Performance of Ground Tire Rubber Modified Asphalt Mixture Overlays over Jointed Concrete Pavements

State transportation agencies are trying various treatment methods available to delay or to prevent reflection cracking in rehabilitated pavements. Treatments that are used to reduce or prevent reflective cracking include use of binder modification such as asphalt mix with highly modified polymer binder or use of asphalt rubber modified mix. VDOT is planning to use ground tire rubber (GTR) modified asphalt mix (GTR SM12.5 E) on US 60, Richmond district as part of this research project. This will be the first use of GTR-SM 12.5 mix in Virginia using dry process method. This project also has ¾” Thin Hot Mix Asphalt Concrete (THMACO) layer as interlayer below GTR SM 12.5 E mix. Researchers will monitor the construction closely and collect information to document construction challenges and lessons learned. Asphalt samples will also be collected (both THAMACO and GTR SM 12.5) to characterize using different performance tests. A visual distress survey will be conducted during two year duration of this project at six months intervals unless any premature distress is observed.