Silva – Impact of Accelerators and Retarders on the Hydration of Portland Cement
Denise A. Silva, Ph.D.
Research Manager. W.R. Grace – Conn., Cambridge, MA
The impact of variables such as cement chemical and mineralogical composition, particle size distribution, temperature and others on the mechanisms of Portland cement hydration and kinetics has been the subject of numerous researches over the past several decades. However, many questions remain unanswered. Understanding the mechanism of hydration in the presence of chemical admixtures imposes an additional challenge. Different theories and models to explain the impact of typical accelerators and retarders on cement hydration have been proposed. This article will review the literature on this subject focusing on common, typical accelerators and retarders such as chlorides and sugars. The current knowledge gaps that prevent understanding and modeling cement hydration in the presence of such admixtures will be discussed.