ASTM D5994/D5994M-10(2015)e1

Standard Test Method for Measuring Core Thickness of Textured Geomembranes

SIGNIFICANCE AND USE
5.1 Thickness is one of the basic index properties used to control and track the quality of many geomembranes. Additionally, many mechanical properties (for example, tensile yield strength, puncture strength, etc.) can be related to core thickness. Core thickness values may also be required in calculation of some parameters such as diffusion coefficients or tensile stresses.  
5.2 The measured core thickness of geomembranes may vary considerably depending on the pressure applied to the specimen during measurement. To reduce variation in measurements and the chance of unrealistically low values due to excessively high pressures, a specific gauge point geometry and applied force are prescribed in this test method.  
5.3 The test method is applicable to all commonly available textured geomembranes that are deployed as manufactured geomembrane sheets.
SCOPE
1.1 This test method covers a procedure to measure the core thickness of textured geomembranes.  
1.2 This test method does not provide thickness values for geomembranes under variable normal stresses.  
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: 30-Apr-2015
• ICS: 59.080.70 - Geotextiles
• Technical Committee: D35 - Geosynthetics
• Drafting Committee: D35.10 - Geomembranes

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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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
´1
Designation: D5994/D5994M − 10 (Reapproved 2015)
Standard Test Method for
Measuring Core Thickness of Textured Geomembranes
This standard is issued under the fixed designation D5994/D5994M; 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.
ε NOTE—Designation was changed to dual and units information was corrected editorially in June 2015.
1. Scope 3. Terminology
3.1 For definitions of other terms relating to geomembranes
1.1 This test method covers a procedure to measure the core
used in this test method, refer to the Terminology D4439.
thickness of textured geomembranes.
3.2 Definitions:
1.2 This test method does not provide thickness values for
3.2.1 core thickness, n—the average thickness of a textured
geomembranes under variable normal stresses.
geomembrane as measured using this particular test method.
1.3 The values stated in either SI units or inch-pound units
3.2.2 geomembrane, n—anessentiallyimpermeablegeosyn-
are to be regarded separately as standard. The values stated in
thetic composed of one or more synthetic sheets. D4439
each system may not be exact equivalents; therefore, each
3.2.3 pressure, n—the force or load per unit area.
system shall be used independently of the other. Combining
3.2.4 textured geomembrane, n—a geomembrane having
values from the two systems may result in non-conformance
one or both surfaces intentionally manufactured with projec-
with the standard.
tions or indentations, most commonly for the purpose of
1.4 This standard does not purport to address all of the
providing increased shear strength against adjacent materials.
safety concerns, if any, associated with its use. It is the
3.2.5 thickness, n—the perpendicular distance between one
responsibility of the user of this standard to establish appro-
surface and its opposite.
priate safety and health practices and determine the applica-
bility of regulatory limitations prior to use. 3.2.6 thickness gauge points, n—the tips of a thickness
gauge which contact the upper and lower geomembrane
surfaces, and between which the thickness is measured.
2. Referenced Documents
2.1 ASTM Standards:
4. Summary of Test Method
D4354 Practice for Sampling of Geosynthetics and Rolled
4.1 The core thickness of a textured geomembrane is
Erosion Control Products (RECPs) for Testing
calculated as the average value of measurements taken on
D4439 Terminology for Geosynthetics
replicate specimens of the sample under investigation. The
E177 Practice for Use of the Terms Precision and Bias in
thicknessofeachspecimenismeasuredataspecificlocationas
ASTM Test Methods
thedistancebetweentwogaugepoints.Theopposingthickness
E691 Practice for Conducting an Interlaboratory Study to
gauge points are manufactured to a defined geometry, with a
Determine the Precision of a Test Method
specified force of 0.56 6 0.05 N [2.0 6 0.2 oz] applied along
E2554 Practice for Estimating and Monitoring the Uncer-
their axis.
tainty of Test Results of a Test Method Using Control
Chart Techniques
5. Significance and Use
5.1 Thickness is one of the basic index properties used to
control and track the quality of many geomembranes.
This test method is under the jurisdiction of ASTM Committee D35 on
Additionally, many mechanical properties (for example, tensile
GeosyntheticsandisthedirectresponsibilityofSubcommitteeD35.10onGeomem-
branes.
yield strength, puncture strength, etc.) can be related to core
Current edition approved May 1, 2015. Published June 2015. Originally
thickness. Core thickness values may also be required in
approved in 1996. Last previous edition approved in 2010 as D5994–10. DOI:
calculation of some parameters such as diffusion coefficients or
10.1520/D5994_D5994M-10R15E01.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or tensile stresses.
