Evaluation of the Software’s Reliability in Solving the Buckling Problem of the Cold-Formed Plain C-Section Member Bending About Its Asymmetrical Axis

The elastic buckling moment of the cross-section of the thin-walled member is the value to be determined during the calculation of the direct strength method (DSM), which is mentioned in design standards AISI S100 and AS/NZS 4600. This value is calculated by software such as THIN-WALL-2, CUFSM 5, and GBTUL. To obtain a reliable buckling moment, software needs to be tested not only at the design stage but also continuously during use. There are methods of checking software output, including checking against theoretical solutions or comparing the outcomes of software with each other or with those of reliable software. Applying the second procedure, the article compares and evaluates the calculation results of THIN-WALL-2, CUFSM 5, and GBTUL on 16 Lysaght cold-formed C-sections subjected to bending about the asymmetrical axis, then compares them with those of ABAQUS. The content of the comparison includes the main buckling mode, the elastic buckling moment, the half-wave length, and the signature curve. Research shows that the calculation results of THIN-WALL-2 are in best agreement with those of ABAQUS.