Abstract

This paper studies the bending behavior of steel elements of hollow structural sections (HSS), subjected to effects of cycle ultra-low fatigue (FUBC). The FUBC phenomenon is present when the strength exceed the yield of the material, producing a decrease in its strength each time the same displacement is achieved. The cycle ultra-low fatigue effect can affect civil structures such as eolic towers and o fshore structures. Experimental tests and numerical simulations are presented using the Concentrated Damage Model (MDC). The MDC is based on the theory of plasticity and mechanics of continuous damage. The results obtained numerically can be compared with the experimental ones, having the calibration of model parameters and an adequate behavior. The permanent deformations and the level of damage in the HSS profile are results obtained as numerical simulation. The level of damage, physically representing the degree of local buckling that presents the HSS element, which is slight and its load drop due to repetitive displacements.