Vibration and sensitivity analysis of porous FGM sandwich plate using improved FSDT-based isogeometric method

This paper employs an improved first-order shear deformation theory (IFSDT) for the vibration analysis of a porous functionally graded sandwich structure. Isogeometric analysis (IGA) is employed, utilizing NURBS basis functions to ensure higher-order continuity of the approximation space, thereby facilitating a smooth and accurate solution representation. The proposed framework incorporates a polynomial shear correction function, providing a more accurate solution compared to the conventional FSDT. The kinetic equations of motion are solved using Hamilton’s principle to ensure continuity in displacement and transverse stress at the interfaces. A thorough investigation of the free vibration responses and central deflection is conducted by varying the thickness ratio, power-law indexes, porosity, and sandwich configuration along with numerical validation based on isogeometric formulation of IFSDT. Furthermore, a global sensitivity analysis is performed to systematically quantify the relative significance of uncertain input parameters on natural frequencies and deflection behavior. The results demonstrate that the IFSDT–IGA framework enhances the accuracy of vibration analysis for porous FGM sandwich structures. The following investigation with the sensitivity analysis results provides valuable insights for the accurate design and optimization of next-generation lightweight structural components.