ASTM D5262-97

Standard Test Method for Evaluating the Unconfined Tension Creep Behavior of Geosynthetics

SCOPE
1.1 This test method is intended for use in determining the unconfined tension creep behavior of geosynthetics at constant temperature when subjected to a sustained tensile loading. This test method is applicable to all geosynthetics.
1.2 The test method measures total elongation of the geosynthetic test specimen, from the time of loading, while being maintained at a constant temperature. It includes procedures for measuring the tension creep behavior at constant temperature of conditioned geosynthetics as well as directions for calculating tension creep curves.
1.3 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.
1.4 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 and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 09-Dec-1997
• ICS: 59.080.70 - Geotextiles
• Technical Committee: D35 - Geosynthetics
• Drafting Committee: D35.02 - Endurance Properties

Relations

• Replaced By: ASTM D5262-02a - Standard Test Method for Evaluating the Unconfined Tension Creep Behavior of Geosynthetics
• Effective Date: 10-Dec-2002
• Referred By: ASTM D8269-21 - Standard Guide for the Use of Geocells in Geotechnical and Roadway Projects
• Effective Date: 10-Dec-1997
• Referred By: ASTM D6637/D6637M-15 - Standard Test Method for Determining Tensile Properties of Geogrids by the Single or Multi-Rib Tensile Method
• Effective Date: 10-Dec-1997
• Referred By: ASTM D8105-18 - Standard Guide for Use and Application of Geosynthetic Reinforcement Reduction Factor Test Results
• Effective Date: 10-Dec-1997
• Referred By: ASTM D7361-07(2023) - Standard Test Method for Accelerated Compressive Creep of Geosynthetic Materials Based on Time-Temperature Superposition Using the Stepped Isothermal Method
• Effective Date: 10-Dec-1997
• Referred By: ASTM D7737/D7737M-15(2023) - Standard Test Method for Individual Geogrid Junction Strength
• Effective Date: 10-Dec-1997
• Referred By: ASTM D6992-16(2023) - Standard Test Method for Accelerated Tensile Creep and Creep-Rupture of Geosynthetic Materials Based on Time-Temperature Superposition Using the Stepped Isothermal Method
• Effective Date: 10-Dec-1997
• Referred By: ASTM E2777-20 - Standard Guide for Vegetative (Green) Roof Systems
• Effective Date: 10-Dec-1997
• Referred By: ASTM D5819-22 - Standard Guide for Selecting Test Methods for Experimental Evaluation of Geosynthetic Durability
• Effective Date: 10-Dec-1997
• Referred By: ASTM D4439-23b - Standard Terminology for Geosynthetics
• Effective Date: 10-Dec-1997
• Referred By: ASTM D6455-11(2018) - Standard Guide for the Selection of Test Methods for Prefabricated Bituminous Geomembranes (PBGMs)
• Effective Date: 10-Dec-1997

Standards Content (Sample)

NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
Designation: D 5262 – 97
Standard Test Method for
Evaluating the Unconfined Tension Creep Behavior of
Geosynthetics
This standard is issued under the fixed designation D 5262; 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 (e) indicates an editorial change since the last revision or reapproval.
1. Scope E 6 Terminology Relating to Methods of Mechanical Test-
ing
1.1 This test method is intended for use in determining the
unconfined tension creep behavior of geosynthetics at constant
3. Terminology
temperature when subjected to a sustained tensile loading. This
3.1 Definitions—For definitions of many terms used in this
test method is applicable to all geosynthetics.
test method, refer to Terminologies D 123, D 4439 and E 6.
