Evaluation of the long-term performance and life cycle costs of GTR asphalt pavements

• Pavements with terminal blend GTR modified mixes had similar to polymer modified sections.
• Core samples obtained GTR sections had similar fatigue cracking resistance to those obtained from polymer sections.
• The GTR modified sections had slightly higher life cycle costs.

This paper presents the results of a study that was conducted to evaluate the long-term field performance and life cycle costs of pavement sections constructed with terminal blend ground tire rubber (GTR) modified mixtures and compare it to those constructed using styrene–butadiene–styrene (SBS) polymer modified mixes. To this end, GTR and polymer modified pavement sections with varying traffic conditions were periodically evaluated during the first 2.5, 6, 8, and 10 years of service. In addition, different laboratory tests were conducted on core samples that were obtained from these sections to examine their resistance to fatigue and low-temperature cracking as well as to moisture induced damage. The field evaluation of pavement sections constructed with GTR modified mixes showed good performance after 10 years of service, which was similar to that obtained for sections where polymer modified mixes were used. The core samples from GTR modified sections had similar fatigue cracking resistance to those obtained from polymer modified sections, but slightly better resistance to low temperature cracking and moisture induced damage. Finally, the sections with GTR modified mixture had slightly higher life cycle costs that those constructed with polymer modified mixes. This was attributed to the higher initial cost of GTR asphalt mixtures used in these sections.