Arterial Signal Timing and Coordination: Sensitivity Analyses and Partition Techniques

This paper addresses two issues regarding arterial signal coordination and traffic progression: 1) It presents a sensitivity analysis of determining the optimal network cycle length under various combined options chosen among increment in cycle length, whether and how to allow uncoordinated, and ways to conduct offset optimization; and 2) It compares the effectiveness of three different network partition techniques which can be potentially incorporated into software packages. A case study is undertaken using a real world arterial in the City of Tyler, Texas. Numerical results indicate that using the Quick Offset Optimization command during the process of optimizing cycle length may not be sufficient enough to find the best signal timing plans and this is particularly true if intersections are allowed uncoordinated to a certain extent (ranging from Rarely, to Sometime, to Often). It is also found that the three different partition techniques (i.e., Coupling Index, Strength of Attraction, and Coordinatability Factor) differ only slightly and can produce the same solutions in all scenarios.