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基于蒙特卡洛法的Euler-Bernoulli梁基频和振型求解方法
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作者 祝磊 张建勋 孙海林 《Journal of Southeast University(English Edition)》 EI CAS 2024年第2期203-209,共7页
将Rayleigh法和蒙特卡洛法相结合,在Euler-Bernoulli梁理论假设下求解了均匀梁、变截面梁和附带集中质量的变截面梁自由振动问题.对原本连续的梁结构模型进行离散化处理,利用蒙特卡洛法给出梁结构的假设振型.将假设得到的梁结构振型函... 将Rayleigh法和蒙特卡洛法相结合,在Euler-Bernoulli梁理论假设下求解了均匀梁、变截面梁和附带集中质量的变截面梁自由振动问题.对原本连续的梁结构模型进行离散化处理,利用蒙特卡洛法给出梁结构的假设振型.将假设得到的梁结构振型函数代入Rayleigh法,多次计算过程中,将历次基频所得值与计算所得最小值进行比较,根据其相对误差判断是否满足收敛条件,进而求得基频及对应的振型.结果表明,不同计算模型中基频最大误差不超过10%,能够满足工程需求,且精度和时间的控制参数调整灵活,使用者可根据自身需要自行调节.该方法理论简明,适用范围广泛,能够快速准确地求解诸多类型的梁结构基频和振型. 展开更多
关键词 euler-BERNOULLI梁 基频 蒙特卡洛法 数值解
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Analysis of regular and chaotic dynamics of the Euler-Bernoulli beams using finite difference and finite element methods 被引量:3
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作者 J.Awrejcewicz A.V.Krysko +2 位作者 J.Mrozowski O.A.Saltykova M.V.Zhigalov 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2011年第1期36-43,共8页
Chaotic vibrations of flexible non-linear Euler-Bernoulli beams subjected to harmonic load and with various boundary conditions(symmetric and non-symmetric)are studied in this work.Reliability of the obtained result... Chaotic vibrations of flexible non-linear Euler-Bernoulli beams subjected to harmonic load and with various boundary conditions(symmetric and non-symmetric)are studied in this work.Reliability of the obtained results is verified by the finite difference method(FDM)and the finite element method(FEM)with the Bubnov-Galerkin approximation for various boundary conditions and various dynamic regimes(regular and non-regular).The influence of boundary conditions on the Euler-Bernoulli beams dynamics is studied mainly,dynamic behavior vs.control parameters { ωp,q0 } is reported,and scenarios of the system transition into chaos are illustrated. 展开更多
关键词 euler-Bernoulli beams · Chaos · Finite differ-ence method · Finite element method
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Artificial boundary conditions for Euler–Bernoulli beam equation 被引量:1
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作者 Shao-Qiang Tang Eduard G.Karpov 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2014年第5期687-692,共6页
In a semi-discretized Euler-Bernoulli beam equa- tion, the non-nearest neighboring interaction and large span of temporal scales for wave propagations pose challenges to the effectiveness and stability for artificial ... In a semi-discretized Euler-Bernoulli beam equa- tion, the non-nearest neighboring interaction and large span of temporal scales for wave propagations pose challenges to the effectiveness and stability for artificial boundary treat- ments. With the discrete equation regarded as an atomic lattice with a three-atom potential, two accurate artificial boundary conditions are first derived here. Reflection co- efficient and numerical tests illustrate the capability of the proposed methods. In particular, the time history treatment gives an exact boundary condition, yet with sensitivity to nu- merical implementations. The ALEX (almost EXact) bound- ary condition is numerically more effective. 展开更多
