Benchmarking concretes with pozzolanic materials in terms of rapid chloride penetration test

Three pozzolanic materials-fly ash, granulated blast-furnace slag, and silica fume (both in densified and undensified forms)have been used as additives in the production of concrete. Rapid chloride penetration test (RCPT) was applied over the air-stored and water-cured specimens at the age of 90 days. The values of chosen variables-binder content, pozzolanic material content, and water-binder ratio (w/b))-were determined by using a statistical experimental design method. For each type of pozzolan used, 20 concrete mixtures were prepared, and a total of 80 mixtures were tested under each curing condition. By using the same statistical software used in design, it was found that pozzolanic material content was more significant than w/b on chloride permeability, particularly for water-cured concretes. Furthermore, the optimum amounts of pozzolans obtained for air-cured concretes were increased to higher levels when efficient curing was applied.