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In this work, a fifth-order shear deformation theory is computed using the layer-wise model to determine non-dimensional fundamental frequencies. The theoretical, experimental, and finite element analysis (FEA) results are compared for a standard isotropic material. Hand layup technique is used to prepare glass fiber reinforced polymer composites (GFRPC) with selective layers filled with graphene and flyash. This technique helps to reduce the fabrication cost as the whole structure is not to be strengthened by the fillers. Six classes of the laminated-composite-plate (LCP) such as outer layer graphenated LCP (O-LCP), core layer graphenated LCP(C-LCP), functionally graded LCP (FG-LCP), LCPs only rich in graphene (G-LCP), LCPs only rich in flyash (F-LCP) along with a neat epoxy-glass LCP (N-LCP) are fabricated. A low-cost frequency measurement module is set-up to measure the fundamental frequency (FF) of the fabricated LCPs. FFs, amplitudes, non-dimensional stress parameters, and central deflection of the LCPs under harmonic load, the buckling strength, and displacements of the LCPs are calculated. It is found that harmonically excited C-LCP and O-LCP have better stability accompanied by lower deflections, followed by G-LCP as compared to other kinds of LCPs. Also, the addition of graphene increases the buckling strength of LCPs, which portrays that the local layer filling is a useful technique to enhance the strength of the LCPs.

The strength of the conventional composite plates can be enhanced by the use of additional fillers. These composite plates are often subjected to dynamic loading conditions which necessitate the study of their static and dynamic behavior. In this study, laminated composite plates (LCP) are fabricated by open layup process with epoxy as a base resin, E-glass fiber as reinforcement, and fillers: flyash and graphene. The fillers are included in order to improve the mechanical properties of the composite. The filler content in the composite is limited to 5% of the total volume. The weight percentage of fiber combined with fillers, treated as reinforcing constituents is limited to 60%. Graphene and flyash are added in different proportions to develop different kinds of LCPs. The free and forced vibrations of LCPs (using simple support end conditions) are measured by an indigenously developed low-cost vibration testing module. The experimental results have been used to validate the results obtained from the mathematical modeling by using fifth-order shear deformation theory and finite element approaches. Additionally, the effect of existing discontinuity in the LCP is studied. Circular holes of different dimensions at different locations are simulated in the numerical model and the consequences on modal frequencies are analyzed.

The uses of laminated composite beams are increasing day by day in many industries. This laminated composite beam has been exposed under different dynamic loadings in mechanical operation. Therefore, the dynamic investigation of laminated composite beams (LCB) is very much necessary to forecast the catastrophe fail of the LCB components. At present, dynamic investigation of the LCB is carried out by the determining of fundamental frequency and mode shape. The special attentions like; in the design of geometry, orientation of fibres, layup of sections and boundary conditions are also analysed with referring the dynamical loadings and industry uses. The analysis procedures and results are validated with the reference results using finite element analysis software. Present research deals with the consequence of different volume fraction, boundary conditions and geometrical variation like aspect ratio, geometric ratio and length of E-glass polyester LCB. By altering different stacking sequences and these effects on mechanical properties as well as natural frequency are also analysed.