Comparative study of the service life of a central core and a helical strand constituting the same rope

Abstract

The purpose of this study is to characterize the mechanical behavior of the central core strand and of a helical strand taken from the same wire rope during the use. In addition, to predict the evolution of their damage and their instantaneous reliability. This is fulfilled by comparing the lifetime of the central core strand to as well as the helical strand based on static tensile tests performed on virgin specimen and others that are artificially damaged by breaking the wires making up the central core and the helical strand. Moreover, three damage models have been used to define the damage stages, from which, we can locate the critical life fraction βc in order to know which first element (centrale core strand or helical strand) will be broken. The intersection between the curve of damage and that of reliability enable us to find the element having the short lifetime.