Latest developments on the analysis of thin-walled structures using Generalised Beam Theory (GBT)

This paper presents an overview of recent advancements concerning the derivation and application of Generalised Beam Theory (GBT) formulations for thin-walled members and structural systems and originating from the so-called "Lisbon research group". These advancements concern (i) the determination of the cross-section deformation modes for restrained members and curved members with circular axis, (ii) frame joint modelling and (iii) the formulation of a geometrically non-linear GBT. Several numerical examples are presented to illustrate the application and show the capabilities/potential of the proposed developments, concerning (i) the calculation of bifurcation loads and buckling modes, (ii) the calculation of undamped natural frequencies and vibration mode shapes and (iii) the assessment of interactive post-buckling behaviour of cold -formed steel members. It is concluded that GBT provides very accurate solutions with a small computational cost and that the unique GBT modal features can provide a deep mechanical insight into the problem under consideration.