A Comparative Analysis of Factors Affecting Injury Severities of Large-Truck-Involved and Non-Large-Truck-Involved Interstate Crashes

Large trucks and interstate highways play critical roles for freight transportation in the US (United States). However, a significant proportion of fatal crashes involving large trucks occur on interstate roads. This impacts the smoother operation of freight transportation and national economy. A couple of studies have investigated the factors that contribute to the severity of injuries in crashes involving large trucks. However, until the differences in the effects of factors that contribute to the severity of injuries in large-truck-involved and non-large-truck-involved interstate crashes are revealed, the countermeasures are less likely to be effective. The current study has developed two separate mixed logit (or random parameter logit) models on interstate crashes that occurred in the south region of the United States between 2016 and 2019 for a comparative analysis between interstate crashes involving large trucks and those without large trucks. In the models, the effects of crash characteristics, roadway attributes, traffic condition, environmental factors, driver and vehicle related factors on injury outcomes (i.e., no-injury, non-severe & serious injuries) were explored. The empirical results indicated that certain contributory factors are unique to large-truck-involved interstate crashes, and the effects of most of the contributory factors on non-severe and serious injuries are higher in interstate crashes involving large trucks than those without large trucks. The study has recommended some preventive measures to avoid interstate crashes involving large trucks based on the findings.