Standard Test Method for Compressive Residual Strength Properties of Damaged Sandwich Composite Panels

Importancia y uso:

5.1 Susceptibility to damage from concentrated out-of-plane forces is one of the major design concerns of many structures made of sandwich constructions. Knowledge of the damage resistance and residual strength properties of a sandwich construction is useful for product development and material selection.

5.2 The residual strength data obtained using this test method is most commonly used in material selection, research and development activities, and establishing design allowables.

5.3 The properties obtained using this test method can provide guidance in regard to the anticipated residual strength capability of sandwich constructions of similar facesheet and core material, adhesive, facesheet and core thickness, facesheet stacking sequence, and so forth. However, it must be understood that the residual strength of sandwich constructions is highly dependent upon several factors including geometry, thickness, stiffness, support conditions, and so forth. Significant differences in the relationships between the damage state and the residual compressive strength can result due to differences in these parameters.

5.4 The compression strength from this test may not be equivalent to the compression strength of sandwich structures subjected to flexural compression testing.

5.5 The reporting section requires items that tend to influence residual compressive strength to be reported; these include the following: facesheet and core materials, core density, cell size and wall thickness if applicable, film adhesive, methods of material fabrication, accuracy of lay-up orientation, facesheet stacking sequence and thickness, core thickness, overall specimen thickness, specimen geometry, specimen preparation, specimen conditioning, environment of testing, type, size and location of damage (including method of non-destructive inspection), specimen/fixture alignment and gripping, time at temperature, and speed of testing.

5.6 Results from the residual strength assessment include the following: normalized compressive residual strength N^CAI, compressive force as a function of crosshead displacement, and far-field surface strains as functions of crosshead displacement.

Subcomité:

D30.09

Referida por:

D4762-23, D7766_D7766M-23

Volúmen:

15.03

Número ICS:

83.120 (Reinforced plastics)

Palabras clave:

composite materials; compression after impact; compressive residual strength; compression testing; residual strength; sandwich composites; sandwich construction;