关键词 euler-Bernoulli beam. Artificial boundary con- dition - Wave propagation
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DIFFERENCE DISCRETE SYSTEM OF EULER-BEAM WITH ARBITRARY SUPPORTS AND SIGN-OSCILLATORY PROPERTY OF STIFFNESS MATRICES
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作者 王其申 王大钧 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第3期393-398,共6页
The difference discrete system of Euler-beam with arbitrary supports was constructed by using the two order central difference formulas. This system is equivalent to the spring-mass-rigidrod model. By using the theory... The difference discrete system of Euler-beam with arbitrary supports was constructed by using the two order central difference formulas. This system is equivalent to the spring-mass-rigidrod model. By using the theory of oscillatory matrix, the signoscillatory property of stiffness matrices of this system was proved, and the necessary and sufficient condition for the system to be positive was obtained completely. 展开更多
关键词 euler-beam difference discrete systems stiffness matrices sign-oscillatory property
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含多维随机变量的广义概率密度演化方程解析解:以Euler-Bernoulli梁为例
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作者 周永峰 李杰 《力学学报》 EI CAS CSCD 北大核心 2024年第9期2659-2668,共10页
广义概率密度演化方程的解析解,不仅具有重要理论价值,而且具有校验数值解、进而标定数值算法误差的作用.以Euler-Bernoulli简支梁为例,推导给出了梁受迫振动时跨中位移响应所对应的广义概率密度演化方程解析解.包括非平稳非高斯随机载... 广义概率密度演化方程的解析解,不仅具有重要理论价值,而且具有校验数值解、进而标定数值算法误差的作用.以Euler-Bernoulli简支梁为例,推导给出了梁受迫振动时跨中位移响应所对应的广义概率密度演化方程解析解.包括非平稳非高斯随机载荷作用下的解(包含2维随机变量)以及同时考虑载荷随机性和结构参数随机性时的解(分别包含2维、4维和5维随机变量).分析结果表明,真实的概率密度演化是一个十分复杂的过程,远不能用简单的概率分布函数加以描述.这一进展,可为概率密度演化理论的进一步深入研究提供一个方面的基础. 展开更多
关键词 广义概率密度演化方程 解析解 euler-Bernoulli 受迫振动 多维随机变量
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The Response of Viscously Damped Euler-Bernoulli Beam to Uniform Partially Distributed Moving Loads
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作者 Folake Oyedigba Akinpelu 《Applied Mathematics》 2012年第3期199-204,共6页
The paper investigates the response of non-initially stressed Euler-Bernoulli beam to uniform partially distributed moving loads. The governing partial differential equations were analyzed for both moving force and mo... The paper investigates the response of non-initially stressed Euler-Bernoulli beam to uniform partially distributed moving loads. The governing partial differential equations were analyzed for both moving force and moving mass problem in order to determine the behaviour of the system under consideration. The analytical method in terms of series solution and numerical method were used for the governing equation. The effect of various beam observed that the response amplitude due to the moving force is greater than that due to moving mass. It was also found that the response amplitude of the moving force problem with non-initial stress increase as mass of the mass of the load M increases. 展开更多
