Evaluation of the Dynamic Late Lane Merge System at Freeway Construction Work Zones

In normal work zones with lane closures, drivers do not merge at any one definite point, thus causing sudden interruption in traffic flow and sometimes higher delay. The dynamic late lane merge system (DLLMS) was used to identify a definite merge point, improve the flow of the congested freeway work zones and reduce queue lengths in the freeway travel lanes. During the 2006 construction season, the DLLMS was implemented on three freeway segments in southern Michigan. Each work zone segment involved a lane closure from two to one lane. Based on the travel time characteristics, queue, merge locations, and throughput, the effectiveness of the DLLMS was evaluated by the Wayne State University Transportation Research Group. Before period data was not available, so a conventional work zone merge system located on EB I-94 was used as a control site for the WB I-94 test site. Since the two I-69 test sites are approximately 150 miles away from the EB I-94 control site, the I-94 control site could not be used as a control for the I-69 sites. When comparing the I-94 control and test sites, the presence of the DLLMS improved the flow of traffic and increased the percentage of merging vehicles that merged at the taper.