枪弹冲击下头-颈动力学响应及颈部被动肌影响

针对战场环境下弹体、破片的威胁，研究枪弹冲击下头-颈动力学响应及颈部被动肌影响。利用已建立并通过验证的头盔-头-颈有限元模型，开展9 mm手枪弹冲击数值模拟，获得有/无被动肌作用下人体头-颈动力学响应。研究结果表明：正面冲击时，首先头部额骨处产生应力集中，随后颈部后伸，颈部应力主要集中于下颈椎椎体，椎间盘前侧产生拉伸失效；在被动肌作用下，头部质心最大位移减少31.38%，颈椎椎骨与椎间盘连接处应力以及椎间盘最大应力均降低，椎间盘最大应力减少28.76%；颈部被动肌起到重要的保护作用，可缓解头-颈后伸，减轻颈椎的损伤，在颈部损伤评估中应考虑被动肌的影响。该研究结果可为颈部损伤评估和颈部防护装备的设计提供参考。

Dynamic Head-Neck Response to Bullet Impact and Effects of Passive Muscles on the Neck

To address the threat of projectiles and fragments in a battlefield, head-neck dynamic response to bullet impact and the effects of passive neck muscles are studied. By establishing an effective helmet-head-neck finite element model, the impact of 9 mm handgun bullets is simulated to examine the human head-neck mechanical response with or without passive muscles. The results show that in the case of front impact, stress is concentrated on the frontal head bone and the lower cervical vertebrae when the neck is extended. When the front side of the intervertebral disc fails to stretch, the passive muscles on the neck relieve the extension of the head and neck, reducing the cervical spine injury. Under the effect of passive muscles, the displacement of the head's centroid is reduced by 31.38%, and the stress exerted on the junction between cervical vertebrae and intervertebral disc as well as the maximum intervertebral disc stress are relieved by 28.76%. Thus, passive muscles play an important role in protecting the body, and thus must be considered when assessing neck injuries. The results provide reference for the assessment of neck injuries and the design of neck protective equipment.