A frost-resistant concrete is a composite resistant not only to low temperatures, but also to water freezing in low temperatures. There are capillaries in each mortar, in which water accumulates. Low temperature makes the water freezes, thereby increasing its volume and bursting capillaries and, consequently, the concrete. Mixing frost-resistant concrete is primarily associated with two activities. The first one is to create a composite with a low water-cement ratio. While the second is adding thereto a special aeration admixture. It causes the formation of additional air bubbles in a concrete’s structure, not aggregating with each other, that brake the capillary. Lack of capillaries is equal to much smaller amount of water in the composite, and this water, which has got into the concrete already, may be pushed into the empty bubbles during freezing process. These bubbles are very small, with diameter less than 0.5 mm, and they are fairly evenly distributed. Unfortunately, preparation of frost-resistant concrete may cause some troubles for inexperienced persons. Well, the amount of aeration admixture to be added to the concrete, is based on several criteria. These are mainly the type of cement, water-cement ratio, temperature of the concrete, type of aggregate and other mineral additives. For this reason, preparation of frost-resistant concrete should be preceded by carefully reading the instructions of the manufacturer of cement and admixture itself, or outsource the work to a specialist or construction company.
