Relationships between compressive strength of cement-slag concretes under air and water curing regimes

Twelve concrete mixes were prepared. The mixes were made using binder contents 380 and 500 kg/m3 and classified into three groups including OPC, OPC-slag and slag concretes. Each group includes 4 mixes and the specimens were cured in curing regimes ac and wc. The highest strength was obtained at later ages as 80 MPa for OSC380-wc. It was revealed that wc is the optimum for all groups in the whole duration of 3-90 days. It was proved that an exponential relationship exists between the strengths obtained in ac & wc conditions for all groups. It was found that higher strengths can be obtained using lower binders’ contents for the specimens cured in water; this is a new finding with highly importance; meaning that for producing higher strengths it is not a necessity to use more binders. All the mixes were made for water-binder and sand-binder ratios as 0.33 and 2.25, respectively.