00714896

Component

http://onlinepubs.trb.org...trr/1995/1494/1494-004.pdf

https://scholar.google.co...dwan&publication_year=1995

Incidents are a major cause of travel delays on urban freeways. This paper describes development and application of a new method for estimating freeway incident congestion where extensive loop and incident data are available. Using shock wave analysis, a time-space domain is determined for each incident. This is used to define the congestion boundaries of an incident and to decide whether the incident should be analyzed as isolated or as a multiple-incident case. The freeway section is divided into smaller segments, each segment containing only one mainline loop station. Traffic speed and counts at freeway mainline stations and traffic counts at on/off ramp stations upstream and downstream of the incident location are used to calculate incident delay on each segment during small time slices, then cumulative incident delay is calculated. Satisfactory results were achieved when the new method was applied to a sample of isolated and multiple-incident cases collected recently as part of the Freeway Service Patrol Evaluation Project on I-880 in Alameda County, California.

This paper appears in Transportation Research Record No. 1494, Traffic Operations, Traffic Signal Systems, and Freeway Operations 1995. Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved

01399825

English

p. 30-39

1995

Transportation Research Record

Figures (4) ; References (11) ; Tables (3)

Analysis; Calculation; Case studies; Estimating; Freeways; Shock waves; Traffic congestion; Traffic counts; Traffic delays; Traffic incidents; Traffic speed; Urban areas

Incidents

Alameda County (California)

Alameda County (California)

Highways; Operations and Traffic Management; I71: Traffic Theory

TRIS, TRB, ATRI

Dec 13 1995 12:00AM

• A CASE FOR FREEWAY MAINLINE METERING
• ANALYSIS OF TEMPORAL AND SPATIAL VARIABILITY OF FREE SPEED ALONG A FREEWAY SEGMENT
• ARTIFICIAL NEURAL NETWORKS FOR FREEWAY INCIDENT DETECTION
• BUS-PREEMPTION UNDER ADAPTIVE SIGNAL CONTROL ENVIRONMENTS
• CALTRANS INTERSTATE 15 REVERSIBLE HIGH-OCCUPANCY LANES: 1994 STATUS
• COSTS AND BENEFITS OF VISION-BASED, WIDE-AREA DETECTION IN FREEWAY APPLICATIONS
• DESIGN OF INCIDENT DETECTION ALGORITHMS USING VEHICLE-TO-ROADSIDE COMMUNICATION SENSORS
• DEVELOPMENT OF A FREEWAY CONGESTION INDEX USING AN INSTRUMENTED VEHICLE
• DEVELOPMENT OF ADVANCED TRAFFIC SIGNAL CONTROL STRATEGIES FOR INTELLIGENT TRANSPORTATION SYSTEMS: MULTILEVEL DESIGN
• EVALUATION OF MINNESOTA I-394 HIGH-OCCUPANCY-VEHICLE TRANSPORTATION SYSTEM
• EXAMINING THE POTENTIAL OF USING RAMP METERING AS A COMPONENT OF AN ATMS
• INCIDENT MANAGEMENT VIA COURTESY PATROL: EVALUATION OF A PILOT PROGRAM IN COLORADO
• MODEL TO EVALUATE THE IMPACTS OF BUS PRIORITY ON SIGNALIZED INTERSECTIONS
• PIONEER APPLICATION OF PASSER IV IN THE HOUSTON METRO-RCTSS PROJECT
• REALBAND: AN APPROACH FOR REAL-TIME COORDINATION OF TRAFFIC FLOWS ON NETWORKS
• REALTRAN: AN OFF-LINE EMULATOR FOR ESTIMATING THE EFFECTS OF SCOOT
• TECHNIQUES TO ASSESS DELAY AND QUEUE LENGTH CONSEQUENCES OF BUS PREEMPTION
• TESTING OF LIGHT RAIL SIGNAL CONTROL STRATEGIES BY COMBINING TRANSIT AND TRAFFIC SIMULATION MODELS
• UNIFORM AND VARIABLE BANDWIDTH ARTERIAL PROGRESSION SCHEMES
• VALIDATION OF SIMULATION SOFTWARE FOR MODELING LIGHT RAIL TRANSIT