A global-local approach to predict the fretting-fatigue failure of clamped aluminum powerline conductors: From mono-contact crossed wires to full conductor vibrational tests

This work focuses on a multiscale analysis of the fretting-fatigue endurance of aluminum strands within overhead conductors. Based on experimental results, Crossland, Fatemi Socie and SWT fatigue criteria were applied using a Finite Element Method (FEM) modeling. These were used with the critical distance method calibrated on the fretting-fatigue failure of crossed monocontact strands. With this strategy, the SWT criterion gave the best lifetime estimates as well as the shorter critical distance. By conducting a stress gradient analysis, it is concluded that the shorter the critical distance, the better the contact stress description and finally the better the prediction. This optimized critical distance - stress gradient strategy is then transposed to the complete 3D simulation of a complete multi-strand cable structure subjected to vibrational bending loadings. The comparison with real structural tests confirms the capacity of the proposal to estimate the fretting-fatigue risk.