【国外标准】 Standard Practice for Quality Control of Geosynthetic Clay Liners

4.1 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.MD = machine direction.    CD = cross-machine direction.    Minimum = lowest result for the produced lot from which the supplied rolls were selected.    Maximum = highest result for the produced lot from which the supplied rolls were selected.    n/a = not applicable.(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) If the moisture content from the bentonite added during production did not change, the mass per unit area and moisture content of the bentonite (evaluated according to 1.3 in Table 1) can be used to determine the values of the finished GCL product.(D) Components from finished GCL product should not be separated and tested, because the production process may alter the properties of the components.(E) MARV–minimum average roll value, only evaluated for a one-year production period with an average value minus 2 standard deviations. If the production period is less than one year, for example, for job-specific products, a MARV value may not be able to be evaluated, then the minimum value shall be reported.(F) Dried bentonite should be defined as 0 % moisture content.(G) Internal shear testing (Test Method D6243/D6243M) may be applicable to quality control of the bonding strength of non-needle-punched reinforced and stitch-bonded GCLs.(H) This test is not applicable for multi-component GCLs (for example, products with geomembrane backing(s), geofilm backing(s), or polymer backing(s)).4.2 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.4.3 It should also be recognized that purchasers and installers of GCLs may require additional tests or greater frequencies 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.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 either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.