Comparative study of reverse catenary properties of the installation line for drag anchors

• New measurement techniques are developed to investigate the installation line embedded in soils.
• Comparative studies are performed between experiments, theoretical analysis and numerical simulations.
• Clear and full knowledge of reverse catenary properties of the embedded line is obtained.

The penetration mechanism and kinematic behavior of the drag anchor are significantly influenced by the installation line especially the segment embedded in seabed soils. Full knowledge of the embedded installation line is important to improving the drag embedment performance, predicting the trajectory, and solving the positioning problem in engineering. However, the configuration of the embedded line is complex and cannot be observed in soils. Few of the researchers performed systematic experiments focusing on the embedded line. Utilizing specially developed measurement techniques, four important topics including the reverse catenary profile of the embedded line, the effective length of the installation line, the relation between the vertical position and the drag angle at the shackle of the anchor, and the equivalent length of the installation line, are experimentally investigated in a model flume. Comparative studies of these topics are also performed between experiments, theoretical analysis and numerical simulations. Clear knowledge is then obtained which is beneficial to fully understanding complex properties of the embedded installation line.