HANOVER, N.H. --
Pavements and Materials
The Pavements and Materials section of the Engineering Resources Branch (ERB) at the Cold Regions Research and Engineering Laboratory (CRREL) in Hanover, New Hampshire, combat the damaging effects of concrete frost heaving and thaw settlement, and develop novel pavements and materials for military engineering, combat construction, and civil works infrastructure applications for the Army, Air Force, and regional Department of Transportation (DOT) organizations.
The team validates long-term durability of cold weather admixture systems (CWAS) and proves comparable or improved performance vs. control concrete in both summer and winter months. When placing concrete in cold weather, it is possible to employ off-the-shelf additives as the sole method of freeze protection, in lieu of more traditional techniques such as heated temporary enclosures or heated curing blankets.
Research and development of CWAS has been a focus since the late 1980s.
In the last several decades, CWAS was demonstrated to be less costly and labor intensive than traditional cold weather concrete techniques, and several field demonstrations placed in the late 1990s and early 2000s remain in service today. Adoption of these methods in civil industry has been minimal, however, likely due to a lack of performance based guidance, as well as a perceived risk of early setting associated with the very high recommended quantity of admixture.
Status
Laboratory testing is underway In support of long term durability validation, the team has traveled to multiple field sites to collect samples and assess the condition of in-service concrete. These sites exist in locations throughout New England, as well as Alaska and Michigan. The team has also placed specimens at the U.S. Army Corps of Engineers (USACE) natural exposure site in Treat Island, Maine. The team also investigates the long-term durability of cold weather concrete, and has recently completed the analyses to quantify and predict long-term durability vs. conventional concrete methods (winter, summer emplacements).