Local and global vibration analysis of thin-walled steel frames using Generalised Beam Theory (GBT)

摘要

This paper reports the results of an ongoing investigation on the use of Generalised BeamrnTheory (GBT) to analyse the vibration behaviour of thin-walled steel frames. After a brief overview of the mainrnconcepts and procedures involved in performing a GBT vibration analysis, the formulation and implementationrnof a GBT-based beam finite element are presented, namely the determination of the finite element and framernlinear and geometric stiffness matrices, as well as the frame mass matrix (incorporating the influence of thernloading and frame joint configurations). Finally, in order to illustrate the application and capabilities of thernproposed GBT-based finite element formulation, numerical results concerning the local, distortional and globalrnvibration behaviour of a symmetric portal frame are presented and discussed. For validation purposes, mostrnGBT-based results are compared with values obtained by means of shell finite element analyses carried out inrnthe code Ansys.