SCAILD method can be designed to work for strongly anharmonic systems where the QHA fails. 展开更多
关键词 Transition metal Lattice dynmnics Phase transition Density functionaltheory
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High Pressure Structural Instability and Thermal Properties of Rutile TiO2 from First-principles
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作者 胡翠娥 曾召益 +3 位作者 孔春阳 崔玉亭 张林 蔡灵仓 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第1期69-74,I0004,共7页
We report a first-principles calculation to investigate the structural instability of rutile TiO2. The high pressure structural parameters are well reproduced. The calculated phonon disper-sion curves agree with exper... We report a first-principles calculation to investigate the structural instability of rutile TiO2. The high pressure structural parameters are well reproduced. The calculated phonon disper-sion curves agree with experiments at zero pressure. Under compression, we capture a large softening around Γ point, which indicates the structural instability. From the high pressure elastic constants, we find that the rutile TiO2 is unstable when the applied pressure is larger than 17.7 GPa. Within the quasi-harmonic approximation, the thermal equation of state, thermal expansion oefficient, bulk modulus, and entropy are well reproduced. The thermal properties confirm the available experimental data and are extended to a wider pressure and temperature range. 展开更多
关键词 TiO2 Phonon dispersion THERMODYNAMICS Density functional theory
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Thermodynamic model of lead oxide activity in PbO-CaO-SiO_2-FeO-Fe_2O_3 slag system
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作者 汪金良 温小椿 张传福 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第5期1633-1639,共7页
According to the ion and molecule coexistence theory, a thermodynamic model of lead oxide activity in PbO-CaO-SiO2-FeO-Fe2O3 slag system was established at the temperature of 1273-1733 K. The activities of Pb O in sla... According to the ion and molecule coexistence theory, a thermodynamic model of lead oxide activity in PbO-CaO-SiO2-FeO-Fe2O3 slag system was established at the temperature of 1273-1733 K. The activities of Pb O in slag were calculated, and their equal activity curves were plotted. The influences of slag basicity Q, iron oxide rate R and temperature T on activity NPb O and activity coefficient γPbO were also investigated. Results show that the calculated values of γPb O are in good agreement with the reported experimental data, showing that the model can wholly embody the slag structural characteristics. NPbO departures positively from Raoult values, and increases with increasing Pb O content in slag but changes little with T. γPbO increases with increasing Q, and goes through the maximum with increasing R for basic slag(Q0.3). Results can be applied to the thermodynamic research and operational optimization of modern lead smelting technologies. 展开更多
关键词 ion and molecule coexistence theory thermodynamic model lead oxide ACTIVITY
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Atomistic simulation of defected magnesium hydroxide as flame retardants
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作者 张冬云 杨萍 +4 位作者 都政 袁秋华 宋申华 任祥忠 张培新 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第12期4080-4088,共9页
The mechanical properties and the point defect energy of magnesium hydroxide(Mg(OH)2) were studied using the molecular dynamics. Moreover, the microelectronic structure of Mg(OH)2 with point defects in the bulk ... The mechanical properties and the point defect energy of magnesium hydroxide(Mg(OH)2) were studied using the molecular dynamics. Moreover, the microelectronic structure of Mg(OH)2 with point defects in the bulk and on its surface were investigated using the first principles. The simulation results indicate that Mg(OH)2 was easily modified by other cations because of its strong, favorable interstitial and substitution defects via point defect energy calculation. Mg(OH)2 can provide high-efficiency flame retardancy because of the strong OH(OH Schottky defect) or H bond(H Frenkel defect and Schottky defect). The potential model of Mg(OH)2 was established, and molecular dynamics simulation was used to investigate the relations between the crystal structure and the mechanical properties. Mg(OH)2 with special morphology such as nano-sheets was a prior consideration to maintain the composite mechanical properties. The detailed electronic structures of Mg(OH)2 with defects were determined. This work may provide theoretical guidance for choosing dopant element and reveal the element doping mechanism of Mg(OH)2. 展开更多
