01336765

Component

https://doi.org/10.3141/2229-04

http://scholar.google.com...mpin&publication_year=2011

An empirical, corridor-level method is proposed to divide the travel time unreliability or variability over a freeway section into the following components: incidents, weather, work zones, special events, and inadequate base capacity or bottlenecks. The method consists of three steps: (a) corridor-level aggregation of travel time and source data, (b) quantile regression to fit the 95th percentile of travel time on the source variables, and (c) calculation of the contribution of individual sources to the buffer time. It could be applied to other percentile-based travel time reliability measures such as planning time and 90th and 95th percentiles. Once the source data are defined, the method can be automatically applied to any site with minimum calibration. When applied to a 30.5-mi section of northbound I-880 in the San Francisco Bay Area, California, the method revealed that traffic accidents contributed 15.1% during the morning and 25.5% during the afternoon, among others, and most of the remaining reliability came from recurrent bottlenecks. Quantifying the components of travel time variability at individual freeway sites is essential in developing effective strategies to mitigate congestion.

01352852

11-3106

English

pp 28-33

2011

Transportation Research Record: Journal of the Transportation Research Board

9780309167383

Print

Figures (2) ; Maps (2) ; References (14) ; Tables (2)

Bottlenecks; Freeways; Highway capacity; Peak hour traffic; Special events; Traffic congestion; Traffic crashes; Traffic incidents; Travel time; Weather conditions; Work zones

Interstate 880

Travel time reliability; Travel time variability

San Francisco Bay Area

Highways; Operations and Traffic Management; I71: Traffic Theory; I73: Traffic Control

TRIS, TRB, ATRI

Feb 17 2011 6:24PM

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• Managing Highways for Better Reliability: Assessing Reliability Benefits of Ramp Metering
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• Quantifying the Attractiveness of High-Occupancy Toll Lanes with Traffic Sensor Data Under Various Traffic Conditions
• Safety Benefits from Deployment of Open Road Tolling for Main-Line Toll Plazas in Florida
• Spatiotemporal Patterns of Primary and Secondary Incidents on Urban Freeways
• Validation Techniques for Region-Level Microscopic Mass Evacuation Traffic Simulations