Study on Water Transport in Cement-based Materials by X-ray CT

Author(s): Lin Yang, Guojian Liu and Yunsheng Zhang
Paper category: Proceedings
Book title: 3rd International RILEM Conference on Microstructure Related Durability of Cementitious Composites
Editor(s): Changwen Miao, Wei Sun, Jiaping Liu, Huisu Chen, Guang Ye and Klaas van Breugel
Print-ISBN: 978-2-35158-188-9
e-ISBN: 978-2-35158-189-6
Publisher: RILEM Publications SARL
Publication year: 2016
Pages: 306-313
Total Pages : 8
Language : English

Abstract: For cement-based materials, water generally takes part in every form of the deterioration processes, which is the direct participant in much physical deteriorations and indirect participant in chemical deteriorations as a vehicle for transport of aggressive ions. A good understanding of water transport in cement-based materials is very important to assess the performance of materials, predict ion transport and develop service life models and durabilitybased design codes. In this study, X-ray computed tomography (X-ray CT) was applied to the investigation of water transport in cement-based materials. To enhance the X-ray attenuation of water in the CT image, CsCl was added to the water before absorption. Water transport in paste, mortar and concrete with same water to cement ratio were mainly focused in this study.
The results showed that the contrast of water in CT image was obviously improved by adding CsCl to the water. The evolution of water ingress into paste, mortar and concrete were continuously monitored by X-ray CT technique and the processes were shown in CT images.
The quantitative relationships between water uptake height (h) and exposed time (t) were also established in this paper, h=k×t1/2; and the value of k for paste, mortar and concrete were 2.83×10-4m/s1/2, 1.65×10-4m/s1/2 and 1.47×10-4m/s1/2, respectively. This work also illustrated that X-ray CT combined with CsCl enhancing was a powerful and reliable tool for the visualization of fluid transport in cement-based materials.

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