114 Damage to concrete structures
5.2.2.3 Mitigation
Although the damage mechanism in the case of salt scaling is totally different from the mechanism causing internal frost damage, better resistance
can be obtained also in this case by reducing the water/cement ratio and by
adding air entrainment.
5.2.2.4 Example
Frost scaling typically occurs on concrete roads and pavements exposed
to de-icing salts. Figure  5.12 shows the resultant damage pattern in the
case of a local concrete road exposed to de-icing salts in winter time. Due
to traffic loading, the degradation of the concrete road can continue even
after winter ends.
5.2.3 shrinkage
Over the long term during service, drying shrinkage can lead to progressive crack formation in concrete structures. Although the process of drying
shrinkage is much slower at the later age, the mechanism and influencing parameters are the same as for drying shrinkage during hardening.
Reference is made to Section 4.3 ‘Drying shrinkage’ in Chapter 4.
When the environment contains carbon dioxide, as is the case for
the atmosphere, another type of shrinkage, the so-called carbonation
Figure 5.12 Salt scaling on a concrete road.