关键词 Mg(OH)2 density functional theory molecular dynamics DEFECTS electronic structure
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Representation Theory of Three-Dimensional Elliptical Crack Under Dynamic Loading
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作者 范天佑 《Journal of Beijing Institute of Technology》 EI CAS 2000年第2期138-141,共4页
The relation between the normal displacement on the surface of a dynamical elliptical crack and the normal stress over the crack surface was studied. The three dimensional elastodynamic equations and Fourier Laplace... The relation between the normal displacement on the surface of a dynamical elliptical crack and the normal stress over the crack surface was studied. The three dimensional elastodynamic equations and Fourier Laplace transforms are used. Based on the influence function and the inversion of integral transforms, one can find that if the distribution of normal displacement on the surface of a dynamic elliptical crack is a polynomial of degree n in x 1 and x 2 , then the normal pressure acting over the ellipse is also a polynomial P n(x 1,x 2) of the same degree in x 1 and x 2 . 展开更多
关键词 dynamic elliptical crack ELASTODYNAMICS integral transforms representation theory
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Anisotropy of Thermal-expansion for β-Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine: Quantum Chemistry Calculation and Molecular Dynamics Simulation
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作者 钱文 张朝阳 +3 位作者 舒远杰 熊鹰 宗和厚 张伟斌 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第1期57-62,I0003,共7页
Molecular dynamics simulations on octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) at 303-383 K and atmospheric pressure are carried out under NPT ensemble and COMPASS force field, the equilibrium structures a... Molecular dynamics simulations on octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) at 303-383 K and atmospheric pressure are carried out under NPT ensemble and COMPASS force field, the equilibrium structures at elevated temperatures were obtained and showed that the stacking style of molecules don't change. The coefficient of thermal expansion (CTE) values were calculated by linear fitting method. The results show that the CTE values are close to the experimental results and show anisotropy. The total energies of HMX cells with separately increasing expansion rates (100%-105%) along each crystallographic axis was calculated by periodic density functional theory method, the results of the energy change rates are anisotropic, and the correlation equations of energy change-CTE values are established. Thus the hypostasis of the anisotropy of HMX crystal's thermal expansion, the determinate molecular packing style, is elucidated. 展开更多
关键词 Octahydro-1 3 5 7-tetranitro-1 3 5 7-tetrazocine Molecular dynamics simula-tion Thermal expansion ANISOTROPY Density functional theory
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On the mode of CRI English assisting college English teaching
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作者 纪鸿 《Sino-US English Teaching》 2007年第5期70-73,共4页
The English News of CRI possesses many advantages such as abundance of information and being easily accessible for English learners within the mainland of China. Unfortunately, it has been ignored by most teachers of ... The English News of CRI possesses many advantages such as abundance of information and being easily accessible for English learners within the mainland of China. Unfortunately, it has been ignored by most teachers of English and students. Based on the input hypothesis, affective filter hypothesis and schemata theory, this paper probes the mode of CRI English assisting English teaching in college. 展开更多
关键词 input hypothesis affective filter hypothesis schemata CRI listening teaching
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Recent advances in micro-alloyed wrought magnesium alloys:Theory and design 被引量:13
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作者 Bin JIANG Zhi-hua DONG +2 位作者 Ang ZHANG Jiang-feng SONG Fu-sheng PAN 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第6期1741-1780,共40页
