Vibration and damping analysis of thin-walled box beams

Thin walled box sections are used as load bearing members in various industries, aircraft structures and marine vessels. To avoid undesirable effects of the surrounding vibration environment, the structure can be designed to have natural frequency removed from the range of exciting frequency or by introducing damping. In the present study the vibration and damping behaviour of layered composite box beams is analysed using the finite element method. The finite element formulation is based on first order shear deformation theory, which takes shear deformation of the beam into consideration. The effect of the number of layers, end conditions and fiber angle on frequency and loss factor is studied for two materials, namely, graphite-epoxy and glass-epoxy. © 1998 Academic Press.