Comparison of Four Electrical Measurement Methods with Bulk Diffusion for Assessing the Chloride Resistance of Concretes

Abstract

This study is a comprehensive research that assesses the performance of four electrical measurement methods [Rapid Chloride Permeability Test (RCPT), Rapid Chloride Migration Test (RCMT), Surface Electrical Resistivity (SR) and Modified Rapid Chloride Permeability Test (MRCPT)] for evaluating the chloride penetration of concrete and compares the results with bulk diffusion method (BD). Due to the concern raised by some scholars about the effect of pore solution conductivity on some of these rapid tests results in the case of using supplementary cementitious materials (SCM’s), in this study silica fume was used in proportions of 7.5 and 15 %. All four methods showed significant reduction in the chloride permeability of samples containing silica fume compared to the control samples, over time. The reduction rate was significantly high for RCPT and SR methods and moderate for RCMT. The results showed that MRCPT had the lowest sensitivity to the replacement of cement with silica fume. Good relations were observed between results of RCMT and MRCPT with BD method.