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Title:

Quantification of the Effects of Geometric Features on Operational Performance of Triple Left-Turn Intersections

Accession Number:

01004438

Record Type:

Component

Availability:

Transportation Research Board Business Office

500 Fifth Street, NW
Washington, DC 20001 United States

Abstract:

Intersection operational performance is highly influenced by the intersection geometric features. This fact can be demonstrated in the operations of non-traditional intersections such as triple left-turn lanes intersections. Triple left-turn lanes intersections are designed to combat high left-turn demand in a signalized area, predominantly in urban intersections. The existence of different geometric features at different triple left-turn intersections causes different magnitudes of saturation flows among the intersections. This paper discusses the study that was conducted to determine the influence of different geometric features on the operations of triple left-turn lanes. The geometric features studied include the skewness of the left-turn angle, the approach slope, the type of street--one way versus two ways, and lane type--innermost, middle and outermost lanes. Other features studied were curvature of the approach lanes, shadowing effect and intersection type--four legs versus T-intersection. Field data were collected at 15 triple left-turn intersections in Florida. Four traffic measures were used to quantify the effects of the mentioned geometric features--saturation flows, lane utilization factors, lane usage factors and left-turn factors. The results indicate that the approach grade, intersection skewness and the type of street highly influence the operational performance of triple left-turn lanes. Intersection type and lane type did not significantly influence the operation of triple left-turn lanes.

Monograph Accession #:

01004374

Language:

English

Corporate Authors:

Transportation Research Board

500 Fifth Street, NW
Washington, DC 20001 United States

Authors:

Sando, Thobias
Mussa, Renatus N

Pagination:

14p

Publication Date:

2005

Conference:

3rd International Symposium on Highway Geometric Design

Location: Chicago Illinois, United States
Date: 2005-6-29 to 2005-7-1
Sponsors: Transportation Research Board; American Association of State Highway and Transportation Officials (AASHTO); Federal Highway Administration; American Society of Civil Engineers; Association Mondiale de la Route; International Road Federation; Institute of Transportation Engineers (ITE); National Association of County Engineers; Transportation Association of Canada (TAC); Chicago Department of Transportation; Illinois Department of Transportation; Illinois State Toll Highway Authority

Media Type:

CD-ROM

Features:

Figures (2) ; Photos (3) ; References (7) ; Tables (3)

Geographic Terms:

Subject Areas:

Design; Highways; I20: Design and Planning of Transport Infrastructure

Files:

TRIS, TRB, ATRI

Created Date:

Sep 30 2005 11:38AM