The focus of this research is the investigation of the fatigue behaviour of unidirectional 3D-printed continuous carbon fibre reinforced polymer (CFRP) tension straps with polyamide matrix. Conventionally produced tension straps are established components in the mechanical as well as the civil engineering sector (e.g. rigging systems for sailing boats, cranes and first bridges). All the structures mentioned above are subjected to high fatigue loads and although it is commonly reported that carbon fibre reinforced polymers show excellent fatigue resistance, there is limited understanding about the behaviour of CFRP loop elements under such loads, especially in combination with fretting at the attachment points. Research on this topic was performed at Empa in the past decade with thermoset CFRP straps, but never with 3D-printed continuous CFRP straps with thermoplastic matrix. Preliminary results are presented in this master thesis, which show that the fatigue endurance limit for investigated 3D-printed CFRP strap design is acceptable, when compared to steel tendons. However, it is still 8 % lower than conventionally produced CFRP straps using out-of-autoclave unidirectional carbon fibre prepregs. Reasons for this and potential future improvements are discussed.
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