Reliability of Cold-Formed Steel Sections Subjected to Web Crippling

This study aims to evaluate the structural safety of cold-formed steel sections subjected to concentrated loads in regions without transverse stiffeners, susceptible to web crippling, and dimensioned according to the North American Specification (AISI S100) and the Norma Brasileira (NBR 14762 2010) standard. Experimental data from various sections reported in the literature were analysed, obtaining professional factor statistics. Target reliability indices commonly used in the calibration of cold-formed steel standards were considered. A reliability analysis according to the First-Order Reliability Method (FORM) was developed for several action combinations found in the AISI and NBR standards. In addition to the scenarios prescribed by the AISI (2016), a scenario for the NBR 14762 (2010) standard is proposed, which, although it does not yet exist in the standard, was adopted for research purposes. In the proposed scenario, it was discovered that the resistance factor stipulated by the NBR 14762 (2010) standard did not produce satisfactory outcomes regarding a target reliability index of 2.5 in 10 out of 25 examined cases.

Automated summary

This study evaluates the structural safety of cold-formed steel sections without transverse stiffeners subjected to concentrated loads, following the AISI S100 and NBR 14762 2010 standards. Experimental data from literature were analyzed, and reliability analysis using the First-Order Reliability Method (FORM) was conducted for various action combinations found in the standards. The study also proposes a scenario for the NBR 14762 (2010) standard, which showed unsatisfactory outcomes in meeting the target reliability index in 10 out of 25 examined cases.