Re-Evaluating the Risk of Using Higher-Skid-Resistance Aggregates

Abstract

Aggregate with higher skid resistance is used in many countries around the world to improve road safety. It has been tested for skid resistance in the laboratory and measured in service for many years. Certain rock types and asphalt mixes offer more skid resistance. The laboratory test methods have not changed for many years. Road surfaces achieve a state of in-service equilibrium depending on many factors, and roads are now experiencing additional changes due to issues ranging from greater use of electric vehicles to climate change in its many forms. This paper considers whether the previous methods are still able to offer reliable prediction. The paper re-evaluates research performed in the period 1990 to 2010 to consider whether the testing of road surface aggregate needs to be updated for the early 21st century. The authors believe this paper is significant for all countries to optimize the performance of their road networks in line with changes in service conditions.

Keywords

• re-evaluation
• aggregate
• skid resistance
• performance