Slag cement sulphate attack

As it can be concluded from the information relating to the chemical mechanism of cement paste corrosion under sea water, its resistance depends primarily on the Ca(OH)2 and calcium aluminates content it means that the resistance increases with the C-S-H phase content in the paste. Therefore cements poor in C3A, with low C3S/C2S ratio, that is those with high sihca ratio and low lime saturation factor show the best resistance. Cements with high slag and pozzolana content are extremely resistant, particularly when they are produced from clinker poor in C3A. Very good results were assured by the three component cements, with 30% pozzolana addition, beside of slag [98]. Calcium aluminate cement reveals, as in the case of sulphate attack, the highest corrosion resistance in marine environment (see Chap. 9). 

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