Paper number 439

DYNAMICAL CHARACTERISTICS OF FIBRE COMPOSITES

Werner Hnfenbach Carsten Holste Günther Pfeifer

Institut fur Leichtbau und Kunststofftechnik lnstitut für Technische Akustik
Technische Universität Dresden D 01062 Dresden Germany

Summary

Advanced lightweight applications for dynamically loaded structures increasingly have to satisfy extreme requirements concerning their dynamic behaviour. This leads to a rising need to use load-adaptedly designed material characteristics. Only in this way a structural dynamic design following the function integrating modern lightweight principals is possible. With the carbon fibre reinforced polymers (CFRP) coming up lately damping properties can he realized which are markedly superiour to those of light metals. Besides the existing dependence of stiffness and strength on the fibre orientationfthe material damping shows a pronounced anisotropyf as well. Therefore this anisotropic damping has to he considered as an optimization variable of the structural-dynamic design. In this paper the structural vibration of lightweight structures is presented which is a complex function of material damping value eigenmodes frequency and boundary conditions. Therefore the investigations were carried out using advanced experimental techniques and numerical simulation methods such as the Laser Scanning Vibration Interferometer (LASVI) and the Finite Element (FEM). As a practical example the structural dynamic design of a CFRP plate with restricted eigenfrequencies and critical buckling loads is presented.

Keywords

anisotropic damping, structural dynamic design, analytical and numerical simulation.