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Author
Wojcik, G. S. | Feldman, K. L.
Title
X-Ray Absorption Measurements of Water Loss from Curing Mortar and Paste Samples With and Without Fly Ash.
Coporate
National Institute of Standards and Technology, Gaithersburg, MD
Journal
GNI Newsletter, 1-1, August 2003
Keywords
x-ray absorption | curing | mortar | cement paste | fly ash
Abstract
Proper curing of cement-based materials will help to develop a discontinuous pore structure that will aid in extending a structure's service life by reducing water and ion ingress. Recent work with an X-Ray absorption system has shown that cement pastes with fly ash lose more water during early curing than those without fly ash, indicating a higher porosity. Also, pastes were shown to lose more water than mortars. These studies used specimens that may be too small to be representative of larger structures. In this study, water loss from paste and mortar specimens, with and without flyash, that are more than 10 times as large as those used in previous studies is determined with an X-Ray absorption system. Exposed pastes and mortars with fly ash lose more water than those without fly ash and pastes lose more water than mortars. Water loss from specimens occurs for much a much longer time period than previously determined.