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Offshore (geotechnical) engineering

David White

Centre for Offshore Foundation Systems

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Offshore (geotechnical) engineering

Offshore pipelines

Research techniques/tools

Research questions

Geomaterials science within COFS

Wider offshore (geotechnical) engineering at COFS

Potential links across faculty

Research tools

Common research ground

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Australias offshore pipelines

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Pipeline research techniques

Experimental

In situNumerical

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Pipeline research questions

Sleeper Pipeline

Alignment

in operation

Remnant berm

from hydrotest

As-laid

alignment

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Pipeline research questions

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A new geotechnical design context

Conventional engineering

stable structures on

an intact seabed

Modern pipeline design

mobility and transformation

structure and seabed

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Geomaterials science

0

0.2

0.4

0.6

0.8

1

1.2

0 10 20 30 40

Currentresistance/originalresis

tance

Cycle number

0

0.2

0.4

0.6

0.8

11.2

1.4

0.0001 0.001 0.01 0.1 1

Residualstressratio,res/'n

o

Velocity (mm/s)

Numbers indicate cycle number

1

1

11

20

5

5

With consolidation

intervals between cycles

Without consolidationintervals between cycles

Soil P (SILT)

HardeningReconsolidation

Solid fluidtransformation

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Example future WA developments

Cardoso & Oliviera 2010

Image courtesy of Woodside Energy Ltd

Image: Inpex / DMP annual

review

Image: Shell

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Related COFS research

Cardoso & Oliviera 2010

Image courtesy of Woodside Energy Ltd

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Future plan: ARC Centre forGeotechnical Science and Engineering (-2017)

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Wider links? Research tools

Numerical modelling Large deformation FE

Material point methods

Physical modelling

Centrifuges

O-tubes

Sensing, control and

acquisition

Image analysis

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Wider links? Common ground

CGSE Cross-pollination,

offshore onshore

civil engineering

Geomaterials

Potential links

offshore mining

Future energy

Renewables

wind, wave

Liquefaction?

JU punchthrough: 19 fatalities ever (reported)Cargo liquefaction: 66 in 18 months (reported)