| Popis: |
Degradation due to cyclic freezing and thawing is a major durability problem in the concrete industry. Since the early 1930s, air entrainment by surfactant chemistry has been used to improve the resistance to freezing and thawing of concrete. Despite its effectiveness, air entrainment is one of the most resource-demanding aspects of concrete production from a quality control perspective, particularly in ready mixed concrete. The focus of this study is a new microsphere-based admixture that has been developed to provide freezing-and-thawing protection of cementitious materials under cyclic conditions. This new technology is significantly different from current conventional surfactant-based chemistries and, consequently, it addresses and eliminates the typical issues associated with the traditional method of air entrainment. The paper will explain the mode of action of the new microsphere-based admixture that provides freezing-and thawing protection of concrete. |
