Investigation of head response to blast loading

Abstract

Background: Head injury resulting from blast loading, specifically mild traumatic brain injury, has been identified as a possible and important blast-related injury for soldiers in modern conflict zones. A study was undertaken to evaluate head response to blast loading scenarios using an explicit finite element numerical model and to comment on the potential for head injury.

Methods: The blast loading and simplified human body numerical models were validated using impulse, peak acceleration and the Head Injury Criterion from experimental blast test data. A study was then undertaken to evaluate head response at varying distances and orientations from the explosive.

Results: The accelerations and injury metrics for the head increased with decreasing distance to the explosive, as expected, but were also significant at intermediate distances from the explosive for larger charge sizes and intermediate heights of burst. Varying lateral position with constant standoff did not have a significant effect on the head kinematic response.

Conclusions: The head injury criteria considered were exceeded in close proximity to the explosive (<35 charge radii) and depended on the height of burst for the range of charge sizes considered. The injury criteria were also exceeded at intermediate distances for larger charge sizes because of the influence of the mach stem. Although the injury criteria used in this study are typically applied to longer duration events, and may not be applicable for shorter duration blast loading, aggressive loading is predicted at small standoff distances and confirmed by the resulting head kinematics.