【国外标准】 Standard Test Method for Large-Scale Hydrostatic Puncture Testing of Geosynthetics

4.1 Procedure A—This procedure is an index-type test which can be used as a guide for acceptance of commercial shipments of geosynthetics. The standard cone and pyramid test fixtures can establish critical height (ch) consistency with similar material from previous lots or different suppliers, as well as testing from other laboratories. However, due to the time required to perform tests, it is generally not recommended for routine acceptance testing.4.2 Procedures B and C—These procedures are performance tests intended as a design aid used to simulate the in-situ behavior of geosynthetics under hydrostatic compression. These test methods may assist a design engineer in comparing the ability of several candidate geosynthetic materials to conform to a site-specific subgrade under specified use and conditions. In procedure B, the pressure is increased until a failure is observed. In procedure C, a given set of conditions (pressure, temperature and test duration) are maintained constant and the performance of the system is observed at the end of the test.1.1 This test method evaluates the stress/time properties of geosynthetics by using hydrostatic pressure to compress the geosynthetic over synthetic or natural test bases consisting of manufactured test pyramids/cones, rocks, soil, or voids.1.2 This test method allows the user to determine the relative failure mode or points of failure for geosynthetics, or both.1.3 This test method offers two distinct procedures:1.3.1 Procedure A incorporates manufactured test pyramids or cones as the base of the testing apparatus. Procedure A is intended to create comparable data between laboratories, and can be used as a guide for routine acceptance tests for various materials.1.3.2 Procedures B and C incorporate site-specific soil or other material selected by the user as the test base of the testing apparatus. Procedures B and C are methods for geosynthetic design for a specific site.1.4 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.1.5 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 appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. For a specific warning statement, see Section 6.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.