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Methods of analytical mechanics for solving differential equations of first order 被引量:5
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作者 吴惠彬 梅凤翔 《Chinese Physics B》 SCIE EI CAS CSCD 2005年第12期2391-2394,共4页
A differential equation of first order can be expressed by the equation of motion of a mechanical system. In this paper, three methods of analytical mechanics, i.e. the Hamilton-Noether method, the Lagrange-Noether me... A differential equation of first order can be expressed by the equation of motion of a mechanical system. In this paper, three methods of analytical mechanics, i.e. the Hamilton-Noether method, the Lagrange-Noether method and the Poisson method, are given to solve a differential equation of first order, of which the way may be called the mechanical methodology in mathematics. 展开更多
关键词 analytical mechanics differential equation Noether theory Poisson method
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Efficient and rapid accuracy estimation of the Earth's gravitational field from next-generation GOCE Follow-On by the analytical method 被引量:4
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作者 郑伟 许厚泽 +2 位作者 钟敏 刘成恕 员美娟 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第4期563-570,共8页
Firstly, a new analytical error model of the cumulative geoid height using the three-dimensional diagonal tensors of satellite gravity gradiometry (SGG) is introduced based on the variance-covariance matrix principl... Firstly, a new analytical error model of the cumulative geoid height using the three-dimensional diagonal tensors of satellite gravity gradiometry (SGG) is introduced based on the variance-covariance matrix principle. Secondly, a study for the requirements demonstration on the next-generation GOCE Follow-On satellite gravity gradiometry system is developed using different satellite orbital altitudes and measurement accuracies of satellite gravity gradiometer by the new analytical error model of SGG. The research results show that it is preferable to design satellite orbital altitudes of 300 km–400km and choose the measurement accuracies of 10-13/s2 –10-15/s2 from satellite gravity gradiometer. Finally, the complementarity of the four-stage satellite gravity missions, including past CHAMP, current GRACE, and GOCE, and next-generation GOCE Follow-On, is contrastively demonstrated for precisely recovering the Earth’s full-frequency gravitational field with high spatial resolution. 展开更多
关键词 GOCE Follow-On satellite analytical method requirements demonstration satellite gravity gradiometry Earth’s gravitational field
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High-pressure phonon dispersion of copper by using the modified analytic embedded atom method 被引量:2
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作者 张晓军 陈长乐 凤飞龙 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第9期520-524,共5页
By using the Born-von Kfirmfin theory of lattice dynamics and the modified analytic embedded atom method, we reproduce the experimental results of the phonon dispersion in fcc metal Cu at zero pressure along three hig... By using the Born-von Kfirmfin theory of lattice dynamics and the modified analytic embedded atom method, we reproduce the experimental results of the phonon dispersion in fcc metal Cu at zero pressure along three high symmetry directions and four oft-symmetry directions, and then simulate the phonon dispersion curves of Cu at high pressures of 50, 100, and 150 GPa. The results show that the shapes of dispersion curves at high pressures are very similar to that at zero pressure. All the vibration frequencies of Cu in all vibration branches at high pressures are larger than the results at zero pressure, and increase correspondingly as pressure reaches 50, 100, and 150 GPa sequentially. Moreover, on the basis of phonon dispersion, we calculate the values of specific heat of Cu at different pressures. The prediction of thermodynamic quantities lays a significant foundation for guiding and judging experiments of thermodynamic properties of solids under high pressures. 展开更多
关键词 phonon dispersion high pressure SIMULATION modified analytic embedded atom method
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Analysis profile of the fully grouted rock bolt in jointed rock using analytical and numerical methods 被引量:5
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作者 Ghadimi Mostafa Shahriar Kourosh Jalalifar Hossein 《International Journal of Mining Science and Technology》 SCIE EI 2014年第5期609-615,共7页
