ASTM D4751-99a(2004)
(Test Method)Standard Test Method for Determining Apparent Opening Size of a Geotextile
Standard Test Method for Determining Apparent Opening Size of a Geotextile
SCOPE
1.1 This test method is used to determine the apparent opening size (AOS) of a geotextile by sieving glass beads through a geotextile.
1.2 This test method shows the values in both SI units and inch-pound units. "SI" units is the technically correct name for the system of metric units known as the International System of Units. "Inch-pound" units is the technically correct name for the customary units used in the United States. The values in inch-pound units are provided for information only.
1.3 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
Relations
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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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:D4751–99a (Reapproved 2004)
Standard Test Method for
Determining Apparent Opening Size of a Geotextile
This standard is issued under the fixed designation D 4751; 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 3.1.3 Discussion—The laboratory conditions are very im-
portant to the AOS test. For example, excessive humidity
1.1 This test method covers the determination the apparent
(above 70 %) can cause beads to stick together; while too low
opening size (AOS) of a geotextile by sieving glass beads
a relative humidity (below 50 %) can result in an increase in
through a geotextile.
static electricity.
1.2 This test method shows the values in both SI units and
3.1.4 geotechnics, n—the application of scientific methods
inch-pound units. SI units is the technically correct name for
and engineering principles to the acquisition, interpretation,
thesystemofmetricunitsknownastheInternationalSystemof
and use of knowledge of materials of the earth’s crust to the
Units. Inch-pound units is the technically correct name for the
solution of engineering problems.
customary units used in the United States. The values in
3.1.5 Discussion—Geotechnics embraces the fields of soil
inch-pound units are provided for information only.
mechanics, rock mechanics, and many of the engineering
1.3 This standard does not purport to address all of the
aspects of geology, geophysics, hydrology, and related sci-
safety concerns, if any, associated with its use. It is the
ences.
responsibility of the user of this standard to establish appro-
3.1.6 geotextile, n—any permeable textile material used
priate safety and health practices and determine the applica-
with foundation, soil, rock, earth, or any other geotechnical
bility of regulatory requirements prior to use.
engineering related material as an integral part of a man-made
2. Referenced Documents
project, structure, or system.
3.1.7 For the definitions of the other terms relating to
2.1 ASTM Standards:
geotextiles, refer to Terminology D 4439.
C 136 Test Method for Sieve Analysis of Fine and Coarse
3.2 For the definitions of the other terms relating to textiles,
Aggregates
refer to Terminology D 123.
D 123 Terminology Relating to Textiles
D 1776 Practice for Conditioning Textiles for Testing
4. Summary of Test Method
D 4238 Test Method for Electrostatic Propensity of Textiles
4.1 A geotextile specimen is placed in a sieve frame, and
D 4354 Practice for Sampling of Geosynthetics for Testing
sized glass beads are placed on the geotextile surface. The
D 4439 Terminology for Geotextiles
geotextile and frame are shaken laterally so that the jarring
E 11 Specification for Wire-Cloth Sieves for Testing Pur-
motion will induce the beads to pass through the test specimen.
poses
The procedure is repeated on the same specimen with various
3. Terminology
size glass beads until its apparent opening size has been
determined.
3.1 Definitions:
3.1.1 apparent opening size (AOS), O , n—for a geotex-
5. Significance and Use
tile, a property that indicates the approximate largest particle
5.1 Using a geotextile as a medium to retain soil particles
that would effectively pass through the geotextile.
necessitatescompatibilitybetweenitandtheadjacentsoil.This
3.1.2 atmosphere for testing geosynthetics, n—air main-
test method is used to indicate the apparent opening size in a
tained at a relative humidity between 50 to 70 % and a
geotextile, which reflects the approximate largest opening
temperature of 21 6 2°C (70 6 4°F).
dimension available for soil to pass through.
5.2 Test Method D 4751 for the determination of opening
This test method is under the jurisdiction of ASTM Committee D35 on
size of geotextiles is acceptable for testing of commercial
Geosynthetics and is the direct responsibility of Subcommittee D35.03 on Perme-
shipments of geotextiles. Current estimates of precision, be-
ability and Filtration.
tween laboratories, are being established.
Current edition approved July 1, 2004. Published July 2004. Originally approved
in 1993. Last previous version approved in 1999 as D 4751 – 99a.
