Paper Details

TRB 91st Annual Meeting (January 22-26, 2012)

Event Number:	498
Event Title:	Improved Safety Through Better Design for All Users
Event Date:	Jan 24 2012 8:30AM- 10:15AM
Event Location:	Shoreham, Blue Room Foyer
Event Description:
Event Agenda:

Maximizing Intersection Capacity and Improving Pedestrian Safety Through Unconventional Geometric Design of Continuous-Flow Intersections (12-3244)

Typical four-phase, four-legged intersections often operate inefficiently, severely restricting vehicle throughput and resulting in large delays. These configurations are limited by the traditional geometric design, and by altering the geometry of the entire intersection, the capacity can be significantly increased. Continuous flow intersections utilize an unconventional lane arrangement in order to maximize the vehicular throughput. This arrangement involves displacing left turn lanes across opposing through traffic before the main intersection is reached. Such an alteration allows left and through vehicles to proceed simultaneously, and consequently, both the intersection capacity and delay are improved. Numerous studies have validated the operational improvements associated with such a geometric design but in-depth analysis of this unconventional system can provide a maximized effect. In this paper, the authors have proposed improvement to the geometric design and developed an optimization model of a continuous flow intersection to increase intersection capacity. After defining the main objective functions and a list of constraints, preliminary tests were performed to show the effectiveness of the method adapting to changes in traffic demand. Then, the results found from the optimization were used to run simulation tests comparing the capacity and delay at a continuous flow intersection to those from a conventional four-legged geometric design. The results of several trials have strongly showed the optimum performance of the proposed unconventional geometric arrangement.

Authors
     Yi, Ping , University of Akron
     Coates, Angela , University of Akron
     Koganti, Sai Geetha , University of Akron
     Du, Yunke , University of Akron