01506662

Component

In the Highway Capacity Manual, a variety of factors were considered to enhance the accuracy of capacity estimation under prevailing conditions. However, no factors accounted for the possible changes of capacity due to novice drivers were provided. The primary objective of this study was to develop adjustment factors to evaluate the impacts of novice drivers on capacity of basic roadway segment. On-road experiments were conducted for measuring the car-following behavioral data associated with novice and experienced drivers. Comparative analyses were conducted to compare the spacings and headways selected by novice and experienced drivers as they were following other vehicles. It was found that novice drivers prefer maintaining relatively larger spacings and headways than experienced drivers do. These differences in spacings and headways were statistically significant. Linear regression analyses were then conducted to relate the vehicle speeds to the spacings and the headways for novice and experienced drivers. Combined with the fundamental relationships between these two car-following behavior measures and traffic flow parameters, adjustment factors were developed to quantitatively evaluate the effects of novice drivers¡¯ car-following behaviors on capacity of basic roadway segment. It was found that the reduction in capacity increases with an increase in the proportion of novice drivers in the traffic stream. The presence of novice drivers may result in up to 13% of capacity reduction when novice drivers travel on the whole road with the average speed of 90 km/h. The validity of implementing the novice driver adjustment factor was tested against measured data. The results of validation determine that the proposed adjustment factors result in improved estimates of capacity of basic roadway segment.

This paper was sponsored by TRB committee AHB40 Highway Capacity and Quality of Service.

01503729

14-3343

English

19p

2014

Transportation Research Board 93rd Annual Meeting

Digital/other

Photos; References (16) ; Tables

Automobile drivers; Behavior; Car following; Driver experience; Headways; Highway capacity; Novices; Recently qualified drivers; Traffic flow; Traffic volume

Highways; Operations and Traffic Management; Safety and Human Factors; I73: Traffic Control; I83: Accidents and the Human Factor

Transportation Research Board Annual Meeting 2014 Paper #14-3343

TRIS, TRB, ATRI

Jan 27 2014 3:09PM