Determinants of injury severity for truck crashes on mountain expressways in China: A case-study with a partial proportional odds model

The fast economic growth in China has dramatically increased the number of heavy traffic and the length of the expressway network, with consequent road safety issues emerging in particular in mountainous expressways. This study positions itself at the intersection of these issues by analysis determinants of injury severity for truck crashes on mountainous expressways in China. A sample of 2695 heavy truck crashes occurring on four mountain expressways in Jiangxi and Shaanxi (China) between 2006 and 2015 was analysed to uncover the effect on crash injury severity of geometric, driver, crash, truck and environmental characteristics. Given that the expansion of the expressway network is underway, model findings focused on the effect of geometric characteristics and suggested that road design should have curves that are neither too sharp nor too long, as well as longitudinal gradients not too steep. Also, model findings indicated a need for the toughening of deterrence measures and the bolstering of police enforcement with respect to aberrant driver behaviour (e.g., driving without a valid license, without seat belts, or while intoxicated) and most relevantly overloading of the trucks.