00000nam 2200000za 4500 9.853766 CaOODSP 20240221113057 cr ||||||||||| 180316s2017 quca fo f000 0 eng d CaOODSP eng n-cn--- D69-52/2017E-PDF Ouellet, Simon, 1981- The multi-modal responses of a physical head model subjected to various blast exposure conditions [electronic resource] / Simon Ouellet and Mat Philippens. [Valcartier, QC] : Defence Research and Development Canada, c2017. 1 v. : col. ill. External literature (P) ; DRDC-RRDC-2017-P104 Published in: Springer, Journal of Shock Waves, November 2017. "November 2017." Includes bibliographic references. This article presents the joint analysis of previous blast test results generated with the brain injury protection evaluation device (BIPED) headform under four significantly different exposure conditions. The focus of the analysis is to demonstrate how the nature of the recorded response is highly dependent on the exposure characteristics and consequently, on the method used to reproduce blast exposure in a laboratory environment. The timing and magnitude of the variations in intra-cranial pressures (ICP) were analysed relative to the external pressure field in order to better understand the wave dynamics occurring within the brain structure of the headform. ICP waveforms were also analysed in terms of their energy spectral density to better identify the energy partitioning between the different modes of response. It is shown that the BIPED response is multi-modal and that the energy partitioning between its different modes of response is greatly influenced by exposure characteristics such as external peak overpressure, impulse, blast wave structure, and direction of propagation. Convincing evidence of stresses generated from local skull deformation is presented along with evidence of stress transmission through relative brain-to-skull motion. These findings suggest that research aimed at defining exposure thresholds should not focus on a single stress transmission mechanism or use experimental designs unrepresentative of realistic blast loading conditions that may favour a given mechanism over another. gccst Injuries gccst Explosions Blast neuro-trauma Headform Head biomechanics Injury mechanisms Intra-cranial pressure Philippens, Mat. Defence R&D Canada. Valcartier Research Centre. External literature (P) (Defence R&D Canada) DRDC-RRDC-2017-P104 (CaOODSP)9.854437 PDF 3.63 MB https://publications.gc.ca/collections/collection_2018/rddc-drdc/D69-52-2017-eng.pdf