ASTM D7747/D7747M-11(2018)

4.1 The use of reinforced geomembranes as barrier materials has created a need for a standard test method to evaluate the quality of seams produced by thermo-fusion methods. This test method is used for quality control purposes and is intended to provide quality control and quality assurance personnel with data to evaluate seam quality.

4.2 This standard arose from the need for a destructive test method for evaluating seams of reinforced geomembranes. Standards written for destructive testing of nonreinforced geomembranes do not include all break codes (Fig. 1) applicable to reinforced geomembranes.

4.3 When reinforcement occurs in directions other than machine and cross-machine, scrim are cut at specimen edges, generally lowering results. To partially compensate for this, testing can be performed according to Test Method D7749, or the 2-in. wide strip specimen specified in this method can be utilized. Testing of 1-in. and 2-in. specimens is Method A and Method B, respectively.

4.4 The shear test outlined in this method correlates to strength of parent material measured according to Test Method D7003/D7003M only if reinforcement is parallel to TD. For other materials, seam strength and parent material strength can be compared through Test Methods D7749 and D7004/D7004M. Values obtained with the strip methods shall not be compared to values obtained with grab methods.

1.1 This test method describes destructive quality control tests used to determine the integrity of thermo-fusion seams made with reinforced geomembranes. Test procedures are described for seam tests for peel and shear properties using strip specimens.

1.2 The types of thermal field and factory seaming techniques used to construct geomembrane seams include the following:

1.3 The types of materials covered by this test method include, but are not limited to, reinforced geomembranes made from the following polymers:

1.4 Units—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 nonconformance with the standard.

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.