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ASR Reference Center

Welcome to the ASR Reference Center! This Reference Center was developed to provide users with access to pertinent information related to alkali-silica reactivity (ASR). The Reference Center has been organized for quick and easy access to various resources, and will be updated regularly to ensure that the most up-to-date information is available. Information that can be found on the Reference Center includes research reports, guidance documents, specifications related to ASR, field trials reports, and helpful links.

Alkali-silica reaction (ASR) is a materials related distress that has resulted in the premature deterioration of concrete structures throughout the world, including bridges, dams, and pavements. ASR is caused by the reaction between alkali hydroxyl ions in portland cement and certain siliceous minerals found in some aggregates. When moisture is introduced, the product of this reaction is a gel that surrounds the aggregate within the concrete matrix. The gel expands and often leads to significant expansion and cracking, leading to a reduction in the service life of the structure.

Do you have some information that you would like to see on the Reference Center? Email Gina Ahlstrom at

Updated: 01/08/2013