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
5.2 The measured core thickness of geomembranes may
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. vary considerably depending on the pressure applied to the
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
´1
D5994/D5994M − 10 (2015)
specimenduringmeasurement.Toreducevariationinmeasure- canbemet.Excludetheinnerandouterwrapsoftherollorany
ments and the chance of unrealistically low values due to material not representative of the sample (see Note 1).
excessively high pressures, a specific gauge point geometry
7.2 Remove test specimens from the sample in a randomly
and applied force are prescribed in this test method.
distributed pattern across the width. The thickness readings
5.3 The test method is applicable to all commonly available
must include measurements within 15 cm [6 in.] of both edges
textured geomembranes that are deployed as manufactured of the geomembrane roll.
geomembrane sheets.
7.3 Test Specimens—From each unit in the sample, remove
the specimens so that the edge of the specimen will extend
6. Apparatus
beyond the edge of the gauge points by 10 mm [0.4 in.] in all
6.1 Thickness Gauge—The thickness gauge shall be of the
directions. It is recommended to use circular test specimens of
dead-weight type capable of measuring to an accuracy of at
approximately 75 mm [3 in.] diameter.
least 60.01 mm [0.0004 in.].The gauge shall be constructed to
7.4 Number of Specimens—Unless otherwise agreed upon,
permit application of a specific force of 0.56 6 0.05 N [2.0 6
as when provided in an applicable material specification, take
0.2 oz]. The gauge shall have a base point (or anvil) and a
a number of test specimens per sample such that the user may
free-movingpresserpointwhoseaxesarealignedtoeachother.
expect, at the 95 % probability level, that the test result is not
NOTE 1—The geomembrane specimen being measured should be
more than 5 % of the average above or below the true average
maintained perpendicular to the axes of the opposing gauge points. An
of the sample. Determine the number of specimens per sample
underlying support system may be necessary to support large test
as follows:
specimens.
7.4.1 Reliable Estimate of v—When there is a reliable
6.2 Thickness Gauge Points—The gauge points shall be
estimate of v based upon extensive sample records for similar
made of hardened steel. The points shall be tapered at an angle
materials tested in the user’s laboratory as directed in the
of 60 6 2° to the horizontal with the tip rounded to a radius of
method, calculate the required number of specimens as fol-
0.8 6 0.1 mm [0.031 6 0.004 in.]. Fig. 1 shows the critical
lows:
dimensions.
n 5 tv/A (1)
~ !
NOTE 2—The gauge and points can be calibrated using standard
thickness blocks. Frequent use and rough use of the gauge can dull the
where:
gauge points and cause misalignment, both of which will cause incorrect
n = number of test specimens (rounded upward to a whole
readings. These problems can be detected by frequent calibration.
number),
t = the value of Student’s “t” for one-sided limits (seeTable
7. Sampling
1 in Practice D4354), a 95 % probability level, and the
7.1 Sample—For the sample, take a full width sample of
degrees of freedom associated with the estimate of v,
sufficient length so that the requirements of 7.2 through 7.4.2
FIG. 1 Dead Weight Thickness Measurement Device for Textured Geomembranes
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D5994/D5994M − 10 (2015)
11.1.7 Report the individual specimen thickness measure-
v = reliable estimate of the coefficient of variation of indi-
ments to the nearest 0.025 mm or 0.001 in.
vidual observations on similar materials in the user’s
11.1.8 Rep
...

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.
´1
Designation: D5994 − 10 D5994/D5994M − 10 (Reapproved 2015)
Standard Test Method for
Measuring Core Thickness of Textured Geomembranes
This standard is issued under the fixed designation D5994;D5994/D5994M; 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.
ε NOTE—Designation was changed to dual and units information was corrected editorially in June 2015.
1. Scope
1.1 This test method covers a procedure to measure the core thickness of textured geomembranes.
1.2 This test method does not provide thickness values for geomembranes under variable normal stresses.
1.3 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The inch-pound values
given in parentheses are for information only.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
2.1 ASTM Standards:
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
E2554 Practice for Estimating and Monitoring the Uncertainty of Test Results of a Test Method Using Control Chart Techniques
3. Terminology
3.1 For definitions of other terms relating to geomembranes used in this test method, refer to the Terminology D4439.
3.2 Definitions:
3.2.1 core thickness, n—the average thickness of a textured geomembrane as measured using this particular test method.
3.2.2 geomembrane, n—an essentially impermeable geosynthetic composed of one or more synthetic sheets. D4439
3.2.3 pressure, n—the force or load per unit area.
3.2.4 textured geomembrane, n—a geomembrane having one or both surfaces intentionally manufactured with projections or
indentations, most commonly for the purpose of providing increased shear strength against adjacent materials.
3.2.5 thickness, n—the perpendicular distance between one surface and its opposite.
