Evaluation of chloride deposition using the wet candle method: a study in the city of Cabo Frio, RJ

Abstract

In a context of durability design of reinforced concrete structures, it is necessary to establish the divisions of the aggressiveness classes of the different maritime and coastal environments, in order to contribute to the study of the classification of environmental aggressiveness. In this paper, the deposition of aggressive ions and the general climatic aspects of the coastal region of the city of Cabo Frio, RJ are evaluated. For the analysis, the wet candle method (Brazilian NBR 6211:2001) was adopted. The exhibitions were held at five different points throughout the city, each with three wet candles. To quantify the chloride content, the conductimetry method was used, which is done by measuring the electrical conductivity of an electrolyte solution, due to ion migration. The results point to a high level of chlorides in the initial range of distance from the sea and a considerable decrease from approximately 900 meters from the seashore. In this way, it was possible to verify that the city, in its interior, is under moderate to minimal aggressiveness. In the initial distances of the seashore, there is high aggressiveness. These results show the importance of considering micro exposure environments during the design phase of reinforced concrete structures.