关键词 Viscously DAMPED euler-Bernoulli beam UNIFORM PARTIALLY DISTRIBUTED and MOVING Loads
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Recurrent formula of Bernoulli numbers and the relationships among the coefficients of beam,Bernoulli numbers and Euler numbers
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作者 老大中 赵珊珊 老天夫 《Journal of Beijing Institute of Technology》 EI CAS 2015年第3期298-304,共7页
Based on the differential equation of the deflection curve for the beam,the equation of the deflection curve for the simple beamis obtained by integral. The equation of the deflection curve for the simple beamcarrying... Based on the differential equation of the deflection curve for the beam,the equation of the deflection curve for the simple beamis obtained by integral. The equation of the deflection curve for the simple beamcarrying the linear load is generalized,and then it is expanded into the corresponding Fourier series.With the obtained summation results of the infinite series,it is found that they are related to Bernoulli num-bers and π. The recurrent formula of Bernoulli numbers is presented. The relationships among the coefficients of the beam,Bernoulli numbers and Euler numbers are found,and the relative mathematical formulas are presented. 展开更多
关键词 Bernoulli numbers euler numbers coefficients of beam simple beam equation of deflection curve Fourier series
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On the Buckling of Euler Graphene Beams Subject to Axial Compressive Load
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作者 Mohamed B. M. Elgindi Dongming Wei +1 位作者 Yeran Soukiassian Yu Liu 《World Journal of Engineering and Technology》 2014年第2期149-158,共10页
In this paper, we consider the buckling of an Euler-Bernoulli graphene beam due to an axial compressive load. We formulate the problem as a non-linear (eigenvalue) two-point boundary value problem, prove some properti... In this paper, we consider the buckling of an Euler-Bernoulli graphene beam due to an axial compressive load. We formulate the problem as a non-linear (eigenvalue) two-point boundary value problem, prove some properties of the eigenpairs and introduce a suitable numerical shooting method scheme for approximating them. We present the perturbation and the numerical approximations of the first and second buckling loads and the corresponding shapes. 展开更多
关键词 Critical BUCKLING Load Graphene euler-Bernoulli beam Non-Linear EIGENVALUE Problem SHOOTING Method
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EIGENFREQUENCIES OF THE THREE DIMENSIONAL EULER-BERNOULLI BEAM SYSTEM WITH DISSIPATIVE JOJNTS
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作者 William H. Paulsen(Department of Computer Science, Mathematics, and Physics, ArkansasState Unirersity, Arkansas. 72467, USA) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1995年第8期723-746,共16页