Micro-alloying design of wrought magnesium(Mg) alloys is an important strategy to achieve high mechanical properties at a low cost. In the last two decades, significant progress has been made from both theory and expe... Micro-alloying design of wrought magnesium(Mg) alloys is an important strategy to achieve high mechanical properties at a low cost. In the last two decades, significant progress has been made from both theory and experiment. In the present review, we try to summarize recent advances in micro-alloying design of wrought Mg alloys from both theoretical and pragmatic perspectives, and provide fundamental data required for establishing the relationship between chemical composition and mechanical properties of Mg alloys. We start with theoretical attempts for understanding the mechanical properties of Mg alloys at different scales, by involving first principle calculations,molecular dynamics, cellular automata, and crystal plasticity. Then, the role of alloying elements is discussed for a series of promising Mg alloys such as Mg-Al, Mg-Zn, Mg-RE(rare-earth element), Mg-Sn, and Mg-Ca families.Potential challenges in the micro-alloying design of Mg alloys are highlighted at the end. The review is expected to provide helpful guidance for the intelligent design of novel wrought Mg alloys and inspire more innovative ideas in this field. 展开更多
关键词 magnesium alloys alloying design mechanical properties theoretical calculations experimental characterizations
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Numerical simulation of the effect of coupling support of bolt-mesh-anchor in deep tunnel 被引量:18
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作者 SUN Xiao-ming CAI Feng +1 位作者 YANG Jun CAO Wu-fu 《Mining Science and Technology》 EI CAS 2009年第3期352-357,共6页
The mechanical effects of bolt-mesh-anchor coupling support in deep tunnels were studied by using a numerical method, based on deep tunnel coupling supporting techniques and non-linear deformation mechanical theory of... The mechanical effects of bolt-mesh-anchor coupling support in deep tunnels were studied by using a numerical method, based on deep tunnel coupling supporting techniques and non-linear deformation mechanical theory of rock mass at great depths.It is shown that the potential of a rigid bolt support can be efficiently activated through the coupling effect between a bolt-net support and the surrounding rock.It is found that the accumulated plastic energy in the surrounding rock can be sufficiently transformed by the coupling effect of a bolt-mesh-tray support.The strength of the surrounding rock mass can be mobilized to control the deforma-tion of the surrounding rock by a pre-stress and time-space effect of the anchor support.The high stress transformation effect can be realized by the mechanical coupling effect of the bolt-mesh-anchor support, whereby the force of the support and deformation of the surrounding rock tends to become uniform, leading to a sustained stability of the tunnel. 展开更多
关键词 mining engineering deep tunnel non-linear large deformation mechanics bolt-mesh-anchor support coupling support effect
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Remote Preparation of Three-Particle GHZ Class States 被引量:2
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作者 LIU Yi-Min WANG Zhang-Yin +1 位作者 LIU Jun ZHANG Zhan-Jun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第2期359-364,共6页
We propose a remote state preparation (RSP) scheme of three-particle Greenberger Horne-Zeilinger (GHZ) class states, where quantum channels are composed of two maximally entangled states. With the aid of forward c... We propose a remote state preparation (RSP) scheme of three-particle Greenberger Horne-Zeilinger (GHZ) class states, where quantum channels are composed of two maximally entangled states. With the aid of forward classical bits, the preparation of the original state can be successfully realized with the probability 1/2, the necessary classical communication cost is 0.5 bit on average. If the state to be prepared belongs to some special states, the success probability of preparation can achieve 1 after consuming one extra bit on average. We then generalize this scheme to the case that the quantum channels consist of two non-maximally entangled states. 展开更多
关键词 remote state preparation entangled states classical communication cost two-qubit projective measurement unitary operation
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Theoretical analysis on water-inrush mechanism of concealed collapse pillars in floor 被引量:12
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作者 Tang Junhua Bai Haibo +1 位作者 Yao Banghua WU YU 《Mining Science and Technology》 EI CAS 2011年第1期57-60,共4页
In order to study the water-inrush mechanism of concealed collapse pillars from the mechanical view, a mechanical model for water-inrush of collapse pillars has been established based on thick plate theory of elastic ... In order to study the water-inrush mechanism of concealed collapse pillars from the mechanical view, a mechanical model for water-inrush of collapse pillars has been established based on thick plate theory of elastic mechanics in this paper.By solving this model the deformation of water-resistant rock strata under the action of water pressure and the expression of critical water pressure for collapse pillar waterinrush have been obtained The research results indicate that:the boundary conditions and strength of water-resistant strata play important roles in influencing water-inrush of collapse pillars.The critical water-inrush pressure is determined by both relative thickness and absolute thickness of water-resistant strata. 展开更多
