Pipeline-Soil Interactions and Trenching
22 September 2010 North of England Branch Evening Meeting
Chairman Jerry Baker, Head of Discipline Pipeline & Subsea Integrity, Atkins Boreas
Sponsored by Geomarine
Presentations
Andy Hill, Senior Geotechnical Engineer, BP
For unburied pipelines in deep water, correctly predicting axial
“walking” and controlling lateral buckling is extremely sensitive to
the selection of the pipe-soil interaction parameters. Very soft
clay soils typically found in deep water are difficult to sample and
characterise especially within the first half metre of the seabed
where most pipelines interact with the soil. This presentation
provided a background to the geotechnical challenges associated with
adequately determining in-situ conditions and the use of soils
laboratory testing and physical modelling to determine pipe-soil
interaction behaviour. The presentation summarised the industry’s
ongoing efforts to provide design guidance on this important topic
for practising engineers.
Peter Allan, Director, Geomarine
Subsea trenching machines are widely used for the burial of pipeline. The equipment used includes jetting tools, ploughs and mechanical excavation systems. Much of the technology was pioneered in North East England, and this area remains the global leader. This talk reviewed the development of these systems and the different geotechnical conditions in which they were designed to work - from the North Sea, the Gulf of Mexico and beyond to the North West Shelf of Australia. The talk also described some experience with different trenching tools and how they may be used to meeting some of the engineering challenges.