Turner-Fairbank Highway Research Center

 
 
 
 
« back to the list

Development of Relationship Between Truck Accidents and Geometric Design: Phase 1. Final Report

Product Type

Research Report

Author

S.-P. Miaou, P.S. Hu, T. Wright, S.C. Davis, and A.K. Rathi

Date

Aug-93

Abstract

The purpose of this study was to establish empirical relationships between truck accidents and highway geometric design. First, statistical frameworks based on Poisson and negative binomial regression models were proposed. Preliminary models were then developed using accidents and road inventory data from the Highway Safety Information System (HSIS). Three roadway classes were considered in the model development: rural Interstate, urban Interstate and freeway, and rural two-lane undivided arterial. The maximum likelihood method was used for estimation of model parameters. Information criterion, asymptotic t-statistic, and goodness-of-fit test statistics were employed to evaluate the estimated models. The model results based on data from one of the HSIS States--Utah, were used for analysis and for suggesting areas in which the quality and quantity of the existing HSIS data can be enhanced to improve the developed models. Despite the limitations in existing Utah data, some encouraging preliminary relationships were developed for horizontal curvature, length of curve, vertical grade, length of grade, shoulder width, number of lanes, and annual average daily traffic (AADT) per lane (a surrogate measure for vehicle flow density). Goodness-of-fit test statistics indicated that extra variations (or overdispersion) existed in the data over the developed Poisson models for all three roadway classes. Subsequent analyses suggested that a future study can be performed to enhance the predictive power of these preliminary models by including detailed truck exposure information, e.g., time-of-day, truck type, and weather conditions, by considering more explanatory variables, such as roadside design and superelevation, and by reducing the sampling errors of vehicle exposure data (both AADT and truck percentages).

Link To Research Report

Link not available.

Keywords

Truck crashes
Poisson regression models
Highway geometric design
HSIS


« Back to the List

HSIS Summaries

HSIS Summary Reports are two to eight pages in length and include a brief description of the issue addressed, data used, methodology applied, significant results, and practical implications.

Read More

Research Reports

A variety of research studies have been performed using data from HSIS. Many of the final reports prepared are now available electronically.

Read More

Technical Summaries

Research reports are often summarized in executive summaries, technical briefs, or other abbreviated formats. Included here are those road safety summaries that involved research using HSIS data.

Read More

Safety Analysis Tools

In addition to conducting research, HSIS resources are also used to develop products that can be used by practitioners in the analysis of safety problems.

Read More

Other Projects

HSIS data are sometimes used in research studies that result in other types of finished products, such as dissertations, theses, and conference proceedings.

Read More