Its popularity is due to its ready availability, low cost, predictable performance characteristics, and successful application over several decades. Concrete has to satisfy many performance requirements. Such knowledge permits judicious use of admixtures. Originally, the science of admixture was the province of a specialist, but with advanced building technology and ever increasing new demands on builder, engineer and architect it is necessary that all involved in building have as much knowledge of admixtures and their effects as of cement, aggregate or the mixing water. The amount of calcium chloride to be used for a particular job depends on the requirements, although it is generally recommended that the dosage should not exceed 2 per cent by weight of cement.
Calcium chloride is available as pellets or other granules, flakes, or in solution form.
The regular flake form contains a minimum of 77 per cent calcium chloride and the pellet and other granular forms a minimum of 94 per cent. If any lumps develop during storage they should be discarded. Calcium chloride is soluble in either cold or hot water. In making a solution it is good practice to add the salt to the water, for if water is added to the salt a hard coating forms, making dissolution slow. Freshly made, the solution is warm and should be cooled before use.