00647262

Component

http://onlinepubs.trb.org...trr/1993/1421/1421-002.pdf

https://scholar.google.co...iams&publication_year=1993

The development of guidelines and recommendations for the selection of left-turn phasing and indication sequences at signalized intersections is documented in this paper. The guidelines developed are based on field studies and use easy-to-obtain data for the selection process. A simple three-level decision process regarding the most suitable left-turn phasing treatment to be used is established. The process favors the least restrictive permissive left-turn phase unless traffic and geometric conditions warrant the more restrictive protected/permissive or protected-only phasings. These guidelines are based on threshold values designed to determine what constitutes an excessive value for any particular variable, beyond which more restrictive left-turn phasing treatments may be justified. The guidelines developed also reflect a selection process that recognizes the trade-off between operational efficiency and safety. The study shows that selection of a particular phase is a multiobjective process involving a number of factors, and in many cases more than one condition must be met to justify the selection of a particular phase that will ensure an optimal solution.

This paper appears in Transportation Research Record No. 1421, Traffic Control Devices, Visibility, and Traffic Signal Systems. 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

01398730

English

p. 11-20

1993

Transportation Research Record

0309055741

Figures (4) ; References (17) ; Tables (6)

Alternatives analysis; Exclusive permissive phasing; Exclusive phasing; Guidelines; Left turn phase; Permissive phasing; Traffic safety

Operational efficiency

Highways; Operations and Traffic Management; I73: Traffic Control

TRIS, TRB

May 2 1994 12:00AM

• ANALYSIS OF FLASHING SIGNAL OPERATION
• DECISION SUPPORT SYSTEM FOR CONTROLLING TRAFFIC SIGNALS
• DEVELOPMENT OF AN EMERGENCY ZONE SIGN
• ENHANCEMENTS TO THE PASSER II-90 DELAY ESTIMATION PROCEDURES
• ENTRANCE ANGLE REQUIREMENTS FOR RETROREFLECTORIZED TRAFFIC SIGNS
• EVALUATION OF THE FEDERAL VISION STANDARD FOR COMMERCIAL MOTOR VEHICLE OPERATORS
• EXACT ROAD GEOMETRY OUTPUT PROGRAM FOR RETROREFLECTIVE ROAD SIGN PERFORMANCE
• HYBRID GENETIC ALGORITHM TO OPTIMIZE SIGNAL PHASING AND TIMING
• METHODOLOGY FOR EVALUATING TRAFFIC DETECTOR DESIGNS
• MICROSCOPIC SIMULATION MODELING OF MINIMUM THRESHOLDS WARRANTING INTERSECTION SIGNALIZATION
• OPERATIONAL COMPARISON OF LEADING AND LAGGING LEFT TURNS
• PASSER IV: A PROGRAM FOR OPTIMIZING SIGNAL TIMING IN GRID NETWORKS (WITH DISCUSSION AND CLOSURE)