Buckling of a sandwich beam with carbon nano rod reinforced composite and porous core under axially variable forces by considering general strain

Abstract

Scientists have explored alternative reinforcements to improve the mechanical properties of composite structures in recent years due to the high financial and environmental costs associated with the synthesis of carbon nanotubes and graphene plates. A sandwich composite beam reinforced with carbon nanorods (CNRRCs) synthesized from potato waste with a porous core is examined in this study. The nonlocal strain gradient theory and general strain theory are applied to this porous core structure under axially variable force. Based on the sinusoidal theory, shear deformation theory is used to calculate displacement fields of reinforced composite sandwich beams. Equilibrium sandwich beam equations are derived using higher order shear deformation theory. The mixture rule is used to determine the properties of the face sheet, including Young's modulus, shear modulus, and Poisson's ratio. A variable axial compression force is used to calculate the external work. Based on the Ritz method and different boundary conditions, the final equations are derived, and then the buckling and stiffness matrices are derived, and finally, the equations are solved and the critical buckling load is determined. An analysis of the critical buckling load for this structure is conducted using carbon nanorods made from potato waste. In addition, various parameters such as the strain gradient parameter, the non-local parameter, the volume fraction of carbon nanorods, and the thickness ratio are discussed. In this study, carbon nanorods made from recycled materials are found to increase the stiffness of sandwich beams and then increase critical buckling loads, which is lower than carbon nanotubes and more economical than carbon nanotubes. Graphene platelets and carbon nanotubes have a higher stiffness-to-cost ratio than carbon nanorods. Carbon nanorods, on the other hand, have a lower cost than graphene platelets and carbon nanotubes.