Evaluating Variable Speed Limits and Dynamic Lane Merging Systems in Work Zones: A Simulation Study

Abstract

ITS technologies such as dynamic lane merging (DLM) and variable speed limits (VSL) have been deployed in roadway work zones in an attempt to enhance safety and mobility through vehicular traffic. The DLM system in its two main forms namely the early merge and the late merge was designed to advise drivers on definite merging locations whereas VSL were introduced to work zones to decrease speed fluctuations, variances, and to smoothen traffic through work zones. Up to date, there are no studies that contrast Maintenance Of Traffic (MOTs) plans including a combination of ITS technologies to standard work zones MOTs under matching work zone settings. This study simulates a two-to-one work zone lane closure configuration in VISSIM under six different MOT plans and compares work zone throughputs and travel times across MOTs namely Motorist Awareness System (MAS), early DLM, late DLM, VSL combined with MAS, a VSL and early DLM combination, and a VSL late DLM combination. Results showed that the combination of VSL and DLM or standalone DLM improve work zone throughputs and travel times compared to work zones with conventional static Florida MOT and work zones with VSL.