The Admixture Systems business of BASF’s North American Construction Chemicals divisionhas announced a new technology for freeze-thaw durability that eliminates the need for air-entrained concrete. This patent-pending, microsphere-based admixture and point-of-use manufacturing system is being developed to help concrete professionals overcome the challenges traditionally associated with the variability and uncertainty of producing air-entrained concrete.
Microspheres are extremely small, hollow spheres that have a highly resilient, tough, but flexible, polymeric shell. Similar to entrained air, they provide stress relief zones for the expansion of freezing water within concrete, enhancing its long-term durability. Microspheres are not susceptible to variations in ambient conditions, concreting materials, construction practices and other factors that often impact the air void system in concrete. The compressive strength of concrete treated with the microsphere-based admixture technology can be over 30 percent higher than an air-entrained concrete, because of the difference in air content.
BASF plans to commercialize the microsphere-based admixture technology in 2015.