Postbuckling of Thin-Walled Composite Laminated Beams – Analysis by the Generalized Beam Theory

• Applicant: Professor Dr.-Ing. Christian Mittelstedt
• Subject Area: Lightweight Construction, Textile Technology ; Mechanics
• Term: since 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 558736878

The present project proposal is dedicated to the analysis of the interactive stability behaviour, i.e. the simultaneous occurrence of local and global as well as distortional stability cases, in thin-walled composite laminated beams under different boundary conditions and load scenarios. While the stability behaviour of classic isotropic bars and beams is essentially understood and many analysis methods are available for the analysis of purely local and global stability cases, the treatment of anisotropic composite laminated beams raises a large number of questions when considering interactive buckling and, above all, the postcritical behaviour (‘postbuckling’), which the planned project will be dedicated to clarifying. In addition to illuminating the influences of laminate-typical coupling effects and transverse and inplane shear strains, this also includes the provision of analysis methods that allow efficient and yet highly accurate analysis of the interactive stability of such laminate structures. The planned project aims to extend the so-called Generalized Bending Theory (GBT) to the analysis of the buckling and postbuckling behaviour of composite laminated beams, using a hierarchical approach from simple to increasingly complex tasks. The current state of research shows that there is still a considerable need for research in this area and that the use of GBT with regard to the stability of composite structures in general and composite laminated beams in particular especially for postbuckling analysis has particular potential.

• DFG Programme: Research Grants