Non-destructive measurements of 1H, 23Na and 35Cl profiles in building materials with NMR

Author(s): L. Pel, P.A.J. Donkers
Paper category: Proceedings
Book title: Proceedings on International RILEM Conference on Materials, Systems and Structures in Civil Engineering Conference segment on Moisture in Materials and Structures
Editor(s): Kurt Kielsgaard Hansen, Carsten Rode and Lars-Olof Nilsson
ISBN: 978-2-35158-178-0
e-ISBN: 978-2-35158-179-7
Publisher: RILEM Publications SARL
Publication year: 2016
Pages: 266 - 273
Total Pages: 8
Language : English

Abstract: It is widely acknowledged that chloride-induced corrosion is one of the main degradation mechanisms in civil structures based on reinforced concrete. Insight into the coupled moisture and ion transport phenomena can improve the assessment of durability aspects of existing structures. At the moment there is lack of experimental data on this topic that can be used to validate or discredit the wide range of models available in literature.
Nowadays there is a wide range of non-destructive techniques available. While most of these methods are able to detect chloride content non-destructively, none of them is able to measure combined moisture and ion transport simultaneously. Using a specially designed Nuclear Magnetic Resonance (NMR) setup quasi-simultaneously the 1H, 23Na and 35Cl content can be measured in building materials. As the gyromagnetic ratio of the selected nuclei are too far apart to be combined into one insert we have opted to use the main field of a 1.5 T whole body MRI system. The sensitivity of the current setup is sufficient to monitor the intrusion of seawater in cementitious materials. The relaxation of 1H, 23Na and 35Cl can be used to obtain pore-size information, and thereby information on the pore-ion concentration distribution during transport.

Online publication : 2016
Publication type : full_text
Public price (Euros) : 0.00