01123174

Component

https://doi.org/10.3141/2103-01

http://scholar.google.com...Vadi&publication_year=2009

The forthcoming first edition of the "Highway Safety Manual" (HSM) will introduce safety predictive models both for road segments and intersections. A key issue for allowing HSM to become a standard for road owners and managers worldwide is the transferability of the predictive models to different networks. The application of the calibration procedure of the HSM model to different countries has been evaluated, with all practical and potential application problems outlined. In this study, the calibration procedure of the HSM model has been applied to the road network of the Italian province of Arezzo to evaluate the effective transferability of this methodology to a region characterized by a different environment and different road characteristics, driver behavior, and crash reporting systems than those on which the HSM models have been developed. The considered road network covers 1,300 km of rural two-lane highways located in the Arezzo province, and a 3-year (2002–2004) accident database has been used. The considerable difference between the road network of the Italian province of Arezzo and the one of Minnesota, for which the HSM model has been developed, causes practical application problems, mainly related to segmentation and overestimation of curvature effects, which are discussed in the paper. Four approaches to define the calibration factor have been applied and discussed to determine the most effective one. Finally, this work points out the problems related to the identification of data needs and necessary treatments for the HSM model calibration and application.

01138796

09-1256

English

pp 1-9

2009

Transportation Research Record: Journal of the Transportation Research Board

9780309126182

Print

Figures (6) ; References (9) ; Tables (5)

Calibration; Crash rates; Databases; Highway safety; Intersections; Mathematical models; Mathematical prediction; Rural highways; Traffic crashes; Two lane highways

Highway Safety Manual

Crash prediction models; Transferability of models

Arezzo (Italy : Province); Minnesota

Highways; Planning and Forecasting; Safety and Human Factors; I72: Traffic and Transport Planning; I81: Accident Statistics

TRIS, TRB, ATRI

Jan 30 2009 5:28PM

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