The finite element technique for predicting the natural frequencies,mode shapes and damping values of filamentary composite plates

This article presents the numerical method for predicting the natural frequencies, mode shapes and damping values of filamentary composite plates. This method is based on finite element technique, using damped element and allowing transverse shear deformation. For the example of this technique, the theoretical results comparing with experimental values of carbon fibre and glass fibre reinforced plastics plates (mid-plane symmetric) are provided. The dynamic properties of these laminates are discussed. Finally, a simple graphic technique to estimate the natural frequencies and damping values is suggested.