The purpose of this study was to investigate the effect of bolt profile on load transfer mechanism of fully grouted bolts in jointed rocks using analytical and numerical methods. Based on the analytical method with de... The purpose of this study was to investigate the effect of bolt profile on load transfer mechanism of fully grouted bolts in jointed rocks using analytical and numerical methods. Based on the analytical method with development of methods, a new model is presented. To validate the analytical model, five different profiles modeled by ANSYS software. The profile of rock bolts T3 and T4with load transfer capacity,respectively 180 and 195 kN in the jointed rocks was selected as the optimum profiles. Finally, the selected profiles were examined in Tabas Coal Mine. FLAC analysis indicates that patterns 6+7 with2 NO flexi bolt 4 m better than other patterns within the faulted zone. 展开更多
关键词 Fully grouted bolt Load transfer mechanism Jointed rocks analytical and numerical methods
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Homogenous Balance Method and Exact Analytical Solutions for Whitham-Broer-Kaup Equations in Shallow Water 被引量:1
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作者 XIAZhi 《Chinese Quarterly Journal of Mathematics》 CSCD 2004年第3期240-246,共7页
Based on the homogenous balance method and with the help of mathematica, the Backlund transformation and the transfer heat equation are derived. Analyzing the heat-transfer equation, the multiple soliton solutions and... Based on the homogenous balance method and with the help of mathematica, the Backlund transformation and the transfer heat equation are derived. Analyzing the heat-transfer equation, the multiple soliton solutions and other exact analytical solution for Whitham-Broer-Kaup equations(WBK) are derived. These solutions contain Fan's, Xie's and Yan's results and other new types of analytical solutions, such as rational function solutions and periodic solutions. The method can also be applied to solve more nonlinear differential equations. 展开更多
关键词 improved homogenous balance method Backlund transformation solitary wave solution multiple solution exact analytical solution rational solution
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General analytical method of designing shielded coils for arbitrary axial magnetic field
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作者 Yi Zhang Yu-Jiao Li +3 位作者 Qi-Yuan Jiang Zhi-Guo Wang Tao Xia and Hui Luo 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第11期134-139,共6页
Magnetic coils for specific requirements are widely used in modern quantum physics. In this study, a general analytical method of designing the shielded coils for generating an arbitrary axial magnetic field is propos... Magnetic coils for specific requirements are widely used in modern quantum physics. In this study, a general analytical method of designing the shielded coils for generating an arbitrary axial magnetic field is proposed. The theoretical formula for an axial magnetic field generated by a single shielded coil is obtained and used to construct specific coils. The structural parameters of these coils are determined by fitting the theoretical formula with their specific requirements. The feasibility of this method is proved by realizing four concrete kinds of coils: uniform magnetic field generating coils, gradient magnetic field generating coils, asymmetrical uniform magnetic field generating coils, and parabolic magnetic field generating coils. The correctness of these theoretical results is demonstrated by both the finite element simulations and the relevant experimental results. Furthermore, the application of this method is of great significance for developing the quantum physics and quantum devices in future. 展开更多
关键词 MAGNETIC coils analyticAL method SHIELDING QUANTUM DEVICE
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Energy eigenvalues from an analytical transfer matrix method
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作者 何英 张凡明 +1 位作者 杨艳芳 李春芳 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第4期50-55,共6页
A detailed procedure based on an analytical transfer matrix method is presented to solve bound-state problems. The derivation is strict and complete. The energy eigenvalues for an arbitrary one-dimensional potential c... A detailed procedure based on an analytical transfer matrix method is presented to solve bound-state problems. The derivation is strict and complete. The energy eigenvalues for an arbitrary one-dimensional potential can be obtained by the method. The anharmonic oscillator potential and the rational potential are two important examples. Checked by numerical techniques, the results for the two potentials by the present method are proven to be exact and reliable. 展开更多
关键词 analytical transfer matrix method energy eigenvalues bound state one-dimensional potential
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The analytical transfer matrix method for quantum reflection
