Calcium chloride has a wide range of uses, can be used as a desiccant, can also be used in concrete, used in each industry has a different role. Concrete can be found everywhere in all corners of our lives, concretelyThe role of calcium chloride in concreteThere are three aspects: physical properties, chemical properties, and mechanical properties play a key role.
1.Solidification time
Calcium chloride is mainly used as a quick-setting agent for concrete, which can greatly shorten the initial and final setting time of concrete. It is mainly used when the temperature is low, which helps to speed up the concrete pouring and obtain the finished concrete slab as soon as possible. However, it is not recommended to use a quick-setting agent in hot weather conditions, otherwise the concrete will set quickly and it will be difficult to complete the concrete pouring smoothly.
csa a266.2-1973 and ASTM C494-1971 require that the initial setting time after calcium chloride should be at least 1 hour (but not more than 3 hours [CSA] or 3.).5 hours [ASTM]).
2.Water-cement ratio
Calcium chloride does not significantly reduce the amount of water required to achieve a given slump, nor does it have a dominant effect on concrete strength. As a quick-setting agent, it hardens concrete prematurely and reduces water leakage.
3.Bleed-in
The use of calcium chloride in concrete does not have an air-entraining effect, but when used with air-entraining agents, it helps to reduce the amount of air-entraining agents and produce more gases.
4.Freeze-thaw
Concrete made of calcium chloride hardens quickly and is quickly freeze-thaw resistant. This is important because it may be necessary to use de-icing salt for the material when concrete is poured in winter. The frost resistance of mature concrete containing calcium chloride may be reduced at a later stage.
5.Dry shrinkage
It is well known that calcium chloride will increase dry shrinkage, and the amount of dry shrinkage depends on the amount of calcium chloride added, the type of cement, the curing time and environmental conditions.
6.Panuthin
Due to the use of calcium chloride, in some cases, white precipitates form on the surface of the cured concrete. However, under normal conditions, this white precipitate absorbs water and does not cause panthinning like other salts. These white precipitates are insoluble in water and can be removed using dilute hydrochloric acid.