Cold weather concreting
Placing and protecting concrete when low temperatures slow strength gain and freezing threatens to permanently damage fresh concrete.
What does cold weather concreting mean?
Concrete that freezes before developing enough strength suffers irreversible internal damage that no amount of later curing repairs. Protection measures include heating mix water and aggregates, dosing accelerators, insulating with blankets or heated enclosures, and paying particular attention to edges and corners that lose heat fastest. Removing protection too abruptly causes thermal shock cracking, so the end of protection is managed as carefully as its start.
In practice
Winter work means the forms stay up longer, the schedule stretches, and someone has to check the blankets on Sunday.