1.2 The test method measures total elongation of the geo-
3.2 Descriptions of Terms Specific to This Standard:
synthetic test specimen, from the time of loading, while being
3.2.1 atmosphere for testing geosynthetics, n—air main-
maintained at a constant temperature. It includes procedures
tained at a relative humidity between 50 and 70 % and
for measuring the tension creep behavior at constant tempera-
temperature of 21 6 2°C (70 6 4°F).
ture of conditioned geosynthetics as well as directions for
3.2.2 creep, n—the time-dependent increase in accumula-
calculating tension creep curves.
tive strain in a material resulting from an applied constant
1.3 The values stated in SI units are to be regarded as the
force.
standard. The values given in parentheses are for information
3.2.3 design load—the load at which the geosynthetic is
only.
required to operate in order to perform its intended function.
1.4 This standard does not purport to address all of the
3.2.4 failure, n—an arbitrary point at which a material
safety concerns, if any, associated with its use. It is the
ceases to be functionally capable of its intended use.
responsibility of the user of this standard to establish appro-
3.2.5 geogrid, n—a geosynthetic formed by a regular net-
priate safety and health practices and determine the applica-
work of integrally connected elements with apertures greater
bility of regulatory limitations prior to use.
than 6.35 mm ( ⁄4 in.) to allow interlocking with surrounding
2. Referenced Documents soil, rock, earth, and other surrounding materials to function
primarily as reinforcement.
2.1 ASTM Standards:
3.2.6 geomembrane, n—an essentially impermeable geo-
D 123 Terminology Relating to Textiles
synthetic composed of one or more synthetic sheets.
D 1776 Practice for Conditioning Textiles for Testing
3.2.6.1 Discussion—In geotechnical engineering, essen-
D 1909 Table for Commercial Moisture Regains for Textile
tially impermeable means that no measurable liquid flows
Fibers
through a geosynthetic when tested in accordance with Test
D 2990 Test Methods for Tensile, Compressive, and Flex-
Methods D 4491.
ural Creep and Creep Rupture of Plastics
3.2.7 geosynthetic, n—a planar product manufactured from
D 4354 Practice for Sampling of Geosynthetics for Testing
4 polymeric material used with soil, rock, earth, or other geo-
D 4439 Terminology for Geosynthetics
technical engineering-related material as an integral part of a
D 4491 Test Methods for Water Permeability of Geotextiles
4 man-made project, structure, or system.
by Permittivity
3.2.8 geotextile, n—a permeable geosynthetic comprised
D 4595 Test Method for Tensile Properties of Geotextiles
4 solely of textiles.
by the Wide-Width Strip Method
3.2.8.1 Discussion—Current manufacturing techniques pro-
D 4885 Test Method for Determining Performance Tensile
4 duce nonwoven fabrics, knitted (non-tubular) fabrics, and
Strength of Geomembranes Using Wide Strip Testing
woven fabrics.
3.2.9 index test, n—a test procedure that may contain a
known bias, but that may be used to establish an order for a set
This test method is under the jurisdiction of ASTM Committee D-35 on
Geosynthetics and is the direct responsibility of Subcommittee D35.02 on Endur-
of specimens with respect to the property being measured.
ance Properties.
3.2.10 rate of creep, n—the slope of the creep-time curve at
Current edition approved Dec. 10, 1997. Published August 1998. Originally
a given time.
published as D 5262 – 92. Last previous edition D 5262 – 95.
Annual Book of ASTM Standards, Vol 07.01.
Annual Book of ASTM Standards, Vol 08.02.
4 5
Annual Book of ASTM Standards, Vol 04.09. Annual Book of ASTM Standards, Vol 03.01.
Copyright © ASTM, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959, United States.
NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
D 5262
−1
3.2.11 tensile creep rupture strength, [FL ], n—for geo- centering of the specimen prior to application of the load.
synthetics, the force per unit width that will produce failure by 6.1.2 Geotextiles and Geomembranes—Each clamp shall be
sufficiently wide to grip the entire width of the specimen, 200
rupture in a creep test in a given time, at a specified constant
environment. mm (8.0 in.), and a minimum of 50-mm (2.0-in.) length in the
direction of the applied force.
