CRITICAL AIR-VOID SPACING FACTORS FOR LOW WATER-CEMENT RATIO CONCRETES WITH AND WITHOUT CONDENSED SILICA FUME

Abstract Normal Portland cement concretes with a water-cement ratio of 0,3 and concretes containing 9% condensed silica fume (CSF) at a water-cementitious material ratio of 0,3 were submitted to freeze-thaw cycles in water in accordance with ASTM Standard C 666. The CSF concretes were also submitted to freeze-thaw cycles in air at 100% relative humidity. For both types of concrete and both types of test, the values of the critical air void spacing factor were found to range between 300 μm and 500 μm. Air entrainment was thus needed to protect these concretes from frost damage.