Active Standard ASTM D7406 | Developed by Subcommittee: D35.02
Book of Standards Volume: 04.13
Historical (view previous versions of standard)
Significance and Use
5.1 The performance characteristics of a drainage geosynthetic are directly related to the integrity under compressive loading. If the product is sensitive to compressive creep, its flow capacity could be greatly reduced or even shut off completely.
5.4 Compression creep as it relates to reduction in flow capacity of a geosynthetic drainage product is manufacturer and product specific. For example, a 10% reduction in original thickness of a geonet made by manufacturer A does not necessarily equal the same reduction in flow capacity as a 10% reduction in thickness of the same or another type of geonet made by manufacturer B.
5.5 This creep data has is merit directly to the end user, because it can be easily interpreted to result into a reduction factor for creep3 . The Reduction factor can then be used to derive an allowable flow rate4.
1.1 This test method is used to determine the unconfined compressive creep characteristics of drainage geotextiles, geocomposites, geonets, or any other geosynthetic associated with drainage at a constant temperature, when subjected to a constant compressive stress.
1.2 This test method is intended for use as an unconfined compressive performance creep test only. For a detailed procedure on how to establish an index test see the EN standard 1897. For performance tests, the specimen shall be subjected to the site-specific liquid and/or the site-specific stress (normal and potentially shear stress).
1.3 Because of the changing nature of the geosynthetic industry, and the wide variety of products already available, this particular test method may have to be slightly modified for unconfined compression creep testing of some products..
2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.
D2990 Test Methods for Tensile, Compressive, and Flexural Creep and Creep-Rupture of Plastics
D4439 Terminology for Geosynthetics
D5199 Test Method for Measuring the Nominal Thickness of Geosynthetics
D5261 Test Method for Measuring Mass per Unit Area of Geotextiles
D5262 Test Method for Evaluating the Unconfined Tension Creep and Creep Rupture Behavior of Geosynthetics
D6364 Test Method for Determining Short-Term Compression Behavior of Geosynthetics
ICS Number Code 59.080.70 (Geotextiles)