Tensile fatigue behaviour of FRP and hybrid FRP sheets

This paper presents the fatigue behaviour of various fibre reinforced polymer (FRP) composites, namely, carbon, glass, polyparaphenylenl benzobisoxazole (PBO), and basalt fibres, including the effect of hybrid applications such as carbon/glass and carbon/basalt composites. A coupon test was conducted to examine the mechanical characteristics of the FRP composites subjected to monotonic and cyclic loads. Test parameters included the applied load range and different types of hybridization. Study results show that (1) the mechanical properties of the emerging PBO and basalt fibres are comparable to those of the conventional carbon and glass fibres; (2) the tensile modulus of the fibres influences the failure mode of the composite coupons; (3) the progressive damage propagation causes fatigue failure of the composites; (4) the hybrid composites of carbon/basalt significantly improves the fatigue resistance in comparison to the homogeneous basalt composite, whereas the resistance of the carbon/glass hybrid composites does not provide such effects.