All ETDs from UAB

Advisory Committee Chair

Virginia P Sisiopiku

Advisory Committee Members

Nasim Uddin

Robert W Peters

Document Type


Date of Award


Degree Name by School

Master of Science in Civil Engineering (MSCE) School of Engineering


Oversaturated conditions on arterial networks are a concern for both transportation agencies and the traveling public. The cost of construction, right-of-way constraints, and a variety of environmental, political, and other social issues often prohibit facility expansion and place extra emphasis on optimizing the operations of existing facilities. One of the options available to urban planners and transportation professionals for handling recurring and non-recurring oversaturation conditions in arterial networks is traffic signal optimization. The objective of this study is to develop a better understanding of traffic signal system performance in oversaturated conditions. The case study reported in this research focuses on the analysis of recurring oversaturated conditions and non-recurring oversaturated conditions along McFarland Boulevard (US-82) in the city of Tuscaloosa, Alabama. The Visual Interactive System for Transport Algorithm (VISTA) platform was used to model the city of Tuscaloosa traffic network, including the study corridor. VISTA is a mesoscopic simulation tool with Dynamic Traffic Assignment (DTA) capabilities for modeling real-time traffic conditions and spatio-temporal paths for each vehicle. Several study scenarios were developed by varying traffic and control conditions and tested on the VISTA Tuscaloosa model in order to assess the impact of excess demand on traffic operations along the study corridor and in the entire network. Moreover, signal timing optimization studies were performed using a VISTA model with existing and optimal ii signal settings under varying capacity and demand conditions. The study confirmed that optimization of travelers’ paths, coupled with signal timing optimization could be beneficial in mitigating congestion in arterial networks and improving local and regional mobility.

Included in

Engineering Commons



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