AGM & Offshore geotechnics

Prof David White

This lecture will describe novel geotechnical technology that is supporting the frontiers of offshore oil and gas development, with a focus on the boundaries of traditional soil mechanics.

Offshore developments involve a variety of infrastructure placed on the seabed or anchored to it, including extensive networks of on-bottom pipelines. A particular challenge is often the mobility of the infrastructure and the seabed during installation and operation. For example, anchors are dragged to their operational position, pipelines sweep laterally and axially over the seabed during operation and catenary risers dig deep trenches where they touch down on the seabed. The consequent disturbance and healing of the seabed soil leads to changes in topography and strength.

Novel technologies to characterise the seabed through such episodes of disturbance are described, as well as physical modelling that simulates the in- service behaviour of pipelines and seabed infrastructure. A recurrent theme through these design challenges is the beneficial effect of soil failure, and the requirement to predict the load-displacement response through gross deformations that invoke changes in the strength and stiffness of the soil.

These new regimes of geotechnical behaviour open up refreshing new avenues of research, and provide exciting challenges to the designer.

About the speaker

Prof David White Professor, Centre for Offshore Foundation Systems, University of Western Australia

Research and practice beyond the boundaries of traditional soil mechanics

David White is a Professor at the Centre for Offshore Foundation Systems at the University of Western Australia. His research encompasses many aspects of offshore geotechnics and soil behaviour, from the initial characterisation of the seabed using novel laboratory and in situ test techniques, to analysis tools to quantify the response of foundations and pipelines for design. His research blends physical modelling, using the UWA centrifuge facilities, with numerical analysis and field observations. He has a particular interest in large deformation problems involving changing geometry and soil properties, such as pile penetration, pipeline buckling and submarine slide run out. He is also active in industry practice, as a Principal Consultant for the Perth-based company Advanced Geomechanics.

Professor White has authored 7 invited conference keynotes and book chapters on piled foundations and pipeline geotechnics. His >150 career publications have won 5 prizes. He was awarded the 2010 Anton Hales Medal by the Australian Academy of Science and the 2011 Western Australia Tall Poppy Science Award. He was the 2011 Western Australian Early Career Scientist of the Year and his research projects have attracted 4 industry awards including the WA Engineers Australia 2012 award for research and innovation.

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