Abstract
This paper proposes a method for predicting modal damping ratios of a structure which consists of resin-based composite material with complex local structure using finite element analysis. If these modal damping ratios are given, a vibration analysis considering the frequency dependent structural damping can be achieved. However, it is difficult to estimate exactly the modal damping ratios by theoretical means. Therefore we proposed a method of identifying the damping ratios using numerical analysis based on the mathematical homogenization method. The natural frequencies and the mode shapes calculated by present analysis method were in good agreement with the results of the vibration measurement of particle-dispersed composite material plate. The calculated modal damping ratios, in terms of mode shape dependence and Vf dependence, had a good representation of the qualitative features of the experimental results. The magnitude of the calculated modal damping ratios, however, tend to be slightly greater than the experimental values.
