Citation

Tan LB, Chew FS, Tse KM, Tan VB, Lee HP. Int. J. Numer. Method. Biomed. Eng. 2014; 30(12): 1476-1505.

Affiliation

Department of Mechanical Engineering, National University of Singapore, Singapore.

Copyright

(Copyright © 2014, John Wiley and Sons)

DOI

10.1002/cnm.2668

PMID

25132676

Abstract

Head injuries due to complex blasts are not well examined due to limited published articles on the subject. Previous studies have analyzed head injuries due to impact from a single planar blast wave. Complex or concomitant blasts refer to impacts usually caused by more than a single blast source, whereby the blast waves may impact the head simultaneously or consecutively, depending on the locations and distances of the blast sources from the subject, their blast intensities, the sequence of detonations, as well as the effect of blast wave reflections from rigid walls. It is expected that such scenarios will result in more serious head injuries as compared to impact from a single blast wave, due to the larger effective duration of the blast. In this paper, the utilization of a head-helmet model for blast impact analyses in Abaqus™ is demonstrated. The model is validated against studies published in literature.

RESULTS show that the skull is capable of transmitting the blast impact to cause high intracranial pressures. In addition, the pressure wave from a frontal blast may enter through the sides of the helmet and wrap around the head to result in a second impact at the rear. This study recommended better protection at the sides and rear of the helmet through the use of foam pads so as to reduce wave entry into the helmet. The consecutive frontal blasts scenario resulted in higher intracranial pressures (ICPs) compared to impact from a single frontal blast. This implied that blast impingement from an immediate subsequent pressure wave would increase severity of brain injury. For the unhelmeted head case, a peak ICP of 330 kPa is registered at the parietal lobe which exceeds the 235 kPa threshold for serious head injuries [9]. The concurrent front and side blasts scenario yielded lower ICPs and skull stresses than the consecutive frontal blasts case. It is also revealed that the additional side blast would only significantly affect ICPs at the temporal and parietal lobes when compared to results from the single frontal blast case. By analyzing the pressure wave flow surrounding the head and correlating them with the consequential evolution of ICP and skull stress, the paper provides insights into the interaction mechanics between the concomitant blast waves and the biological head model. This article is protected by copyright. All rights reserved.

Language: en