The “Miracle” of Post-Buckled Behaviour in Thin-Walled Steel Construction and its Breathing-Induced Limitation

Thin-walled construction represents a powerful tool for saving steel and thereby for increasing the competitiveness of steel structures. However, on the other hand, as the limit state of thin-walled structures is substantially affected by stability phenomena, the above concept can be implemented just on the condition of post-buckled behaviour being taken into account in the solution to these stability phenomena. The paper first briefly studies the factors on which the intensity of the very favourable post-buckling reserve of strength depends and then in detail turns attention to the most important among them, viz. the effect of the cumulative-damage process that becomes manifest in the case of bridges and other systems subjected to many times repeated loading.