Abstract

Although a proven safety concept, often used at racing circuits and mountain regions for stopping heavy goods vehicles (HGV) in case of brake-system failures, arrester beds are becoming an attractive safety measure at motorway exit ramps. Their advantage over the classical design, which includes road safety barriers and crash cushions, is that arrester beds are using the large unused area behind the exit ramps of motorways which maximizes the stopping time and reduces the Accident Severity Index (ASI) of the errant vehicles. The motorway exit ramps are one of the most critical safety points due to high-speed reduction, delayed driver reactions and possible interactions with other users. This provides an opportunity for the development of new design concepts that would increase road safety by reducing accident rate or at least mitigate the consequences, which includes passenger injuries, secondary collisions, road closures and material damage. This paper presents the results of an experimental and numerical study performed to evaluate the effectiveness of a gravel-filled arrester bed at safely stopping errant vehicles on motorway exit ramps. The study was conducted during the testing period of the six testing gravel arrester beds built in Slovenia in 2018.