5.2.1 In case of a dispute arising from differences in
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
reported test results when using Test Method D 4751 for
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
acceptance testing of commercial shipments, the purchaser and
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. the supplier should conduct comparative tests to determine if
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D4751–99a (2004)
TABLE 1 Glass Bead Sizes
prior to beginning the test. Bead sizes to be used in this test
Bead Size Range method are shown in Table 1.
A
6.4 Balance, having a capacity adequate for the mass of
Passing Retained Bead Size Designation
samples anticipated and accurate to 60.05 g.
Sieve Sieve Sieve
mm mm mm
B B
Number Number Number 6.5 Static Elimination, to prevent the accumulation of static
electricity when the beads are shaken on the surface of
2.0 101.70 121.7 12
1.4 14 1.18 16 1.18 16
geotextile. Commercially available devices or anti-static
1.00 18 0.850 20 0.850 20
sprays are acceptable.
0.710 25 0.600 30 0.600 30
6.6 Pan, for collecting sieved beads.
0.500 35 0.425 40 0.425 40
0.355 45 0.300 50 0.300 50
0.250 60 0.212 70 0.212 70 7. Sampling
0.180 80 0.150 100 0.150 100
7.1 Lot Sample—For routine quality control testing, divide
0.125 120 0.106 140 0.106 140
0.090 170 0.075 200 0.075 200
the product into lots and take the lot sample as directed in
A
The designated bead size is the “retained on” size of the sieve pair used to size Practice D 4354, Section 7 Procedure B Sampling for Quality
the beads. For example, beads designated No. 40 are beads that pass the No. 35
Assurance Testing. For Specification Conformance testing,
sieve and are retained on the No. 40 sieve. These beads are typically sold as
sample as directed in Practice D 4354, Section 6 Procedure
35-40 beads.
B
See Specification E 11. A—Sampling for Specification Conformance.
7.2 Laboratory Sample—As a laboratory sample for accep-
tancetesting,takeafullwidthswatch1-m(1-yd)longfromthe
there is a statistical bias between their laboratories. Competent
endofeachrolloffabricinthelotsample,afterfirstdiscarding
statistical assistance is recommended for the investigation of
a minimum of1m(1yd)of fabric from the very outside of the
bias.As a minimum, the two parties should take a group of test
roll.
specimens that are homogeneous as possible and that are from
7.3 Test Specimens—Cut five specimens from each swatch
a lot of material of the type in question. The test specimens
inthelaboratorysamplewitheachspecimenbeingcuttofitthe
should then be randomly assigned in equal numbers to each
appropriate sieve pan. Cut the specimens from a single swatch
laboratory for testing. The average results from the two
spaced along a diagonal line on the swatch.
laboratories should be compared using Students t-test for
unpaireddataandanacceptableprobabilitylevelchosenbythe
8. Specimen Preparation
two parties before the testing is begun. If a bias is found, either
8.1 Weigh the specimens and then submerge them in dis-
its cause must be found and corrected or the purchaser and the
tilledwaterfor1hatthestandardatmospherefortesting.Bring
supplier must agree to interpret future test results in the light of
the specimens to moisture equilibrium in the atmosphere for
the known bias.
testing geosynthetics. Equilibrium is considered to have been
reached when the change in the mass of the specimen in
6. Apparatus
successive weighings made at intervals of not less than 2 h
6.1 Mechanical Sieve Shaker—A mechanical sieve shaker,
does not exceed 0.1 g.
which imparts lateral and vertical motion to the sieve, causing
NOTE 2—It is recognized that in practice, geosynthetic materials are
the particles thereon to bounce and turn so as to present
frequently not weighed to determine when moisture equilibrium has been
different orientations to the sieving surface, should be used.
reached. While such a method cannot be accepted in cases of dispute, it
The sieve shaker should be a constant frequency device
may be sufficient in routine testing to expose the material to the standard
utilizing a tapping arm to impart the proper motion to the glass
atmosphere for testing geosynthetics for a reasonable period of time
beads.
before the specimens are tested. A time of at least 24 h has been found
acceptable in most cases. However, certain fibers may contain more
NOTE 1—Care should be given to the cork or rubber contact point on
moisture upon receipt than after conditioning. When this is known, a
shakers when the vertical motion comes from an arm striking the cork or
preconditioning cycle, as described in Practice D 1776, may be agreed
rubber. Excessive wear on the cork or rubber could affect the motion
upon by the co
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.