title: Concrete/mortar water phase transition studied by single-point MRI methods.
abstract: A series of magnetic resonance imaging (MRI) water density and T2* profiles in hardened concrete and mortar samples has been obtained during freezing conditions (-50 degrees C < T < 11 degrees C). The single-point ramped imaging with T1 enhancement (SPRITE) sequence is optimal for this study given the characteristic short relaxation times of water in this porous media (T2* < 200 microseconds and T1 < 3.6 ms). The frozen and evaporable water distribution was quantified through a position based study of the profile magnitude. Submillimetric resolution of proton-density and T2*-relaxation parameters as a function of temperature has been achieved.
authors.affiliation: Department of Physics, University of New Brunswick, Fredericton, Canada.
authors.forename: P J
authors.initials: PJ
authors.lastname: Prado
authors.forename: B J
authors.initials: BJ
authors.lastname: Balcom
authors.forename: S D
authors.initials: SD
authors.lastname: Beyea
authors.forename: R L
authors.initials: RL
authors.lastname: Armstrong
authors.forename: T W
authors.initials: TW
authors.lastname: Bremner
authors.forename: P E
authors.initials: PE
authors.lastname: Grattan-Bellew
mesh_terms: D002484:Cementation; D003252:Construction Materials; D005615:Freezing; D006801:Humans; D008279:Magnetic Resonance Imaging; D016062:Porosity; D014867:Water
chemical_list: D014867:Water