Retrieving GBT mode amplitudes from shell finite element and finite strip results in first-order elastoplastic, bifurcation and vibration analyses

This paper presents a general post-processing procedure that enables retrieving GBT deformation mode amplitudes directly from shell finite element or finite strip results with a small computational cost. The procedure extends that for proposed in Cai (2019), in the context of bifurcation analyses, to all deformation mode families (conventional, shear and transverse extension), several analysis types (first-order elastic/elastoplastic and vibration) and problems with complex geometry (e.g., tapered or curved parts), which are difficult to analyse or cannot be analysed with GBT. Therefore, the unique GBT modal decomposition features, making it possible to acquire in-depth insight into the underlying mechanics, can be used even in complex problems. In order to demonstrate the accuracy of the proposed procedure, several validation examples are presented, involving problems for which “pure” GBT analyses can be performed. Finally, a set of application examples are provided, to show the capabilities and potential of this new approach.