2. Introduction

Pulleys are used, during the construction of aerial power lines, for the operation of laying cables. The cable during installation [Figure 2-a] is fixed to one of the stop supports of the canton, it rests on pulleys placed at the bottom of the insulators of the alignment supports and it is retained by a force at the level of the second stop support. By playing on this force - or by moving its point of application - we adjust the arrow of one of the ranges, the one that is most subject to environmental constraints. Then the pulleys are removed and the cable is fixed to the insulators. The length of the cable in the various ranges is then fixed and it determines the subsequent behavior of the line under static stresses (wind, frost overload) and under dynamic conditions (movement due to Laplace forces created by short-circuit currents).

Figure 2-a: Laying a cable in a two-span town

The finite cable-pulley element presented here makes it possible to model the installation operation and therefore to calculate, in a natural way, the cable length in the various spans.

The idea for this finite element came to us some time after the conversation [bib1] and we presented its formulation in [bib2].