|Geomembrane Committee Addresses Integrity of Seams in New Standard
The increased use of geomembranes as barrier materials to restrict liquid migration from one location to another created a need for a test method to evaluate the quality of geomembrane seams produced by tape methods. ASTM Committee D35 on Geosynthetics has met this need with the approval of the new standard D 7272, Test Method for Determining the Integrity of Seams Used in Joining Geomembranes by Pre-manufactured Taped Methods. The standard is under the jurisdiction of Subcommittee D35.10 on Geomembranes.
“As the magnitude and visibility of the projects that incorporate geomembranes with taped seams increased, it became apparent that engineers wanted an internationally recognized standard to determine the quality of the seams being made in the field,” says Jeff PanKonie, senior sales engineer, Firestone Specialty Products. While taped seams had been tested according to D 4437, Practice for Determining the Integrity of Field Seams Used in Joining Flexible Polymeric Sheet Geomembranes, PanKonie notes that the new test method D 7272 more accurately addresses the unique characteristics of taped seams.
Test Method D 7272 was developed to be used with most taped seams, whether the membrane is reinforced or non-reinforced. The standard also has allowances for seam width, since seams can vary greatly with taped products dependent on the manufacturer and the types of membrane and taped seam.
PanKonie says that D 7272 will become a reference for engineers designing projects with taped seams, as well as for contractors who can use the standard for field testing. In addition, laboratories will be able to use the new test method to determine if field seams using taped products meet minimum requirements established by design engineers. Using the standard to record and report data such as separation that occurs during the peel test and elongation during the shear tests will allow quality assurance engineers to repair inferior seams during construction, thus minimizing the potential for seam separation while in service.
Interested parties are invited to participate in the standards developing activities of Subcommittee D35.10.
Technical information: Jeff PanKonie, Firestone Specialty Products,
ASTM Staff: Christine Sierk
Jan. 31-Feb. 2, 2007
January Committee Week
Costa Mesa, Calif.