EIGEN ANALYSIS OF FIBER-REINFORCED COMPOSITE PLATES

Composites plates of various orientation and thickness with fiber-rein forced plastics (FRP) find increasing applications in aerospace and au tomotive structures (due to their high strength, stiffness to weight r atios, and high damping characteristics). Determination of the dynamic characteristics and the investigation of such structures are essentia l not only in the design but also in manufacture development. In the p resent paper, the eigen analysis of laminated square plates with vario us fiber orientations, various boundary fixations, and different stack ing sequences has been presented and discussed. The experimental analy sis and finite element techniques are utilized to study the effect of fiber orientation and boundary conditions on the dynamic characteristi cs of frequency and mode shapes. The vibrational system technique is u tilized for experimental measurements. The results show agreement betw een experimental and theoretical investigations. Also, these results s how a close connection between damping and stiffness characteristics i n glass-fiber composites.