A concise finite element model for three-layered straight wire rope strand

A concise finite element model (FEM) of three-layered straight helical wire rope strand under axial loads (tensile and torsional) is presented in this paper. Three-dimensional solid elements were used for structural discretiz ation. The helical symmetry of the strand was used to establish accurate bo undary conditions. Contact, friction and plastic yielding were also taken i nto account. For the global behaviour of wire rope strand, i.e. load vs. st rain and load vs. torque (fixed-end) or load vs. strand twist rate (free-en d), the finite element results showed better agreement with the experimenta l results of Utting and Jones (Journal of Strain Analysis for Engineering D esign 1988;23(2):79-86) than those calculated using the analytical strand m odel of Costello (Theory of Wire Rope, 2nd ed. New York: Springer, 1997). I n addition, the FE model allows the localised stress distribution to be det ermined. In particular, this model reveals the non-uniform stress distribut ion in the outer layer helical wires caused by the trellis point contact. T his is particularly relevant in the fixed-end case, where the present analy sis predicts an axial tensile rigidity in good agreement with the experimen tal observations (Utting and Jones), whereas Costello's model predicts a si gnificantly higher rigidity. (C) 1999 Elsevier Science Ltd. All rights rese rved.