基于行人碰撞事故重建的颅脑损伤准则效能研究

Investigation of Prediction Effectiveness of Brain Injury Criteria on Injury Risk Through Reconstruction of Pedestrian Impact Accidents

为了深入研究不同颅脑损伤准则对道路交通事故中行人颅脑损伤的预测与评价性能,从已有的交通事故调查数据库中选出可以用于进行事故虚拟重建且具有详细人体颅脑伤情记录的10例行人车辆碰撞事故案例,采用多刚体动力学和有限元分析方法,对事故中人和车辆运动学响应及行人颅脑损伤情况进行虚拟重建,在此基础上,采用LASSO回归分析方法分析了多个基于人体头部运动学响应的颅脑损伤准则与事故中行人颅脑损伤的相关性;借助文献中的损伤风险曲线,分析了不同基于脑组织应变的损伤准则与行人典型颅脑损伤(弥散性轴索损伤和脑挫伤)之间的关系。研究结果表明:在多个基于人体头部运动学响应的颅脑损伤评价准则中,同时考虑头部线性和旋转运动,且体现头部碰撞功率的头部碰撞能量(HIP)准则能最有效地评价真实的颅脑损伤;基于脑组织应变的颅脑损伤准则中,累计应变损伤测量(CSDM)准则相对于最大主应变(MPS)准则能更有效地评价典型弥散性脑损伤(DAI),而扩张损伤测量(DDM)准则所反映的脑挫伤程度远低于真实的损伤状况,所以该准则难以准确预测脑挫伤的损伤风险。

To comprehensively explore the effectiveness of the various brain injury criteria, by the prediction and evaluation of pedestrian brain injuries involved in road traffic accidents, 10 real- world car-to-pedestrian impact accident cases that could be virtually reconstructed with detailed brain injury data were selected from a vehicle traffic accident database. The kinematics of the vehicles and pedestrians as well as the pedestrian brain injuries involved in the selected accident cases were constructed by means of the multibody and finite element methods, respectively. The correlations of several existing kinematics-based brain injury criteria with the pedestrian brain injuries observed in the accident cases were determined through the LASSO regression analysis method. The relationship between various strain-based brain injury criteria and two major types of brain injury （diffuse axonal injury DAI and brain contusions） was analyzed using injury risk curves recorded in the literature. The results indicate that the impact-power-based criterion, i. e. , head impact power （HIP）, which considers both the head translational and rotational motions, has a better correlation with the pedestrian brain injuries than the other kinematics- based injury criteria. The results also tend to suggest that the cumulative strain damage measure （CSDM） criterion is a better predictor for the DAI than the maximum principal strain （MPS） criterion; further, dilatation damage measure （DDM） presents a very low risk for brain contusions, which means that the DDM could not accurately predict brain contusions.