Studies on Compatibility between Slipform Paving Cement Concrete and Complex Admixtures

Abstract

The slipform paving technique has been utilized widely in the construction of high-class highway cement concrete pavements in China, resulting in increased use of complex admixtures. Complex admixtures usually contain various components that may have potential compatibility issues, not only between admixtures and cement, but also between admixture components. In order to alleviate or eliminate potential incompatibility problems, it is necessary to adjust the mix proportions and admixture chemical components by taking into account the real-life materials and surrounding conditions. An optimum dosage of the complex admixture should be determined according to the specific job requirements and construction technique. Compatibility issues always arise between admixtures and cements. It was found that Na2 S O4 and Ca Cl2 may increase the early strength, but also may reduce the slump of the mix. When the resin-based air-entraining agent and water reducers were used together, they produced a large amount of resid...