A model of a simplified single-layer stranded cable is developed to compute the bending energy dissipated by friction between strand components and to compare it to the experimental values derived from tests on overhead transmission line conductors in free-field condition. It is assumed that wire-core contact exists and that wire-wire contact in the layer, if ever present, is frictionless. Wire diameter is small compared to core diameter, and an uniform axial stress state is assumed. The relative displacement between wire and core is determined according to the theory of contact mechanics. Two types of strand deflections are examined: (1) Uniform curvature; or (2) sinusoidal deflections. The energy dissipated by friction is computed on the basis of two regimes: (1) Partial slip; and (2) gross sliding regimes. The theoretical dissipated energy results are provided on a parametric basis and are compared to the results of two models using “rigid-plastic” Coulomb friction law.
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