0

Full Content is available to subscribers

Subscribe/Learn More  >

Design of Direct On-Seabed Sliding Foundations

[+] Author Affiliations
Andrew Deeks, Hongjie Zhou, Henry Krisdani, Fraser Bransby, Phil Watson

Advanced Geomechanics, Perth, WA, Australia

Paper No. OMAE2014-24393, pp. V003T10A024; 13 pages
doi:10.1115/OMAE2014-24393
From:
  • ASME 2014 33rd International Conference on Ocean, Offshore and Arctic Engineering
  • Volume 3: Offshore Geotechnics
  • San Francisco, California, USA, June 8–13, 2014
  • Conference Sponsors: Ocean, Offshore and Arctic Engineering Division
  • ISBN: 978-0-7918-4541-1
  • Copyright © 2014 by ASME

abstract

This paper describes a new framework for the geotechnical design of pipeline-related foundations (e.g. foundations for PLETs and Tees) designed to slide directly over the seabed during pipeline operation. This approach can present considerable savings in terms of fabrication and construction costs because of reduced foundation sizes.

Over the design life, a pipeline is likely to endure many thermal/ pressure load cycles due to product and flow rate variations during operation. These cycles result in the foundation sliding back and forth across the seabed within a footprint. These loads and corresponding motions impose cyclic shear stresses on the soil that can (i) degrade foundation bearing capacity and (ii) cause additional foundation settlement.

Often the key design consideration is whether or not the cumulative settlements will eventually compromise the integrity of the pipeline system to which the PLET and its associated foundation are attached. In addition to consolidation and creep, two key mechanisms are shown to control cyclic foundation settlement: (i) bearing mechanism induced burial and (ii) cyclic shear stress driven soil volume reduction. Their relative significance depends on the soil conditions (soil state) and input pipeline movements.

The paper presents key aspects required for the design of direct on-seabed sliding foundations, including the soil parameters and associated testing required. Validation of the design approach is illustrated by comparison to laboratory model tests performed on carbonate soils.

The impact of soil properties on potential foundation performance is illustrated with a design example and the importance of conducting site specific soil testing and settlement analyses is emphasised.

It is also illustrated that close integration of the pipeline, structural and geotechnical analysis is necessary to reliably quantify system performance of these novel foundations.

Copyright © 2014 by ASME
Topics: Design , Seabed

Figures

Tables

Interactive Graphics

Video

Country-Specific Mortality and Growth Failure in Infancy and Yound Children and Association With Material Stature

Use interactive graphics and maps to view and sort country-specific infant and early dhildhood mortality and growth failure data and their association with maternal

NOTE:
Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In