The objective of this research was to determine if a relationship exists between crashes and right-turn lane design characteristics with specific consideration of the age of the driver. The research team used crash data of selected intersections in Texas for a six-year period (2009—2014) to perform this study. The types of right-turn lane design considered for analysis included shared lane with island, shared lane with island and dedicated downstream lane, right-turn lane with island, right-turn lane with island and dedicated downstream lane, and shared lane. An examination of the distribution of drivers by miles driven and by involvement in right-turn-related crashes showed that younger drivers were involved in more crashes despite driving less than older age groups. This could be representative of the inexperience or the likelihood of risk-taking behaviours of younger drivers. The characteristics that were examined included right-turn treatment type, presence of a dedicated departure lane, corner radius, and width of the channelized island. For most of the comparisons, the distribution of drivers by age showed similar patterns regardless of the type of right-turn treatment or other right-turn lane characteristic studied– younger drivers are having a disproportional number of crashes. The distribution of drivers by width of the channelized island (measured along the receiving roadway) did indicate that the widest channelized islands might be associated with more older-driver crashes. A larger sample size or a different study method, perhaps a before-after method, might be needed to verify this observation. A field investigation along with a safety before-after study could also illustrate whether older drivers have greater difficulties or compensate for the difficulties by positioning their vehicle differently on approaches or, perhaps, avoiding these intersections. (Author/publisher)
Samenvatting