title: How to test brain and brain simulant at ballistic and blast strain rates.
abstract: Mechanical properties of brain tissue and brain simulant at strain rate in the range of 1000 s-1 are essential for computational simulation of intracranial responses for ballistic and blast traumatic brain injury. Testing these ultra-soft materials at high strain rates is a challenge to most conventional material testing methods. The current study developed a modified split Hopkinson bar techniques using the combination of a few improvements to conventional split Hopkinson bar including: using low impedance aluminum bar, semiconductor strain gauge, pulse shaping technique and annular specimen. Feasibility tests were conducted using a brain stimulant, Sylgard 527. Stress-strain curves of the simulant were successfully obtained at strain rates of 2600 and 2700 s-1 for strain levels up to 60%. This confirmed the applicability of Hopkinson bar for mechanical properties testing of brain tissue in the ballistic and blast domain.
authors.affiliation: Department of Neurosurgery, Medical College of Wisconsin, VA Medical Center, Milwaukee, WI, USA.
authors.forename: Jiangyue
authors.initials: J
authors.lastname: Zhang
authors.forename: Bo
authors.initials: B
authors.lastname: Song
authors.forename: Frank A
authors.initials: FA
authors.lastname: Pintar
authors.forename: Narayan
authors.initials: N
authors.lastname: Yoganandan
authors.forename: Weinong
authors.initials: W
authors.lastname: Chen
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Gennarelli