Paper by MEMON from ISCR 7th 1994 Vienna Austria
Requirements for concretes in colder environments are stricter than those normally requested for standard commercial concretes. Therefore, a concrete produced with (i) high quality ingredients, (ii) a water/cement ratio of 0.35 to 0.40 by mass, (iii) 3.0 to 6.0 percent entrained air, (iv) an adequate maturity, i.e. when the compressive strength reaches about 28 N/mm 2 before freezing, and (v) a 28 day compressive strength of at least 35 N/mm 2 is considered satisfactory. The above stipulated suggestions may be conservative, but this is acceptable because the cost of removing concrete pavements once they show freeze-thaw damage is very high.