The role of nonlinear torsional contributions on the stability of flexural-torsional oscillations of open-cross section beams

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• 作者：Angelo Di Egidio^a ; ^{angelo.diegidio@univaq.it" class="auth_mail" title="E-mail the corresponding author} ; Alessandro Contento^b ; ^{content2@illinois.edu" class="auth_mail" title="E-mail the corresponding author} ; Fabrizio Vestroni^c ; ^{vestroni@uniroma1.it" class="auth_mail" title="E-mail the corresponding author}
• 刊名：Journal of Sound and Vibration
• 出版年：2015
• 出版时间：8 December 2015
• 年：2015
• 卷：358
• 期：Complete
• 页码：236-250
• 全文大小：970 K

文摘

An open-cross section thin-walled beam model, already developed by the authors, has been conveniently simplified while maintaining the capacity of accounting for the significant nonlinear warping effects. For a technical range of geometrical and mechanical characteristics of the beam, the response is characterized by the torsional curvature prevailing over the flexural ones. A Galerkin discretization is performed by using a suitable expansion of displacements based on shape functions. The attention is focused on the dynamic response of the beam to a harmonic force, applied at the free end of the cantilever beam. The excitation is directed along the symmetry axis of the beam section. The stability of the one-component oscillations has been investigated using the analytical model, showing the importance of the internal resonances due to the nonlinear warping coupling terms. Comparison with the results provided by a computational finite element model has been performed. The good agreement among the results of the analytical and the computational models confirms the effectiveness of the simplified model of a nonlinear open-cross section thin-walled beam and overall the important role of the warping and of the torsional elongation in the study of the one-component dynamic oscillations and their stability.