Understanding Salt-Frost Durability in Concrete: The Role of Concrete Mix Parameters
Photo credit: Betoniteollisuus archives
In Mian Ammar Shafqat’s master’s thesis, the salt-frost resistance of concrete has been investigated with respect to both surface scaling and internal damage. The study comprised 14 different concrete mixes in which the cement type, water-to-binder ratio, and air content were varied. The test results show that air entrainment has a highly significant effect on surface scaling in the slab test; air-entrained and non-air-entrained concretes produce scaling values at entirely different levels. The waterto-binder ratio and cement type also had a notable effect on the scaling value, particularly for air-entrained concretes. Regarding internal damage, air entrainment likewise had a substantial effect. Air-entrained concretes showed no internal damage regardless of cement type or water-to-binder ratio. For non-air-entrained concretes, the water-to-binder ratio also influenced the degree of internal damage. The P-factor of infrastructure concretes correlates well with the scaling value from the slab test. The P-factor accounts for the parameters included in the thesis, namely binder composition, waterto-binder ratio, and air content. Based on the test results, the P-factor method captures the influence of these parameters reasonably well.
