Corrosion behaviour of rebars 1.4003 in cracks of RC structures containing chlorides

The durability of chloride exposed reinforced concrete components is decisively determined by the corrosion behaviour of the reinforcement in the crack containing chlorides. In this case, high corrosion rates may occur using conventional rebar steel, which can lead to a significant cross-sectional loss of the rebar in a short period of time. One possible way to minimise the risk of corrosion in cracks containing chlorides is to use stainless rebars. Here, mostly expensive stainless steels of the material numbers 1.4571, 1.4401 etc. are used. An efficient alternative is the use of Chromium reinforcing steels (e.g. X2CrNi12) 1.4003. Corrosion tests on cracked reinforced concrete beams with chloride exposure and different chloride concentrations have been carried out in the laboratory of the University of Applied Sciences in Munich. The results of these investigations show a significant increase of the critical corrosion inducing chloride content of the rebars within the cracks. These results will be discussed in regard of the durability of reinforced concrete structures with Chromium reinforcing steels and cracked RC-structures in parking decks and floor slabs.