Per §8.5.2, freezing of water in HARDENED concrete is estimated to exert internal pressure of approximately:

1. §8.5.2: 'It has been estimated that freezing of water in hardened concrete could exert pressures of about 140 Kg per sq cm and if strength of concrete is less than this it could get damaged severely.' 2. Damage accumulates with freeze-thaw cycles, especially in members wet on more than one face. _Source: IGNOU ET-522 Block-2 Unit-8 Durability of Concrete, §8.5.2, p. 74_