Estimation of compressive response of egg-box panel and its designing to reduce the load fluctuation

Abstract

In this paper, the compressive response of an egg-box panel was investigated using a nonlinear FE analysis. The egg-box panel was based on spherical shells and frusta, and its compressive response was predicted by considering the theoretical compressive responses of the spherical shell and frusta individually. Given that the material’s strain-hardening characteristics enhance the compressive response of the egg-box panel, the compressive response would be underestimated by using the initial yield stress as a material parameter. Instead, the flow stress based on the initial yield stress, the strain-hardening exponent in the nonlinear stress-strain curve and the ultimate tensile strength were effective for estimating the compressive response of egg-box panel. Also, the compressive load continued to increase as the displacement increased. By adopting appropriate dimensions for the flat-shaped basement in the egg-box panel, a uniform load-displacement curve could be obtained.