Freeze-thaw durability of activated blast furnace slag cement concrete

The results of freeze-thaw testing (ASTM C 666) and the analysis of the air-void parameters (ASTM C 457) of activated blast furnace slag cement (ABFSC) concrete mixes using sodium carbonate and sodium silicate activation are presented and discussed and compared with the results obtained from testing a conventional ordinary portland cement (OPC) concrete mix. The results from both normal moist-cured specimens and heat-cured specimens are presented. A full range of air content categories were examined. All concretes examined incorporated a water-to-binder (w/b) ratio of 0.44 and a binder content of 420 kg/m(3). Results demonstrate that the AEA used was effective at entraining air with excellent characteristics in the sodium silicate ABFSC concrete, but at dosages much higher than required for OPC concrete. The durability of this concrete was high and similar to that of OPC concrete. The characteristics of the air-void system in the sodium carbonate ABFSC concrete were poor and durability performance was generally low. The workability of all ABFSC mixes improved over the full range of air contents similar to OPC concrete. In all cases freeze-thaw performance, both with respect to durability factor and loss in mass due to specimen scaling, was observed to be generally dependent on air content and air bubble spacing factors.