Advisory Committee Chair
Virginia P Sisiopiku
Advisory Committee Members
Robert W Peters
Date of Award
Degree Name by School
Master of Science in Civil Engineering (MSCE) School of Engineering
Work zones hinder mobility, affecting travelers and transportation agencies that are trying to ensure efficient traffic flow through work zones. A study by Wunderlich & Hardesty, 2002 reported that nearly 20% of the National Highway System roads have scheduled construction work during the peak construction season. Additionally, approximately 24% of non-recurring delays on freeways are caused by work zones. Given the time lost by travelers due to work zone induced traffic congestion, it is critically important to efficiently plan temporary traffic control (TTC) at work zones. However, earlier research conducted by Sisiopiku & Ramadan, 2017 confirms that the majority of State Departments of Transportation rely on their earlier experience without consideration of operational nor safety impacts. Earlier studies focused on analysis of short-term work zones TTC strategy. However, there is an evident need to study various TTC strategies for long-term work zones. This study investigated the operational impacts of two TTC strategies for work zones, namely static late and early merge control, using traffic data collected from Alabama Department of Transportation. VISSIM simulation experiments were designed to consider the factors of TTC strategy (i.e., static late and early merge); 3-to-1 lane drop configuration; and work-space length (500 – 1500 ft, with increments of 500 ft). The study findings show that long-term work zones with 3-to-1 lane closure can manage the traffic from midnight to early morning both with early and late merge traffic control for 500 ft long work zone. Short-term work zones perform better during non-peak hour both for 1000 and 1500 ft long work zones. However, no work zone traffic control was able to accommodate peak-hour short-term work zones. Under peak traffic conditions, speeds became lower than 10 mph with 1,000 ft lane closure with only one available lane for vehicle movement indicating severe congestion. The study concluded that 3-to-1 lane-drop configuration should not be scheduled for long-term duration. Maintenance work can be conducted with separate short-duration works, mostly avoiding peak-hour lane closures. These findings are expected to provide valuable guidance for agencies responsible for planning, design, and operations of work zones in the future.
Saha, Troyee, "Enhancing Work Zone Mobility Through Design And Control Of Lane Closures" (2019). All ETDs from UAB. 2882.