A parametric study on the structural damping of suspended cables

The maximum expected amplitude of aeolian vibration is commonly evaluated, in overhead power lines, by the Energy Balance Principle. Within this approach empirical power laws are used to express energy dissipation, and usually require experimental tests to define their coefficients. Starting from a previous formulation for the hysteretic bending of overhead electrical lines, the authors propose first a unified non-dimensional expression for the dissipated energy per unit of length of ACSR conductors, and, second, a closed form expression of the upper-bound estimate of the cable self damping. The proposed self-damping model is applied to the aeolian vibrations of a full-scale experimental test span comparing the predictions with application of the empirical power laws and with experimental data. The results highlight the paramount role played by the self damping model.