This study investigated the effect of an alternative
merge sign configuration within a freeway work zone. In this alternative configuration,
the graphical lane closed sign from the MUTCD was compared with a MERGE/arrow
sign on one side and a RIGHT LANE CLOSED sign on the other side. The study
measured driver behavior characteristics including speeds and open lane
occupancies. The measurements were taken at two identical work zones on I-70 in
Missouri, one with the new test sign and the other with the standard MUTCD
sign. The study found that the open lane occupancy upstream of the merge sign
was higher for the test sign in comparison to the MUTCD sign. Occupancy values
at different distances between the merge sign and the taper were similar for
both signs. The test sign had 11% more traffic in the open lane upstream of the
merge sign. In terms of safety, it is desirable for vehicles to occupy the open
lane as far upstream from the taper as possible to avoid conflicts due to the
lane drop. Thus, the test sign proved to be a good alternative to the MUTCD
sign.
Title: Investigation of Alternative Work Zone Merging Sign Configurations
Published: July 2014
Report number: cmr14-018
Project number: TRyy1318
Author(s): Praveen Edara, Carlos Sun, and Zhongyuan (Eric) Zhu
Performing organization: Department of Civil Engineering, University of Missouri-Columbia
