Understanding Factors Affecting Arterial Reliability Performance Metrics

Avinash Unnikrishnan, Portland State University

Co-investigators:

Summary:

In recent years, the importance of travel time reliability has become equally important as average travel time. However, the majority focus of travel time research is average travel time or travel time reliability on freeways. In addition, the identification of specific factors (i.e., peak hours, nighttime hours, etc.) and their effects on average travel time and travel time variability are often unknown. The current study addresses these two issues through a travel time-based study on urban arterials. Using travel times collected via Bluetooth data, a series of analyses are conducted to understand factors affecting reliability metrics on urban arterials. Analyses include outlier detection, a detailed descriptive analysis of select corridors, median travel time analysis, assessment of travel time reliability metrics recommended by the Federal Highway Administration (FHWA), and a bivariate Tobit model. Results show that day of the week, time of day, and holidays have varying effects on average travel time, travel time reliability, and travel time variability. Results also show that evening peak hours have the greatest effects in regards to increasing travel time, nighttime hours have the greatest effects in regards to decreasing travel time, and directionality plays a vital role in all travel time-related metrics.

Impacts:

The research project will first attempt to answer the following questions through literature review and interaction with practitioners:  
•	What reliability related metrics are currently being used or being considered for use in traffic planning and operations, by practitioners and researchers for quantifying travel time reliability along arterial corridors?
•	What are the data requirements for quantifying the metrics? 
•	How easy or difficult is it to get an accurate estimate for each metric with existing data collection practices? 

Project Details

Project Type:
Research
Project Status:
Completed
End Date:
June 30,2019
UTC Grant Cycle:
NITC 16 Round 1
UTC Funding:
$99,994

Other Products

  • Travel Time Metrics and Temporal Effects: Analysis of Urban Arterials Using Bluetooth Data (PRESENTATION)
  • In Review: Transportation Research Part A (PUBLICATION)
  • In Review: Annual Meeting of the Transportation Research Board (PUBLICATION)