Abstract
Results of zero-tension fatigue tests are presented for flat sheet unidirectional 0° and angle-plied +/-45° carbon fibre reinforced plastics. Torsional-shear and transverse fatigue tests were made on hoop-wound tubes. These have shown that surface finish has a significant role in determining the fatigue performance of CFRP.A method is presented for assessing the fatigue stress bandwidth in zero-tension fatigue at 0° CFRP. A mechanism of fatigue failure in 0° CFRP is also postulated. Fatigue induced creep effects were observed during shear loadings and these are shown to relate to cracking and crack growth in +/-45° material. A shell theory analysis of tubular CFRP test-pieces was made which demonstrates the suitability of this specimen for 0° longitudinal and 90° hoop-windings. Hoop-wound tubes were used to show that the mutual interactions between shear and transverse elastic properties are not significantly affected by transverse fatigue stresses.