年龄因素对行人下肢损伤的影响研究

Study on the Effect of Age on the Lower Extremity Injury of Pedestrians

在行人碰撞的事故中下肢是主要的受伤部位,为了提高对行人的保护,使用具有年龄差异性的行人下肢有限元模型来分析行人下肢损伤的不同。根据来源于中国交通事故深入研究(China in-depth accident study,CIDAS)数据库的真实的行人事故案例,利用PC-Crash软件进行事故重建,依据事故重建的输出参数,对车辆和行人下肢的有限元模型设置载荷和边界条件。通过模拟行人下肢与轿车模型的碰撞,比较年轻组和老年组的损伤差异,结果讨论膝关节的剪切位移、弯曲角度、以及韧带所承受的拉力和长骨的弯矩、剪切力等下肢损伤参数,并且进一步通过逻辑回归的方法分析这些损伤参数与下肢AIS3+严重损伤的相关性,最后得到年轻组和老年组的严重损伤风险曲线。其结果显示年轻组和老年组损伤风险存在差异性,当AIS3+严重损伤概率为50%时,得出年轻组和老年组的长骨和膝关节的损伤阈值及耐受极限。研究的结果可为具有年龄差异的行人下肢损伤评估指标的设定提供参考。

In the accident of pedestrian collision,the lower limb is the main injured part.In order to improve the protection of pedestrians,the finite element model of pedestrian lower limbs with age difference is used to analyze the difference of pedestrian lower limb injury.According to the real pedestrian accident case from the China in-depth accident study(CIDAS)database,the PC-Crash software was used to reconstruct the accident,and the load and boundary conditions were set for the finite element model of the vehicle and pedestrian lower limb based on the output parameters of the accident reconstruction.By simulating the collision between the lower limbs and the sedan model,the differences between the young and the old groups were compared.The results discussed the shear displacement,bending angle,and the tensile force of the ligament and the bending moment and shear force of the long bone and further correlations between these injury parameters and severe AIS3+injury were analyzed by logistic regression.Finally,the severe injury risk curves of young and old groups were obtained.The results showed that there was a difference in the risk of injury between the young group and the elderly group.When the probability of severe injury of AIS3+was 50%,the damage threshold and tolerance limit of the long bone and kNee joint of the young group and the old group were obtained.The results of the study can provide a reference for the setting of age-related pedestrian lower limb injury assessment indicators.