Improving Freeze-Thaw and Deicer Damage Resistance of High Early Strength Concrete Mixtures Using AASHTO R 101 Concepts

Abstract

High early strength (HES) concrete mixtures are widely used for partial- and full-depth repairs of concrete pavements. HES concrete mixtures are typically required to meet pavement re-opening strengths in times ranging between 6 and 24 hours after mixing. To achieve such high early age strengths, HES mixtures are designed with very high cement contents, high accelerator and water reducer dosages, and low water-to-cement ratios. These design choices often led to poor long-term durability of the repaired sections, causing premature failures and forcing new repair operations on the same pavement sections. A leading cause of premature failures reported in the available literature is the poor freeze-thaw performance of HES mixtures often caused by faulty air systems, susceptibility to deicer-related damage, and high fluid penetrability. This study offers some insights on how to improve long-term freeze-thaw and deicer-related damage resistance of HES mixtures. To do so, concepts obtained from the performance engineered mixtures (PEM) document AASHTO R101 are implemented. These concepts include the use of formation factor and other electrical-based tests to characterize the transport-related properties of HES concrete mixtures. The results from the performed tests are then used to predict the service life of the repair section using available durability-based service life models. The results show that applying PEM concepts to HES concretes can help improve HES mixture resistance to freeze-thaw and deicers damage while still ensuring adequate early age mechanical performance.