Durability of concrete against weak sulfuric acid in soil

Title: Durability of concrete against weak sulfuric acid in soil
Author(s): Tomoyuki Koyama, Yasunori Matsufuji, Shizuo Harada, Toshio Yonezawa, Kyoichi Tanaka, Etsutaka Maeda, Fumio Oshida
Paper category : conference
Book title: 2nd International Symposium on Service Life Design for Infrastructures
Editor(s): K. van Breugel, Guang Ye, Yong Yuan
Print-ISBN: 978-2-35158-096-7
e-ISBN: 978-2-35158-097-4
Publisher: RILEM Publications SARL
Publication year: 2010
Pages: 213 - 220
Total Pages: 8
Nb references: 14
Language: English

Abstract: There are many concrete buildings placed in relatively weak, low-density sulfuric acid soil with a pH of 4 to 5. In this study, the long term exposure test has been performed at a hot springs area in order to clarify the durability of concrete under these environments. The degradation process and durability were discussed regarding the physical/chemical aspects and microstructures of various concrete specimens. As the results of 15 years exposure, the deterioration of the concrete in weak sulfuric acid soil was only few mm from the surface, and inside the concrete appeared to not have deteriorated at all at first glance. However, S elements invaded inside of the non-neutralized area that looked sound and enttringite was formed. The formation of ettringite temporarily densified the microstructure of cement hydrates and decreased the invasion rate of S. Then with the increase of ettringite, the microstructure started to ruin caused by the expansion due to the formation of it. Finally, S elements couldn’t be observed on the surface. From these results and literatures, this paper presented proposals regarding the deterioration processes of concrete in weak sulfuric acid soil.

Online publication: 2011-04-20
Publication type : full_text
Public price (Euros): 0.00