Image analysis of concrete surface for investigating the influence of aggregate distribution and load induced damage on the chloride permeability of concrete measured using RCPT (ASTM C1202)

In the present study, the influence of aggregate distribution and load induced damage on chloride permeability of the concrete, was investigated using image analysis of concrete surface. Two mixes of water to cement ratio of 0.45 and 0.55 were used. Chloride permeability of the concrete, measured using RCPT (ASTM C1202), was modelled considering the three phases- mortar, coarse aggregate and ITZ. Image analysis program Image} was employed to analyse the geometrical parameters of the aggregates and load induced damage measured at the concrete surface. Damage in concrete disc specimen (dia. 100 mm and depth 50 mm) were introduced using compressive and splitting tensile stress. Results showed that the prediction of chloride permeability, based on 3 phase modelling, agreed well with the experimental data. The present approach can be utilized for quick and economical assessment of in-situ concrete durability and local variations due to the influence of aggregate distribution and load induced cracks.