Abstract
Detonation of a high-explosive produces shock-blast wave, shrapnel, and gaseous products. While direct exposure to blast is a concern near the epicenter, shock-blast can affect subjects, even at farther distances. When a pure shock-blast wave encounters the subject, in the absence of shrapnels, fall, or gaseous products the loading is termed as primary blast loading and is the subject of this paper. The wave profile is characterized by blast overpressure, positive time duration, and impulse and called herein as shock-blast wave parameters (SWPs). These parameters in turn are uniquely determined by the strength of high explosive and the distance of the human subjects from the epicenter. The shape and magnitude of the profile determine the severity of injury to the subjects. As shown in some of our recent works (1–3), the profile not only determines the survival of the subjects (e.g., animals) but also the acute and chronic biomechanical injuries along with the following bio-chemical sequelae. It is extremely important to carefully design and operate the shock tube to produce field-relevant SWPs. Furthermore, it is vital to identify and eliminate the artifacts that are inadvertently introduced in the shock-blast profile that may affect the results. In this work, we examine the relationship between shock tube adjustable parameters (SAPs) and SWPs that can be used to control the blast profile; the results can be easily applied to many of the laboratory shock tubes. Further, replication of shock profile (magnitude and shape) can be related to field explosions and can be a standard in comparing results across different laboratories. Forty experiments are carried out by judiciously varying SAPs such as membrane thickness, breech length (66.68–1209.68 mm), measurement location, and type of driver gas (nitrogen, helium). The effects SAPs have on the resulting shock-blast profiles are shown. Also, the shock-blast profiles of a TNT explosion from ConWep software is compared with the profiles obtained from the shock tube. To conclude, our experimental results demonstrate that a compressed-gas shock tube when designed and operated carefully can replicate the blast time profiles of field explosions accurately. Such a faithful replication is an essential first step when studying the effects of blast induced neurotrauma using animal models.
Highlights
In the study of blast induced neurotrauma (BINT) using animal models, many research groups use compressed-gas-driven shock tubes to simulate primary blast injury conditions [4,5,6,7,8,9]
BURST PRESSURE Burst pressure is the pressure in the driver section at the time of the membrane rupture. This highly compressed gas when allowed to expand rapidly compresses the atmospheric air in the transition and driven sections generating a shock front
There is no discernible difference in the burst pressure with respect to increase in breech length for any of the three membrane thicknesses studied
Summary
In the study of blast induced neurotrauma (BINT) using animal models, many research groups use compressed-gas-driven shock tubes to simulate primary blast injury conditions [4,5,6,7,8,9]. Numerous cases of soldier injuries in operation Iraqi freedom (OIF) and operation enduring freedom (OEF) were directly attributed to the blasts, resulting from improvised explosive devices (IEDs) used by the insurgents. Among these injuries, the most common was the traumatic brain injury, which is the signature injury of these conflicts [12,13,14,15]. The mild TBI is classified as loss of consciousness for
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
