Passing demand on lower volume two-lane highways

During a pavement resurfacing project a two-lane highway generally remains in service to traffic. Immediate application of no-passing zone markings is expensive and usually results in the need for re-application of the markings within a few days. The lack of no-passing zone markings could produce a hazard to the driving public. The objectives of this study were to evaluate potential safety problems and to recommend traffic volumes at which there is a significant hazard associated with the absence of no-passing markings during a resurfacing project. Analytical models developed by Glennon and Wardrop and the ROADSIM simulation model were used to predict flow characteristics. The operational characteristics associated with levels-of-service were examined to aid the description of speed, passing frequency, passing capacity, platooning and delay.