Large Deformation Effect on Dynamic Deflection Responses of Cutout-Borne Composite Shell Panel: An Experimental Validation

Abstract

The nonlinear dynamic deflection and stress responses of a multilayered shallow shell structure with cutout subjected mechanical pulse load were investigated. The theoretical model was developed using equivalent single-layer theory in the context of third-order midplane displacement polynomials. The geometrical nonlinearity was introduced using Green-Lagrange (retaining higher-order small strain terms) and von-Karman strain (neglecting the small-strain terms of higher order) to account for large-amplitude oscillation of the shell structure. Hamilton’s variational principle was used to derive the equation of motion. The nonlinear solution was calculated using the direct iterative method. Following the derived mathematical expressions, a computational program was prepared using the isoparametric finite-element (FE) approach in the MATLAB version 2018a platform. The computational model cogency has been confirmed by relating the results to previously published results. Besides, experimentally obtained dynamic deflection values were compared with computational results. The results highlight the importance of the nonlinear terms in the Green-Lagrange strain, which are neglected under the von-Karman assumptions. The critical dynamic behavior of the laminated shallow shell structure with the cutout of variable shapes and sizes was examined by varying geometrical, boundary support, and loading conditions.