Standard Practice for Flexural Residual Strength Testing of Damaged Sandwich Constructions

Importancia y uso:

5.1 This practice provides supplemental instructions that allow the use of Test Method D7249/D7249M to determine residual compressive or tensile strength properties of damaged sandwich constructions. Susceptibility to damage from concentrated out-of-plane forces is one of the major design concerns of many structures made using sandwich constructions. Knowledge of the residual strength properties of a sandwich panel is useful for product development, establishing design allowables, and material selection.

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

5.3 The properties obtained using this test practice can provide guidance in regard to the anticipated compressive or tensile 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 or tensile 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 pure edgewise (in-plane) compression.

5.5 The reporting section requires items that tend to influence residual 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, time at temperature, and speed of testing.

Subcomité:

D30.09

Referida por:

D8287_D8287M-22, D4762-23, D7766_D7766M-23

Volúmen:

15.03

Número ICS:

91.080.99 (Other structures)

Palabras clave:

core; damage resistance; damage tolerance; delamination; dent; disbond; drop-weight impact; facesheet; impact testing; quasi-static indentation; sandwich; sandwich construction;