Some mechanical and durability properties of self-compacting concrete with recycled aggregate containing different mineral additives

The aim of the study is to design and produce self-compacting concrete (SCC) by using different proportions of recycled aggregate (RA) and mineral additives, to determine some of the fresh and hardened properties of these concretes, and to investigate the behavior of these concretes at high temperatures. For this purpose, SCCs were produced by replacing coarse RA and fine RA with normal coarse and fine aggregate at 35%, 70% and 100% ratios and these were compared with SCC without RA. Mineral additive used at the rate of 30% of the total binder in the design; 30% fly ash, 20% fly ash + 10% metakaolin, 20% fly ash + 10% silica fume and 20% fly ash + 5% metakaolin + 5% silica fume were arranged in four different combinations. The tests carried out on fresh concrete were slump flowing, T500 time, J ring and sieve separation. Testing of compressive strength, splitting tensile strength, flexural strength, Bohme abrasion, determination of dynamic elasticity modulus, rapid chloride permeability, capillarity, maximum water penetration depth under pressure and ultrasound transmission velocity tests were carried out on the hardened concrete. These concretes were exposed to 200oC, 400oC, 600oC and 800oC and their behavior under high temperature was investigated by performing compressive strength and ultrasound transmission velocity tests. The ANOVA test shows that there is no significant difference in the properties of 35% coarse RA and 35% fine RA substituted concretes compared to those without RA. It can also be concluded that concretes containing 10% silica fume and 5% metakaolin + 5% silica fume perform best.