DRY FRICTION LOSSES IN AXIALLY LOADED CABLES

A model of a cable comprising interacting wires with dry friction forc es at the interfaces is subjected to a quasi-static cyclic loading. Th e first cycle of this process, comprising of axial loading, unloading and reloading is investigated analytically. Explicit load-elongation r elationships are obtained for all of the above phases of the cycle. An expression for the hysteretic losses is also obtained in an explicit form. It is shown that losses are proportional to the third power of t he amplitude of the oscillating axial force, and are in inverse propor tion to the interwire friction forces. The results obtained are used t o introduce a model of a cable as a solid rod with an equivalent stiff ness and damping properties of the rod material. It is shown that the stiffness of the equivalent rod is weakly nonlinear, whereas the visco us damping coefficient is proportional to the amplitude of the oscilla tion. Some numerical results illustrating the effect of cable paramete rs on the losses are given.