A novel unified multi-field vibration analysis of curved nanocomposite sandwich beams

This study investigates the influence of graphene origami (GOri) reinforcement and multi-field piezoelectric/piezomagnetic loading on the natural frequency characteristics of a sandwich curved beam. The structure consists of a GOri-reinforced composite core integrated with piezoelectric and piezomagnetic layers. A higher-order shear deformable model incorporating thickness stretch effects is developed to establish the kinematic relationships. The constitutive equations are derived by combining: Micromechanical models for the effective material properties of the GOri-reinforced core, Multi-field coupling equations for the piezoelectric/piezomagnetic layers. The governing equations of motion are obtained using Hamilton's principle and solved analytically. The natural frequency responses are systematically analyzed with respect to: GOri foldability parameters and reinforcement content, Multi-field (electro-magneto-elastic) loading conditions, Geometric parameters of the curved beam, Elastic foundation characteristics. The model is validated through comparison with existing literature before presenting new results. This work provides fundamental insights into the dynamic behavior of smart sandwich structures with tunable graphene-based reinforcements.