老范这一次绝对翻车了:美国人的已有的测试目的不是提升轿车,而是提升卡车的防撞,哪怕是NHTSA的征求意见对应的不是轿车厂商而是semi truck的rear guard的司机厂商和IIHS 中国的标准[1]GB 11567-2017《汽车及挂车侧面和后下部防护要求》标准规定:对于最大设计总质量超过3500kg,但不超过12000kg的载货车辆和最大设计总质量超过750kg,但不超过3500kg的挂车,后下部防护装置截面高度不小于100 mm;对于最大设计总质量超过12000kg的载货车辆和最大设计总质量超过10000kg的挂车,后下部防护装置截面高度不小于120 mm。两点加载时,后下部防护装置应承受100kN的水平载荷。在按照B.1.1a)或b)进行试验时,左右两边外侧两个作用点,分别距离车辆后轴轮胎的最外端相切并且平行于车辆纵向中心线的垂直平面300mm±25mm 对比美国法规[2] S5.2.1 Guard Strength. The guard must resist the force levels specified in S5.2.1(a) through (c) of this section without deflecting by more than 125 mm and without eliminating any load path that existed before the test was initiated. (a) A force of 50,000 N applied in accordance with S6.6 of this section at test location P1 on either the left or the right side of the guard as defined in S6.4(a) of this section. (b) A force of 50,000 N applied in accordance with S6.6 of this section at test location P2 as defined in S6.4(b) of this section. (c) A uniform distributed force of at least 350,000 N applied across the horizontal member, as specified in S6.8 of this section and in accordance with S6.6 of this section.S5.2.2 Guard Energy Absorption.(a) A guard, other than a hydraulic guard or one installed on a tanker trailer, when subjected to a uniform distributed load applied in accordance with S6.6(c) of this section: (1) Shall absorb by plastic deformation at least 20,000 J of energy within the first 125 mm of deflection without eliminating any load path that existed before the test was initiated; (2) Have a ground clearance not exceeding 560 mm, measured at each support to which the horizontal member is attached, as shown in Figure 4 of this section, after completion of the load application. 对比了一下测试方法,外侧加载点和NHTSA FMVSS233是一样的(假设后防撞为L,NHTSA采用的离中轴线3/8L和我们规定的离外侧300mm没有本质区别:集装箱货柜的外侧宽度是固定的8ft give or take的一点) 所以,区别在哪?还是有的,美国多了1. deformation @ 125mm时候吸能20KJ 2. cross member loading 350kN其实美国人列出来最有趣的实际上是文件的而起草过程,中间甚至有关于是否需要增强到50kJ/100kJ@125mm和700kN测试的讨论[3]但是,必须要指出的是,IIHS对于这一重新立法修订上浮幅度太低不是很满意:他们认为P1位置需要重新讨论,吸能大小以及溃缩程度需要重新定义[4],也就是他们small overlap导致更多人死亡,但是NHSTA根据UoM的一个study作为反驳 个人认为与其去纠结中国汽车厂家,国家应该把更多的精力放在怎么去做卡车的防撞梁,毕竟国内哪怕17年的标准对应的也是美国人20年前的,人家已经翻篇了 [1] 竟然EU Commision有这一份文件的原版:www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&ved=2ahUKEwjR6qzR8MOJAxX6hP0HHVCPOUUQFnoECBEQAQ&url=https%3A%2F%2Fec.europa.eu%2Fgrowth%2Ftools-databases%2Ftbt%2Fen%2Fsearch%2F%3Ftbtaction%3Dget.project%26Country_ID%3DCHN%26num%3D1189%26dspLang%3DEN%26basdatedeb%3D%2C%26basdatefin%3D%26baspays%3DCHN%26baspays2%3DCHN%26basnotifnum%3D1189%26basnotifnum2%3D1189%26bastypepays%3DCHN%26baskeywords%3D%26project_type_num%3D1%26project_type_id%3D1%26lang_id%3DZH&usg=AOvVaw2X7MNXDQbdhadZDlqZ7Ylw&opi=89978449 [2] www.law.cornell.edu/cfr/text/49/571.223 [3] www.federalregister.gov/documents/2022/07/15/2022-14330/federal-motor-vehicle-safety-standards-rear-impact-guards-rear-impact-protection [4] www.iihs.org/news/detail/new-federal-rule-on-truck-underride-protection-does-not-go-far-enough