OBJECTIVES

The major purpose of this study was to identify risk factors affecting truck crashes on freeways and propose recommendations for safer truck traffic operations.

METHODS

Truck crashes were analyzed to identify how truck traffic safety is related to prevailing traffic and weather conditions. Prevailing traffic conditions were characterized by central tendencies and the spatiotemporal variation of traffic parameters collected from freeway traffic surveillance systems. A total of 377 truck crashes occurring on Korean freeways in a recent 3-year period, 2008-2010, were analyzed together with corresponding prevailing traffic conditions and weather conditions. Several statistical tests were conducted to understand the characteristics of prevailing traffic conditions before crash occurrence based on different weather conditions. In addition, a binary logistic regression technique was applied to identify causal factors affecting truck crash severity under normal and adverse weather conditions.

RESULTS

Major findings from the analyses are discussed with truck operations strategies including speed enforcement, variable speed limit, and truck lane restriction from the safety enhancement point of view. Speed-related variables representing prevailing traffic conditions before crash occurrences were found to be the most statistically significant factors affecting truck crash severity, compared to volume-related variables such as the volume-to-capacity ratio (v/c). It is inferred that speed management is an effective tool for safer truck traffic operations on freeways. The major findings can be further discussed to derive valuable insights into truck traffic operations based on different weather conditions, such as normal and adverse.

CONCLUSIONS

Some recommendations for safer truck traffic operations were presented based on the results obtained. The outcomes of this study could be effectively utilized to support the development of various traffic operations strategies and policies for truck traffic safety. Supplemental materials are available for this article. Go to the publisher's online edition of Traffic Injury Prevention to view the supplemental file.