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作者 许田 曹庄琪 方靖淮 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第4期56-61,共6页
In this paper, the analytical transfer matrix method (ATMM) is applied to study the properties of quantum reflection in three systems: a sech2 barrier, a ramp potential and an inverse harmonic oscillator. Our resul... In this paper, the analytical transfer matrix method (ATMM) is applied to study the properties of quantum reflection in three systems: a sech2 barrier, a ramp potential and an inverse harmonic oscillator. Our results agree with those obtained by Landau and Lifshitz [Landau L D and Lifshitz E M 1977 Quantum Mechanics (Non-relativistic Theory) (New York: Pergamon)], which proves that ATMM is a simple and effective method for quantum reflection. 展开更多
关键词 analytical transfer matrix method quantum reflection reflection coemcient transmission coefficient reflection time
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An analytical variational method for the biased quantum Rabi model in the ultra-strong coupling regime
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作者 Bin-Bin Mao Maoxin Liu +3 位作者 Wei WU Liangsheng Li Zu-Jian Ying Hong-Gang Luo 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第5期322-327,共6页
An analytical variational method for the ground state of the biased quantum Rabi model in the ultra-strong coupling regime is presented. This analytical variational method can be obtained by a unitary transformation o... An analytical variational method for the ground state of the biased quantum Rabi model in the ultra-strong coupling regime is presented. This analytical variational method can be obtained by a unitary transformation or alternatively by assuming the form of the ground state wave function. The key of the method is to introduce a variational parameter λ,which can be determined by minimizing the energy functional. Using this method, we calculate the physical observables with high accuracy in comparison with the numerical exact ones. Our method evidently improves over the widely used general rotating-wave approximation(GRWA) in both qualitative and quantitative aspects. 展开更多
关键词 ultra-strong coupling biased quantum Rabi model analytical variational method
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Assessment of Effects of Green Construction by Analytic Hierarchy Process and Fuzzy Synthetic Judgment Method
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作者 申琪玉 李惠强 《Journal of Southwest Jiaotong University(English Edition)》 2008年第3期260-265,共6页
The index system, code system, and weights of indexes are established to assess the effects of green construction. The index system consists of index level, factor level and sub-factor level. The analytic hierarchy pr... The index system, code system, and weights of indexes are established to assess the effects of green construction. The index system consists of index level, factor level and sub-factor level. The analytic hierarchy process is used to determine the weights of indexes, and the consistency test indicate that the weight assignment is reasonable. Using fuzzy synthetic judgment method, the assessment model is built, which includes factor set, weight set and conclusion set. An example is given to demonstrate the assessment procedures. 展开更多
关键词 Green construction Assessment system analytic hierarchy process Fuzzy synthetic judgment method
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Approximation analytical solutions for a unified plasma sheath model by double decomposition method
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作者 Fang Jin-Qing (China Institute of Atomic Energy Beijing 102413) 《Nuclear Science and Techniques》 SCIE CAS CSCD 1998年第4期193-197,共5页
A anified plasma sheath model and its potential equation are proposed. Any higher-ordor-approximation analytical solutions for the unified plasma sheath potential equa tiop are derived by double decomposition method.
关键词 等离子体 屏蔽模型 双分解方法 近似分析
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Analytic Study on a Plane Stress Tensile Crack in a Power-Law Hardening Material
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作者 王文信 张良欣 范天佑 《Journal of Beijing Institute of Technology》 EI CAS 1998年第3期252-256,共5页
Aim To construct an analytic solution for the asymptotic field near a tensile cracktip of power-law hardening material under Plane stress condition. Methods Constructing funtion method was used. Results The exact as... Aim To construct an analytic solution for the asymptotic field near a tensile cracktip of power-law hardening material under Plane stress condition. Methods Constructing funtion method was used. Results The exact asymptotic field was found. Conclusion The exact analytic solution for the problem is available. 展开更多
