4. Compression fatigue

Unlike metallic materials, which suffer little or no damage in compression, all composite materials subjected to monotonic or cyclic loading have a different resistance to tensile loading. This fact makes compression testing essential. Compressive fatigue tests on plates are difficult to perform. In order to avoid generalized buckling of the laminated plate under test, the standards propose various set-ups, the principle of which is illustrated in the diagrams in Fig. 20