The Effect of Optimal Arterial Cycle Length on Intersection Delays in a Coordinated Arterial System

• Activity Number: 23
• Type: Topic Contributed
• Date/Time: Sunday, August 7, 2005 : 2:00 PM to 3:50 PM
• Sponsor: Section on Government Statistics
• Author(s): Mohammad Qureshi*+ and Gary Gadbury and Navin Sugathan
• Companies: University of Missouri, Rolla and University of Missouri, Rolla and KCI Technologies
• Keywords: traffic signals ; cycle length ; confidence intervals

Abstract

Coordinating the intersections along an arterial is now a common practice to reduce the delays for vehicles traveling through the arterial. However, coordinating the intersections in an arterial may not necessarily guarantee a decrease in intersection delay. When the intersections are coordinated, a common arterial optimal cycle length, which may not be the optimal cycle length for the intersections, is provided to all the intersections. This may cause increase in delay at some intersections and the benefits of the coordination may be lost. This paper compares the delay at the intersections at their optimal cycle length and at arterial optimal cycle length to understand how the delay is affected. Data were provided by MoDOT (Missouri Department of Transportation) for a section of Manchester Road consisting of 22 intersections. Statistical analyses includes confidence interval estimation and Bonferroni's confidence interval estimation to determine significant differences in delay before and after coordination. From the results obtained from the study, it was found the delay was decreasing for the intersections at arterial optimum intersection cycle length.