NTL Record

Title Air Void Analyzer (AVA)
Record ID 66179
Personal Name
Contributor
Crawford, G. I.; Correa, Angel; Distlehorst, Jennifer A.; Michel, Carin; McCrae, TaMara
Corporate Creator United States. Federal Highway Administration
Corporate
Contributor
Turner-Fairbank Highway Research Center
Publisher United States. Federal Highway Administration
Publication Date 20060101
Language English
Abstract Premature deterioration of cement-based concrete structures puts a tremendous financial burden on many transportation agencies. Moreover, badly deteriorated concrete in pavements, bridges, and other highway structures adversely affects economic productivity by increasing the number of work zones while indirectly placing motorists at risk. In much of the United States, concrete deteriorates as a result of repeated freezing and thawing. Damage often is exacerbated by multiple applications of deicing salts, which accelerate cracking, deterioration, and surface scaling. Concrete life can be increased by improving its ability to endure repeated freeze-thaw cycles over its expected design life. The presence of closely spaced air voids in concrete is commonly singled out as the primary factor in improving the freeze-thaw resistance of concrete. Researchers believe that as water expands during freezing, the pressure the water develops increases in relation to the distance it must travel to reach the nearest air void. Consequently, the more closely air voids in concrete are spaced, the less likely it is that the pressure of freezing water will damage the concrete. The air void analyzer (AVA) offers an efficient, real-time method for assessing the distribution of air voids in fresh concrete. The device can characterize the distribution of air voids in less than 30 minutes. With this information, adjustments can be made in the concrete batching process to ensure that air voids are spaced properly.
Rosap ID dot:40742
Rosap URL https://rosap.ntl.bts.gov/view/dot/40742
TRT Terms Analysis; Freeze thaw tests
Geographical
Coverage
United States
TRIS Online
Accession No
1153192
Report Number FHWA-HRT-06-057
Resource type Tech Report
URL https://ntlrepository.blob.core.windows.net/lib/66000/66100/66179/FHWA-HRT-06-057.pdf
Alternative URL https://www.fhwa.dot.gov/resourcecenter/teams/pavement/pave_1AVA.pdf
Format PDF
Database NTL Digital Repository