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Simulation and tests with riveted CFRP sheets Investigating the joining of two CFRP fuselage shells using CFRP bolts, and the behaviour of such joins under cyclical stress. Goal: to determine the static strength and fatigue behaviour and thereby make recommendations for the use of CFRP joins. Bishop GmbH and project partner – the Institute for Polymer Composites at the Hamburg University of Technology – are investigating the joining of CFRP fuselage shells along with the strength and fatigue behaviour of CFRP laminates and their CFRP bolt joins. The use of CFRP bolts for the join is unique. The aim of the tests is to determine the extent to which the use of the same materials for joining is beneficial in comparison to the titanium bolts currently in use. Research is looking at both the static load-bearing behaviour of the CFRP bolts and the failure phenomenon of CFRP shells with reference to cyclical stress and static strength. Measurements are also being taken with the conventional titanium bolts in order to compare. To simplify the process, and above all to reduce costs, straight sheet strips are being used. The sheets are riveted in two rows, with one bolt at right angles to the load direction. Stress is applied cyclically in the pulsating tensile range. The common methods for simulating the behaviour under cyclical stress are to be used, allowing for recommendations to be made on the deployment of the technology. The damage which, of necessity, is caused during the tests is then evaluated in terms of the damage mechanism and its influence on the residual life of the joined shells. The laminates and the bolts are considered here. Contact Frank Nussbaeumer (TL), nussbaeumer.frank@bishop-gmb.com, +49 (0)40-866 258 10 Leadership Bishop GmbH Aeronautical Engnieers Partner Hamburg University of Technology, Institute for Polymer Composites (Dr Hans Wittich, +49 (0)40 42878 2633) Sponsored by Federal Ministry of Education and Research within the framework of the Leading-Edge Cluster strategy