Postbuckling of thin wood-based sandwich panels due to hygroexpansion under high humidity

This study was carried out to investigate the postbuckling behavior of thin wood-based sandwich panels under high humidity. Using the Rayleigh-Ritz me thod based on the von Karman nonlinear theory for the panel, the solutions for both the approximate and the closed form for postbuckling of orthotropi c panels were derived to evaluate the deflection for the boundary condition of all clamped edges. The results suggested that the edge movement be cons idered for evaluation of a critical moisture content and deflection of thin wood-based panels fixed on the core with an adhesive. The numerical soluti on obtained from the derived model showed some discrepancy with the experim ental results. The predicted results overestimated the center deflection of the panels because creep and plastic deformation might be caused by consid erable in-plane stress on panels.