SOLVENT REPLACEMENT STUDIES OF HYDRATED PORTLAND-CEMENT SYSTEMS - THEROLE OF CALCIUM HYDROXIDE

A study to determine the role of Ca(OH)<INF>2</INF> in hydrated cement systems concerning the processes involved in the removal of water by solvent replacement methods was conducted. The length change character istics of Ca(OH)<INF>2</INF> compacts containing varying amounts of wa ter and immersed in large volumes of organic liquids (methanol, isopro panol, benzene, and acetone) were analyzed and compared with those of hydrated cement paste. Inferences regarding the relevance of the Bangh am effect and possible chemical interaction with the solid as to the m echanisms responsible for length change were made. Dependencies of the latter on compaction pressure and solvent species are discussed. The implication of the results with<INF></INF> respect to microstructural investigations of cement paste are suggested. (C) 1998 Elsevier Scienc e Ltd.