Influence of Cement Composition on Concrete Durability

This paper reviews the effect of cement composition on corrosion, sulfate attack, alkali-silica reaction, thermal and shrinkage cracking, and cracking due to unsound cement. Cement composition significantly affects the durability performance of concrete. Pore fluid studies and x-ray diffractograms show that C3A partially removes disolvable corrosion-inducing chlorides from the pore solution by forming Fiedel's salt. Accelerated corrosion tests and exposure site data on concrete specimens show the practical significance of chlroide binding by the C3A phase of cement. Corrosion initiation time, time-to-cracking of cover concrete, and chloride threshold values were found to increase systematically, whereas metal loss from reinforcement decreased as the C3A content of the cement increased. These and other findings are presented.