【国外标准】 Standard Test Method for Evaluating the Adhesion (Pull-Off) Strength of Concrete Repair and Overlay Mortar

5.1 When the test is performed on the repair or overlay material, the result is the bond strength to the concrete panel or the tensile strength of either the overlay or concrete panel, whichever is weaker.5.2 The measured strength is controlled by the failure mechanism requiring the least stress. Thus, it is not possible to know beforehand which strength will be measured by the test. For this reason, the failure mode has to be reported for each individual test result, and tests results are averaged only if the same failure mode occurs. Alternatively, one can infer that the bond strength is greater than the failure stress if the bond does not fail during the test.5.3 The method may also be used to evaluate the performance of bonding agents.5.4 This test method is designed to evaluate bond strengths in the laboratory and to standardize conditions that permit comparison of results between laboratories. It is not intended to determine bond strength for field applications as results obtained are only applicable to the standard substrate.1.1 This test method is suitable for laboratory use to determine one or more of the following:1.1.1 The bond strength of a repair or an overlay material to a specific concrete substrate.1.1.2 The tensile strength of a repair or overlay material after the material has been applied to the concrete substrate.1.1.3 The change in bond strength when applying a bonding agent or other bond modifying treatment to the concrete substrate.1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined. Some values have only SI units because the inch-pound equivalents are not used in practice.1.2.1 If required results obtained from another standard are not reported in the same system of units as used by this test method, it is permitted to convert those results using the conversion factors found in the SI Quick Reference Guide.21.3 The text of this test method refers to notes and footnotes that provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of this test method.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. (Warning—Fresh hydraulic cementitious mixtures are caustic and may cause chemical burns to skin and tissue upon prolonged exposure.)31.5 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.