Elastoplastic analysis of honeycombs with consideration for geometric nonlinearity

Abstract

<p indent=0mm>The elastoplastic model of hexagonal honeycombs having a constant wall thickness with consideration for geometric nonlinearity is established herein based on the nonlinear beam and elastoplastic theories. The solution algorithm is researched to obtain the stress-strain relationship and Poisson’s ratio of the honeycombs. A finite element model of the honeycombs is established to verify the proposed method. The stress-strain relationships and Poisson’s ratio of the honeycombs with different parameters (including different ratios of the thickness of honeycomb wall to the length of the inclined wall <italic>t</italic>/<italic>l</italic>, different ratios of the height of the vertical wall to the length of the inclined wall <italic>h</italic>/<italic>l</italic>, and different inclination angle <italic>θ</italic>) are obtained. Furthermore, the influence of the geometric and material nonlinearities on the stress-strain relationship of the honeycombs is analyzed. The geometric nonlinearity increases the overall stiffness of honeycombs with the increase in strain. Then, it decreases gradually owing to the plastic deformation.