Temporal evolution of mesoscopic structure during hydration of cement

Author(s): S. Mazumder
Paper category: conference
Book title: Microstructural-related Durability of Cementitious Composites
Editor(s): Guang Ye, K. van Breugel, Wei Sun and Changwen Miao
Print ISBN: 978-2-35158-129-2
e-ISBN: 978-2-35158-123-0
Publisher: RILEM Publications SARL
Publication year: 2009
Pages: 140 - 149
Total Pages: 10
Language: English

Abstract: The temporal evolution of the mesoscopic (10⁰ - 10⁵nm.) structure while cement-water mixtures turn into gels of high compressive strength is central to present article. Recent small-angle neutron scattering based investigations exhibit temporal oscillations of mesoscopic structure. These oscillations are strongly dependent on the length scale of observation and on the medium of hydration (light or heavy water). While the formation of hydration products is synchronous for hydration with H2O, the process is nonsynchronous for hydration with D2O. The reason why morphological patterns of domains at different times look dissimilar, as seen before (Phys. Rev. Lett. 93 (2004) 255704; Phys. Rev. B. 72 (2005) 224208), for different hydration media emerges as a natural consequence of this finding. The structures arise from well-characterised chemical reactions as water diffuses through porous gel to bring about the water-surface interactions within the complex local geometry. The noteworthy observations point to the isotopic effect of hydrogen bonding on mesoscopic structure resulting from hydration although hydrogen bond with deuterium is only slightly stabler yielding a longer lifetime vis-a-vis bond involving hydrogen. These investigations are a step
forward towards general understanding of hydration process.

Online publication: 2012-05-16
Publication Type: full_text
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