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International Conference on Alkali Aggregate Reaction in Concrete (ICAAR)

Alkali-aggregate reaction has been studied since the mid 1930s after the discovery of alkali-silica reaction (ASR) by Thomas Stanton of the California Division of Highways. A conference series devoted to understanding reaction mechanisms, testing methods, prediction, diagnosis and repair has been active since 1974 with a total of 15 conferences. The next conference is scheduled for 2021 in Lisbon.

This website is an online consolidation of all ICAAR Conference Proceedings made available in electronic format.

So, what is Alkali-Aggregate Reaction?

Alkali-aggregate reaction (AAR) is an overarching term for two types of premature concrete deterioration: alkali-silica reaction (most common) and alkali-carbonate reaction (less common). These forms of deterioration involve a chemical reaction between CERTAIN aggregate types and the internal pore solution in concrete. The chemical composition of the cementitious materials (main) and the aggregates (to a lesser extent) dictate the composition of the pore solution and thus the aggregate reactivity. In the presence of moisture this reaction may result in deleterious expansion and cracking and can ultimately limit the service-life of the affected concrete.

Website Maintenance

The website is currently maintained by Dr. Jason H. Ideker who is a recognized expert in AAR test methods, mitigation and diagnosis and prognosis of field structures undergoing alkali-silica reaction. He is a Professor at Oregon State University. He can be contacted at: [email protected].