• University of Tennessee researchers are investigating the long-term safety and durability of Reclaimed Asphalt Pavement (RAP) to determine if sustainable paving practices compromise road safety.
• The research focuses on understanding the frictional properties of RAP aggregates, particularly skid resistance, using mechanical and chemical methods to analyze aggregate composition and texture.
• Findings aim to guide transportation departments on the safe and effective use of RAP in road construction, balancing environmental benefits with safety considerations.

Researchers at the University of Tennessee are conducting research to determine the long-term safety and durability of Reclaimed Asphalt Pavement (RAP). This research addresses concerns about whether using RAP in road construction compromises safety, particularly regarding skid resistance under wet conditions. The study involves analyzing the frictional properties of RAP aggregates to provide insights for transportation departments to make informed decisions about RAP usage.

• What: Research into the safety and durability of Reclaimed Asphalt Pavement (RAP) and its impact on road safety, particularly skid resistance.
• Who: Jingtao Zhong and Baoshan Huang, civil engineering researchers at the University of Tennessee, Knoxville, in collaboration with the Tennessee Department of Transportation.
• When: Ongoing research, with funding received during the state project number RES2023-15.
• Where: Research conducted at the University of Tennessee, Knoxville, with implications for road construction and maintenance across the U.S.

The research addresses the critical question of whether the increasing use of RAP in road construction compromises safety. The focus on skid resistance is particularly important given the high percentage of weather-related accidents that occur on wet pavement. By analyzing the frictional properties of RAP aggregates, the researchers aim to provide data-driven insights that can help transportation departments make informed decisions about the safe and effective use of RAP, balancing environmental benefits with safety considerations. The two-step process involving mechanical and chemical extraction methods provides a comprehensive approach to understanding the composition and properties of RAP aggregates.

The University of Tennessee's research on RAP is crucial for ensuring that sustainable paving practices do not compromise road safety. By focusing on the frictional properties of RAP aggregates, the study aims to provide valuable insights for transportation departments to make informed decisions about RAP usage. The results of this research will likely influence future guidelines and standards for RAP implementation, balancing environmental benefits with the need for safe and durable road infrastructure. Further research and field testing will be necessary to validate these findings and assess the long-term performance of RAP in real-world conditions.