Estimation of Submarine Cable Burial Depth using CBRA Model

Abstract

Submarine cable plays an important role in land-island power supply, and domestic and overseas communication. However, damages to the submarine cable have been caused by various dangerous factors such as ship anchors and trawlers. Even though the annual cost for recovering submarine cables is enormous, there is no definite method for protecting submarine cables. The present study investigates the applicability of Cable Burial Risk Assessment (CBRA) model to the estimation of the burial depth of submarine cables. This technique employs a statistical approach to the marine environment of the target area and the navigation data of nearby passing ships. Two computer programs have been developed to facilitate the calculations of anchor penetration depths in clay and sand, respectively. An example application of CBRA model was demonstrated here taking a tentative cable route to Haenam - Jeju sea area. The cable burial depth was calculated to vary from a minimum of 0.6m to a maximum of 0.74m for a 2500 year return period and a minimum of 0.6m to a maximum of 1.40m for a 25,000 year return period. This study also determined the target ship weight in the CBRA model through the statistical expectation. The expected cable burial depth appeared from a minimum of 0.6m to a maximum of 1.26m.