Fuzzy logic for estimating chloride diffusion in concrete

Chlorides are the agents responsible for starting the process of corrosion of steel reinforcement, thus reducing the service life of concrete structures, especially in marine environments. The penetration of chloride ions depends on several factors linked to the nature of the concrete cover and the exposure environment. The diffusion coefficient may establish the depth of chloride penetration in concrete in a given time and therefore this coefficient is related directly to the service life of reinforced concrete structures. This paper presents a methodology for determining the chloride diffusion coefficient using a mathematical model based on fuzzy logic. The following parameters were considered in the modelling: water/cement ratio, concrete compressive strength and the temperature during mixing of the concrete. The results show the feasibility of using fuzzy logic for the development of models to estimate the chloride diffusion coefficient in concrete.