Freight can be efficiently transported between most locations in the country using large trucks.Number of trucks and vehicle miles traveled by trucks have both increased over the last severaldecades, thereby increasing the chances of more frequent truck crashes. Involvement of largetrucks in crashes can cause much damage and serious injuries, due to their large sizes and heavyweights. The purpose of this study was to identify the relationships between large truck crashesand traffic and geometric characteristics on limited access highways. Crash and traffic- andgeometric-related data for Kansas were utilized in this study. A Poisson regression model and anegative binomial regression model were developed for understanding the relationships betweenlarge truck crashes and traffic and geometric characteristics. Based on model-fitting statistics, thenegative binomial model was found to be the better model and was used to identify the importantcharacteristics. Significant variables in the negative binomial model were section length, numberof lanes, horizontal curvature, vertical grade, Annual Average Daily Traffic (AADT) per lane,large truck percentage, and inside shoulder width. Highway design features such as horizontalcurvature, vertical grade, and inside shoulder width are factors which can be implemented toprevent large truck crashes. By addressing identified factors, safety could be promoted throughintroduction of appropriate engineering improvements.
展开▼
