1. Home
  2. RIP
  3. View Record
https://www.nationalacademies.org/trb/events

The Use of Recycled Plastic in Asphalt Pavements - Phase II

The Nebraska Department of Transportation (NDOT) is exploring sustainable alternatives for roadway construction. Among these, recycled plastics represent a particularly promising pathway, as both the United States and Nebraska face pressing environmental challenges, with more than 75% of waste plastics currently landfilled. In 2023, NDOT partnered with the University of Nebraska–Lincoln (UNL) asphalt research team to launch the first Nebraska feasibility project on this topic, "The Use of Recycled Plastic in Asphalt Pavements: Feasibility Study". Initial findings from Phase 1 demonstrated that, when melted and potentially coating the aggregates, the WP can improve both rutting and moisture damage resistance to a greater extent compared to solid (not melted) WP particles within the mixture. The Phase 1 project could demonstrate the feasibility of producing plastic-modified reclaimed asphalt pavement (RAP) recycled asphalt mixtures (NDOT SPR) mixtures in actual asphalt plants, leading to the construction of the first Nebraska plastic road in South Sioux City (SSC), in collaboration with South Sioux City administration and funding support from the Nebraska Environmental Trust. Based on initial findings of the NDOT funded research, 1% low-density polyethylene (LDPE) dosage (by aggregate mass) was selected for the SSC project. Despite these successes, the feasibility work was limited in scope. Laboratory-produced mixtures were not fully validated against the variability of plant production, long-term field performance remains unknown, and the recyclability of plastic-modified mixtures was not addressed. The findings of this research will demonstrate the feasibility of modifying asphaltic materials through the use of recycled plastics which can potentially improve the durability of asphalt pavements, resulting in significant cost savings and more sustainable asphalt pavements.