Mechanical characteristics of sigma-profile hardening zones

The object of research is strips cut from a thin-walled cold-formed steel profile, sigma type cross section. The purpose of this work is to determine the yield strength and ultimate strength for each of the zones of the profile under study, as well as to adapt the existing normative methodology for calculating thin-walled profiles to account for hardening zones. Method. To determine the mechanical characteristics, the samples are tested on a bursting machine. The characteristics of the material are determined by stress-strain graphs. To calculate the bearing capacity of the profile, considering the effects of hardening, the effective width method is used. The specific engineering methodology complies with the construction regulatory documentation of the Russian Federation. Results. The values of yield strength and ultimate strength are given for each of the profile zones. Overload coefficients for hardening zones relative to ordinary zones are shown. A comparative analysis is given with the previously known results of other authors. According to the results of the engineering calculation of the bearing capacity of the profile, considering the hardening zones and without them, the possible effect of applying the research results is shown. © The Author (s) 2025