This paper aims to analyze the free vibration response of functionally graded plates with complex cutouts. An isogeometric analysis method based on a novel quasi-three-dimensional higher-order shear deformation theory called the spectral displacement formulation (SDF) is employed to predict the free vibration characteristics of the plates. The SDF can deal with the three-dimensional elasticity solution and naturally avoid the shear-locking problem, making it suitable for plates with varying thicknesses. The governing equations for free vibration of the plates are derived using the D'Alembert principle and the principle of virtual work, and the equations are discretized using isogeometric method. The results of several numerical examples are compared with existing reference solutions. It is concluded that the proposed analysis method can accurately and effectively analyze the free vibration of functionally graded plates with complex cutouts.

functionally graded plate  /  cutout  /  spectral displacement formulation  /  isogeometric analysis  /  free vibration