Significance and Use
GCLs must be properly manufactured in a manner consistent with a minimum level of quality control as determined by in-house testing of the final product. This practice suggests the types of tests, the methods of the testing and the minimum testing frequencies.
It should be clearly recognized that manufacturers may perform additional tests or at greater frequency than required in this practice, or both. In this case, the manufacturer's quality control plan will then take precedence over this practice. The quoted tests and test methods in Table 1 must appear in the QC plan and the QC report.
It should also be recognized that purchasers and installers of GCLs may require additional tests or at a great frequency than called for in this practice, or both. The organization(s) producing such project specific specification or quality assurance plan should recognize that such requirements are beyond the current state of the practice. If such a request is made by purchasers or installers, they should clearly communicate the requirements to the manufacturer or supplier during the contract decisions in order that disputes do not arise at a subsequent time.
TABLE 1 Minimum Types of Tests and Their Frequencies for the QC of GCLs
|Test Designation||Test Method||Frequency of Testing||Report Value|
| Free swell||D5890||Every 50 tonnes||Minimum average|
| Fluid loss||D5891||Every 50 tonnes||Minimum average|
|Geotextiles:|| || || |
| Mass per unit area||D5261||20 000 m2 (200 000 ft2)||Typical and MARV|
| Grab tensile strength (MD and CD)||D4632||20 000 m2 (200 000 ft2)||MARV|
|Geomembrane|| || || |
| Thickness||D5199||20 000 m2 (200 000 ft2)||MARV|
| Tensile strength at break and yield (MD and CD) C||D6693||20 000 m2 (200 000 ft2)||MARV|
|Finished GCL:D|| || || |
| Clay mass per unit area (dried)E||D5993||4000 m2 (40 000 ft2)||MARV|
| Clay moisture content||D5993||4000 m2 (40 000 ft2)||Average valueF|
| Tensile strengthG||D6768||20 000 m2 (200 000 ft2)||MARV|
| Bonding peel strength||D6496||20 000 m2 (200 000 ft2)||MARV|
| Index fluxB, G||D5887||Once weekly with the last 20 values reportedH||Maximum value|
A The tests on the bentonite are to be performed on the as-received material before fabrication into the GCL product.
B Cert letter from component manufacturer or QA from GCL manufacturer, or both. Cert letters must arrive and be checked before the components are used for the GCL production.
C For geofilms, Test Method D882 may be more appropriate.
D Components from finished GCL product should not be separated and tested, because the production process may alter the properties of the components.
E Dried bentonite should be defined as 0 % moisture content.
F Only for information.
G This test may not be applicable for geomembrane-backed GCLs.
H The last 20 values to be reported should end at the production date of the supplied GCL. If the manufacturer has more production facilities or production lines, or both, the tests must be performed and reported for each line.
1.1 This practice covers the manufacturing quality control of geosynthetic clay liners (GCLs), describing types of tests, the proper test methods, and the minimum testing frequencies.
1.2 This practice is intended to aid manufacturers, suppliers, purchasers and users of GCLs in establishing a minimum level of effort for manufacturing quality control.
1.3 This practice does not address manufacturing quality assurance, product acceptance testing, or conformance testing. These are independent activities taken by organizations other than the GCL manufacturer.
1.4 The values stated in SI units are to be regarded as the standard. The inch-pound units given in parentheses are for information only.
1.5 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 (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.
D882 Test Method for Tensile Properties of Thin Plastic Sheeting
D4439 Terminology for Geosynthetics
D4632 Test Method for Grab Breaking Load and Elongation of Geotextiles
D5199 Test Method for Measuring the Nominal Thickness of Geosynthetics
D5261 Test Method for Measuring Mass per Unit Area of Geotextiles
D5887 Test Method for Measurement of Index Flux Through Saturated Geosynthetic Clay Liner Specimens Using a Flexible Wall Permeameter
D5890 Test Method for Swell Index of Clay Mineral Component of Geosynthetic Clay Liners
D5891 Test Method for Fluid Loss of Clay Component of Geosynthetic Clay Liners
D5993 Test Method for Measuring Mass Per Unit of Geosynthetic Clay Liners
D6496 Test Method for Determining Average Bonding Peel Strength Between Top and Bottom Layers of Needle-Punched Geosynthetic Clay Liners
D6693 Test Method for Determining Tensile Properties of Nonreinforced Polyethylene and Nonreinforced Flexible Polypropylene Geomembranes
D6768 Test Method for Tensile Strength of Geosynthetic Clay Liners
Geosynthetic clay liner (GCL); Geosynthetics; Quality control (QC)--soil/related materials; 91.100.15 (Mineral materials and products)
ASTM International is a member of CrossRef.
Citing ASTM Standards
[Back to Top]