Effects of Alkali Migration through Water Retaining Structures
The phenomenon of alkali migration through concrete structures in service is largely unknown at this time. With
the number of concrete structures in the USBR inventory, a number of structures may be vulnerable to the effects
of alkali migration. How has alkali migration effected our structures and what is/has been the effect to durability
and service life?
Need and Benefit
USBR needs to understand this phenomenon in order to construct more resilient structures in the future as well
as develop a plan for mitigating potential damage throughout the existing inventory. Structures that were built
with quality materials are now showing damage from Alkali Silica Reaction when pre-construction testing
indicated that the risk for ASR was low. This build up of alkalies at the structure surface happens over years but a
viable structure can become at risk due to the migration, reducing the service life of the structure. We have
examples of this in our inventory but we do not fully understand the mechanism that causes the release of
alkalies or threshold values of alkalies that need to be present in order to begin damage. All of our structures leak
so the migration of alkalies is inevitable. How do we reduce the potential for damage?
Contact the Principal Investigator for information about partners.
Bureau of Reclamation Review
The following documents were reviewed by experts in fields relating to this project's study and findings. The results were determined to be achieved using valid means.
Effects of Alkali Migration through Water Retaining Structures (final, PDF,
By Jeffery Keim
Publication completed on September 30, 2016