Manara - Qatar Research Repository
1-s2.0-S1369847821000243-main.pdf (1.58 MB)

Investigating the impact of a novel active gap metering signalization strategy on driver behavior at highway merging sections

Download (1.58 MB)
journal contribution
submitted on 2023-09-05, 06:53 and posted on 2023-09-19, 06:46 authored by Nora Reinolsmann, Wael Alhajyaseen, Tom Brijs, Ali Pirdavani, Qinaat Hussain, Kris Brijs

A safe headway to the lead vehicle is important to reduce conflicts with merging vehicles from highway on-ramps. Previous research has outlined the advantage of gap metering strategies to yield sufficient space to merging vehicles and improve highway capacity during peak hours. However, prevailing gap metering systems fail to indicate the minimum required gap and leave it to the drivers’ judgment to adjust their headway. This paper proposes a new Active Gap Metering (AGM) signalization that helps outer lane drivers to adjust their headway to the lead vehicle when approaching highway ramps with incoming vehicles. This AGM signalization represents a combination of pavement markings and an innovative Variable Message Sign (VMS). The AGM system was tested alone and in combination with additional variable speed limits (VSL) in distinct environments of the Doha Expressway in the State of Qatar using a driving simulator. The driving behavior of 64 drivers was analyzed using repeated-measures ANOVA. The results showed that the AGM effectively influenced the drivers’ behavior on the right stream lane. Drivers did gradually increase the distance to the lead vehicle, which resulted in optimal headways to merging on-ramp vehicles. Most importantly, the minimum time-to-collision (TTCmin) to the merging vehicle was increased by an additional 1–1.5 s as compared to no treatment. The proposed AGM signalization can, therefore, be considered by policymakers to influence drivers’ headways at critical merging sections.

Other Information

Published in: Transportation Research Part F: Traffic Psychology and Behaviour
See article on publisher's website:


Open Access funding provided by the Qatar National Library



  • English



Publication Year

  • 2021

License statement

This Item is licensed under the Creative Commons Attribution 4.0 International License

Institution affiliated with

  • Qatar University
  • College of Engineering - QU
  • Qatar Transportation and Traffic Safety Center - QU

Usage metrics

    Qatar University



    Ref. manager