ASTM F1016-07(2020)

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 service@astm.org. 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
...