Application of Dynamic Traffic Assignment in a Small-Urban Area

Many attempts had been made to improve the highway assignment component of a four-step travel demand model, in such that the model would generate more realistic speed and travel time estimates. These estimates determined performance measures, which were used to evaluate projects and help policy makers to make decisions in the planning process. With the help of advanced computer technology, and research and development efforts, dynamic traffic assignment (DTA) had become a viable modeling option. This paper explored the benefits of applying the DTA methodology in a small urban environment and the implications in planning analysis. Unlike in static assignment, where time and speed were unrealistically assumed to be constant over a period of analysis time and that the results of one analysis period did not affect the next analysis period, DTA assumed that travel time and speed changed by time segment and that the results of one time segment would affect the next time segment. In DTA the demand trips were assumed to enter the network over the course of the model time period and that no link would handle more traffic than its capacity. These features would conceptually enable DTA to produce results that were more reflective to reality. A case study was conducted for Morristown, a small urban town in New Jersey with a population of 18,500. Two assignment applications, static and DTA were developed using the Cube software. Input data was obtained from subarea-extraction of the Morris County Transportation Model. The assignment methodologies were tested using two hypothetical network scenarios. The analysis results were compared and the assignment methodologies were evaluated. This study also demonstrated a process of developing a DTA assignment application for a small urban area based on a regional model.

Language

  • English

Media Info

  • Media Type: Digital/other
  • Features: CD-ROM; Figures; Maps; References; Tables;
  • Pagination: 12p
  • Monograph Title: Tools of the Trade: 12th National Conference on Transportation Planning for Small and Medium-Sized Communities

Subject/Index Terms

Filing Info

  • Accession Number: 01485242
  • Record Type: Publication
  • Files: TRIS, TRB, ATRI
  • Created Date: Jun 27 2013 2:21PM