3.2.12 tensile creep strain, n—the total strain at any given
6.1.3 Geogrids—These should be clamped to assure com-
time.
plete tension load transfer through test direction members. The
3.2.13 wide strip tensile test, n—for geosynthetics, a tensile
type of clamp and load transfer mechanism should be detailed
test in which the entire width of a 200-mm (8.0 in.)-wide
in the test report. Roller grips or low melting point alloy with
specimen is gripped in the clamps with a gage length of 100
adequate strength may be used to assist proper clamping.
mm (4.0 in.).
6.1.4 Other Related Products—Where special clamps are
used to grip these products, they should conform to the general
4. Summary of Test Method
requirements for clamps used to grip geotextiles, geomem-
4.1 The tension creep behavior of geosynthetics is measured
branes, and geogrids, and the clamping methods used should
by applying a sustained load in one step and measuring the
always be detailed in the report.
total elongation of the test specimen as a function of time while
6.2 Loading System—The loading system must be designed
maintaining a specified temperature and humidity. Unless
so that the load applied and maintained on the specimen is
otherwise stipulated, a temperature of 21 6 2°C (70 6 4°F)
within 61 % of the desired load. Loads may be applied by
and relative humidity of between 50 and 70 % shall be used. weights, weights and fulcrums, or pneumatics. The loading
mechanism must permit reproducibly rapid and smooth load-
5. Significance and Use ing, as specified in 11.4. No dynamic forces on placement of
the loads shall be allowed. Provision must also be made to
5.1 This test method is developed for use in the determina-
ensure that shock loading, caused by specimen failure, is not
tion of anticipated total elongation that may occur in geosyn-
transferred to other specimens undergoing testing.
thetics under sustained loading conditions.
6.3 Extension Measurement—Extensometers are preferred
5.1.1 The test data can be used in conjunction with inter-
for the measurement of elongation in geosynthetics. Whenever
pretive methods to evaluate creep strain potential at design
possible, other means of measuring elongation should be
loads.
calibrated against extensometers. In any case, the device
5.2 This test method is not intended for routine acceptance
chosen shall be capable of measuring deformations to an
testing of geosynthetics. This test method should be used to
accuracy of at least 0.003 6 mm (0.0001 6 in.). The means of
characterize geosynthetics intended for use in applications in
measuring elongation should be indicated clearly in the report.
which creep is of concern. The plane strain condition imposed
6.4 Vibration Control—Creep tests are sensitive to shock
during testing must be considered when using the test results
and vibration. The location of the apparatus, test equipment,
for design.
and mounting shall be designed so that the specimen is isolated
5.3 The basic distinctions between this test method and from vibration. Multi-station test equipment must be of suffi-
other test methods for measuring tension creep behavior are (1) cient rigidity so that no significant deflection due to shock or
the width of the specimens tested and (2) the measurement of vibration occurs during creep testing.
total elongation from the time of specimen loading. The greater 6.5 Time Measurement—The accuracy of the time measur-
widths of the specimens specified in this test method minimize ing device shall be 61 % of the elapsed time of each creep
the contraction edge effect (necking) that occurs in many measurement load increment.
6.6 Temperature Control and Measurement:
geosynthetic materials and provides a closer relationship to
actual material behavior in plane strain tension conditions. 6.6.1 The temperature in the test space, especially close to
the gage length of the specimen, shall be maintained within
5.4 The creep of a given geosynthetic is likely to be reduced
62°C (64°F) of the targeted value by a suitable automatic
in soil because of load transfer to the soil. The unconfined
device and shall be stated in the report. It is generally
environment represents a controlled test, in which the results
recognized that thermal contraction and expansion, associated
are conservative with regard to the behavior of the material in
with small temperature changes during the test, may produce
service. Confined or in-soil testing may model the field
changes in the apparent creep rate, especially near the transi-
behavior of the geosynthetic more accurately.
tion temperature.
