Buckling Optimization of Stiffness Varied Isotropic, Anisotropic, and Sandwich Panels

This study examines the buckling performance of lightweight panels with spatially varying stiffness distributions. Three design strategies were explored to vary the stiffness of a panel: thickness variation, modulus variation, and fiber angle variation. These strategies were applied to an isotropic and anisotropic set of panels. A semi-analytical framework based on Classical Plate Theory and the Rayleigh-Ritz method was developed to predict the critical buckling loads for arbitrarily varying stiffness profiles. The design space was parametrized using Fourier series and optimized through single- and multi-objective formulation to balance buckling performance and structural mass. The optimization results demonstrate that spatial tailoring of stiffness can significantly enhance the buckling capacity by over 50% for certain case studies. Overall, this work establishes a foundation for designing lightweight, buckling-resistant structures by exploiting geometric and material gradation, offering valuable insights for future applications in advanced additive and composite manufacturing.