Avaliação da durabilidade de concretos produzidos segundo a ABNT NBR 6118:2007 e expostos aos cloretos disseminados em névoa salina na Praia do Futuro, em Fortaleza–CE

Abstract

The reinforced concrete structures in regions of coastline degrade earlier than those further away, due to the action of chlorides present in sea salt spray, responsible for triggering the process of corrosion of steel reinforcement in concrete. This study evaluated the monthly deposition of chlorides present in the marine atmosphere as a function of distance to the sea in Praia do Futuro, in Fortaleza, using the method of wet candle. It was also evaluated the action of chlorides in concrete using specimens with fck 25 MPa and 35 MPa, by measurement of the chlorides content penetrated and corrosion potential. For each fck of concrete were made four specimens, which were distributed in distant locations of 100 m, 300 m, 740 m and 1000 m from the sea, accompanied by a wet candle. Laboratory trial was conducted accelerated chloride penetration and corrosion potential in order to compare with the results in natural conditions. The results indicate that the aggressiveness of the environment in this region is quite high compared with other regions of Brazil, and also decreases exponentially with the distance from the sea. The concrete produced with lower water/cement ratio and greater fck perform better against the aggression of Praia do Futuro. It was verified the need for special attention in the development of future projects of reinforced concrete structures for this region as the ABNT NBR 6118:2007 and ABNT NBR 12655:2006.