MOHAMMED ABU-HILAL ,NABIL BEITHOU

2007 Journal of Mechanical Engineering 58,30-50

In this paper, the free vibration of an undamped triple-beam system on

elastic foundation is analysed. The system consists of three Euler-Bernoulli

beams of the same length that are arranged in parallel and continuously connected

by elastic layers. The natural frequencies and the mode shapes of the

system are determined. Furthermore, the initial value problem is solved to find

the time-dependent free vibrations of the beams. Using a numerical example,

the effects of the layer stiffnesses and those of the masses of the beams per

unit length on the natural frequencies and the mode shapes are investigated in

detail.