Head Kinematics Resulting from Simulated Blast Loading Scenarios

Blast wave overpressure has been associated with varying levels of traumatic brain injury in soldiers exposed to blast loading. In realistic blast loading scenarios, the mechanisms of primary blast injury are not well known due to the complex interactions of the blast wave with the human body, and the high acceleration experienced over very short time durations. The purpose of this study was to investigate head kinematics resulting from a range of simulated blast loading conditions corresponding to varying standoff distances, and differing heights of burst. This study considered peak linear acceleration, and the head injury criteria (HIC) to examine the effect of blast wave interaction on head kinematics using a validated multi-body model. A modified version of the GEnerator of Body Data (GEBOD) 50percentile male was validated against experimental blast data using a Hybrid III 50 percentile male ATD. The blast wave was applied using an air blast function via the application of pressure loads corresponding to the detonation of a conventional spherical charge using an equivalent mass of TNT. This approach applied the blast shockwave, a rapid increase in pressure, temperature and density, and included Mach stem effects. As expected, the results demonstrated that head acceleration increased with decreased charge standoff distance, and severe head injury may occur in close proximity to blast as the head injury criterion threshold was exceeded for all explosive sizes at close proximity. The presence of a Mach stem resulting from an elevated charge has been found to increase the potential injury zone surrounding an explosive charge compared to a free field blast; this could be addressed through increased standoff or enhanced blast protection.