【作者】 张帆；

【导师】 王成彪； 周青；

【作者基本信息】 中国地质大学（北京） ， 机械设计及理论， 2006， 硕士

【摘要】 全国每年因道路交通事故而死亡的人数大体在11万人左右,约有1/3的死亡事故发生在车辆与路侧护栏的单车事故中,造成的人员伤亡和财产损失严重影响国家生产安全。因而,对车辆与护栏碰撞的研究将具有极其重要的现实意义。通过归纳EN1317与NCHRP Report 350两种护栏安全防护性能评估规范中的具体内容,对试验车辆的选择、护栏等级的划分、防护性能的评估指标以及试验执行的方法做了比较全面的分析与比较。当我国建立自己的评价规范时,建议试验车辆应该要通过大量统计采用最能够代表本国道路中主流的车型。护栏防护等级要针对不同车型并根据我国国情的事故特点而制定。对乘员损伤的评价方法上需要尝试应用最新的设备与技术,但评价指标仍建议采用国外现有指标。通过车辆与护栏碰撞的碰撞仿真模拟过程,首次成功建立了大型客车在道路安全评估方面的有效模型。与一般的车辆碰撞发生在0.1秒内不同,车辆与护栏的碰撞要求模拟时间持续1秒以上甚至更长。大型客车在建模过程中不但权衡了模型精度和运算时间的关系,并且为得到更好的碰撞响应,建立出了客车的悬架、转向和充气轮胎模块。最终碰撞模拟结果与实验记录在客车的局部变形与行驶轨迹方面都有着很好的比对关系。此大型客车建模验证的方法为今后使用LS-DYNA建立其它用于护栏性能评估的车辆模型提供依据。最后提出把侧撞试验用的移动可变形壁障(MDB)经过某种改进移植到护栏评估试验中替代实车的设想。认为MDB参数需要按照规范中的质量、重心位置与车身尺寸进行设定, MDB碰撞区域需要安装可变形材料。可变形材料的刚度特性的确定在试验方法与材料选择上都遇到难点。继续开发适用于护栏性能评估的MDB为今后评估护栏的试验方法提出了新思路。更多还原

【Abstract】 Over 110 thousands people caused by traffic accidents die annually. About one third offatal accidents are single-vehicle accidents involving the impact between vehicles androadside guardrails. The loss of the injury and treasure affects the safety of nationalproduce. As a result, the research of the impact between vehicles and guardrails hasmany realistic meaning. Summarized are the contents of two criteria about the safetyperformance evaluation of guardrails, EN1317 and NCRHP Report 350. Those areanalyzed and compared between two criteria including vehicle selections, guardrailprotecting levels, safety performance evaluation indexes and test methods. Whencriteria are founded in china, it should be considered that the test vehicle model mustrepresent the mainstream in the traffic road by statistical methods. Guardrailprotecting levels are ranked according with the different features of the real cases.New equipments and technologies should be attempted to apply into the evaluationsof the occupant injury indexes. But the evaluating index can be adopted as the foreigncriteria. For the evaluation of the guardrails using simulation technology, the finiteelement bus model is successfully built. Unlike a car crash test that typically lastsabout 0.1 seconds, the vehicle-guardrail crash test needs to be monitored for one secondor longer. This is a great challenge to the bus modeling in terms of balancing thestructural details and computational efficiency. To better capture the impact response,the bus suspension, the tire rotation, the steering, and the tire pressure are alsomodeled. The simulation correlates well with the test results in the local deformationof the bus, and more importantly, in the post-impact trajectory of the bus. Theprocessing of the validating methods is a sample using LS-DYNA to simulate theguardrail impacts. Moving Deformable Barrier (MDB) substituted the full vehicle canbe adopted in the test. The parameters of the MDB are set including with its mass, thecenter of gravity and dimensions as the criteria demanded. Deformable material isfitted in the crash zone of the MDB. There are some difficulties in measuring thematerial stiffness and selecting the material with the proper characters. Developmentof the MDB using in the safety performance evaluation will be the new method in theevaluation test.更多还原