不同载荷作用下头部生物力学响应仿真分析

目的建立符合解剖结构的人颅骨三维有限元模型,研究多种载荷作用下头部生物力学响应。方法通过建立具有解剖结构的高精度头部有限元模型,颅骨采用能模拟骨折的弹塑性材料本构模型,结合已发表的正面冲击颅内压实验、动态颅骨骨折实验、头部跌落实验结果,仿真再现实验过程中头部受冲击载荷作用下的生物力学响应、颅骨骨折及头部不同速度下的跌落响应。结果前碰撞表现出冲击与对冲侧正-负颅内压分布,相近载荷下枕骨变形比前额、顶骨严重,跌落中速度越快损伤越大。结论建立精确解剖结构的头部有限元模型可以较好模拟头部在冲击、跌落等载荷下的生物力学响应。通过量化接触力、颅内压力等参数来评价头部损伤风险,为防护系统的设计提供科学依据。

The simulation analysis on biomechanical responses of human head under different loading conditions

Objective To construct a three-dimensional finite element model of human skull with anatomic structure and to study biomechanical responses of the head under various loading conditions. Methods The finite element model of high-precision human head with anatomic structure was reconstructed with the constitutive skull made from elastic-plastic material to simulate the fracture. This model was used to simulate frontal impact intracranial pressure testing, dynamic skull fracture testing and head drop testing reported by the literature, and the simulation reproduced the experimental process of head subjected to impact loads, skull fractures, and biomechanical responses of head fall at different speed. Results Under frontal impact loading, the model showed hedge-side positive-negative intracranial pressure distributions, and the occipital deformation was more serious than that in prefrontal, parietal under similar loading. The faster falling speed would cause more serious injuries. Conclusions To establish the accurate anatomic finite element model of human head can preferably simulate biomechanical responses of the head under the loading of impact and fall. Through quantifying parameters such as contact force and intracranial pressure, injury risks can be assessed to provide scientific references for design of protective devices.