ASTM F1016-07(2020)

Standard Practice for Linear Tire Treadwear Data Analysis

SIGNIFICANCE AND USE
5.1 The purpose of this practice is to standardize the meaning and derivation of some terms and indexes that are commonly used to characterize treadwear.  
5.1.1 There is no intent to recommend either of the two treadwear performance indexes: distance per unit loss of tread depth or loss of tread depth per distance unit.
SCOPE
1.1 This practice describes the elementary linear regression analysis of basic treadwear data as obtained according to Test Method F421 and Test Method F762.  
1.2 The basic treadwear data are obtained as groove depth loss measurements by procedures described in Test Method F421 after a series of test cycles (test distances under specified conditions) according to Test Method F762.  
1.3 A linear regression analysis is performed for the relationship between average tire tread depth and the test distance traveled by the test vehicle, on which the test tires are mounted. From this analysis a rate of wear is determined: groove depth loss per unit distance.  
1.4 Linear treadwear is defined as an essentially constant rate of wear, after break-in, which results in a linear regression coefficient of determination, R2, equal to or greater than 0.95 when obtained for a data set where the number of measurement intervals, n, is at least 3. Each measurement interval represents a specific test distance.  
1.5 This practice is not applicable to the prediction of treadlife for tires that exhibit non-linear or irregular treadwear.  
1.6 Evaluation parameters are given for both SI and inch-pound units; either may be used. The evaluation parameters as defined are ones typically used in the tire testing industry and no special claim is made for superiority of these parameters and terms over other terms and parameters that may be developed.  
1.7 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.

General Information

• Status: Published
• Publication Date: 30-Apr-2020
• ICS: 83.160.10 - Road vehicle tyres
• Technical Committee: F09 - Tires
• Drafting Committee: F09.30 - Laboratory (Non-Vehicular) Testing

Relations

• Replaces: ASTM F1016-07(2013)e1 - Standard Practice for Linear Tire Treadwear Data Analysis
• Effective Date: 01-May-2020
• Refers: ASTM F421-07(2013)e1 - Standard Test Method for Measuring Groove and Void Depth in Passenger Car Tires
• Effective Date: 01-Jun-2013
• Refers: ASTM F538-09 - Standard Terminology Relating to the Characteristics and Performance of Tires
• Effective Date: 15-Jun-2009
• Refers: ASTM F421-07 - Standard Test Method for Measuring Groove and Void Depth in Passenger Car Tires
• Effective Date: 01-Aug-2007
• Refers: ASTM F538-03 - Standard Terminology Relating to the Characteristics and Performance of Tires
• Effective Date: 01-Dec-2003
• Refers: ASTM F762-94(2000)e1 - Standard Test Method for Determining Change in Groove (or Void) Depth With Distance Traveled for Passenger Car Tires
• Effective Date: 10-May-2000
• Refers: ASTM F421-00 - Standard Test Method for Measuring Groove and Void Depth in Passenger Car Tires
• Effective Date: 10-May-2000
• Refers: ASTM F538-99 - Standard Terminology Relating to the Characteristics and Performance of Tires
• Effective Date: 10-Apr-1999
• Referred By: ASTM F762/F762M-08(2020)e1 - Standard Test Method for Determining Change in Groove (or Void) Depth With Distance Traveled for Passenger Car Tires
• Effective Date: 01-May-2020

Overview

ASTM F1016-07(2020), Standard Practice for Linear Tire Treadwear Data Analysis, establishes standardized methods for analyzing linear tire treadwear data through elementary linear regression. Developed by ASTM International, this practice harmonizes terminology, calculations, and reporting methods for evaluating tire treadwear, facilitating consistency across the tire testing industry. The standard specifically focuses on tires that demonstrate a linear, constant rate of wear, and ensures the use of internationally recognized principles, as outlined by the WTO Technical Barriers to Trade (TBT) Committee.

Key Topics

• Standardized Definitions: The standard provides precise definitions for key treadwear terms such as average tire tread depth, break-in period, fastest wearing groove/location, and projected treadlife.
• Linear Regression Analysis: Guidance is given on applying linear regression to analyze the relationship between average tire tread depth and test distance. The rate of wear is quantified as groove depth loss per unit of travel distance.
• Applicability: This practice is intended for use with tires exhibiting a consistent, linear treadwear pattern (coefficient of determination, R² ≥ 0.95 after break-in), and is not suitable for tires with irregular or non-linear wear.
• Measurement Intervals: At least three measurement intervals (test distances) are required, ensuring data robustness.
• Unit Flexibility: The standard supports both SI and inch-pound units for parameter evaluation, accommodating international and regional preferences.
• Performance Indexes: While the document standardizes calculation methods, it does not specify preference for particular treadwear performance indexes (e.g., distance per unit loss or loss per distance unit).

Applications

ASTM F1016-07(2020) is vital for organizations involved in tire research, manufacturing, quality control, and regulatory assessment. Key practical uses include:

• Quality Assurance: Tire manufacturers and independent laboratories use the standard to quantitatively compare treadwear performance between tire models, ensuring manufacturing consistency and verifying claims.
• Product Development: Engineering teams leverage the method to validate new tread compounds or designs by assessing linear wear characteristics under controlled conditions.
• Comparative Testing: Regulatory bodies or consumer organizations benefit from standardized methods for comparative treadwear analysis, enabling objective tire rating systems.
• Performance Index Calculation: The standard supports efficient calculation of key indicators such as rate of wear and projected treadlife, essential for product labeling, warranty terms, and consumer information.
• Global Trade Compliance: Adherence to ASTM F1016-07(2020) facilitates international market access by aligning with globally recognized test practices.

