Time-varying dynamic performance of a floating platform-mooring system based on the mechanical experimental data derivation method for corroded wire ropes

Abstract

Wire ropes that are used for long periods in harsh marine environments inevitably suffer corrosion damage, which degrades their mechanical properties and affects the safety of floating platforms. To better analyse this, the mechanical properties of corroded wire ropes are simulated in this study using experimental data derivation and section reduction methods. The differences between the two simulation methods were compared, and the effects of the corrosion of wire ropes on the motion response and safety of the floating platform were investigated. The experimental data of tensile cyclic mechanical properties of corroded wire ropes were used to derive the change law of mechanical characteristics of wire ropes with specific service life. The hydrodynamic model of a typical floating platform was established, and the corroded floating platform-mooring system was subjected to a time-domain coupled analysis. The results indicate that the platform motion response based on the experimental data derivation method is significantly greater than that obtained from the section reduction method. This implies that the section reduction method may underestimate the damaging effect of corrosion on the mechanical properties of wire ropes, whereas the experimental data derivation method can reflect the time-varying safety of long-term service floating platforms more realistically.