Inplane compressive response and failure of circular cell honeycomb.

Abstract

The behavior of a polycarbonate circular cell honeycomb material under four types of loading conditions is studied through a combination of experiment and numerical simulation. First, the crushing responses of the honeycomb material to two different uniaxial static loading conditions under displacement control are analyzed. In the first phase of the response, the material deforms in a uniform fashion. Next, the nonlinear phase caused by the progressive localization of deformation is characterized by the variation of stiffness. The progressive localization causes the walls of each cell to contact. Second, the crushing responses of the honeycomb material to three different uniaxial dynamic loading conditions are analyzed. The unaxial dynamic experiments are carried out using a low velocity impact drop tower. Third, the crushing responses of the honeycomb material to several inplane biaxial static loading histories under displacement control are analyzed. Experimental measurements indicate how the stress-strain response changes as a function of load biaxiality. Finally, the crushing responses of the honeycomb material to various inplane biaxial dynamic loading histories are analyzed. All of these experimental results are understood through simulation using the finite element method. In addition, the inplane properties of the honeycomb material are analytically studied and the sensitivities of the inplane properties of the honeycomb material to two types of imperfections (wall thickness and wall thickness variation of the honeycomb cell and the deviation from circularity for each cell of the honeycomb material) are investigated through an analytical method.