Vibrations of beams and rods carrying a moving mass

5th Symposium on the Mechanics of Slender Structures

物理学;力学

Zhao, X.W.^1,2 ; Van Der Heijden, G.H.M.^1 ; Hu, Z.D.^2

Department of Civil, Environmental and Geomatic Engineering, University College London, London, United Kingdom^1

School of Aerospace Engineering and Applied Mechanics, Tongji University, Shanghai, China^2

关键词: Cosserat rod theories;    Deformation structure;    Elastic structures;    Euler-Bernoulli;    Launch system;    Resonance detuning;    Shallow arch;    Small deflection;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/721/1/012016/pdf
DOI  :  10.1088/1742-6596/721/1/012016

学科分类：力学，机械学

来源: IOP

【 摘 要 】

We study the vibration of slender one-dimensional elastic structures (beams, cables, wires, rods) under the effect of a moving mass or load. We first consider the classical small- deflection (Euler-Bernoulli) beam case, where we look at tip vibrations of a cantilever as a model for a barreled launch system. Then we develop a theory for large deformations based on Cosserat rod theory. We illustrate the effect of moving loads on large-deformation structures with a few cable and arch problems. Large deformations are found to have a resonance detuning effect on the cable. For the arch we find different failure modes depending on its depth: a shallow arch fails by in-plane collapse, while a deep arch fails by sideways flopping. In both cases the speed of the traversing load is found to have a stabilising effect on the structure, with failure suppressed entirely at sufficiently high speed.