3.2.6 thickness gauge points, n—the tips of a thickness gauge which contact the upper and lower geomembrane surfaces, and
between which the thickness is measured.
4. Summary of Test Method
4.1 The core thickness of a textured geomembrane is calculated as the average value of measurements taken on replicate
specimens of the sample under investigation. The thickness of each specimen is measured at a specific location as the distance
between two gauge points. The opposing thickness gauge points are manufactured to a defined geometry, with a specified force
of 0.56 6 0.05 N (2.0[2.0 6 0.2 oz)oz] applied along their axis.
This test method is under the jurisdiction of ASTM Committee D35 on Geosynthetics and is the direct responsibility of Subcommittee D35.10 on Geomembranes.
Current edition approved July 1, 2010May 1, 2015. Published September 2010June 2015. Originally approved in 1996. Last previous edition approved in 20032010 as
D5994–98(2003).D5994–10. DOI: 10.1520/D5994-10.10.1520/D5994_D5994M-10R15E01.
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.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
´1
D5994/D5994M − 10 (2015)
5. Significance and Use
5.1 Thickness is one of the basic index properties used to control and track the quality of many geomembranes. Additionally,
many mechanical properties (for example, tensile yield strength, puncture strength, etc.) can be related to core thickness. Core
thickness values may also be required in calculation of some parameters such as diffusion coefficients or tensile stresses.
5.2 The measured core thickness of geomembranes may vary considerably depending on the pressure applied to the specimen
during measurement. To reduce variation in measurements and the chance of unrealistically low values due to excessively high
pressures, a specific gauge point geometry and applied force are prescribed in this test method.
5.3 The test method is applicable to all commonly available textured geomembranes that are deployed as manufactured
geomembrane sheets.
6. Apparatus
6.1 Thickness Gauge—The thickness gauge shall be of the dead-weight type capable of measuring to an accuracy of at least
60.01 mm (0.0004 in.).[0.0004 in.]. The gauge shall be constructed to permit application of a specific force of 0.56 6 0.05 N
(2.0[2.0 6 0.2 oz).oz]. The gauge shall have a base point (or anvil) and a free-moving presser point whose axes are aligned to each
other.
NOTE 1—The geomembrane specimen being measured should be maintained perpendicular to the axes of the opposing gauge points. An underlying
support system may be necessary to support large test specimens.
6.2 Thickness Gauge Points—The gauge points shall be made of hardened steel. The points shall be tapered at an angle of 60
6 2° to the horizontal with the tip rounded to a radius of 0.8 6 0.1 mm (0.031[0.031 6 0.004 in.).in.]. Fig. 1 shows the critical
dimensions.
NOTE 2—The gauge and points can be calibrated using standard thickness blocks. Frequent use and rough use of the gauge can dull the gauge points
and cause misalignment, both of which will cause incorrect readings. These problems can be detected by frequent calibration.
7. Sampling
7.1 Sample—For the sample, take a full width sample of sufficient length so that the requirements of 7.2 through 7.4.2 can be
met. Exclude the inner and outer wraps of the roll or any material not representative of the sample (see Note 1).
7.2 Remove test specimens from the sample in a randomly distributed pattern across the width. The thickness readings must
include measurements within 15 cm (6 in.)[6 in.] of both edges of the geomembrane roll.
7.3 Test Specimens—From each unit in the sample, remove the specimens so that the edge of the specimen will extend beyond
the edge of the gauge points by 10 mm (0.4 in.)[0.4 in.] in all directions. It is recommended to use circular test specimens of
approximately 75 mm (3 in.)[3 in.] diameter.
FIG. 1 Dead Weight Thickness Measurement Device for Textured Geomembranes
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D5994/D5994M − 10 (2015)
7.4 Number of Specimens—Unless otherwise agreed upon, as when provided in an applicable material specification, take a
number of test specimens per sample such that the user may expect, at the 95 % probability level, that the test result is not more
than 5 % of the average above or below the true average of the sample. Determine the number of specimens per sample as follows:
7.4.1 Reliable Estimate of v—When there is a reliable estimate of v based upon extensive sample records for similar materials
tested in the user’s laboratory as directed in the method, calculate the required number of specimens as followsfollows::
TABLE 1 Core Thickness of Textured Geomembrane using D5994D5994/D5994M (mils)
A
Sample Average Repeatability Reproducibility Repeatability Reproducibility
Standard Deviation Standard Deviation Limit Limit
s s r R
x¯ r R
1 59.03 0.60 1.30 1.67 3.65
2 38.80 0.52 1.00 1.46 2.79
3 57.54 0.46 0.81 1.28 2.27
4 38.39 0.60 1.27 1.67 3.56
5 64.78 0.52 1.49 1.46 4.16
A
...