Improving Durability of Asphalt Pavements in Louisiana through Increased In-Place Field Density. Issue 10 (October 2020)

• Record Type: Journal Article
• Authors: Akentuna, Moses; Mohammad, Louay N.; Kim, Minkyum; Cooper, Samuel B.; Cooper, Samuel B.
• Is Part Of: Transportation research record. Volume 2674:Issue 10(2020)
• Page Start: 806
• Page End: 816
• Publication Date: 2020-10
• Subjects: Transportation -- Periodicals; Roads; Transport -- Périodiques; Routes -- Périodiques; Routes -- Conception et construction -- Périodiques; Roads; Transportation; 388.05
• DOI: 10.1177/0361198120940685
• Languages: English
• ISSNs: 0361-1981

Abstract

The objective of this project was to evaluate the effects of increasing the initial in-place density of asphalt pavements on expected field performance and durability. This study was completed as part of the FHWA's demonstration project on "Enhanced Durability through Increased In-Place Pavement Density." Two approaches for increasing in-place density were explored: (i) the addition of an Evotherm warm-mix asphalt (WMA) additive at a dosage rate of 0.6% by the weight of mix; and (ii) the addition of 0.2% asphalt binder (Plus AC) to the design optimum asphalt binder content of standard dense-graded mixtures. The field component of the research involved three 4, 000-ft long test sections representing control hot-mix asphalt (HMA) mixtures, Evotherm WMA mixtures, and the Plus AC HMA mixtures. Each test section included a binder and a wearing course for a total of six mixtures. Density measurements were determined in the laboratory from field cores taken at each test section. The high- and intermediate-temperature properties of field cores were evaluated using the Loaded Wheel Tracking and Semi-Circular Bending tests, respectively. Further, the Indirect Tensile Dynamic Modulus (IDT |E*|) test was conducted for full viscoelastic characterization of the asphalt mixtures. The two approaches considered in this study were successful in increasing field density, especially for the binder course mixtures. The two strategies for increasing in-place density also resulted in better than expected resistance to cracking and rutting, as well as an increase in mixture stiffness as measured by the IDT |E*|.