BUCKLING AND NONLINEAR RESPONSE OF SANDWICH PANELS WITH TEMPERATURE DEPENDENT CORE PROPERTIES

摘要

The paper deals with the buckling response and non-linear behaviour of sandwich panels with "soft" cores with temperature-dependent mechanical properties subjected to thermally induced deformations and mechanical loads. The study investigates the effects of the degradation of mechanical properties as a result of rising temperature. The formulation is based on the high-order sandwich panel (HSAPT) approach, which takes into account the flexibility of the core in the vertical direction, as well as the dependency of the mechanical core properties of the temperature distribution through the core depth. The stress and deformation fields of the core have been derived analytically. The buckling equations are derived using the perturbation technique, and the critical temperatures and modes of local and global buckling are determined through the solution of nonlinear algebraic equations. Numerical results obtained for different temperature distributions, different boundary conditions and the simultaneous action of thermal and mechanical loads are presented. It is shown that an unstable non-linear response occurs when external mechanical and thermal loads act simultaneously on an unrestrained sandwich panel.