On the strain gradient effects on buckling of the partially covere d laminate d microb eam

The buckling responses of the micro-components show size dependency. The general strain gradient theory is applied to explain the size effects. In this paper, we derive the theoretical relations among the classical couple stress theory, the modified couple stress theory and the general theory. The general theory includes all strain gradients and can respectively reduce to the classical couple stress theory and the modified couple stress theory when certain strain gradients are ignored. Subsequently, we further compare the difference of the ability of the general theory and the reduced theories to capture the size dependent buckling response of the beam. The buckling load of the beam predicted by the general theory is larger than that predicted by the reduced theories. The general theory can predict the size dependency more accurately. In addition, the variation law of buckling load with the location of the upper elastic layer is also clarified. The location variation of the upper elastic layer leads to the change of buckling load, and thus affects the ability of the beam to resist the deformation. (c) 2021 Elsevier Inc. All rights reserved.

Automated summary

This study investigates the size-dependent buckling response of micro-components and the relationship among couple stress theories, modified couple stress theory, and general strain gradient theory. The results show that the general theory can predict the size dependency more accurately and capture more details of the buckling response compared to the reduced theories.