Porous structures, known for their lightweight nature and tailorable mechanical properties, play a pivotal role in aerospace, automotive, and biomedical applications. Among these, circular plates with spatially varying porosity are particularly susceptible to buckling under compressive loading. This study examines the mechanical buckling behavior of functionally graded porous circular plates with radially varying porosity subjected to a uniformly distributed radial load. Two boundary conditions—simply supported and clamped edges—are considered. The governing equations are derived using first-order shear deformation theory (FSDT) to incorporate transverse shear effects and are solved analytically using a semi-exact Fourier–Bessel series expansion method, which offers a computationally efficient and accurate alternative to numerical approaches. The proposed formulation is validated through finite element simulations and benchmark results from the literature. The results highlight the distinct influence of radial porosity variation on structural stability, revealing that the critical buckling load is highly sensitive to the porosity distribution, plate geometry, and boundary conditions. Plates with reduced porosity toward the outer edge exhibit significantly enhanced buckling resistance, while clamped boundaries increase the critical load by 35–50 % over simply supported cases. The proposed method offers a practical and reliable framework for analyzing radially graded porous plates and provides a foundation for future studies involving coupled mechanical, thermal, or dynamic effects.
