Strength Tests and Design Methods for Cold-Formed Channel Columns Undergoing Distortional Buckling

摘要

The columns of industrial steel storage rack structures are generally cold-formed open sections manufactured either by roll-forming or brake-pressing. The commonly used sections are thin-walled lipped channels whose width and depth are approximately equal. Depending on the length of the columns and the restraints provided by pallet beams and bracing, these types of sections may fail in a mode of local, distortional or flexural-torsional buckling. In the report, the results of compression tests of thin-walled channel section columns formed by brake-pressing are described. Detailed measurements of the stress-strain characteristics of the material forming the sections are also described. Design methods to account for the inelastic behavior in the distortional mode of buckling are proposed in the paper and compared with the test results.