A high-order model for free vibrations of singly curved sandwich beams is presented. The model takes into account the transverse flexibility of the sandwich core while the faces of the sandwich are treated as thin beams. Linear equations of motion as well as the natural boundary conditions are derived. Verification of the model is performed for straight beams via a number of asymptotic cases. For the straight and curved sandwich beams, it is shown that there exist four eigenmodes. Their nature is clarified, and simple theoretical estimations for the eigenfrequencies are obtained. A numerical analysis of free vibration of the simply supported beams is carried out. Effects of design parameters of the sandwich constituents on the eigenmodes and their appropriate frequencies are investigated. The developed model may find its use in the context of various applications of curved sandwich members in the high-performance vehicles.
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