1.1 本试验方法包括用测量装置测量纵向摩擦系数，该测量装置在轮胎和表面之间施加制动滑移，用于制动滑移速度值的全范围。 1.2 当制动测试轮被拉过潮湿或受污染的路面时，该测试方法利用对制动测试轮上摩擦力的一系列增量单次测量。根据设定的程序参数，反馈控制制动轮的转速以给出预定的可变滑移比梯度。测试轮保持在恒定的静态法向载荷下和恒定的纵向行驶速度。其主平面垂直于道路平面，平行于其运动方向。 1.3 测量值代表用本试验方法中所述的设备和程序获得的摩擦特性，不一定与通过其他路面摩擦测量获得的值一致或直接相关g方法。 1.4 这些数值预期用于: 1.4.1 评估一个路面上相对于其他路面的制动摩擦力。 1.4.2 评估特定路面的制动摩擦力随时间的变化。 1.4.3 评估路面在受到抛光磨损和交通引起的宏观纹理损失时制动摩擦力随时间的变化。 1.4.4 评估被适量冰污染的路面制动摩擦力的变化 2 雪泥、花粉、车辆漏油和车辆发动机废气的冷凝物，以及其他污染源的沉积物。 1.4.5 评估样品轮胎在清洁或污染路面上的制动摩擦力。 1.5 该测试方法报告的摩擦值不足以确定在干燥、潮湿或受污染的路面上停车所需的距离。它们也不足以确定车辆失去控制的速度。 1.6 以SI单位或英寸-磅单位表示的值应单独视为标准值。每个系统中陈述的值可能不完全等同；因此，每个系统应独立使用。合并两个系统的值可能导致不符合标准。 1.7 本标准并不旨在解决与其使用相关的所有安全性问题（如果有）。本标准的使用者有责任在使用前建立适当的安全、健康和环境实践并确定法规限制的适用性。 第节给出了具体的预防声明 6 和 附注4 . 1.8 本国际标准是根据《关于制定国际标准的原则的决定》中确定的国际公认的标准化原则制定的世界贸易组织技术性贸易壁垒委员会发布的指南和建议。

1.1 This test method covers the measurement of the longitudinal friction coefficient with a measurement device that imposes braking slip between a tire and a surface for the full range of braking slip speed values. 1.2 This test method utilizes a series of incremental single measurements of friction force on a braked test wheel as it is pulled over a wetted or contaminated pavement surface. The rotational velocity of the braked wheel is feedback controlled in order to give a predetermined variable slip ratio gradient in accordance with set program parameters. The test wheel is kept under a constant static normal load and at a constant longitudinal speed of travel. Its major plane is perpendicular to the road plane and parallel to its direction of motion. 1.3 The values measured represent the friction properties obtained with the equipment and procedures stated in this test method and do not necessarily agree or correlate directly with those obtained by other pavement friction measuring methods. 1.4 The values are intended for use in: 1.4.1 Evaluating the braking friction forces on a pavement relative to that of other pavements. 1.4.2 Evaluating changes in the braking friction forces of a particular pavement with the passage of time. 1.4.3 Evaluating the changes in the braking friction force of a pavement when subjected to polishing wear and loss of macrotexture caused by traffic with passage of time. 1.4.4 Evaluating changes in the braking friction forces of a pavement contaminated with ice, moderate amounts 2 of slush and snow, pollen, vehicle oil spills and condensates from vehicle engine exhaust, and deposits from other pollution sources. 1.4.5 Evaluating the braking friction forces of a specimen tire on a clean or contaminated pavement. 1.5 The friction values reported by this test method are insufficient to determine the distance required to stop a vehicle on either a dry, wet, or contaminated pavement. They are also insufficient for determining the speed at which control of a vehicle would be lost. 1.6 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with the standard. 1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific precautionary statements are given in Section 6 and Note 4 . 1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.