estimation of freeway traffic congestion using probe …€¦ · o van aerde model •full year...
TRANSCRIPT
DATE 6/27/2017
ESTIMATION OF FREEWAY TRAFFIC CONGESTION USING PROBE VEHICLE DATA -A CASE STUDY IN SANTA CLARA COUNTY
Anusha Musunuru, Aaron Elias, Mike Aronson
2018 ITE Joint Western & Texas District Meeting
Presentation Overview
• Background• Data Sources• Methodology• Case Study Results• Next Steps• Questions?
Presentation Overview
• Background• Data Sources• Methodology• Case Study Results• Next Steps• Questions?
Background
• Freeway Level of Service (LOS)• Congestion Management Program (CMP)• CMP network• Trends in travel speeds• Congested segments,.......
Background
• Future transportation needs• Alleviate congestion• Informed decisions
Background
• Santa Clara County • 155 miles of freeway• AM and PM peak periods
Source: https://www.worldatlas.com/na/us/ca/c-santa-clara-county-california.html
Presentation Overview
• Background• Data Sources• Methodology• Case Study Results• Next Steps• Questions?
Data Sources
• Performance Measureso LOSo Duration of Congestion
• Data Sourceso Aerial Photographyo Floating car runs
Data Sources
• Data Sourceso Floating car runs (HOV)o INRIX Data
Presentation Overview
• Background• Data Sources• Methodology• Case Study Results• Next Steps• Questions?
Methodology
Density-Speed Relationship
Methodology
• Mixed Flow Laneso Traffic message channels (TMC)o Merge and diverge points of Rampso Travel speed and travel time for each TMC
Methodology
• HOV Laneso INRIX data cannot separate HOV lane performance datao Floating vehicle surveyso Two mid-week days
o 6:15 am – 9:45 amo 3:15 pm – 6:45 pm
Data Processing
• Mixed Flow Laneso Filter raw datao Calculate 20th Percentile Speed
o ~80th Percentile Travel Time
o Speed contour mapso LOS – based on travel speedso Duration of congestion
Mixed Flow Lanes
• Filter raw datao Data ‘Quality Score’o Score of 30/20/10o Missing datao Midweek days – September & October
• Calculate 20th Percentile Speedo Speed that 20 percent of days – do not exceedo Avoid days with crashes, work zones, and special eventso Worst case in “typical” dayo Recurrent congestion
Mixed Flow Lanes
• Speed contour maps
Mixed Flow Lanes
• LOS calculationo Minimum travel speedo AM and PM peak periods
• Duration of congestiono Speed contour mapso Each TMC segment
Data Processing
• HOV Laneso Same TMC segmentationo No crash, construction/work zone, evento Travel speeds averagedo LOSo No duration of congestion
Presentation Overview
• Background• Data Sources• Methodology• Case Study Results• Next Steps• Questions?
Case Study Results
• Freeway Speed, LOS, Estimated Density, Estimated Flow
Case Study Results
• Freeway Miles LOS
Mixed Flow Lanes HOV Lanes
Case Study Results
• US 101 Congestion Duration (as a Percent of Directional Miles)
Case Study Results
• Duration of Congestion
Presentation Overview
• Background• Data Sources• Methodology• Case Study Results• Next Steps• Questions?
Next Steps
• Results Comparisono LOS, Speed, Density Comparisono Van Aerde Model
• Full year datao Speed datao TMC level analysis
• Reliability Metricso Travel time indexo Planning time index
Presentation Overview
• Background• Data Sources• Methodology• Case Study Results• Next Steps• Questions?
Questions??