期刊
CEMENT AND CONCRETE RESEARCH
卷 79, 期 -, 页码 31-44出版社
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.cemconres.2015.07.008
关键词
Ettringite; Metaettringite; Hydration states; Thermodynamic properties; Hysteresis
资金
- European Union Seventh Framework Programme (FP7) [264448]
The stability of ettringite as function of temperature and water vapour pressure was studied on synthetic samples using X-ray diffraction, thermogravimetric analysis, sorption balance measurements and different calorimetry techniques. Crystalline ettringite has a water content per mol of Al2O3, n, varying from 30 to 32 H2O, while the amorphous product formed on drying it, metaettringite, has only 9 to 13 H2O. Very large hysteresis was observed during the desorption and absorption cycles. The total enthalpy values associated with the decomposition and reformation of ettringite were consistent and similar. During rehydration, different absorption stages were identified and quantified with sorption calorimetry. Due to the hysteresis it was not possible to model the absorption/desorption behaviour using the enthalpies determined by calorimetiy, so the values calculated with the van't Hoff equation were used. The area of performance of ettringite-based systems recommended in this work has been extended compared to previously reported data. (C) 2015 Elsevier Ltd. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据