基于塑性材料“变形与撞击能量”的肝脏损伤评估方法研究

The liver is the organ getting damage easily and one of deadly factors in road traffic injuries. The assessment of liver damage is the necessary foundation for vehicle safety design and mortality reduction. Now, there is an assessment method relying on crash dummy, but it's a highly simplified model, therefore, it is difficult to assess liver damage. An ideal assessment method of liver damage has been seeking in research. A liver model of plastic polymer material is planned to be constructed in this project, then the appearance, mode of action and energy of injury-induced object can be perceived through the model deformation, so as to objectively assess severity of liver damage. Based on the previous animal experiment and research on the liver physical model in this group, further screening the components of the material and technological conditions, establishing constitutive equation, and carrying out the research on computer analog simulation of liver damage; carrying out the research on crash experiment of biological and plastic viscera prosthesis based on the injury-induced platform and large testing equipment in the vehicle/biological collision security key laboratory, and discussing the concentration-response relationship of liver model deformation-deformation way- - injury-induced energy-damage degree; at last, achieving typical traffic crash cases and personnel injury details through Bayi judicial authentication center for traffic crash in Chongqing, and verifying the liver physical model. The problem of objective assessment of human body and visceral injury could be solved on this basis.

肝脏是道路交通伤中易受损器官并引起死亡的主因之一。对肝脏损伤的评估是车辆安全设计和降低伤亡率的必要基础。现有评估方法依赖于碰撞假人，因其是一高度简化模型，难以评估肝脏损伤。研究一直在寻求一种理想的肝脏损伤评估方法。本项目拟通过构建塑性高分子材料肝脏模型，通过模型变形来感知致伤物外形、作用方式和致伤能量等，从而客观评估肝脏损伤的严重度。以本课题组前期动物实验和肝脏物理模型研究为基础，进一步筛选材料的组分及制备条件，建立本构方程，开展肝脏损伤的计算机模拟仿真研究；并依托车辆/生物碰撞安全重点实验室的致伤平台和大型检测设备开展生物和可塑性脏器假体的碰撞实验研究，探讨肝脏模型变形量-变形方式- - 致伤能量-损伤程度之间的量效关系；最后通过重庆市八益交通事故司法鉴定中心获取典型交通事故案例和人员损伤细节，验证肝脏物理模型。，在此基础上可望解决人体及其脏器损伤的客观评估难题。

肝脏是道路交通伤中易受损器官并引起死亡的主因之一。对肝脏损伤的评估是车辆安全设计和降低伤亡率的必要基础。现有评估方法依赖于碰撞假人，因其是一高度简化模型，难以评估肝脏损伤。为此，本项目通过构建塑性复合材料肝脏物理模型，从而客观评估肝脏损伤的严重度。本课题建立了一种全新的肝脏损伤的评估方法，通过研制新型塑性复合材料并制成肝脏物理模型，建立了准确的塑性复合材料数字模型，通过仿真和实验建立塑性复合材料变形量与撞击能量的量效关系，进而从体积变形量获得准确的撞击能量；兔和猪肝脏正面撞击“减速性损伤”实验研究结果显示：在撞击减速度达到35.0km/h时，同时减速度峰值超过22g(g为重力加速度)，肝脏出现损伤，此时只有约10%的撞击能量到达肝脏，人肝脏总质量介于兔和猪之间，胸壁和腹壁厚度同样处于两者之间，因此人肝脏出现损伤的条件应该相似；THUMS4.0人体有限元模型研究不同车速下100%正面碰撞中驾驶员肝脏损伤对应的等效应变，在碰撞速度为30～50km/h时，应变在肝脏背侧中部最大，最大随碰撞速度增加，主应变逐渐增加，35km/h时达到72.84%；通过重庆市八益交通事故司法鉴定中心共采集了20例涉及腹腔脏器损伤的行人交通事故案例中发现，出现肝脏损伤的案例平均速度为45.33km/h；由于现有案例的数量限制，还无法较准确的推断出肝脏出现损伤时的准确能量，仍需进一步研究。本项目提供一种较为可靠的肝脏损伤方法，为驾乘人员肝脏损伤的力学评估和防护提供了理论依据。