Stephen D. Cramer, University of Wisconsin, Madison
Barry Paye, Wisconsin DOT
Admixtures, Air content, Alternatives analysis, Concrete pavements, Durability, Fresh concrete, Service life, Test procedures, Wisconsin
A recent study sponsored by the Wisconsin Department of Transportation (WisDOT) has revealed that the air contents in fresh concrete measured by pressure meter method are lower than those in the hardened concrete of the same pavement concrete. In addition, observation of air entrainment in hardened concrete shows interconnected and irregular void patterns that could lead to a decrease in durability and pavement life. Determining accurate air contents on fresh concrete in the field will allow the WisDOT and paving industry to optimize properties of the concrete mix in regards to strength, durability, and economy. The objective of this research is to evaluate accuracy of test methods for measurement of air content in fresh concrete in comparison to air content in the hardened concrete of the same type, and to determine the hardened air content and air void dispersion in WisconsinÛªs concrete pavement. The results will recommend proper method and procedure to determine air content in fresh concrete on WisDOT projects, recommend values for concrete properties to be used by WisDOT in the Standard Specifications for Highway and Structure Construction and the applicable Standard Special Provisions, and to report potential changes in practice and benefits in terms of performance and cost savings.