Abstract

Rollover crashes have the highest fatality rate and exhibit complex and unpredictable mechanisms in terms of vehicle-ground and vehicle-occupant interactions. The objective of this study is to evaluate the tilt table and modified dolly rollover (MDR) crash tests in terms of how these crash tests can represent those interactions and compare their results with two real-world rollover crashes. An application of combined dynamic and finite element (FE) simulations was presented to assess the cutaway bus rollover crash. First, the numerical models were validated against the experimental MDR test. Then, two real-world rollover crashes were simulated in PC-Crash to find the kinematics of the bus prior to the first vehicle-to-roof impact phase. Next, the impact phase of these real-world crashes was simulated using LS-DYNA and the results were compared with the two rollover crash tests. The FE simulations were conducted using a 2-point belted 50th Hybrid III FE model. The results of this study indicate that the common impact mechanism among these rollover scenarios was the impact between the bus’s roof corner (roof connection to the sidewall) and ground which caused lateral deformation patterns. Furthermore, unlike passenger cars where the vertical roof deformation can cause severe injuries in rollover crashes, the intrusion of the bus’s passenger compartment was not identified as a main source of injury. In addition, the highest head, neck, and chest injury risk were predicted during the MDR simulation where the ATD was partially ejected through the side window. Lastly, possible future works and limitations were explained.

摘要

翻车事故的致死率最高，并且在车辆与地面和车辆与乘员的相互作用方面表现出复杂且不可预测的机制。本研究的目的是评估倾斜台和改进的小车侧翻 (MDR) 碰撞测试，了解这些碰撞测试如何代表这些相互作用，并将它们的结果与两个真实世界的翻车碰撞进行比较。提出了一种组合动态和有限元 (FE) 模拟的应用，用于评估切面公共汽车翻车事故。首先，数值模型针对实验 MDR 测试进行了验证。然后，在 PC-Crash 中模拟了两次真实世界的翻车事故，以找出公共汽车在第一个车顶碰撞阶段之前的运动学。下一个，使用 LS-DYNA 模拟了这些真实世界碰撞的冲击阶段，并将结果与​​两次翻车碰撞测试进行了比较。有限元模拟是使用 2 点带第 50 次混合 III 有限元模型进行的。这项研究的结果表明，这些侧翻情景中常见的冲击机制是公共汽车的车顶角（车顶与侧壁的连接）与地面之间的碰撞，从而导致横向变形模式。此外，与垂直车顶变形会在翻车事故中造成严重伤害的乘用车不同，公共汽车乘客舱的侵入未被确定为主要伤害源。此外，在 MDR 模拟期间预测了最高的头部、颈部和胸部受伤风险，其中 ATD 部分通过侧窗弹出。最后，