Buckling analysis for plates using finite strip method based on refined Mindlin–Reissner plate theory

Abstract

This paper presents a three-nodal-line finite strip formulation based on the refined first-order shear deformation plate theory (RFSDT) for the buckling analysis of both thin and thick plates. The proposed finite strip model incorporates the effects of transverse shear deformation, which leads to a significant reduction in the critical buckling stress of plates. Closed-form expressions for the strip stiffness and geometric stiffness matrices are derived using the principle of minimum total potential energy. These matrices enable more efficient structural stress analysis while reducing computational cost. The buckling problem is formulated as an eigenvalue problem obtained from the assembled strip stiffness and geometric stiffness matrices, from which the critical buckling load factors are determined. The results obtained using the proposed finite strip are validated through comparisons with exact solutions and previously published studies. Furthermore, based on an extensive parametric study, practical formulas are proposed for predicting the critical buckling stress of isotropic simply supported plates subjected to uniaxial compression and in-plane bending. The proposed formulas exhibit high reliability, as indicated by low coefficients of variation and high coefficients of determination.