BUCKLING MODES OF DOUBLE-CHANNEL COLD-FORMED BEAMS

The present paper starts from the analysis of previous experimental re sults on double-channel cold-formed beams subjected to local and later al-torsional buckling. The scope of this reanalysis is to identify the range of definition of the bucking modes, which influence the ultimat e behaviour of such beams. The verification approach of EC3 and AISI h ave been compared to the experimental results, giving a satisfactory a greement. The definition fo coupled instability range has been set up by means of EC3 formulations. The proposed equations relate together t he main geometrical parameters of the beam, giving useful indications to the designer.