Optimum limestone powder amount in mortars with over silica fume

摘要

The calcium hydroxide (CH) and the calcium silicate hydrate (CSH) are the main hydration products of Portland cement (PC) paste. The CH product causes the durability problems in the PC paste due to the leaching Ca2+ ions. Silica fume is an effective pozzolan to consume CH in the PC paste. It is only effective to convert all CH to CSH if used in excessive amounts in the PC paste. Some problems arise related to segregation, mechanical or physical properties when it is used in excessive amounts. In this study, the optimum limestone powder amount was determined to improve these problems in the mixtures.