Deicer Salt Scaling Resistance of High Strength Concretes Made With Different Cements

Abstract

Seventeen concrete mixtures were prepared to evaluate the deicer salt scaling resistance of some high strength concretes with a 28 days strength in the 60-90 MPa range. A 0.30 water/(cement + silica fume) ratio was used for most of the mixtures and 3 additional mixtures were prepared with a 0.26 water/(cement + silica fume) ratio. In the 0.30 mixtures, two types of cements and a silica fume were used (Type III, Type III + 6 percent silica fume, Type I + 6 percent silica fume), and in the 0,26 mixes, only Type I + 6 percent silica fume. All specimens were submitted to 150 daily cycles freezing and thawing in accordance with ASTM C672, using sodium chloride as a deicer. For all concretes, the weight loss after 50 cycles was lower than 0.75 kg/m (squared) and under 2 kg/m (squared) after 150 cycles, and no clear relationship was found between the scaling resistance and the spacing factor. Based upon results in this study, and in others, it seems that the use of a water/(cement + silica fume) ratio of 0.30, a good quality coarse aggregate and a portland cement with silica fume generally allows the production of non-air-entrained concretes with a good deicer salt scaling resistance, even after only 24 hours of curing. It is also possible, with certain Type III cements, to produce deicer salt scaling resistant non-air-entrained concretes without using silica fume.