ASTM D7956/D7956M : 16(2024)

1.1 This practice covers an approach for compressive testing thin damaged multidirectional polymer matrix composite laminates reinforced by high-modulus fibers using a sandwich long beam flexure specimen. It provides a test configuration in which the core does not constrain any protruding back side damage. It is limited to testing of monolithic solid laminates which are too thin to be tested using typical anti-buckling fixtures. It does not cover compressive testing of damaged sandwich panel facings. The composite material forms are limited to continuous-fiber or discontinuous-fiber (tape or fabric, or both) reinforced composites in which the laminate is balanced and symmetric with respect to the test direction

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.

1.3 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.

1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International StandardDetails, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.