Nonlinear static finite element analysis of sinking a floating pipeline to the bottom in calm water

摘要

This paper describes a nonlinear static finite element analysis for simulating a process of submerging a floating pipeline to the bottom in calm water. Soil-pipe interaction elements, fully submerged pipe elements, partially submerged pipe elements, and floating pipe elements were used. Also, a load stiffness matrix associated with hydrostatic pressure was illustrated. Then, an incremental iterative procedure was developed to analyze large deformation of the pipeline during the sinking process and to take into account pipe-seabed interaction. The paper concentrates on the modeling of filled-in water loads and boundary conditions related to an offshore tugboat. Some numerical examples are provided to show the capabilities of the proposed analysis to model the continuous float-and-sink procedure of the pipeline.