Abstract
Driving assistance system application and road infrastructure redesign offer
two different options to improve traffic safety, with however quite different nature and
scenarios for implementation. This paper provides an approach for a structured, comparative
evaluation of long-term strategies for these two options, with a focus on possible substitution
of infrastructure by in-vehicle systems (IVS). The purpose is to support decision making,
taking into account both safety performance of measures for individual road network
elements (micro level) and an overall evaluation of alternative strategies for a complete part
of the road network (macro level). We develop a model to facilitate estimation of relative
safety effects for both IVS application and infrastructure redesign, which then allows
estimating absolute safety effects for IVS measures. The essence of this model is a break-down
of road traffic safety in the underlying components accident probability and accident
consequence, and identification of five speed and conflict related variables that influence
these components, and are influenced by traffic safety measures. For synthesis of the detailed
results to a decision support outcome, a normalisation based evaluation method - grey
relational analysis (GRA) - is applied. The application of the bi-level (micro and macro)
approach is illustrated.
Keywords - traffic safety, comparative analysis, causal chain, grey relational analysis, driving assistance systems, infrastructure measures