کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1455951 | 1509735 | 2016 | 14 صفحه PDF | دانلود رایگان |
NMR relaxometry (Muller et al., 2012, 2013) quantifies the mass fractions of differently bound water in cement paste, as functions of hydration degree and water-to-cement ratio. We here reduce these findings to a single explanation: the density of C-S-H gel is solely governed by the specific precipitation space, across three “hydration regimes”: In regime I, solid C-S-H platelets (without gel porosity) precipitate on clinker surfaces. In regime II, C-S-H starts to include gel porosity. The forming gel densifies linearly with decreasing precipitation space. Thereby, regime III starts once the C-S-H gel has completely filled the capillary porosity. These findings allow for developing an analytical hydration model. It provides expressions for C-S-H gel densification and for the evolution of the volume fractions of clinker, of solid hydrates, as well as of the gel and capillary porosities, as functions of the water-to-cement ratio and the hydration degree; consistently representing published experimental data.
Journal: Cement and Concrete Research - Volume 88, October 2016, Pages 170–183