Effect of granulated furnace slag on properties self-compacting concretes

Reserves of natural raw materials decrease and negative effect on environment occurs since natural aggregates have been usually preferred. Concrete contains about 70-80% aggregates in volume. So, to protect natural raw materials alternative ways are needed. Granulated furnace slag is a by-product that has been widely used in concrete and cement sectors. It can be used both for cement as replacement and for aggregate in concrete. In literature, studies exist about the usage of granulated furnace slag as aggregates in concrete as partially replacement and asphalt surface application. By this way, granulated furnace slag causing environmentally problem finds a usage area to eliminate its negative effect. In this study, granulated furnace slag was used as fine aggregate in the ratios of 0%, 25%, 50% and 75% to produce concrete with 400 kg/m3 cement, 100 kg/m3 fly ash and 0.45 w/c ratio. Fresh concrete properties and hardened concrete properties at 7, 28 and 90 days were studied. Unit weight of fresh concrete, slump-flow, T500 time, J ring, V funnel and rheological properties were measured. On hardened concrete, unit weight, compressive strength, Schmidt hardness, ultrasound, capillarity and elasticity modulus were determined. According to results obtained, when it is used at the ratio of 25% and 50% workability of fresh concrete increases while compressive strength decreases.