Department of Mechanical Engineering, The University of Texas at Dallas, Richardson, TX, 75080, USA; School of Aerospace and Mechanical Engineering, University of Oklahoma, Norman, OK, 73019, USA.
School of Aerospace and Mechanical Engineering, University of Oklahoma, Norman, OK, 73019, USA.
J Mech Behav Biomed Mater. 2019 Dec;100:103368. doi: 10.1016/j.jmbbm.2019.07.026. Epub 2019 Aug 7.
The rupture of the tympanic membrane (TM) is one of the major indicators for blast injuries due to the vulnerability of TM under exposure to blast overpressure. The mechanical properties of the human TM exhibit a significant change after it is exposed to such a high intensity blast. To date, the published data were obtained from measurement on TM strips cut from a TM following an exposure to blast overpressure. The dissection of a TM for preparation of strip samples can induce secondary damage to the TM and thus potentially lead to data not representative of the blast damage. In this paper, we conduct mechanical testing on the full TM in a human temporal bone. A bulging experiment on the entire TM is carried out on each sample prepared from a temporal bone following the exposure to blast three times at a pressure level slightly below the TM rupture threshold. Using a micro-fringe projection method, the volume displacement is obtained as a function of pressure, and their relationship is modeled in the finite element analysis to determine the mechanical properties of the post-blast human TMs, the results of which are compared with the control TMs without an exposure to the blast. It is found that Young's modulus of human TM decreases by approximately 20% after exposure to multiple blast waves. The results can be used in the human ear simulation models to assist the understanding of the effect of blast overpressure on hearing loss.
鼓膜（TM）破裂是爆震伤的主要指标之一，这是由于 TM 在暴露于爆炸超压下时很脆弱。人类 TM 的力学性能在暴露于如此高强度的爆炸后会发生显著变化。迄今为止，已发表的数据是通过测量暴露于爆炸超压后的 TM 条带获得的。为了准备条带样本而对 TM 进行解剖可能会对 TM 造成二次损伤，从而导致数据不能代表爆震损伤。在本文中，我们在人颞骨上对完整的 TM 进行了力学测试。对每个从颞骨准备的样本，在压力水平略低于 TM 破裂阈值的情况下，进行了三次爆炸暴露后的整个 TM 的鼓出实验。使用微条纹投影方法，将体积位移作为压力的函数获得，并在有限元分析中对其关系进行建模，以确定爆震后人类 TM 的力学性能，将结果与未暴露于爆震的对照 TM 进行比较。结果表明，人类 TM 的杨氏模量在多次暴露于爆震波后降低了约 20%。这些结果可用于人类耳朵模拟模型，以协助理解爆炸超压对听力损失的影响。
