Destructive testing of polyethylene geomembrane seams: Various methods to evaluate seam strength

The incidence of high-density polyethylene geomembrane liner failures makes it essential that as much information as possible regarding seam performance be extracted from testing. The durability of polyethylene geomembrane seams can be determined largely by the data resulting from conventional seam peel and shear destructive tests.

Unfortunately, current test parameters and acceptance criteria are not used to a great enough extent. Specifically, the seam peel and shear tests can and should be used more fully to assess the effect of seaming on the strength and durability of the seam and the adjacent geomembrane. Specific minimum values for seam shear strength and elongation as well as peel separation should be established by a project's geosynthetic design engineer. In addition, functional seam test acceptance criteria for very low-density polyethylene need to be defined. Another type of testing that can provide valuable information on the aging behavior and defect distribution within field seams is hydrostatic, biaxial burst testing.