Predizione della capacità portante di elementi con sezioni snelle soggetti ad azione assiale eccentrica. Parte 1: il metodo

The use of thin walled cold formed steel members as structural elements has become increasingly widespread over the last few decades. Due to the imperfections and high slenderness values found in plate elements (walls) making up members, column and beam-column performance is generally influenced by local buckling, which in many cases can interact with the stability of the overall members. This complex interaction is not taken into consideration directly in the most recent design standards, which in many case leads to a conservative assessment of the load carrying capacity of the members. This paper presents a procedure for predicting the load carrying capacity of thin walled cold-formed members under eccentric axial load. Both local and overall buckling phenomena can be taken into account by defining a suitable cross-section which is effectively resistant. The extensive validation phase is presented in the companion paper.