Exact mathematical solution for nonlinear free transverse vibrations of beams

被引:0
作者
Asadi-Dalir M. [1 ]
机构
[1] Department of Mechanical Engineering, Bu-Ali Sina University, Hamedan
关键词
Beam; Deformed coordinates; Exact mathematical solution; Geometrically nonlinear terms; Mode shape;
D O I
10.24200/SCI.2019.50562.1764
中图分类号
学科分类号
摘要
In the present paper, an exact mathematical solution is obtained for the nonlinear free transverse vibration of beams for the rst time. The governing nonlinear partial di erential equation in un-deformed coordinates system is converted in two coupled partial di erential equations in deformed coordinates system. Then, a mathematical explanation is obtained for the nonlinear mode shapes as well as natural frequencies versus geometrical and material properties of the beam. It is shown that as the sth mode of transverse vibration is excited, the 2sth mode of the in-plane vibration will be developed. The results of the present work is compared with those obtained by the Galerkin method and the observed agreement will con rm the exact mathematical solution. It is shown that the governing equation is linear in the time domain. As a parameter, amplitude to length ratio (=l) is proposed to show when the nonlinear terms become dominant in the behavior of structure. © 2020 Sharif University of Technology. All rights reserved.
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页码:1290 / 1301
页数:11
相关论文
共 45 条
[1]  
Bernoulli J., Essai theorique sur les vibrations de plaques elastiques rectangulaires et Libres, Nova Acta Acad. Petropolit, 5, pp. 197-219, (1789)
[2]  
Timoshenko S.P., On the correction for the shear of the di erential equation for transverse vibration of prismatic bars, Phil. Mag, 41, pp. 744-746, (1921)
[3]  
Timoshenko S.P., On the transverse vibration of bars of uniform cross sections, Phil. Mag, 43, 6, pp. 125-131, (1922)
[4]  
Reddy J.N., A simple higher order theory for laminated composite plates, J. App. Mech, 51, pp. 745-752, (1984)
[5]  
Pai P.F., Nayfeh A.H., Nonlinear nonplanar oscillations of cantilever beam under lateral base excitation, Int. J. Non. Linear. Mech, 25, pp. 455-474, (1990)
[6]  
Pai P.F., Nayfeh A.H., A nonlinear composite beam theory, Nonlinear. Dyn, 3, pp. 431-463, (1992)
[7]  
Pai P.F., Palazotto A.N., Greer J.M., Polar decomposition and appropriate strain and stresses for nonlinear structural analysis, Comp. Struct, 66, pp. 823-840, (1998)
[8]  
Hodges D.H., Dowell E.H., Nonlinear equation of motion for the elastic bending and torsion of twisted non-uniform rotor blades, (1974)
[9]  
Hodges D.H., NASA TM X-73, (1976)
[10]  
Dowel E.H., Traybar J., Hodges D.H., An experimental-theoretical correlation study of nonlinear bending and torsion deformations of a cantilever beam, J. Sound. Vib, 50, pp. 533-544, (1977)