关键词 power-law hardening plane stress constructing function method analytic solution
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Accurate ab initio-based analytical potential energy function for S_2(~1△_g) via extrapolation to the complete basis set limit 被引量:1
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作者 张路路 高守宝 +1 位作者 孟庆田 宋玉志 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第1期201-207,共7页
The potential energy curves(PECs) of the first electronic excited state of S2(a^1△g) are calculated employing a multi-reference configuration interaction method with the Davidson correction in combination with a ... The potential energy curves(PECs) of the first electronic excited state of S2(a^1△g) are calculated employing a multi-reference configuration interaction method with the Davidson correction in combination with a series of correlationconsistent basis sets from Dunning: aug-cc-p VX Z(X = T, Q, 5, 6). In order to obtain PECs with high accuracy, PECs calculated with aug-cc-p V(Q, 5)Z basis sets are extrapolated to the complete basis set limit. The resulting PECs are then fitted to the analytical potential energy function(APEF) using the extended Hartree–Fock approximate correlation energy method. By utilizing the fitted APEF, accurate and reliable spectroscopic parameters are obtained, which are consistent with both experimental and theoretical results. By solving the Schr o¨dinger equation numerically with the APEFs obtained at the AV6 Z and the extrapolated AV(Q, 5)Z level of theory, we calculate the complete set of vibrational levels, classical turning points, inertial rotation and centrifugal distortion constants. 展开更多
关键词 multi-reference configuration interaction method(MRCI) analytical potential energy functions vibrational levels spectroscopic parameters
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Approximate analytic solutions for a generalized Hirota—Satsuma coupled KdV equation and a coupled mKdV equation
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作者 赵国忠 蔚喜军 +2 位作者 徐云 朱江 吴迪 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第8期46-54,共9页
This paper applies the variational iteration method to obtain approximate analytic solutions of a generalized Hirota-Satsuma coupled Korteweg-de Vries (KdV) equation and a coupled modified Korteweg-de Vries (mKdV)... This paper applies the variational iteration method to obtain approximate analytic solutions of a generalized Hirota-Satsuma coupled Korteweg-de Vries (KdV) equation and a coupled modified Korteweg-de Vries (mKdV) equation. This method provides a sequence Of functions which converges to the exact solution of the problem and is based on the use of Lagrange multiplier for identification of optimal values of parameters in a functional. Some examples are given to demonstrate the reliability and convenience of the method and comparisons are made with the exact solutions. 展开更多
关键词 approximate analytic solutions generalized Hirota-Satsuma coupled KdV equation coupled mKdV equation variational iteration method
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A full-dimensional analytical potential energy surface for the F+CH_4→HF+CH_3 reaction
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作者 杨传路 王美山 +2 位作者 刘文旺 张志红 马晓光 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第6期314-321,共8页
A full-dimensional analytical potential energy surface (APES) for the F + CH4 →HF + CH3 reaction is developed based on 7127 ab initio energy points at the unrestricted coupled-cluster with single, double, and per... A full-dimensional analytical potential energy surface (APES) for the F + CH4 →HF + CH3 reaction is developed based on 7127 ab initio energy points at the unrestricted coupled-cluster with single, double, and perturbative triple excitations. The correlation-consistent polarized triple-split valence basis set is used. The APES is represented with a many-body expansion containing 239 parameters determined by the least square fitting method. The two-body terms of the APES are fitted by potential energy curves with multi-reference configuration interaction, which can describe the diatomic molecules (CH, H2, HF, and CF) accurately. It is found that the APES can reproduce the geometry and vibrational frequencies of the saddle point better than those available in the literature. The rate constants based on the present APES support the experimental results of Moore et al. [Int. J. Chem. Kin. 26, 813 (1994)]. The analytical first-order derivation of energy is also provided, making the present APES convenient and efficient for investigating the title reaction with quasiclassical trajectory calculations. 展开更多
关键词 analytical potential energy surface least square fitting method UCCSD(T) F CH4 →HF CH3reaction
