ASTM D4632/D4632M-15a

Standard Test Method for Grab Breaking Load and Elongation of Geotextiles

SIGNIFICANCE AND USE
5.1 The grab method is applicable whenever it is desired to determine the “effective strength” of the fabric in use, that is, the strength of the material in a specific width, together with the additional strength contributed by adjacent material. There is no simple relationship between grab tests and strip tests since the amount of fabric assistance depends on the construction of the fabric. It is useful as a quality control or acceptance test.  
5.2 The procedure in Test Method D4632/D4632M for the determination of grab strength of geotextiles may be used for acceptance testing of commercial shipments, but caution is advised since information about between-laboratory precision is incomplete. Comparative tests as directed in 5.2.1 are advisable.  
5.2.1 In case of a dispute arising from differences in reported test results when using the procedures in Test Method D4632/D4632M for acceptance testing of commercial shipments, the purchaser and the manufacturer should conduct comparative tests to determine if there is a statistical bias between their laboratories. Competent statistical assistance is recommended for the investigation of bias. As a minimum, the two parties should take a group of test specimens that are as homogeneous as possible and which are from a lot of material of the type in question. The test specimens should then be randomly assigned in equal numbers to each laboratory for testing. The average results from the two laboratories should be compared using the appropriate Student's t-test and an acceptable probability level chosen by the two parties before testing is begun. If a bias is found, either its cause must be found and corrected or the purchaser and the manufacturer must agree to interpret future test results in the light of the known bias.  
5.3 Most geotextile fabrics can be tested by this test method. Some modification of clamping techniques may be necessary for a given fabric, depending upon its structure. Special adaptation may be nece...
SCOPE
1.1 This test method is an index test which provides a procedure for determining the breaking load (grab strength) and elongation (grab elongation) of geotextiles using the grab method. This test method is not suitable for knitted fabrics and alternate test methods should be used. While useful for quality control and acceptance testing for a specific fabric structure, the results can only be used comparatively between fabrics with very similar structures, because each different fabric structure performs in a unique and characteristic manner in this test. The grab test methods does not provide all the information needed for all design applications and other test methods should be used.  
1.2 Procedures for measuring the breaking load and elongation by the grab method in both the dry and wet state are included; however, testing is normally done in the dry condition unless specified otherwise in an agreement or specification.  
1.3 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 non-conformance with the standard.  
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: 14-May-2015
• ICS: 59.080.70 - Geotextiles
• Technical Committee: D35 - Geosynthetics
• Drafting Committee: D35.01 - Mechanical Properties

