Warrants for the installation of left-turn phasing in Kentucky were developed. A review of the literature was conducted, along with a survey of the policies of other states. Field data on delays and conflicts were taken before and after installation of exclusive left-turn signalization. Left-turn delay studies were conducted at intersections that had varying volume conditions. Analysis of the effect on accidents of adding a left-turn phase was made. The relationship between left-turn accidents and conflicts was investigated. Other types of analyses concerning gap acceptance, capacity, and benefit-cost ratios were also performed. It was found that exclusive left-turn phasing significantly reduced left-turn accidents and conflicts. This reduction was offset in part by an increase in rear-end accidents. Left-turn delay was reduced only during periods of heavy traffic flow. Total delay for an intersection increased after installation of left-turn phasing. Warrants were developed dealing with accident experience, delay, volumes, and traffic conflicts. (Author)
[1]
H Sofokidis,et al.
EVALUATION OF INTERSECTION-DELAY MEASUREMENT TECHNIQUES
,
1973
.
[2]
J E Leisch.
CAPACITY ANALYSIS TECHNIQUES FOR DESIGN OF SIGNALIZED INTERSECTIONS - INSTALLMENT NO 2 PART IV - HIGH TYPE FACILITIES AND INTERCHANGES
,
1967
.
[3]
J Behnam.
Gap acceptance as a criterion for left turn phasing
,
1972
.
[4]
G Gurnett.
INTERSECTION DELAY AND LEFT TURN PHASING
,
1969
.
[5]
Taro Yamane.
Statistics: An Introductory Analysis
,
1965
.
[6]
Stuart R Perkins,et al.
Traffic conflict characteristics-accident potential at intersections
,
1968
.
[7]
William T Baker,et al.
AN EVALUATION OF THE TRAFFIC CONFLICTS TECHNIQUE
,
1972
.