Related Standards

• ASTM F421: Describes the procedures for measuring groove and void depth in passenger car tires, providing primary data inputs for treadwear analysis.
• ASTM F762: Specifies methods for determining change in groove (or void) depth with distance traveled, underpinning the data collection process for treadwear studies.
• ASTM F538: Offers terminology relating to the characteristics and performance of tires, ensuring consistent use of key terms across testing activities.
• WTO TBT Principles: This standard was developed following principles established by the World Trade Organization for international standards development, supporting harmonization in global trade.

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Keywords: ASTM F1016, linear tire treadwear, tire tread analysis, treadwear data, groove depth, linear regression, treadwear performance, rate of wear, tire testing, projected treadlife

Standards Content (Sample)

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.
Designation: F1016 − 07 (Reapproved 2020)
Standard Practice for
Linear Tire Treadwear Data Analysis
This standard is issued under the fixed designation F1016; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 2. Referenced Documents
2.1 ASTM Standards:
1.1 This practice describes the elementary linear regression
F421 Test Method for Measuring Groove and Void Depth in
analysis of basic treadwear data as obtained according to Test
Passenger Car Tires
Method F421 and Test Method F762.
F538 Terminology Relating to the Characteristics and Per-
1.2 The basic treadwear data are obtained as groove depth
formance of Tires
loss measurements by procedures described in Test Method
F762 Test Method for Determining Change in Groove (or
F421 after a series of test cycles (test distances under specified
Void) Depth With Distance Traveled for Passenger Car
conditions) according to Test Method F762.
Tires
1.3 A linear regression analysis is performed for the rela-
3. Terminology
tionship between average tire tread depth and the test distance
3.1 Definitions:
traveledbythetestvehicle,onwhichthetesttiresaremounted.
3.1.1 average tire tread depth, [L],n—the average of all tire
From this analysis a rate of wear is determined: groove depth
groove (void) depth measurements. F538
loss per unit distance.
3.1.2 break-in, [L],n—one or more periods of initial stan-
1.4 Linear treadwear is defined as an essentially constant
dardized tire operation during which tire is brought to the state
rate of wear, after break-in, which results in a linear regression
which will lead to more consistent test results. F538
coefficient of determination, R , equal to or greater than 0.95
3.1.3 fastest wearing groove, [L],n—the circumferential
whenobtainedforadatasetwherethenumberofmeasurement
groove with the minimum life expectancy. F538
intervals, n, is at least 3. Each measurement interval represents
3.1.4 fastest wearing location, [L],n—that location which
a specific test distance.
exhibits the highest percent tread (depth) loss as calculated in
1.5 This practice is not applicable to the prediction of
6.1.1. F538
treadlife for tires that exhibit non-linear or irregular treadwear.
3.1.5 groove, average depth, [L],n—the average of all tire
1.6 Evaluation parameters are given for both SI and inch- groove depth measurements in a single groove. F538
pound units; either may be used. The evaluation parameters as
3.1.6 projected treadlife, [L],n—the test distance that gives
defined are ones typically used in the tire testing industry and
h as the average tread depth; where h is the height of treadwear
no special claim is made for superiority of these parameters
indicator above groove (or void) base. F538
and terms over other terms and parameters that may be
3.1.7 test distance, [L],n—distance traveled by a vehicle
developed.
after tire break-in. F538
1.7 This international standard was developed in accor-
4. Summary of Practice
dance with internationally recognized principles on standard-
ization established in the Decision on Principles for the
4.1 This practice provides a calculation procedure for linear
Development of International Standards, Guides and Recom-
regression analysis of treadwear data to be used in the tire
mendations issued by the World Trade Organization Technical
industry for assessing tire treadwear performance.
Barriers to Trade (TBT) Committee.
4.2 No specific mathematical formulas are given for the
customary least-squares calculations used for linear regression
parameter evaluation since these calculation algorithms are
This practice is under the jurisdiction ofASTM Committee F09 on Tires and is
the direct responsibility of Subcommittee F09.30 on Laboratory (Non-Vehicular)
Testing. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Current edition approved May 1, 2020. Published June 2020. Originally contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
ε1
approved in 1986. Last previous edition approved in 2013 as F1016 – 07 (2013) . Standards volume information, refer to the standard’s Document Summary page on
DOI: 10.1520/F1016-07R20. the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
F1016 − 07 (2020)
readily available with electronic hand calculators or statistical 1
IRW~1000 km/mm! 5 (5)
software for personal computers, or both.Terms are defined for RW~ mm/1000 km!
slope, intercept, and coefficient of determination.
IRW 1000 mi/mil 5 (6)
~ !
RW mils/1000 mi
~ !
5. Significance and Use
where RW = absolute loss in tread depth per unit test
5.1 The purpose of this practice is to standardize the
distance after break-in.
meaning and derivation of some terms and indexes that are
6.1.5 The wear performance index, a calculated value that
commonly used to characterize treadwear.
relates the wear performance of a candidate tire to that of a
5.1.1 There is no intent to recommend either of the two
control tire tested in the same test, may alternatively be
treadwear performance indexes: distance per unit loss of tread
calculatedonthebasisofeitherpercentlossortreaddepth((Eq
depth or loss of tread depth per distance unit.
7)) to giveTLI, a treadlife index, or on the basis of rate of wear
((Eq 8)) to give TWI, a treadwear index. The two are
6. Calculation
equivalent if the initial tread depth of the candidate tire is equal
6.1 Use the following calculations and terms to report
to that of the control tire.
treadwear:
% loss in control tire
6.1.1 The percentage tread (depth) loss (PTL) exp
...