Enhancing the Properties of Sulfate-Resisting Cement

Abstract

Sulfate-resisting cement is used in construction works when a sulfate attack is probable. This type of cement withstands sulfates due to its low C3A content. On the other hand, the decrease in the quantity of C3A leads to a reduction in the rate of early strength development. To overcome this problem, a hardening accelerator was added to the cement mix. To estimate the effect of the accelerator on some properties of hardened cement, compressive and flexural strength, and drying shrinkage tests were carried out. Four series of cement mortar mixes were made. The hardening accelerator was not added to the control series, while it was added to the others with three different percentages (of cement mass) of 0.5, 1, and 1.5%. The results revealed that the hardening accelerator enhances the compressive strength of all mortar ages while it slightly promotes flexural strength only at early ages. It was also observed that the hardening accelerator strongly inhibits the drying shrinkage strain.

Keywords

• sulfate-resisting cement
• hardening accelerator
• flexural strength
• compressive strength
• draying shrinkage