Energy method for experimental life prediction of central core strand constituting a steel wire rope

Abstract

Abstract This study is an attempt to predict the evolution of damage in a central core constituting a steel wire rope of 19 × 7 non-rotating type, using the energy of rupture determined by the method of a numerical trapezoidal rule of a discreet function. The numerical integral used here is based on the experimental results of simple tensile tests carried out on virgin and artificially damaged specimens, breaking the wire constituting specimens at different percentages. The results obtained made it possible to evaluate the energy behavior of the central core subjected to static loads and subsequently to predict the evolution of the damage. Indeed we were able to determine three stages of damage that allowed us to predict its earlier stages then the moment of its acceleration where a predictive maintenance is required as well as the critical life fraction which can lead to the failure of strand. The present study also includes a comparison between two approaches of calculating damage: The static damage consists in tracking the evolution of the energy at different percentages of the life of the test specimen. The second approach of damage is based on the reduction of the energy, and the energy corresponds to endurance limit of damage strand according to the unified theory. These techniques can help the industrials to have anticipatory maintenance strategy and an awareness the safety requirements.