Algorithmic formulation of clay and sand pipe–soil interaction models for on-bottom stability analysis. (July 2021)

• Record Type: Journal Article
• Authors: Longva, Vegard; Ji, Guomin; Sævik, Svein; Ye, Naiquan; Gjøsteen, Janne K.Ø.; Giertsen, Egil; Wang, Yanbin
• Is Part Of: Marine structures. Volume 78(2021)
• Publication Date: 2021-07
• Subjects: Pipe–soil interaction -- On-bottom stability -- Elasto-plastic -- Algorithmic optimization -- Backward-Euler update algorithm; Naval architecture -- Periodicals; Offshore structures -- Periodicals; Architecture navale -- Périodiques; Structures offshore -- Périodiques; Naval architecture; Offshore structures; Periodicals; 620.4162
• DOI: 10.1016/j.marstruc.2021.102985
• Languages: English
• ISSNs: 0951-8339

Abstract

Abstract: This paper presents a new algorithmic formulation of the clay and sand pipe–soil interaction models recommended by the DNV-RP-F109 code for dynamic on-bottom stability analysis of submarine pipelines. The pipe–soil force update algorithm is formulated within the framework of computational elasto-plasticity and applies Backward-Euler integration to ensure stability and robustness for large time step sizes. Algorithmic optimization techniques are developed by utilizing a closed-form solution and subincrementation. A numerical verification study covering full cyclic displacement ranges of a 12 inch pipeline is presented. The new formulation is shown to increase the time step size by a factor of up to 50 compared to commercial software tools for on-bottom stability analysis. This achievement will be particularly beneficial for long-duration 3D nonlinear time domain on-bottom stability analysis. Highlights: A new algorithmic formulation for cyclic pipe–soil interaction models is presented. 50 times larger time steps compared to existing software tools can be applied. A closed-form solution for boosting the numerical efficiency is developed. Pipeline on-bottom stability can now be based on nonlinear 3D time-domain analysis. Implementation details for state-of-the-art pipe–soil interaction models are given.