中国人体小腿冲击仿真分析与损伤准则的研究

A Study on the Simulation Analysis and Injury Criterion of Chinese Lower Leg Impact

在已开发的中国人体50百分位男性小腿有限元模型的基础上,加入脚部模型和与踝关节动力学特性相关的11条踝关节韧带和11束肌肉有限元模型,以进行踝关节动力学特性的研究和肌肉主动力的模拟。采用单点积分壳单元模拟踝关节韧带,其余韧带采用梁单元模拟。基于乘员小腿的碰撞损伤载荷特点,采用两种小腿轴向冲击试验,对小腿模型进行了验证。结果显示,小腿轴向冲击动力学特性曲线与试验吻合较好,说明模型具有较高的生物逼真度。在此基础上,利用模型,对胫骨指数(TI)与修正胫骨指数(RTI)的损伤预测能力进行评估,对比了中国人体与欧美人体的差异。结果表明,尽管RTI改善了小腿的骨折损伤的预测能力,但对于中国50百分位男性小腿,RTI仍然低估了其损伤程度,需进行相应修正。

Based on the Chinese 50 th percentile male lower-leg model developed,the foot model,the model for 11 ankle ligaments and the model for 11 bundles of muscle are added to be used for conducting the study on ankle dynamics characteristics and the simulation on active force. The single-point integration shell element is used to simulate the ankle ligaments and the other ligaments are simulated by beam element. The lower leg model is then validated by two axial impact tests based on the collision injury loading characteristics of occupant＇s lower leg. The results show that the dynamic response curves for the axial impact of lower leg agree well with test data,demonstrating the high bio-fidelity of the model. On this basis,the model is used to evaluate the injury prediction ability of Tibia Index（ TI） and Revised Tibia Index（ RTI）,and to compare the human body differences between Chinese and the Occident（ European and American）. The results indicate that though RTI improves the predictive ability of tibia fracture injuries,but still underestimates the injury severity of the 50 th percentile Chinese male lower leg,needing corresponding further revisions.