Characterisation and investigation of serious thoracic injuries in passenger vehicle rollover crashes

Abstract

Passenger vehicle rollover crashes involving a single vehicle occur infrequently; however, when they do the vehicle occupants in these crashes are more likely to sustain serious and fatal injuries compared to other crash modes. The thorax is frequently seriously injured in rollover crashes. Ongoing efforts in the USA and Australia have sought to understand the characteristics and aetiology of these injuries. Despite these efforts, the characteristics and aetiology of thoracic injuries in rollover crashes are still not well understood. It has been hypothesised that these injuries are occurring as a result of occupant flailing within the vehicle during the rollover crash event. Four studies were performed and documented in this thesis to address this identified knowledge gap. Firstly, Flail-space’s lateral thoracic impact velocity was validated against existing lateral PMHS thoracic impact tests. The validated velocity was then used as an injury criterion for assessing lateral thoracic injuries resulting from rollover crashes. Secondly, thoracic injuries from real-world vehicle rollover crashes were examined based on occupant seated position and vehicle rollover direction. The results indicated that there is a difference in resultant thoracic injuries based on occupant seated position and rollover direction. Thirdly, correlations between vehicle panel damage and serious thoracic injuries were investigated from real-world rollover crashes. The results indicated that there are associations between vehicle panel damage and serious thoracic injuries. Fourthly, two real-world rollover crash where the driver sustained serious thoracic injuries were analysed using computer simulations to study thoracic injury aetiology and its association with vehicle panel damage, as identified in the third study. Thoracic injuries were then assessed against existing thoracic injury criteria and the lateral thoracic impact velocity criterion from the first study. The results of the analysis indicate two instances in a rollover crash where, indeed, serious thoracic injuries occurred as a result of occupant flailing during the event, thus, confirming the hypothesis.