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Analytical solution of crystal diffraction intensity
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作者 Wan-Li Shang Ao Sun +13 位作者 Hua-Bin Du Guo-Hong Yang Min-Xi Wei Xu-Fei Xie Xing-Sen Che Li-Fei Hou Wen-Hai Zhang Miao Li Jun Shi Feng Wang Hai-En He Jia-Min Yang Shao-En Jiang Bao-Han Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第11期430-433,共4页
Plasma density and temperature can be diagnosed by x-ray line emission measurement with crystal,and bent crystals such as von Hamos and Hall structures are proposed to improve the diffraction brightness.In this study,... Plasma density and temperature can be diagnosed by x-ray line emission measurement with crystal,and bent crystals such as von Hamos and Hall structures are proposed to improve the diffraction brightness.In this study,a straightforward solution for the focusing schemes of flat and bent crystals is provided.Simulations with XOP code are performed to validate the analytical model,and good agreements are achieved.The von Hamos or multi-cone crystal can lead to several hundred times intensity enhancements for a 200μm plasma source.This model benefits the applications of the focusing bent crystals. 展开更多
关键词 crystal diffraction analytic method x-ray diffraction
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Estimation of Rolling Motion of Ship in Random Beam Seas by Efficient Analytical and Numerical Approaches
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作者 M.Salai Mathi Selvi L.Rajendran Marwan Abukhaled 《Journal of Marine Science and Application》 CSCD 2021年第1期55-66,共12页
A steady-state roll motion of ships with nonlinear damping and restoring moments for all times is modeled by a second-order nonlinear differential equation.Analytical expressions for the roll angle,velocity,accelerati... A steady-state roll motion of ships with nonlinear damping and restoring moments for all times is modeled by a second-order nonlinear differential equation.Analytical expressions for the roll angle,velocity,acceleration,and damping and restoring moments are derived using a modified approach of homotopy perturbation method(HPM).Also,the operational matrix of derivatives of ultraspherical wavelets is used to obtain a numerical solution of the governing equation.Illustrative examples are provided to examine the applicability and accuracy of the proposed methods when compared with a highly accurate numerical scheme. 展开更多
关键词 Nonlinear damping Steady-state roll motion Ultraspherical wavelets Homotopy perturbation method analytical solution
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SOME ANALYTIC PROBLEMS FOR CLEAN FUEL PRODUCTION
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作者 TIAN Song bai (Research Institute of Petroleum Processing, SINOPEC, Beijing 100083, China) 《石油学报(石油加工)》 EI CAS CSCD 北大核心 2003年第1期84-88,共5页
Sulfur contents olefins, aromatics, octane number and cetane number are very important indicators of clean fuel. The analytical methods of these indicators proposed by Research Institute of Petroleum Processing (RIPP)... Sulfur contents olefins, aromatics, octane number and cetane number are very important indicators of clean fuel. The analytical methods of these indicators proposed by Research Institute of Petroleum Processing (RIPP) were introduced in this article. These methods possess the advantages of fast, convenient and precise, and have been used in R&D work and production process control as well. 展开更多
关键词 清洁燃料 含硫量 烯烃 芳香烃 辛烷值
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压缩空气储能电站地下内衬硐库基本原理与分析方法研究进展 被引量:1
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作者 孙冠华 王娇 +5 位作者 于显杨 易琪 朱开源 王章星 耿璇 屈杰 《岩土力学》 北大核心 2025年第1期1-25,共25页
地下内衬硐库的压缩空气储能,以其发电时间长、规模大、建设周期短、选址灵活、工程造价低、运行周期长、环境友好等优势,在新型储能领域展现了较强的生命力,将有力地促进新型电力系统的构建和新能源的高质量发展。与传统地下空间的运... 地下内衬硐库的压缩空气储能,以其发电时间长、规模大、建设周期短、选址灵活、工程造价低、运行周期长、环境友好等优势,在新型储能领域展现了较强的生命力,将有力地促进新型电力系统的构建和新能源的高质量发展。与传统地下空间的运行特点有较大不同,在充放气过程中,储备有压缩空气的地下内衬硐库不仅需要承受交变高内压膨胀压力,同时伴随着显著的温度变化。围绕地下内衬硐库,阐述了其工作原理以及柔性密封结构的设计理念,针对高压、交变应力和温度变化等荷载特征,系统分析了地下内衬硐库相关理论与分析方法等方面的研究进展,主要包括库内温压响应与密封结构传热特性、围岩应力路径与力学响应、钢筋混凝土衬砌开裂与控制标准、上覆岩体稳定性与安全埋深、密封层及密封堵头等,并对地下内衬硐库基本原理与分析方法的发展趋势进行了展望。 展开更多
关键词 压缩空气储能 岩石内衬硐库 分析方法
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列车荷载作用下的磁浮轨道梁响应极值条件
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作者 向活跃 刘科宏 李永乐 《西南交通大学学报》 北大核心 2025年第1期27-34,136,共9页
为研究磁浮轨道梁动力响应的变化规律,将磁浮列车简化为移动的均布荷载,采用解析法得到简支轨道梁动力响应的解析解,并讨论轨道梁最大值随车速、跨度等参数的变化规律,推导磁浮轨道梁动力响应的极值条件,利用有限元方法和车-桥耦合振动... 为研究磁浮轨道梁动力响应的变化规律,将磁浮列车简化为移动的均布荷载,采用解析法得到简支轨道梁动力响应的解析解,并讨论轨道梁最大值随车速、跨度等参数的变化规律,推导磁浮轨道梁动力响应的极值条件,利用有限元方法和车-桥耦合振动方法进行验证.结果表明:列车与轨道梁跨度比值较大时,随列车速度的增加轨道梁跨中最大响应以波动形式增加,最大响应存在极值,轨道梁响应随轨道梁跨度、质量等参数也有类似规律;当车速和跨度的乘积为特定常数,或轨道梁一阶竖弯频率与跨度的乘积为车速特定倍数时,轨道梁产生消振现象. 展开更多
关键词 磁浮轨道梁 动力响应 均布荷载 解析法 消振现象
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