Experimental analysis on the combined effects of corrosion and fatigue in reinforced concrete beams

Resumo

Infrastructure elements, especially reinforced concrete bridges and viaducts, are exposed to a combination of degrading processes throughout their life cycle, such as corrosion and fatigue. The combined effects of both processes are known to be more harmful to the structure than the sum of both deterioration processes considered individually. Due to the limited amount of studies in this field, this research aims to evaluate, by experimental analysis, the combined effects of fatigue and corrosion on reinforced concrete beams. Eight beams measuring 7 x 14 x 130 cm were cast and divided in four groups of 2 beams each: one group for reference beams, one for corroded beams with a loss of mass of 10%, one for beams subjected to 200,000 cycles and the last for corroded fatigued beams. The results show that the combined processes drastically reduce the load capacity of the beams by less than half compared to the reference beams. It was also observed that fatigue life decreased and the failure mode changed to fragile.