Harmonic response analysis of symmetric laminated composite beams with different boundary conditions

This study deals with the determination of the harmonic response of symmetric laminated composite beams by the finite element method. The structural stiffness of the composite beam is determined by the classical laminated plate theory. Four different ply orientations, namely, [0](2s), [0/90](s), [45/-45](s), and [90](2s) are used to examine the effect of the stacking sequence on the harmonic response of the beam. Proportional damping is used to model the structural damping, and the damped harmonic responses of the composite beams are obtained to show the effect of the damping on the harmonic response. The effect of the boundary conditions on the harmonic response is also investigated. The displacement maps calculated for varying excitation points are obtained for different boundary conditions and damping ratios at different vibrational modes. The numerical results presented in this study show that the magnitudes of the harmonic response of the composite beam increase as the flexural rigidity decreases, and the vibration magnitudes reduce considerably with damping. The vibration patterns created for varying excitation and observation locations change as the damping ratio and excitation frequency change.