面向低龄儿童头部碰撞防护的小型猪颅骨损伤特性和破裂限值研究

Among all types of children’s injuries caused by impact, head injury, especially skull fracture is the leading cause of pediatric disability and fatality. Due to ethical reasons, very limited pediatric cadaver tests and low biofidelity of child test dummies discourage the study on the pediatric skull injury. The existing skull fracture thresholds developed through scale method or accident reconstruction by child dummy and finite element model have been proved to be contradicted with available results of cadaver tests. Due to the inherent constraints by limited number of pediatric cadaver tests, using animal surrogates to study the skull injury characteristic is an indirect, but effective method. In this proposal, the following studies will be planned to conduct using the piglets aged 0-3 months old (approximately equivalent to 0-4 years old children). (1) The mechanical property tests at multiple strain rates and the head global impact tests under different loadings for piglet will be respectively performed. (2) A group of finite element models that can represent the variation of piglet skull morphologies with age will be developed. (3) We will also put forward a dynamic theoretical model that can take the piglet skull morphological features into consideration. Combined with the aforementioned results, the piglet skull injury characteristics affected by ages and loading conditions will be investigated, and the skull fracture threshold will be further established for piglets with different ages. The aim of this proposal is to explore new ideas for studying pediatric skull injury. The results of this study are beneficial for clarifying pediatric skull injury.

头部伤害，特别是颅骨破裂是碰撞中儿童伤亡的主要原因。由于道德、伦理原因造成的试验数据稀缺和儿童假人生物逼真度低使得目前在颅骨损伤研究方面进展缓慢。几个通过使用有限元模型或儿童假人对事故进行再现或采用缩放方法建立的颅骨破裂限值多被证明与现有试验结果相悖。在缺乏儿童头部生物力学数据现状下，通过使用小型动物从更基础层次研究颅骨损伤及破裂限值是一种间接但有效的方法。本项目以0-3个月小型猪（大约为0-4岁儿童）头部为研究对象，（1）进行多应变率小型猪头部材料力学属性和多工况头部碰撞试验；（2）创新性的建立形态特征和材料对应的小型猪有限元模型群；（3）构建考虑小型猪头盖骨形态特征的碰撞动力学理论模型。最终，综合试验、仿真、理论的研究，揭示小型猪年龄、碰撞工况对颅骨损伤特性的影响规律，并建立不同年龄小型猪颅骨破裂限值。本项目旨在发展儿童颅骨损伤研究新思路，研究对阐明儿童颅骨损伤特性具有很好借鉴价值。

儿童颅骨破裂是碰撞中儿童伤亡的主要原因。由于道德、伦理原因造成的试验数据稀缺和儿童假人生物逼真度低使得目前在儿童颅骨损伤研究方面进展缓慢。在缺乏儿童头部生物力学数据现状下，通过使用小型动物从更基础层次研究颅骨损伤及破裂限值非常有必要。本项目以0-3个月小型猪头部为研究对象，通过研究得出了（1）0-3个月小型猪，尤其是2个月小型猪颅骨、脑部等组织在多个应变率下的力学试验结果，建立了小型猪头部材料属性数据库，确定了能够表征不同组织力学行为的本构模型。（2）建立了基于解剖学的小型猪头部有限元模型并进行了试验验证，在此基础上，将该模型变换得到不同年龄节点的模型，该类模型可以用于颅骨破裂的预测。（3）建立了虑碰撞点曲率和不均匀颅骨厚度的小型猪和儿童头部的碰撞接触动力学理论模型并进行试验验证，该模型可以快速预测头部在不同冲击速度下的宏观响应。（4）综合试验、仿真和理论结果建立了0-3 个月多个年龄节点的小型猪颅骨破裂限值。本项目取得的重要结果和关键数据可以为儿童头部的防护提供很好的借鉴和参考，对阐明儿童颅骨损伤特性具有很好借鉴价值。