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: D4632/D4632M − 15a
Standard Test Method for
1
Grab Breaking Load and Elongation of Geotextiles
This standard is issued under the fixed designation D4632/D4632M; 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.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope D76/D76M Specification for Tensile Testing Machines for
Textiles
1.1 This test method is an index test which provides a
D123 Terminology Relating to Textiles
procedure for determining the breaking load (grab strength)
D1776/D1776M Practice for Conditioning and Testing Tex-
and elongation (grab elongation) of geotextiles using the grab
tiles
method. This test method is not suitable for knitted fabrics and
D2905 Practice for Statements on Number of Specimens for
alternate test methods should be used. While useful for quality
3
Textiles (Withdrawn 2008)
control and acceptance testing for a specific fabric structure,
D4354 Practice for Sampling of Geosynthetics and Rolled
the results can only be used comparatively between fabrics
Erosion Control Products(RECPs) for Testing
with very similar structures, because each different fabric
D4439 Terminology for Geosynthetics
structure performs in a unique and characteristic manner in this
E177 Practice for Use of the Terms Precision and Bias in
test. The grab test methods does not provide all the information
ASTM Test Methods
needed for all design applications and other test methods
E691 Practice for Conducting an Interlaboratory Study to
should be used.
Determine the Precision of a Test Method
1.2 Procedures for measuring the breaking load and elon-
gation by the grab method in both the dry and wet state are
3. Terminology
included; however, testing is normally done in the dry condi-
3.1 Definitions:
tion unless specified otherwise in an agreement or specifica-
3.1.1 atmosphere for testing geotextiles, n—air maintained
tion.
at a relative humidity of 65 6 5 % relative humidity and
1.3 The values stated in either SI units or inch-pound units
temperature of 21 6 2°C [70 6 4°F].
are to be regarded separately as standard. The values stated in
3.1.2 breaking load, n—the maximum force applied to a
each system may not be exact equivalents; therefore, each
specimen in a tensile test carried to rupture.
system shall be used independently of the other. Combining
3.1.3 cross-machine direction, n—the direction in the plane
values from the two systems may result in non-conformance
of the fabric perpendicular to the direction of manufacture.
with the standard.
3.1.4 elongation at break, n—the elongation corresponding
1.4 This standard does not purport to address all of the
to the breaking load, that is, the maximum load.
safety concerns, if any, associated with its use. It is the
3.1.5 geotextile, n—any permeable textile material used
responsibility of the user of this standard to establish appro-
with foundation, soil, rock, earth, or any other geotechnical
priate safety and health practices and determine the applica-
material, as an integral part of a man-made product, structure,
bility of regulatory limitations prior to use.
or system.
2. Referenced Documents
3.1.6 grab test, n—in fabric testing, a tension test in which
2
2.1 ASTM Standards: only a part of the width of the specimen is gripped in the
clamps.
3.1.6.1 Discussion—For example, if the specimen width is
1
This test method is under the jurisdiction of ASTM Committee D35 on
101.6 mm [4 in.] and the width of the jaw faces 25.4
Geosynthetics and is the direct responsibility of Subcommittee D35.01 on Mechani-
mm [1 in.], the specimen is gripped centrally in the clamps.
cal Properties.
Current edition approved May 15, 2015. Published June 2015. Originally
3.1.7 machine direction, n—the direction in the plane of the
approved in 1991. Last previous edition approved in 2015 as D4632/D4632M–15.
fabric parallel to the direction of manufacture.
DOI: 10.1520/D4632_D4632M-15A.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
3
Standards volume information, refer to the standard’s Document Summary page on The last approved version of this historical standard is referenced on
the ASTM website. www.astm.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
D4632/D4632M − 15a
3.1.8 For definitions of other terms used in this test method, 6. Apparatus
refer to Terminology D123 or Terminology D
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: D4632/D4632M − 15 D4632/D4632M − 15a
Standard Test Method for
1
Grab Breaking Load and Elongation of Geotextiles
This standard is issued under the fixed designation D4632/D4632M; 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.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope
1.1 This test method is an index test which provides a procedure for determining the breaking load (grab strength) and
elongation (grab elongation) of geotextiles using the grab method. This test method is not suitable for knitted fabrics and alternate
test methods should be used. While useful for quality control and acceptance testing for a specific fabric structure, the results can
only be used comparatively between fabrics with very similar structures, because each different fabric structure performs in a
unique and characteristic manner in this test. The grab test methods does not provide all the information needed for all design
applications and other test methods should be used.
1.2 Procedures for measuring the breaking load and elongation by the grab method in both the dry and wet state are included;
however, testing is normally done in the dry condition unless specified otherwise in an agreement or specification.
1.3 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 non-conformance with the standard.
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.
2. Referenced Documents
2
2.1 ASTM Standards:
D76/D76M Specification for Tensile Testing Machines for Textiles
D123 Terminology Relating to Textiles
D1776D1776/D1776M Practice for Conditioning and Testing Textiles
3
D2905 Practice for Statements on Number of Specimens for Textiles (Withdrawn 2008)
D4354 Practice for Sampling of Geosynthetics and Rolled Erosion Control Products(RECPs) for Testing
D4439 Terminology for Geosynthetics
E177 Practice for Use of the Terms Precision and Bias in ASTM Test Methods
E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
3. Terminology
3.1 Definitions:
3.1.1 atmosphere for testing geotextiles, n—air maintained at a relative humidity of 65 6 5 % relative humidity and temperature
of 21 6 2°C [70 6 4°F].
3.1.2 breaking load, n—the maximum force applied to a specimen in a tensile test carried to rupture.
3.1.3 cross-machine direction, n—the direction in the plane of the fabric perpendicular to the direction of manufacture.
3.1.4 elongation at break, n—the elongation corresponding to the breaking load, that is, the maximum load.
1
This test method is under the jurisdiction of ASTM Committee D35 on Geosynthetics and is the direct responsibility of Subcommittee D35.01 on Mechanical Properties.
Current edition approved Jan. 1, 2015May 15, 2015. Published February 2015June 2015. Originally approved in 1991. Last previous edition approved in 20132015 as
ε2
D4632/D4632M– 08(2013)–15. . DOI: 10.1520/D4632_D4632M-15.10.1520/D4632_D4632M-15A.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
3
The last approved version of this historical standard is referenced on www.astm.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
D4632/D4632M − 15a
3.1.5 geotextile, n—any permeable textile material used with foundation, soil, rock, earth, or any other geotechnical material,
as an integral part of a man-made product, structure, or system.
3.1.6 grab test, n—in fabric testing, a tension test in which only a part of the width of the specimen is gripped in the clamps.
3.1.6.1 Discussion—
For example, if the specimen
...