This paper proposes the use of a driver population adjustment factor that considers the influence of driver behavior on traffic flow and capacity when drivers encounter and respond to changing roadway conditions found in work zones. The adjustment factor could be considered for use in the current work zone capacity equation in the Highway Capacity Manual. This factor is developed based on the concepts of driver familiarity, driver adaptability, driver aggressiveness, and driver accommodation. The development of this factor and these concepts are a product of several years of theoretical and field-based traffic flow and human factors research conducted by the authors. The overall principle embodied in the adjustment factor and the concepts is the tendency for drivers to adjust to changing roadway conditions while interacting with other drivers on the roadway. The degree of success in the adjustment to the conditions will determine the degradation or improvement in traffic flow from current Highway Capacity Manual work zone capacity equations. The adjustment factors presented in this paper have the potential to aid transportation professionals in estimating the capacity of a freeway work zone and ultimately in designing work zone strategies.
Samenvatting