Reuse design of CFS columns subjected to interaction buckling for the application of circularity in construction

The embossments in cold-formed steel sections are a breakthrough to inhibit the buckling deformations. The embossments are minor corrugations in thin steel sections which are formed by a cold rolling process. This paper presents the test results of embossed cold-formed steel (CFS) angle sections. A total of 24 stub column tests were performed with various thicknesses, embossment patterns, embossment thicknesses and material strengths. The CFS columns are of constant length of 700 mm. The test results indicate that the local buckling capacity of the CFS sections increased and, in some sections, the local buckling deformations can be fully inhibited due to the presence of embossments. The results also indicate that the increase in embossment thickness increases the local buckling capacity while the yield strength decreases due to the change in material properties. This paper also discusses the appropriateness of using the Direct Strength Method (DSM) for the design of the embossed CFS section against local buckling. A new approach to modify the DSM method for accurately predicting the design strength is proposed.