Regional Microscopic Simulation Model for Studying Traffic Control Strategies at a Work Zone

Work zones have significant negative impacts resulting from reduced capacity and speed, and increased accidents and delay. Thus, it is important to design a traffic control strategy that has minimum potential impact on the traffic at the work zone and the traffic in its vicinity. In this study, a regional microscopic model is used to evaluate different control strategies at a work zone on interstate I-89 in Vermont. The strategies are, i) no lane closure, but no shoulders, ii) one northbound lane closure, iii) one northbound and one southbound lane closure. The model predicted no significant traffic jam at any place in the work zone and surrounding area. Evaluation of strategy ii) for three different speed limits of 45, 35, 25 mph also resulted in a smooth traffic flow, but at reduced speed and increased density. However, a significant diversion of traffic to alternate routes was predicted. Data gathered during construction field observation and data fairly agree with the model prediction. The during-construction and beforeconstruction analysis shows significant diversion of commuters on weekdays. But the traffic flow on a weekend during-construction is found similar to the flow on weekend before-construction.