Deterioration of Concrete Immersed in Sulfuric Acid for a Long Term

Abstract:

Deterioration of concrete caused by sulfuric acid attacks in sewage and waste water treatment plants has been investigated. To evaluate this type of deterioration, concrete specimens immersed in sulfuric acid solutions are usually examined, and the mass loss and erosion depth of the specimens can be used as physical indicators of the degree of the deterioration, while the sulfate ion penetration can be used as a chemical indicator. Although an actual deterioration is progressing with time, most of previous experimental studies were carried out for a comparatively short time. There is a possibility, therefore, that the deterioration in practice has not been estimated completely yet based on the above indicators. The present study aims at investigating the changes in pore structures and chemical compositions of concrete specimens to evaluate long-term deterioration experimentally. Concrete specimens in which a part of cement was replaced with blast furnace slag, fly ash and silica fume were immersed in sulfuric acid solutions at 0.09 mol/L and 0.006 mol/L for around 1500 days. Pore structures in concrete were investigated to understand the relationship between the erosion depth and the internal space available for expansion due to gypsum production. In addition, chemical compositions of mortar in concrete were analyzed to know the effects of mineral admixture on the resistance to the deterioration.

• Periodical: Key Engineering Materials (Volume 711)
• Pages: 659-664
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.711.659
• Online since: September 2016
• Authors: Keisuke Tsubone, Yoshiki Yamaguchi, Yuko Ogawa, Kenji Kawai*
• Keywords: Long Term Deterioration, Mineral Admixture, Sulfuric Acid

References

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