In this paper, we will compute the transfer matrices to find the eigenfrequenciesfor the vibrations of the general non-collinear Euler-Bernoulli or Timoshenko beamstructure with dissipative joints. We will allow the s... In this paper, we will compute the transfer matrices to find the eigenfrequenciesfor the vibrations of the general non-collinear Euler-Bernoulli or Timoshenko beamstructure with dissipative joints. We will allow the structure to be three dimensional,and thus we must consider all types of vibrations simulaneously, including longitudinaland torsional vibrations. The general structure considered will consist of any number ofbeams joined end to end to form a chain. Many, different kinds of dampers areallowed, even within the same structure. We also will allow different materials withinthe structure as well as different beam widths. We then will show. that asymptotic estimates can be used to find the eigenfrequencies approximately. 展开更多
关键词 ASYMPTOTICS coupled beams EIGENFREQUENCIES euler-Bernoulli Timoshenko linear joints
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Numerical Solution of Euler-Bernoulli Beam Equation by Using Barycentric Lagrange Interpolation Collocation Method
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作者 Haolu Zhang Lianwang Chen Lei Fu 《Journal of Applied Mathematics and Physics》 2021年第4期594-605,共12页
Euler-Bernoulli beam equation is very important that can be applied in the field of mechanics, science and technology. Some authors have put forward many different numerical methods, but the precision is not enough hi... Euler-Bernoulli beam equation is very important that can be applied in the field of mechanics, science and technology. Some authors have put forward many different numerical methods, but the precision is not enough high. In this paper, we will illustrate the high-precision numerical method to solve Euler-Bernoulli beam equation. Three numerical examples are studied to demonstrate the accuracy of the present method. Results obtained by our method indicate new algorithm has the following advantages: small computational work, fast convergence speed and high precision. 展开更多
关键词 Barycentric Interpolation Collocation Method euler-Bernoulli beam Equation Linearized Iterative
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Exact geometry based quasi-conforming analysis for Euler-Bernoulli beam
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作者 Ping Hu Yang Xia Changsheng Wang 《Theoretical & Applied Mechanics Letters》 2012年第5期6-9,共4页
The problem of quick analysis using exact geometry data was proposed by Hughes et al. and the isogeometric analysis framework was introduced as a solution. In this letter, the exact geometry concept is combined into t... The problem of quick analysis using exact geometry data was proposed by Hughes et al. and the isogeometric analysis framework was introduced as a solution. In this letter, the exact geometry concept is combined into the quasi-conforming framework and a novel method, i.e., the exact geometry based quasi-conforming analysis is proposed. In present method the geometry is exactly described by non-uniform rational B-spline bases, while the solution space by traditional polynomial bases. Present method combines the merits of both isogeometric analysis and quasi-conforming finite element method. In this letter Euler-Bernoulli beam problem is solved as an example and the results show that the present method is effective and promising. 展开更多
