Safety Impacts of Variable Speed Limits - A Simulation Study

Variable speed limits have great potential for smoothing traffic and increasing traffic safety. In this study, safety impacts of variable speed limits applications on motorways have been assessed by using microscopic simulation. The main factors considered include range of speed limits, penetration rates, and enforcement levels. The study results show that application of variable speed limits on motorways can significantly reduce speed differences between and within lanes and number of small headways, an indication of safety benefits to drivers. This is part of European COOPERS project which aims to develop cooperative vehicle-infrastructure systems for increasing road safety.