5.1 The procedure described in this test method for determination of the shear resistance of the soil and geosynthetic or geosynthetic and geosynthetic interface is intended as a performance test to provide the user with a set of design values for the test conditions examined. The test specimens and conditions, including normal stresses, are generally selected by the user.

5.2 This test method may be used for acceptance testing of commercial shipments of geosynthetics, but caution is advised as outlined in 5.2.1 .

5.3 The test results can be used in the design of geosynthetic applications, including but not limited to: the design of liners and caps for landfills, mining heap leach pads, tailings impoundments, cutoffs for dams and other hydraulic barriers, geosynthetic-reinforced retaining walls, embankments, and base courses; in applications in which the geosynthetic is placed on a slope; for determination of geosynthetic overlap requirements; or in other applications in which sliding may occur between soil and a geosynthetic or between two geosynthetic materials.

5.4 The displacement at which peak strength and post-peak strength occurs and the shape of the shear stress vs. shear displacement curve may differ considerably from one test device to another due to differences in specimen mounting, gripping surfaces and material preparation. The user of results from this standard is cautioned that results at a specified displacement may not be reproducible across laboratories and that the relative shear displacement measured in this test at peak strength may not match relative shear displacement at peak strength in a field condition.

1.1 This test method covers a procedure for determining the shear resistance of a geosynthetic against soil, or a geosynthetic against another geosynthetic, under a constant rate of deformation.

1.2 The test method is applicable for all geosynthetics, with the exception of geosynthetic clay liners (GCLs) which are addressed in Test Method D6243 .

1.3 The test method is not suited for the development of exact stress-strain relationships for the test specimen due to the non-uniform distribution of shearing forces and displacement.

1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.

1.5 This standard does not purport to address all 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.