关键词 quasi-contbrming method isogeometric analysis non-uniform rational B-spline euler- Bernoulli beam exact geometry
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车辆-轨道系统振动响应分析——Timoshenko梁与Euler梁轨道模型的比较 被引量:15
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作者 徐志胜 翟婉明 +1 位作者 王开云 王其昌 《地震工程与工程振动》 CSCD 北大核心 2003年第6期74-79,共6页
近年来,铁路的高速化、高运量化以及轻微的地震灾害等因素加速了轨道结构的沉降或变形,导致车辆轨道系统振动的加剧。本文运用车辆-轨道耦合动力学理论,编制了基于Timoshenko梁钢轨模型的车辆-轨道耦合振动仿真分析软件,分析了车辆-轨... 近年来,铁路的高速化、高运量化以及轻微的地震灾害等因素加速了轨道结构的沉降或变形,导致车辆轨道系统振动的加剧。本文运用车辆-轨道耦合动力学理论,编制了基于Timoshenko梁钢轨模型的车辆-轨道耦合振动仿真分析软件,分析了车辆-轨道系统的垂向振动特性,并与基于Euler梁模型的VICT软件的仿真结果进行了比较分析。结果表明:仿真结果与VICT的仿真结果基本一致,但在较高频域,前者能更好地反映轮轨系统的高频特性。因而,在研究轮轨高频振动及轮轨噪声时,采用Timoshenko梁钢轨模型更具合理性。 展开更多
关键词 车辆-轨道耦合动力学 车辆振动 轨道振动 Timoehenko梁钢
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基于样条有限点法的变截面Euler梁横向自由振动分析 被引量:8
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作者 刘鹏 刘红军 +1 位作者 林坤 秦荣 《振动与冲击》 EI CSCD 北大核心 2016年第11期66-73,共8页
基于Bernoulli-Euler梁理论,采用样条有限点法建立考虑截面高宽度沿轴线性变化的变截面Euler梁振动分析的计算模型,通过沿梁轴线设置一定数量的样条节点对变截面梁样条离散化,采用三次B样条函数对梁的位移场进行插值,基于Hamilton原理... 基于Bernoulli-Euler梁理论,采用样条有限点法建立考虑截面高宽度沿轴线性变化的变截面Euler梁振动分析的计算模型,通过沿梁轴线设置一定数量的样条节点对变截面梁样条离散化,采用三次B样条函数对梁的位移场进行插值,基于Hamilton原理导出变截面Euler梁的振动方程,推导考虑截面尺寸变化效应的总刚度和总质量矩阵的表达式,并编制计算程序,算例分析表明,模型的变截面梁的横向自振频率解答与文献解答吻合良好,计算精度和计算效率高,且模型边界处理简单,取样条离散节点数为15时,模型可以取得较高精度且解答趋于稳定。模型可适用于不同边界、不同截面变化率和不同截面类型的变截面Euler梁的自由振动分析。 展开更多
关键词 欧拉梁理论 变截面梁 横向自由振动 样条有限点法
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Euler梁的无网格求解方法探讨 被引量:5
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作者 王东东 张灿辉 李庶林 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2006年第2期206-210,共5页
基于再生条件建立了一种用于Euler梁(薄梁)分析,同时考虑挠度和转角影响的双变量无网格计算方法.与现有采用固定基的双变量无网格近似相比,此方法采用移动基函数,有更小的数值再生误差;与只考虑挠度的单变量无网格近似相比,此方法有更... 基于再生条件建立了一种用于Euler梁(薄梁)分析,同时考虑挠度和转角影响的双变量无网格计算方法.与现有采用固定基的双变量无网格近似相比,此方法采用移动基函数,有更小的数值再生误差;与只考虑挠度的单变量无网格近似相比,此方法有更高的插值精度.这些特性在文中得到了数值验证.此外,通过推广位移边界条件处理的变换法,进一步把双变量无网格近似中广义节点挠度和转角系数与相对应的真实挠度和转角节点值联系起来,使得Galerkin无网格法求解Euler梁问题中挠度和转角边界条件的处理变得与有限元类似,较为便利.Euler梁算例表明,具有移动基的单变量与双变量两种无网格算法收敛速度相当,但采用移动基的双变量无网格法有更高的计算精度. 展开更多
关键词 euler 无网格法 固定基函数 移动基函数 再生条件
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变截面Euler-Bernoulli梁在轴力作用下固有振动的级数解 被引量:16
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作者 徐腾飞 向天宇 赵人达 《振动与冲击》 EI CSCD 北大核心 2007年第11期99-101,共3页
建立了截面特性、轴力和质量分布均连续变化的Euler-Bernoulli梁固有振动方程。采用Frobeniu方法求解方程,得到了方程的级数解析解;并计算了结构的振动频率与振型。算例证明了该方法的有效性,并表明轴向力的几何非线性效应对振动的低阶... 建立了截面特性、轴力和质量分布均连续变化的Euler-Bernoulli梁固有振动方程。采用Frobeniu方法求解方程,得到了方程的级数解析解;并计算了结构的振动频率与振型。算例证明了该方法的有效性,并表明轴向力的几何非线性效应对振动的低阶频率和自振振型有一定的影响,级数项数的取值对算法的收敛性有影响。 展开更多
关键词 euler-BERNOULLI梁 几何非线性 固有振动
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移动荷载作用下双层Euler梁模型土动力响应分析 被引量:3
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作者 谢伟平 王国波 于艳丽 《地震工程与工程振动》 CSCD 北大核心 2004年第1期82-86,共5页
