Observation of Water Transport in Cement-based Materials by Neutron Radiography and Service Life of Reinforced Concrete Structures

Author(s): Folker H. Wittmann, Peng Zhang and Tiejun Zhao
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: 115-122
Total Pages : 8
Language : English

Abstract: Cement-based materials have a complex composite and porous structure. Durability of this type of materials depends strongly on movement of water and ions dissolved in water in the pore space. Neutron radiography is a non-destructive method to determine water movement in concrete quantitatively and with sufficient spatial resolution. The potential of this method for fundamental concrete research shall be presented and discussed by means of selected examples in this contribution.
Water absorption by capillary action can be visualized and quantified. Influences of surface treatment with water repellent agents and of an applied stress can be studied. In the same way the long-lasting drying process of concrete can be followed in detail. Of particular interest is the penetration of water or aqueous salt solutions into the pore space and into cracks. Results as obtained on concrete without load and under compressive or tensile stress shall be presented. The efficiency of self-healing of cracks can also be studied. In the same way interesting results can be obtained on other cement-based materials such as SHCC. The influence of freeze-thaw cycles on penetration of water has also been investigated.
It will be shown that neutron radiography is a powerful method to study deteriorating processes and the influence of protective measures in concrete in detail. Results of neutron radiography will finally contribute to a better understanding of water movement of concrete and at the same time it will help us to find ways to improve durability and service life of concrete in practice. Service life design can become more reliable and more realistic.

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