Effectiveness Evaluation of "Transverse Bar" Pavement Marking Pattern on the Reduction of Rear-End Collision Risk

A possible approach to reduce the risk of rear-end collisions is to change the behaviour of road users such that one allows sufficient spacing between his/her vehicle and the leading vehicle. In this pilot project, which implemented the "Transverse Bar" pavement marking pattern on Highway No. 35 (Rama II Road), the appropriate spacing between two cars was determined to be 47 meters. Three sets of transverse bars were painted on the pavement surface on the middle and median lanes of a five-kilometre segment along; appropriate warning signs were also installed. It was found that the "Transverse Bar" pavement marking pattern contributed to larger average spacing of vehicles. The effectiveness of such an approach nevertheless decreased over time. Furthermore, the "Transverse Bar" contributed to less rear-end collisions when analysis was performed at 99.39% confidence level.