ASTM D5494-2018 pdf free download

ASTM D5494-2018 pdf free download.Standard Test Method for the Determination of Pyramid Puncture Resistance of Unprotected and Protected Geomembranes
1. Scope
1.1 The test method is to be used as an index test to determine the pyramid puncture resistance of geomembranes and, or both, geomembranes protected by nonwoven geotex- tiles and other puncture-protective geosynthetics. 1.2 The test method measures the increase of the pyramid puncture resistance due to the use of protective nonwoven geotextiles with geomembranes. 1.3 The values stated in SI units are to be regarded as the standard value. The values stated in parentheses are provided for information only. 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 appro- priate safety, health, and environmental practices and deter- mine the applicability ofregulatory limitations prior to use. 1.5 This international standard was developed in accor- dance with internationally recognized principles on standard- ization established in the Decision on Principles for the Development of International Standards, Guides and Recom- mendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
4. Summary of Test Method
4.1 A test specimen is clamped without tension between circular plates of a ring clamp attachment secured in a compression press or tensile testing machine. Aforce is exerted against the center of the unsupported or supported portion of the test specimen by a solid steel pyramid attached to a load indicator until rupture of the specimen occurs. The maximum load and elongation recorded is the value of the puncture resistance of the specimen.
5. Significance and Use
5.1 The pyramid method of puncture resistance is an index test for the determination of the puncture resistance of unpro- tected geomembranes or geomembranes protected with non- woven geotextiles and other puncture-protective geosynthetics. 5.1.1 The purpose ofthis test method is to establish an index value of puncture resistance by providing standard criteria and a basis for uniform reporting. 5.2 This test method may be used for acceptance testing of commercial shipments of geomembranes and geomembranes protected with nonwoven geotextiles; however, caution is advised since information about between-laboratory precision is incomplete.
6. Apparatus
6.1 Test Setup—A compression press with a reading force accuracy of at least 2 N (0.5 lb) is necessary. The press must maintain a constant test speed and should be provided with an automatic chart recorder for the force-versus-deformation be- havior. A clamping device for the test sample, a special piston, and electrical signal equipment for determining the puncture load are the additional pieces of test equipment needed. Also, a tensile testing machine conforming to the requirements of Specification D76/D76M can be utilized in a compression mode for this test method. The equipment setup shall provide a constant rate of speed, reading accuracy of at least 2 N (0.5 lb). and be provided with an automatic chart recorder for load versus deformation. Additional equipment required by this test method is described below. 6.2 Clamping Device—The upper and lower fixing ring clamp, dimensions ofwhich are shown in Fig. 1(a) and (b). The lower fixing ring shall be provided with a circular recess with a diameter corresponding to the external diameter of the compression base. This will facilitate mounting of the lower fixing ring to the compression base as illustrated in Fig. 2. Concentrically arranged grooves shall be located on the lower face of the upper ring and upper face of the lower ring to facilitate nonslip clamping of the test specimen(s). 6.3 Compression Base (Fig. 2)—CBR-type test presses are normally equipped with a CBR-cylinder compression base having a diameter of 150 mm (6.0 in.) as shown in Fig. 2. Additionally, the compression base must be deep enough to allow the loading piston to plunge at least 100 mm (4.0 in.). The compression base should be manufactured of rust- resistant, high-grade steel.