ASTM D7056-07(2012)

The use of PBGM as barrier materials to restrict liquid migration from one location to another in soils has created a need for a standard test method to evaluate the quality of PBGM seams. In the case of PBGM, it has become evident that seams can exhibit separation in the field under certain conditions. Although this is an index type test method used for quality assurance and quality control purposes, it is also intended to provide the quality assurance engineer with sufficient seam shear data to evaluate seam quality. Recording and reporting data will allow the quality assurance engineer to take measures necessary to ensure the repair of seams with unacceptable strength during facility construction, and therefore, minimize the potential for seam separation in service.

1.1 This test method presents the procedures used for determining the quality of prefabricated bituminous geomembrane (PBGM) bonded seams subjected to a shear test. It describes a destructive quality control test used to determine the integrity of PBGM seams.

1.2 This test procedure is intended for PBGM only.

1.3 The type of thermal field seaming technique used to construct PBGM seams include the following.

1.3.1 Torch-on—This technique melts two PBGM surfaces to be seamed by running a flame from a propane torch between them. Pressure is applied on the top or bottom, or both PBGM, forcing together both surfaces to form a continuous bond.

1.3.2 Hot Air—This technique introduces high-temperature air or gas between two PBGM surfaces to facilitate melting. Pressure is applied on the top or bottom, or both PBGM, forcing together both surfaces to form a continuous bond.

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.