Field Condition Evaluation of Pavement with Dry Process Ground Tire Rubber (GTR) in Oklahoma

Abstract

Due to the high demand for vehicles in the increasing middle class, the massive crap tires have been an environmental issue. Ground tire rubber (GTR), that is produced from crap tires and used in pavement construction, has proven to be a primary method to get rid of the piles of tire landfills. Although asphalt pavement using dry process demonstrates less popularity than wet process, some recent studies have shown successful experience with dry process GTR mixes. To promote the successful use of GTR in Oklahoma, the Oklahoma Department of Transportation (ODOT) constructed a GTR test section on State Highway 33 (SH-33) for further identifying the benefit of dry process GTR. From March 2019 to July 2021, six field data collections were performed at intervals of pre-placement, post-placement, three months, nine months, one year, and two years. In each data collection, pavement cracking and rutting were evaluated via the Pave3D 8K system, pavement macro-texture and roughness were assessed via the Ames profiler, and pavement friction was collected via the grip tester. It is demonstrated that the GTR site exhibits comparable performance to that of the abutting warm mix asphalt (WMA) section in terms of rutting, roughness, texture, and friction, while with lower field cracking resistance.