BUCKLING OF UNBALANCED, SANDWICH PANELS WITH TITANIUM AND GRP SKINS

An unbalanced and asymmetric sandwich composite structure consisting o f Titanium 6-4 and glass-reinforced plastic (GRP) skins with a phenoli c honeycomb core is being considered for construction of a surface shi p mast which will enclose critical shipboard equipment. Stability of t he structure is one of the major concerns in the design process. This research focuses on analytical and experimental studies of an unbalanc ed composite sandwich beam subjected to a compressive axial load. The failure load (i.e., peak load) and failure mode of each skin material and tile sandwich construction were measured at the laboratory. An ana lytical model was developed for predicting the failure load of the unb alanced and asymmetric sandwich composite configuration, including the transverse shear energy of the core material. The experimental data a greed wry well with analytical prediction. Postbuckling failure, as we ll as residual strength after initial failure, were also studied.