ASTM D8480-23 PDF

SIGNIFICANCE AND USE 4.1 This test method is applicable for testing GCCMs in the cured state. This determines the initial and final breaking load to determine the initial and final tensile strength of the GCCM. It is used with a constant rate of extension type tensile testing machine. 4.2 GCCMs are composites, and the cured cementitious material typically has a lower tensile strength to the geosynthetic layer(s). When testing the tensile strength of a cured GCCM, multiple cracks will typically form in the cementitious material, transferring loads to the reinforcing fibers (or linking elements) before the ultimate tensile strength of the GCCM is reached. In certain applications, engineers need to know the initial tensile strength of the GCCM, which is when the cementitious material first breaks and the material’s rigidity is reduced, not just the final tensile strength (ultimate strength), which is governed primarily by the geosynthetic layer(s). 4.3 In service, the top layer of geosynthetic in a GCCM is particularly exposed to degradation from UV exposure and abrasion, especially in erosion control applications such as for channel lining with high levels of sedimentation in water flow. It is important that reported values take account of the effects of environmental degradation where this has a significant effect on in-service performance. It is therefore also necessary to test the initial and final tensile strength of the GCCM when the top layer has been removed to provide an indication of long-term GCCM tensile performance. SCOPE 1.1 The purpose of the proposed test method is to determine the tensile strength of cured/hydrated GCCM materials to include reporting the initial tensile strength (first crack in the cementitious layer) and final tensile strength for GCCMs as supplied and in a weathered state with the geosynthetic top layer(s) removed. 1.2 As a performance test, this method will be used relatively infrequently and to test large lots of material. This test is not intended for routine quality control testing of GCCMs. 1.3 The values in SI units are to be regarded as the standard. Values in inch-pound units are in parentheses for information. 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 appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.5 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.