An integrated finite element method model for wave-soil-pipeline interaction

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Zaibin Lin, Yakun Guo, Dong-Sheng Jeng, Nick Rey, Chengcong Liao

Monday 29 june 2015

16:15 - 16:30h at Amazon (level 1)

Themes: (T) Water engineering, (ST) River and coastal engineering

Parallel session: 3C. Coastal engineering

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In this study, a monolithically integrated Finite Element Method (FEM) model has been developed for wave-soil-structure interaction (WSSI). The Reynolds-Averaged Navier-Stokes (RANS) equations are applied to describe wave motion in a fluid domain, while the seabed domain is described by quasi-state Biot equation. The interface of water and air is tracked by conservative Level Set method (LSM). The Finite Element Method (FEM) and backward differentiation formula (BDF) are respectively selected for space discretization and time discretization in this integrated FEM model. In the present model, only one-way coupling has been considered to integrate fluid model and seabed model. Several available laboratory experiments are adopted to validate present model. The objective of this paper is to present an integrated FEM model for the prediction on stability of pipeline subjected to water waves loading and to discuss the dynamic seabed response for several specific pipeline layouts. The result of validation demonstrates that numerical results have a good agreement with experimental results and this integrated FEM model can be further extended to practical engineering application. Some cases on the dynamic seabed response under the pipeline mounted on a flat seabed or inside a trench are investigated for pipeline stability. The conclusion drawn from this study is that the present WSSI model can accurately capture the mechanism of wave-induced transient seabed liquefaction around a half or fully buried pipeline.