1.School of Civil Engineering and Transportation,South China University of Technology, Guangzhou 510640,China;
2.China-Singapore International Joint Research Institute, Guangzhou 510700,China
Abstract:Structural vibration frequency is an important index of its dynamic characteristics and an important parameter of structural dynamic analysis and control. The potential energy functional equation of the basic structure is established by using a set of eigenfunctions and the corresponding eigenvalues. By using the Lagrange multiplier method and considering the additional constraint conditions in the functional, the frequency equation of the transverse vibration of a multi-point constrained bar under axial force is derived. At the same time, an analytical solutions of the vibration frequency and Euler critical force are obtained. Through the finite element simulation, the accuracy and effectiveness of the formula are verified in the case of simple support and fixed support. This method is suitable for fast estimation of vibration frequency and Euler critical force of complex constraint bar under axial force, and optimization of constraint locations and quantities.
Key words: vibration frequency; multi-point constraints; Euler critical force; finite element simulation
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