A review of the characteristics and structural behaviour of sandwich panels

With advances in materials science and engineering, sandwich panels have evolved over the years. They are now used extensively in many fields, including the construction industry, due to their light weight and ease of construction. In the past, metals and timber-based products constituted most of the facing materials of panels, but plastics, polymers, concrete and other cementitious facings reinforced with glass, steel, carbon, natural fibres or textiles are now finding increasing use as facing materials. Core materials have also evolved and now include balsa and other types of wood, expanded polystyrene, rigid foams and foamed or lightweight cements and concretes. Some of today's novel cores incorporate various lattice-, truss- or pyramid-type structures while others have honeycombs. This study reviews structural sandwich panels with non-profiled faces and a range of innovative core composites and configurations. Particular focus is given to the properties that make panels suitable as structural systems, as well as any inherent weaknesses or peculiarities that require due consideration in design, including their structural response to bending and compression and associated failure modes. Finally, a brief review of theoretical developments is provided, along with representative problems using the theoretical models.