Free vibration of an axially preloaded laminated composite beam carrying a spring-mass-damper system with a non-ideal support

Majid Ghadiri^*, Keramat Malekzadeh, Faramarz Ashenai Ghasemi

Jordan Journal of Mechanical and Industrial Engineering, Volume 9, Issue 3, 2015(6), Pages 195-207. (ISI)

Abstract
This paper investigates the effect of a non-ideal support on free vibration of an Euler-Bernoulli composite beam carrying a mass-spring-damper system under an axial force. The beam simply supported boundary conditions and it is assumed that one of its supports is non-ideal. Therefore, it has a small non-zero deflection and a small non-zero moment. The governing equations of the problem constitute a coupled system including a PDE and an ODE. To solve the problem, the Galerkin method is employed in the displacement field in conjunction with the average acceleration method in the time domain. The effect of a non-ideal support of composite beam, under axial force on natural frequencies and mode shapes of the system, is studied in details. For the validation of the performed solution and the obtained results, in a special case, the fundamental frequency was compared with those cited in the literature. The obtained results show that with increasing the perturbation parameter, the fundamental frequency decreases. This behavior is independent of the fiber directions of the beam. Also, the beams having fully-ideal supports will be buckled sooner than the beams with semi-ideal supports.

Keywords

Beam; Free vibration; Axial load; Non-ideal support; Spring-mass-damper system.