Experimental and numerical study on free vibration characteristics of laminated composite plate with/without cut-out

The experimental and numerical study related to the free vibration characteristics of laminated composite plates with/without cut-out is presented in this paper. The natural frequencies are obtained from the experimental analysis using FFT analyzer. Similarly, these frequencies are also obtained from the finite element analysis employing nine-nodded isoparametric plate element. The effects of aspect ratio (0.5, 1.0. 1.5 and 2.0), number of layers (8, 12 and 16), different weight fraction of fibre and epoxy (70:30, 50:50 and 40:60) and different orientations of fibres, i.e. (0/90)(2s), (45/-45)(2s) and (30/-30)(2s), on the natural frequencies of the laminated composite plates are studied for various boundary conditions. The different parameters considered for the free vibration analysis of plate with cut-out are the size of cut-out, location of cut-out, i.e. concentric/eccentric cut-out, and thickness and the ply orientation of the laminated plate. It is observed that the natural frequencies obtained from both the experimental and finite element methods for these cases are in good agreement. Moreover, the above parameters greatly influence the natural frequencies of the laminated composite plate with/without cut-out. Further, this study will help in providing adequate knowledge and confidence to the designer for the design of laminated composite plates with sufficient accuracy.