Nonlinear Finite Element Analysis of Thin-Walled Beam on Pre- and Post-Buckling Stiffness and Gauge Sensitivity Index

Abstract

Lightweight design has a significant impact on reducing fuel consumption and harmful emission of conventional vehicles and improving driving range of electric vehicles. Reducing the thickness of components in vehicle bodies and closures is an efficient approach for weight reduction. Thickness reduction, however, will reduce structural stiffness, especially in the presence of lateral displacements of buckling when critical stress is reached. In this paper, nonlinear FEA models of a thin-walled beam with variable thickness are developed for calculating the changes of beam stiffness as to thickness reduction in the pre- and post-buckling stages. Next, these stiffness values are used to calculate gauge sensitivity of the beam, which changes with respect to beam thickness changes. It is concluded that the presence of buckling will reduce the beam stiffness, worsen the stress uniformity, and increase the gauge sensitivity value of the beam.