01091657

Component

Over the past couple of decades, Iowa has converted several 2-lane urban roadways to 3-lane sections. Most of these have been on low volume roads in smaller communities. However, no evaluation of the effectiveness of these conversions had been attempted. Iowa has recently evaluated the safety impacts of these conversions using a Bayesian approach. Within this paper, initial, tentative results of the analyses are explored, with emphases on the data, results, and possible future applications of these conversions. Relative to total crash history, results are mixed, with some sites indicating a reduction and others indicating an increase in both crash frequency per mile and crash rate.

01091711

English

15p

2007

3rd Urban Street Symposium: Uptown, Downtown, or Small Town: Designing Urban Streets That Work

CD-ROM

Figures (3) ; References (31) ; Tables (6)

Bayes' theorem; Crash locations; Crash rates; Highway safety; Impact studies; Low volume roads; Three lane highways; Traffic crashes; Two lane highways

Iowa

Design; Highways; Planning and Forecasting; Safety and Human Factors; I21: Planning of Transport Infrastructure; I82: Accidents and Transport Infrastructure

TRIS, TRB

Mar 31 2008 12:12PM

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• Geometric Design of Interchange in Urban City
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• Integrating Context Sensitive Solutions into University Transportation Education
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