Frictional dissipation in axially loaded simple straight strands

In this paper, an analytical investigation is made of the frictional dampin g properties of axially loaded metallic cables made from one layer of wires helically wrapped around a central wire. Our efforts are focused on the qu antity of energy dissipated through friction due to the motions between wir es when a cable is loaded. Although the local interwire pivoting drives the response of the cables studied, a first linear model is built where pivoti ng is allowed, but friction is not taken into account. Then, a law of frict ion is established and linearized to extend the linear model into a tractab le piecewise linear hysteretic one. Through a variety of examples, it appea rs that the energy dissipated in friction over a load cycle is very small c ompared to other sources of dissipation, because axially loaded simple stra ight strands do not experience fretting-induced failures, except close to t erminations. It is also shown that modifying the design of such cables is n ot expected to significantly improve their damping properties.