关键词 Collapse pillar Water-inrush Critical water pressure Thick plate theory
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Vertical vibration of a large diameter pipe pile considering transverse inertia effect of pile 被引量:10
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作者 郑长杰 刘汉龙 +1 位作者 丁选明 周航 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第4期891-897,共7页
Considering the transverse inertia effect of pile, the vertical soil layer is studied. The wave propagations in the outer and inner soil dynamic response of a large diameter pipe pile in viscoelastic are simulated by ... Considering the transverse inertia effect of pile, the vertical soil layer is studied. The wave propagations in the outer and inner soil dynamic response of a large diameter pipe pile in viscoelastic are simulated by three-dimensional elastodynamic theory and those in the pile are simulated by Rayleigh-Love rod theory. The vertical and radial displacements of the outer and inner soil are obtained by utilizing Laplace transform technique and differentiation on the governing equations of soils. Then, based on the continuous conditions between the pile and soils, the displacements of the pile are derived. The frequency domain velocity admittance and time domain velocity response of the pile top are also presented. The solution is compared to a classical rod model solution to verify the validity. The influences of the radii and Poisson ratio of pile on the transverse inertia effect of pile are analyzed. The parametric study shows that Poisson ratio and outer radius of pile have significant influence on the transverse inertia effect of large diameter pipe piles, while the inner radius has little effect. 展开更多
关键词 large diameter pipe pile vertical vibration Rayleigh-Love rod transverse inertia effect
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Mechanical genesis of Henan(China) Yima thrust nappe structure 被引量:2
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作者 蔡武 窦林名 +3 位作者 何江 刘海顺 李振雷 丁言露 《Journal of Central South University》 SCIE EI CAS 2014年第7期2857-2865,共9页
Considering the serious coal and rock dynamic disasters around the main slip plane called F16 in the coal mining area) of Henan Yima(China) thrust nappe structure,the mechanical genesis of the Yima thrust nappe struct... Considering the serious coal and rock dynamic disasters around the main slip plane called F16 in the coal mining area) of Henan Yima(China) thrust nappe structure,the mechanical genesis of the Yima thrust nappe structure was studied comprehensively using geomechanics,fault mechanics,elastic mechanics,and Coulomb's law of friction.First,using the centrifugal inertia force of Earth's rotation as a source,a mechanical model of N-S compression superimposed with W-E reverse torsion was established to explain the formation of the early Yima coal basin and Jurassic Yima Group coal measures.Second,an equation for the ultimate stress in the forming stage of F16 was derived using the plastic slip-line field theory and the parabolic Mohr failure criterion.Moreover,the distribution of ultimate stress and the geometric characteristics of the fault profile were obtained using the field model parameters.Finally,the stress field of F16 and the mechanical genesis of the large-scale reverse thrust sheet were discussed based on elastic mechanics theory and Coulomb's law of friction.The results show that the tectonic framework of the early Yima coal basin and the formation pattern of Jurassic Yima Group coal measures given by the model are consistent with the in-situ explorations.The geometric characteristics of the fault profile obtained by numerical calculation can better reflect the shape of F16 in its forming stage,and the mechanical genesis of the large-scale reverse thrust sheet also concurred with the field situations.Thus,this work can provide a foundation for further studies on the genesis of the thrust nappe structure,the mechanism of rock bursts induced by F16,and the characteristics of the residual stress field in the Yima mining area. 展开更多
关键词 mechanical genesis thrust nappe structure centrifugal inertia force fault mechanics slip-line field theory Coulomb's law of friction
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