Two benchmarks to assess two-dimensional theories of Sandwich Composite Plates

Two-dimensional theories and e nite elements are assessed to analyze displacement and stress e elds in sandwich, composites plates. Two benchmarks are used to conduct the assessment. The e rst benchmark is a sandwich plate loaded by harmonic distribution of transverse pressure for which a three-dimensional closed-form solution exists in the literature. The second benchmark is a rectangular sandwich plate loaded by a transverse pressure located at the center. More than 20 plate theories and e nite elements were implemented in a unie ed formulation recently proposed by the authors. Classical theories based on displacement assumptions are compared to advanced mixed modelsformulatedonthebasisofReissner’ smixedvariationaltheorem.Bothequivalentsingle-layermodelsaswell as layerwise models are considered. Analytical closed-form solutions and e nite elements are given. The considered benchmarks highlight both the performance and limitations of the considered two-dimensional theories. The convenience of layerwisedescription and advanced mixed theorieshas been demonstrated. Thesecond benchmark especially proved the need for layerwise models to capture the local effects.