Improvement of seabed cable plough tow force prediction models

Abstract

As the use of offshore renewable energy sources such as wind and wave energy systems expands, they represent an increasing portion of the energy mix. Subsea cables connecting these resources are subject to many hazards, making cable burial using cable ploughing an important tool in preventing unplanned outages and downtime. This represents a significant installation cost for offshore renewables and there is a need to improve the accuracy of tow force, plough speed predictions and final burial depth of the cable. These are currently made using semiempirical models as the large soil displacements involved cause instabilities in the finite element analysis. This paper provides an overview of work to develop new material point method numerical software to allow cable ploughing to be analysed and optimised. The focus of this paper is the physical modelling carried out to provide validation of the software, which includes both 1g and centrifuge testing, as well as considering interim ways to improve the existing semi-empirical models.