跌落工况下的人体腰椎损伤风险的几种影响因素

Factors for affecting risk of human lumbar spine injuries under dropping conditions

在车辆正面碰撞事故、军事车辆底部爆炸、使用弹射座椅时,因轴向冲击而造成的腰椎损伤多有发生,从而导致行动不便甚至截瘫。本文使用有限元方法对Hybrid-III型50百分位男性假人的跌落工况进行了多组数字模拟,针对冲击速度、地面角度、坐垫厚度、摩擦因数等4种腰椎损伤影响因素,进行了敏感性分析。结果显示:冲击速度与坐垫厚度对腰椎损伤具有显著影响,而其他因素影响不够显著。冲击速度增大,腰椎损伤风险增大;坐垫厚度增大,腰椎损伤风险减小:跌落的冲击速度在6 m/s及以上,或坐垫厚度在100 mm及以下时,腰椎会有骨折的风险。该研究结果,可用于轴向力造成事故中腰椎损伤保护措施的结构设计和改善;例如增加坐垫厚度、减小接触摩擦、增大冲击角度。

Lumbar injuries caused by axial impact often occur in frontal crash, the explosion of military vehicles at the bottom and pilot ejection, which lead to paraplegia. Finite element method was used in simulation of dropping conditions with Hybrid III 50 th Dummy model. Four factors affecting human lumbar spine injuries were put forward including impact velocity, ground angle, cushion thickness and friction coefficient with analyzing the sensitivity of each factor the four. The results show that the impact velocity and the cushion thickness have great influence on lumbar injuries, and other factors are not significant. The lumbar injury risk increases with impact velocity increase and decreases with cushion thickness increase. Lumbar has a risk of fracture when the impact velocity is 6 m/s and above, or the cushion thickness is 100 mm and below. These results can help to improve the protection of lumbar which injured by axial force in the accident. For example, increase the cushion thickness, reduce contact friction and increase impact angle.