Performance Analysis of Isolated Intersection Traffic Signals

This dissertation analyzes two unsolved problems to fulfill the gap in the literature: (1) What is the vehicle delay and intersection capacity considering left-turn traffic at a pre-timed signal? (2) What are the mean and variance of delay to vehicles at a vehicle-actuated signal? The first part of this research evaluates the intersection performance in terms of capacity and delay at an isolated pre-timed signal intersection. Despite a large body of literature on pre-timed signals, few studies have examined the interactions between left-turn and through vehicles. In order to examine this missing piece in studies of signalized intersections, two probabilistic models are proposed to deal with the left-turn bay blockage and queue spillback in a heuristic manner. The second part of this research studies an isolated intersection with a vehicle-actuated signal. The actuated system dynamically allocates the green time among multiple approaches according to vehicle arrivals. A model is developed to study vehicle delay under a general arrival distribution with a given unit extension. The model allows optimizing signal performance over the unit extension. The third part of this research applies graphical methods and diffusion approximations to traffic signal problems. A graphical method originally proposed by Newell is reinterpreted in order to directly measure the variance of time for queue clearance at a signalized intersection. Furthermore, the problem of disruptions occurring during a pre-timed traffic signal cycle is investigated. The quantitative estimation of the duration that the effects of disruptions dissipate is provided by diffusion approximation.


  • English

Media Info

  • Media Type: Digital/other
  • Features: Appendices; Figures; References; Tables;
  • Pagination: 142p

Subject/Index Terms

Filing Info

  • Accession Number: 01496669
  • Record Type: Publication
  • Report/Paper Numbers: SWUTC/13/600451-00021-1
  • Contract Numbers: DTRT12-G-UTC06
  • Created Date: Oct 28 2013 9:47AM