Citation

Kraan M, van der Zijpp N, Tutert B, Vonk T, van Megen D. Transp. Res. Rec. 1999; 1689: 60-67.

Copyright

(Copyright © 1999, Transportation Research Board, National Research Council, National Academy of Sciences USA, Publisher SAGE Publishing)

DOI

10.3141/1689-09

PMID

unavailable

Abstract

The use of variable message signs (VMSs) is generally considered to be a powerful tool to influence route choice so as to increase safety and comfort during driving and improve network performance and to make optimum use of available capacity. Assessing whether such effects actually occur when VMSs are installed is a difficult task. This paper summarizes an extensive evaluation study carried out on the installation of 14 new VMSs on the Amsterdam orbital motorway. The study involves a number of issues. First, a networkwide analysis of aggregate performance indicators, such as traffic performance, severity of congestion, and travel time delay, is included. Second, the relation between the messages displayed on the VMS and the travel times experienced by drivers is analyzed. Finally, a stimulus-response analysis to find out how drivers actually respond to the messages is described. The study showed that the use of VMSs has a positive impact on network performance in the Amsterdam freeway system. Total congestion has decreased, and traffic performance has increased. Variation in congestion has decreased as well as variation in average travel speed. This finding implies that travel time has become more reliable and that the traffic flow is more homogeneous. The technical assessment showed that the displayed queue lengths, if interpreted correctly by drivers, are a good measure for expected delay. User response analysis showed that information has a significant effect on route choice. In general, the VMSs were found to improve the efficiency and reliability of the freeway system.

Language: en