Coupled Finite Element Analysis of Partially Embedded Offshore Pipelines during Vertical Penetration

Abstract:

Diverse vertical embedment response is observed for partially embedded pipelines when experimentally tested under similar initial and boundary conditions. Although vertical resistance of pipelines is presented through simple analytical solutions, a number of factors contribute to complications in implementing these theories into practice. The objectives of this research is to provide a more detailed investigation on the vertical embedment for the partially-embedded pipelines (PEPs) using a coupled large deformation finite element (CLDFE) analysis with contact. A modified Cam Clay (MCC) model represents the elastoplastic response of the soil. The model of pipeline embedment investigates the effect of drainage condition on heave forming with respect to rate of penetration. Besides, effect of frictional contact on the heave development and wedging effect is investigated and design-related considerations are proposed. It is shown that depending on the rate of pipeline penetration and soil consolidation rate, the pipeline penetration response can be categorised as undrained, partially drained or fully drained.

• Periodical: Applied Mechanics and Materials (Volume 553)
• Pages: 428-433
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.553.428
• Online since: May 2014
• Authors: Yousef Ansari*, George P. Kouretzis, Dai Chao Sheng
• Keywords: Coupled Analysis, Large Deformation Finite Element, Modified Cam Clay, Partially Embedded Pipelines, Soil Heave

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