Damped Response of Symmetric Laminated Composite Beams to Moving Load with Different Boundary Conditions

The aim of this study is to present the damped dynamic response of a symmetric laminated composite beam with different boundary conditions. A three-dimensional finite element model based on the classical laminated plate theory is used together with the Newmark integration method in order to obtain the dynamic response of the beam. A computer code written in MATLAB (R) was developed in order to perform the dynamic analyses. The proportional damping which is referred to as Rayleigh damping is employed in the dynamic analyses. The impulse, step and moving load responses of the composite beam are presented for different damping ratios. The effect of the damping ratio on the dynamic magnification value, which is defined as the ratio between the dynamic and static displacements calculated for the mid point of the beam, is investigated. The normalized time values at which the maximum mid-point displacements occur are presented. The results reported in this article show that the largest dynamic magnification values are recorded for a pinned-pinned beam and the dynamic magnification values decrease as the damping ratio increases.