本文以弹性波动理论为基础,利用分层法计算了双层连续支撑Euler梁下地基土的位移,同时考虑了不同的车辆荷载模型,并将计算的结果和单层Euler梁下地基土的位移进行了比较,比较表明:轨道结构本身和车辆悬挂体系具有一定的减振功能。因此,... 本文以弹性波动理论为基础,利用分层法计算了双层连续支撑Euler梁下地基土的位移,同时考虑了不同的车辆荷载模型,并将计算的结果和单层Euler梁下地基土的位移进行了比较,比较表明:轨道结构本身和车辆悬挂体系具有一定的减振功能。因此,该研究对由交通荷载引起的环境振动分析和评价具有一定的应用价值。 展开更多
关键词 弹性波动理论 分层法 地基土 弹性波 移动荷载 euler
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修正Timoshenko梁自由振动及Euler梁误差分析 被引量:5
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作者 徐梅玲 叶茂 +1 位作者 付明科 任珉 《科学技术与工程》 北大核心 2015年第15期88-94,共7页
基于考虑剪切变形所引起转动惯量的Timoshenko梁,采用分离变量法和高阶线性微分方程组特征值问题求解方法,系统地给出了修正Timoshenko简支梁模态特性的分析方法,推导得到了修正Timoshenko简支梁自振频率计算公式和振型函数表达式;并给... 基于考虑剪切变形所引起转动惯量的Timoshenko梁,采用分离变量法和高阶线性微分方程组特征值问题求解方法,系统地给出了修正Timoshenko简支梁模态特性的分析方法,推导得到了修正Timoshenko简支梁自振频率计算公式和振型函数表达式;并给出了Euler梁模型相对于修正Timoshenko梁模型的误差计算公式。分析结果表明:影响Euler梁模型计算误差的因素包括四个方面:振型阶数、材料泊松比、梁剪应力不均匀系数和回转半径与梁高跨比;随着振型阶数和高跨比的增加,Euler梁模型计算误差值迅速增长;在建筑材料泊松比的分布范围内,Euler梁模型计算误差随泊松比大约呈线性增长趋势;典型截面对Euler梁模型计算误差影响的排序为:圆形<矩形<T字型<圆管<箱型<工字型<H型,采用Euler模型计算工字型和H型截面梁振型频率时,需要特别加以注意。 展开更多
关键词 TIMOSHENKO梁 euler 简支梁 自由振动 误差
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插值矩阵法分析轴向受载的Euler-Bernoulli梁双向弯曲与扭转耦合振动 被引量:3
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作者 张金轮 葛仁余 +2 位作者 韩有民 牛忠荣 程长征 《合肥工业大学学报(自然科学版)》 CAS 北大核心 2017年第3期373-378,共6页
文章运用插值矩阵法研究了轴向受载的Euler-Bernoulli梁的双向弯曲扭转耦合自由振动问题。选择梁横截面的剪切中心作为坐标原点,坐标轴平行于梁截面的几何轴,振动微分方程中有关梁截面几何特性的参数均采用相对于几何轴的参数。轴向受载... 文章运用插值矩阵法研究了轴向受载的Euler-Bernoulli梁的双向弯曲扭转耦合自由振动问题。选择梁横截面的剪切中心作为坐标原点,坐标轴平行于梁截面的几何轴,振动微分方程中有关梁截面几何特性的参数均采用相对于几何轴的参数。轴向受载的Euler-Bernoulli梁的双向弯曲扭转耦合自由振动频率的计算转化为一组非线性常微分方程特征值问题,运用插值矩阵法求解,获得了3种边界条件下梁弯扭耦合振动的固有频率及其相应振型函数的计算结果,将数值计算结果与已有结果比较表明,文中方法具有很高的精度和效率。 展开更多
关键词 euler-BERNOULLI梁 轴向荷载 固有频率 插值矩阵法
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基于双层Euler-Bernoulli梁理论的浮置板轨道隔振研究 被引量:6
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作者 袁俊 吴敏哲 +1 位作者 孟昭博 宋林 《西安建筑科技大学学报(自然科学版)》 CSCD 北大核心 2009年第5期683-688,共6页
为减少城市交通系统运行所衍生的低频振动对人体和建筑物的影响,改善浮置板的动力特性,提高其对低频振动的隔振效果是目前亟待解决的问题.基于双层Euler-Bernoulli梁理论,给出了浮置板轨道结构在移动荷载作用下的耦合动力学分析模型.通... 为减少城市交通系统运行所衍生的低频振动对人体和建筑物的影响,改善浮置板的动力特性,提高其对低频振动的隔振效果是目前亟待解决的问题.基于双层Euler-Bernoulli梁理论,给出了浮置板轨道结构在移动荷载作用下的耦合动力学分析模型.通过双重Fourier变换将浮置板轨道系统在空间-时间域函数的微分方程转化波数-频率域函数的代数方程,求解频散曲线,分析荷载移动速度对频散特性的影响.然后使用围道积分法进行Fourier逆变换,将波数-频率域内动挠曲线位移解转换为空间-时间域内的解,求得浮置板轨道系统传递到基础的力,评价不同参数变化时浮置板的隔振范围和隔振性能.结果表明当荷载移动速度到达临界速度时,浮置板系统变形将趋向或处于失稳状态;在本文给出的浮置板单位长度质量、板下支承刚度和支承阻尼参数建议值范围内,对改善浮置板低频隔振性能效果显著. 展开更多
关键词 浮置板轨道 euler-BERNOULLI梁 低频振动 频散分析 隔振性能
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基于等效弹簧模型的裂纹Euler-Bernoulli梁弯曲变形分析 被引量:23
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作者 孙嘉琳 杨骁 《力学季刊》 CSCD 北大核心 2015年第4期703-712,共10页
考虑裂纹的缝隙效应,研究了开闭裂纹Euler-Bernoulli梁的弯曲变形.首先,将裂纹等效为内部旋转弹簧,利用广义函数,给出了考虑裂纹缝隙影响的Euler-Bernoulli梁的等效抗弯刚度,推导了具有任意数目开闭裂纹梁弯曲变形的显式通解.在此基础上... 考虑裂纹的缝隙效应,研究了开闭裂纹Euler-Bernoulli梁的弯曲变形.首先,将裂纹等效为内部旋转弹簧,利用广义函数,给出了考虑裂纹缝隙影响的Euler-Bernoulli梁的等效抗弯刚度,推导了具有任意数目开闭裂纹梁弯曲变形的显式通解.在此基础上,研究了均布载荷作用下上侧单裂纹简支梁以及裂纹处承受集中力和集中力偶共同作用的固支梁的弯曲变形,分析了梁长细比、裂纹深度和位置以及载荷等对裂纹开闭状态和梁弯曲变形的影响。结果表明:梁挠度分布在裂纹处存在尖点,而转角分布存在跳跃;梁挠度与载荷的响应关系一般为双折线形式,分别对应于裂纹的张开和闭合状态;且裂纹张开时,裂纹梁的柔度随着梁长细比的增加和裂纹深度的减小而减小。这些结果对梁裂纹无损检测具有指导意义. 展开更多
关键词 euler-BERNOULLI梁 开闭型裂纹 裂纹缝隙 广义函数 参数分析
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