The effect of cement, mineral additive and aggregate types on the fresh and hardened concrete properties of self-compacted concretes

In this thesis work, effects of 2 types of aggregates, 3 types of cements and 2 types of mineral additives on self-compacting concrete (SCC) were studied. For this purpose, 12 groups of SCC were produced. Basalt and limestone as course and natural sand as fine aggregate were used. Mixture grading curves are kept the same for each were concrete. CEM I 42,5 R, CEM II/B-M (L-W) 42,5 R, CEM III A 42,5 N cements used in SCC productions for each aggregate group. C55/67 strength class was timed for the mixture design. At the first group of produced SCCs using limestone aggregate, at least a slump spread of 60 cm is targeted by keeping cement and plasticizer dosages constant at 550 kg/m³ and 1%, respectively. Total cementitious material amount was arranged as 350 kg/m³ of cement and 200 kg/m³ of fly ash at the second group mixtures. At the third group, ground granulated blast furnace slag (GGBFS) was used instead of fly ash. As 100 kg/m³ of fly ash and 100 kg/m³ of GGBFS, total cementitious material amount is kept constant at the final study. In the last mixture, 100 kg/m³ of fly ash and 100 kg/m³ of GGBFS were used besides 350 kg/m³ of cement. In each SCC group, 9 cylinders of 100/200 mm size and 2 cubes of 150x150x150 mm sized were produced. The specimens were stored in a curing pool at the temperature of 20 ± 2°C. Slump flow spread and T500, hydration temperatures, pH, unit weight, air content, and setting time on fresh concrete were tested on SCC mixtures. As hardened concrete experiments, 7th, 28th and 90th days compressive strength and 28th day water penetration under pressure and chloride permeability tests were performed. As a result, initial-final setting times and pH values obtained were longer and higher for basaltic SCC than those of the limestone SCC, respectively. It was obtained that the basalt - based SCC was more impermeable than limestone - based SCC. Compressive strength of limestone - based SCC remained under that of basalt – based ones and even limestone - based SCC reached the 28 - day strength of basalt – based one at the age of 90 days.