In this experimental study, the corrosion characteristics of steel reinforcement bars embedded in concretes, which were produced by incorporation of metakaolin obtained from high purity metakaolin or calcined raw kaolins, were investigated. The linear polarization resistance (LPR) method was benefited as the corrosion monitoring method. In concrete production, 0.40 water/binder ratio, 350 kg/m3 total binder amount, two different mineral admixture replacement levels of 5% and 15% were used. In addition, control samples were produced to evaluate the effectiveness of mineral additives. Reinforced concrete samples manufactured for accelerated corrosion monitoring were submerged into NaCl solutions of two different concentrations (2% and 5% solutions) to provide rapid anodic reactions in corrosion process. Additionally, the electrical resistance values of the concretes were tested to assess the corrosion behavior. After the experimental results were achieved, the obtained data were evaluated statistically and a new mathematical estimation model was developed using the gene-expression programming (GEP) method taking into account the effective parameters. This model was also compared with the results of the multiple linear regression, which is a statistical method. The analysis of the results based on LPR technique showed that the modified samples yielded higher corrosion resistance than the plain samples in both solution exposure conditions. Among the mineral additives used, it was observed that those with metakaolin addition had the highest resistance. While the coefficient of determination (R2) of the testing set produced for the GEP prediction model was around 0.9, the value obtained by multiple linear regression was found to be 0.433.
