ASTM F1649-20
Standard Test Methods for Evaluating Wet Braking Traction Performance of Passenger Car Tires on Vehicles Equipped with Anti-Lock Braking Systems

Standard No.

ASTM F1649-20

Release Date

2020

Published By

American Society for Testing and Materials (ASTM)

Latest

ASTM F1649-20

Scope

1.1 These test methods cover the measurement of two types of ABS vehicle behavior that reflect differences in tire wet traction performance when the vehicle is fitted with a series of different tire sets to be evaluated. 1.1.1 The stopping distance from some selected speed at which the brakes are applied. 1.1.2 The lack of control of the vehicle during the braking maneuver. Uncontrollability occurs when the vehicle does not follow the intended trajectory during the period of brake application despite a conscious effort on the part of a skilled driver to maintain trajectory control. Uncontrollability is measured by a series of parameters related to this deviation from the intended trajectory and the motions that the vehicle makes during the stopping maneuver. 1.1.3 Although anti-lock braking systems maintain wheel rotation and allow for a high degree of trajectory control, different sets of tires with variations in construction, tread pattern, and tread compound may influence the degree of trajectory control in addition to stopping distance. Thus vehicle uncontrollability is an important evaluation parameter for tire wet traction performance. 1.2 These test methods specify that the wet braking traction tests be conducted on two specially prepared test courses: (1) a straight-line (rectilinear) “split-µ” (µ = friction coefficient) test course, with two test lanes deployed along the test course (as traveled by the test vehicle); the two lanes have substantially different friction levels such that the left pair of wheels travels on one surface while the right pair of wheels travels on the other surface; and (2) a curved trajectory constant path radius course with uniform pavement for both wheel lanes. 1.3 As with all traction testing where vehicle uncontrollability is a likely outcome, sufficient precautions shall be taken to protect the driver, the vehicle, and the test site facilities from damage due to vehicle traction breakaway during testing. Standard precautions are roll-bars, secure mounting of all internal instrumentation, driver helmet, and secure seat belt harness, etc. 1.4 The values stated in SI units are to be regarded as the standard. The values given in parenthesis are for information only. 1 These test methods are under the jurisdiction of ASTM Committee F09 on Tires and is the direct responsibility of Subcommittee F09.20 on Vehicular Testing. Current edition approved Oct. 1, 2020. Published October 2020. Originally approved in 1995. Last previous edition approved in 2013 as F1649 – 13. DOI: 10.1520/F1649-20. Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States 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. 1.5 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. 1.6 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.

ASTM F1649-20 Referenced Document

• ASTM E1136 Standard Specification for A Radial Standard Reference Test Tire
• ASTM E1337 Standard Test Method for Determining Longitudinal Peak Braking Coefficient of Paved Surfaces Using Standard Reference Test Tire
• ASTM E274 Standard Test Method for Skid Resistance of Paved Surfaces Using a Full-Scale Tire
• ASTM E303 Standard Test Method for Measuring Surface Frictional Properties Using the British Pendulum Tester
• ASTM E501 Standard Specification for Standard Rib Tire for Pavement Skid-Resistance Tests
• ASTM E524 Standard Specification for Standard Smooth Tire for Pavement Skid-Resistance Tests
• ASTM E965 Standard Test Method for Measuring Pavement Macrotexture Depth Using a Volumetric Technique
• ASTM F1046 Standard Guide for Preparing Artificially Worn Passenger and Light Truck Tires for Testing
• ASTM F1572 Standard Test Methods for Tire Performance Testing on Snow and Ice Surfaces
• ASTM F1650 Standard Practice for Evaluating Tire Traction Performance Data Under Varying Test Conditions
• ASTM F1805 Standard Test Method for Single Wheel Driving Traction in a Straight Line on Snow- and Ice-Covered Surfaces
• ASTM F1806 Standard Practice for Tire Testing Operations-Basic Concepts and Terminology for Reference Tire Use
• ASTM F2493 Standard Specification for P225/60R16 97S Radial Standard Reference Test Tire*， 2023-09-01 Update
• ASTM F457 Standard Test Method for Speed and Distance Calibration of a Fifth Wheel Equipped With Either Analog or Digital Instrumentation
• ASTM F538 Standard Terminology Relating to the Characteristics and Performance of Tires

ASTM F1649-20 history

• 2020 ASTM F1649-20 Standard Test Methods for Evaluating Wet Braking Traction Performance of Passenger Car Tires on Vehicles Equipped with Anti-Lock Braking Systems
• 2013 ASTM F1649-13 Standard Test Methods for Evaluating Wet Braking Traction Performance of Passenger Car Tires on Vehicles Equipped with Anti-Lock Braking Systems
• 1996 ASTM F1649-96(2003) Standard Test Methods for Evaluating Wet Braking Traction Performance of Passenger Car Tires on Vehicles Equipped with Anti-Lock Braking Systems
• 1996 ASTM F1649-96e1 Standard Test Methods for Evaluating Wet Braking Traction Performance of Passenger Car Tires on Vehicles Equipped with Anti-Lock Braking Systems