Comparison of Postbuckling Prediction Approaches in Curved Panels

Understanding the second order inelastic behavior of structural elements requires proper application of nonlinear analysis methods. In slender elements, e.g. thin curved panels, the load vs. displacement curve shows a negative stiffness and the element releases strain energy to maintain equilibrium. In this study the theoretical backgrounds to different available approaches for numerical modeling and analysis of this kind of nonlinear behavior are reviewed. Then the buckling and postbuckling responses of three typical square slightly, moderately and highly curved panels under the action of pure shear loading are investigated by use of different static and dynamic approaches in the ABAQUS finite element package.

The results are compared, and the advantages and shortcomings of the methods are discussed. According to the results, the Riks method is found to be an adequate and justified technique for the proper investigation of the buckling and postbuckling behavior of thin curved panels and enables the true tracing of the complete load-displacement response from the initial linear elastic to the final nonlinear strain hardening and softening stages.