Significance and Use
4.1 This test method is applicable for testing GCCM materials in both a cured and uncured state. This determines the peel strength of various layers of these multilayer materials to determine critical interface strength. It is used with a constant rate of extension type of tensile testing machine.
4.2 The peel strength provides a measure of the strength of the connection between the top and bottom layers due to any linking elements present between them (such as connecting fibers/yarns or other linking elements), or the strength of the connection between the additional functional layers attached to the top or bottom layer that are necessary for the GCCM to function as a composite. In particular:
4.2.1 Uncured peel strength is important when installing a GCCM because the top and bottom layers must be securely connected in order to constrain the cementitious material when dragging/tensioning the GCCM into position. If the top/bottom layers become detached during handling, the cementitious material is no longer constrained and may overhydrate or can potentially fall or wash out from the GCCM, causing the set composite to have poor mechanical properties.
4.2.2 Cured peel strength is important in an installed GCCM because if the top layer is insufficiently attached it may become detached due to hydraulic shear or wind loads, or become completely detached and washed downstream, causing blockages and environmental damage. If the additional functional layers are poorly attached to the top/bottom/other additional functional layers, the layers may no longer act as a composite, which could lead to durability issues and multiple potential failure modes.
Scope
1.1 The purpose of this test method is to determine the peel strength of GCCM materials to include the various layers these multilayer materials possess. Both uncured and cured/hydrated materials are tested as a part of this method.
1.2 As an index 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.
