Behaviour of embedded anchor chains

PhD student

Wenlong Liu

Supervisors

Prof Yinghui Tian	Prof Mark Cassidy

Project Details

Offshore floating facilities are required to be secured through a mooring system, which comprises anchors and mooring lines. The segment of the mooring line, predominately using metallic chain, is embedded in the soil to connect the embedded anchor and takes a reversed catenary shape. The friction capacity of the anchor line itself can take up a major component of the overall anchor capacity. The bearing capacity of embedded anchors is controlled by the chain inclination and depth at the padeye. Most of existing research and current design practices consider the anchor line profile in a two-dimensional vertical plane. The friction and normal soil resistance to the anchor chain are not coupled in the existing analytical design method of embedded anchor line.

The aim of this research is to gain in-depth knowledge about the soil resistance to the chain links and advance the fundamental understanding of three-dimensional performance of the embedded anchor line. This research mainly uses numerical simulation method to investigate the bearing capacity and combined yield surface of the chain link. A new numerical approach based on a force-resultant macroelement plasticity model will be developed to implement three-dimensional analysis of the anchor line.