A modified fifth-order shear deformation theory for analyzing laminated composite plates with filler materials

Development of new theories are essential for the analysis of laminated-composite-plates (LCPs) with modifications in reinforcements, matrix, aspect-ratios, and boundary-conditions. Here, a higher order shear-deformation-theory of fifth-order (MFSDT) is proposed for the static and modal analysis of LCPs modified with filler material (flyash/graphene; weight % range: 0% to 10%). The proposed MFSDT is compared to other plate-theories of past literature, and it reflects the robustness with a minimum error of 2.6%. Further, using this theory, the effect of filler on the modal response of LCPs (two different combinations (i) epoxy+ E-glass + flyash, and (ii) epoxy+ E-glass + graphene) are studied. The results are compared with results of experimental and finite element analysis. Further, using the proposed MFSDT, the static analysis of the LCPs are conducted to examine stress components, centre-deflection considering aspect ratio, load variation at the centre of the LCP, and filler percentage. Also, the effect of stacking sequences on the developed stress components, centre-deflection, and fundamental frequencies of LCPs are evaluated. It is observed that off-plane stresses are least affected by addition of filler content whereas fundamental frequencies, normal stresses, and centre deflection are significantly changed.