6.6.2 Temperature measurements shall be recorded at fre-
6. Apparatus
quent intervals, or recorded continuously, in order to ensure an
6.1 Clamps:
accurate determination of the average test temperature and
6.1.1 Clamps should be at least as wide as the specimen,
compliance with 6.6.1.
with appropriate clamping power that will prevent slipping or
6.7 Environmental Control and Measurement:
damage of the test specimen within or at the faces of the
6.7.1 When the test environment is air, the relative humidity
clamps. The clamps and clamping technique shall be designed
shall be maintained between 50 and 70 % unless the creep
to minimize eccentric loading of the specimen. A swivel or
universal joint shall be used on one of the clamps at the end of
Examples of clamping, loading, and extensometer systems that have been used
the specimen. It is recommended that clamps permit the final successfully are found in the appendixes.
NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
D 5262
behavior of the geosynthetic has been shown to be unaffected 8.1.4 This test method may not be suitable for some woven
by humidity. The relative humidity shall be recorded at geotextiles or geogrids that exhibit breaking strengths in excess
frequent intervals to ensure that an accurate determination of of 100 kN/m (600 lbf/in.), due to clamping and equipment
the average test humidity can be made. limitations.
6.7.2 The test environment shall be maintained constant 8.1.4.1 In such cases, 100-mm (4.0-in.) width specimens
throughout the test. Safety precautions should be taken to avoid may be substituted for 200-mm (8.0-in.) width specimens, with
personal contact during the test. The area should be isolated the limitation that geogrids be tested with a minimum of three
adequately and fenced such that only the test operator has longitudinal members to assure proper load distribution. For
access to the test station. those geosynthetics, contraction edge effect (necking) is mini-
mal and the standard comparison can consequently continue to
7. Sampling
be made.
7.1 Laboratory Sample—For the laboratory sample, take a
full-width swatch approximately 1-m (40-in.) long in the
9. Number of Tests
machine direction from each roll in the lot sample. The sample
9.1 Unless otherwise agreed upon, creep tests shall be
may be taken from the end portion of a roll, provided there is
conducted at load levels as specified by the designer. Four load
no evidence that it is different from other portions of the roll.
levels are recommended for characterization of the material.
7.2 Test Specimens:
Loads shall be selected at intervals of approximately 10 % of
7.2.1 Geotextiles and Geomembranes—For tests in the
the maximum load per unit width, that is, 20, 30, 40, and 60 %,
machine and cross-machine directions, respectively, take from
as determined by applicable ASTM test methods.
each sample the number of specimens as directed in 9.1. Take
NOTE 2—It is generally recognized that characterization involves iden-
the specimens from a diagonal on the sample, with no
tification of the load levels at which there is no creep (no increase in strain
specimens closer than ⁄10 the width of the roll or 150 mm (6
with the log of time), low to moderate creep (linear increase in strain with
in.), whichever is smaller. For geomembranes, exercise care in
the log of time), and high creep (exponential increase in strain with the log
selecting, cutting, and preparing the specimens to avoid nicks,
of time).
tears, scratches, folds, or other imperfections that are likely to
9.2 To evaluate design creep strains, it is recommended that
cause premature failure.
a minimum of two creep tests be performed (that is, one at the
NOTE 1—Nonreinforced geomembranes are extremely sensitive in this
design load and one at a load that exceeds the design load, as
regard.
specified by the designer).
7.2.2 Geogrids and other Related Products—For tests in the
10. Conditioning and Testing Atmosphere
machine and cross-machine directions, respectively, take from
each sample the number of specimens as directed in 9.1. Take
10.1 Bring the specimens to moisture equilibrium in the
the specimens at random from the laboratory sample, with atmosphere for testing geosynthetics. Equilibrium is consid-
those for the measurement of machine direction creep proper-
ered to have been reached when the increase in mass of the
ties from different positions across the width, and those for the specimen, in successive weighings made at intervals of not less
measurement of cross-machine creep properties from different
than 2 h, does not exceed 0.1 % of the specimen mass.
...