Effect of calcium chloride on the durability of pre-tensioned wire in prestressed concrete

Summary This paper gives in the first place an account of investigations which were made to determine the extent to which calcium chloride may be present in the free state in concrete at various temperatures, since this will have a bearing on the extent of corrosion of embedded steel. It has been concluded that while there is a tendency for a large proportion of the added calcium chloride to react with the hydrating cement at normal temperatures, the residual small amount of free chloride always retained in solution will give an appreciable chloride concentration in solution and will cause a certain amount of corrosion of embedded steel. The amount of free chloride in solution is influenced by the composition of the cement, and will increase with an increase in the amount of calcium chloride added and with increasing temperature. These conclusions offer a reasonable interpretation of some of the findings of the second part of the paper which covers a direct study of corrosion of high-tensile steel embedde...