Microstructural-dependent nonlinear stability analysis of random checkerboard reinforced composite micropanels via moving Kriging meshfree approach

Abstract

In the present study, through matching the moving Kriging meshfree formulations with the third-order shear flexible shell model together with the modified strain gradient continuum mechanics, the microstructural-dependent nonlinear stability behavior of micropanels under axial compression is explored. The micropanels are made of composites containing graphene nanoplatelets dispersed in random checkerboard pattern. The associated material characteristics are evaluated via a probabilistic-based homogenization scheme. Afterward, proper meshfree functions are implemented to enforce the essential boundary conditions at the considered nodding system accurately. It is highlighted that the stiffening characters of the microstructural gradient tensors cause to rise the critical stability load as well as the critical shortening of composite micropanels. Also, these stiffening characters make an enhancement in the minimum snap-through postbuckling compression, and shift it to lower values of the panel deflection and end shortening. Additionally, it is demonstrated that among different microstructural gradient tensors, the stiffening character of rotation gradient is more than deviatoric stretch gradient, the stiffening character of the later is more significant than the dilatation gradient tensor.