751AIR-ENTRAINING ADMIXTURES

751 Page 504751 AIR-ENTRAINING ADMIXTURES

Air-entraining admixtures for concrete will be 100% vinsol resin based or one of the products as listed on the Department’s Approved Products List for air-entraining admixtures and will conform to the requirements of AASHTO M 154, except as modified below: Concrete having sufficient air-entraining admixture added to entrain 5 to 7% air will have compressive strength at the age of 7 days of not less than 90% of the standard. The standard will consist of a concrete of equal cement content, equal consistency, and of the same aggregates in adjusted proportions, but without the addition of an air-entraining admixture. 752 Page 505752 CHEMICAL ADMIXTURES FOR CONCRETE 752 CHEMICAL ADMIXTURES FOR CONCRETE The chemical admixtures used for concrete will conform to AASHTO M 194. Chemical admixtures for concrete will be a non-chloride-based material containing less than 1% chloride ion by weight of admixture. Viscosity modifying admixtures (VMA) may be used in self-consolidating concrete (SCC) to attain desired performance. The approval of the Department’s Concrete Engineer is required prior to use of any VMA. Chemical admixtures for dry cast concrete which are not classified in AASHTO M 194 or do not meet the requirements of Section 751 must be approved by the Department’s Concrete Engineer prior to use.