Stress relaxation behavior and its effect on the mechanical performance of a wire cable

Aiming at solving the failure problems of a wire cable caused by stress relaxation, the stress relaxation behavior of a wire cable under axial tensile load is investigated based on the elastic theory and creep theory. The Poisson's ratio effect is considered in the multilayer contact analysis between the neighboring wires of the rope. A finite element model for the axial mechanical property and stress relaxation performance between the wires of the cable is established. The model is verified and validated by comparison with published data. The results show that the stress relaxation leads to low contact stress which leads to reduced rate of relaxation in the wire cable. With the increase of the lay angles of the spiral wires, the contact pressures between different layers of the cable increase, while the stress relaxation behavior reduces the effect to a certain extent. Compared with the lay angle of the intermediate layer, the lay angle of the outer layer has more pronounced effect on the stress relaxation of the rope. The decreasing of the elastic modulus and increasing of the Poisson's ratio of the wire material help to reduce the stress relaxation and creep strain of the wire cable.