Durability of concrete blended with micronized sands

In this study, micronized sand (MS) is selected as replacement of Portland cement to reduce the amount of cement used in concrete. This filler is considered as chemecally inert to water and hydration products. However, this material can influence the microstructure, affect the transport property and eventually change the service life of concrete structures significantly. In this paper, rapid chloride migration (RCM) tests are carried out. Chloride migration coefficients of concrete samples with and without MS are measured. The results, obtained from a wide range of finenesses (between 2400 and 13000 cm2/g) and replacement levels (10% to 30%), show that migration coefficients of concrete samples with and without MS are different. The DuraCrete model is applied to predict the service life of structures made with this blended material. Migration coefficient of samples with 30% replacement increased and the required cover thickness of the structure to be increased in order to have 100 years’ service life.