The British Geotechnical Association (BGA) is the principal
association for geotechnical engineers in the United Kingdom.
The British Geotechnical Association (BGA) is the principal
association for geotechnical engineers in the United Kingdom.
Thursday 21st November 2019 at 18:30 hours
Institution of Civil Engineers, One Great George Street, Westminster, London SW1P 3AA
The Géotechnique lecture is a biennial lecture nominated by the Editorial Panel of the journal Géotechnique.
The Géotechnique lecture will be held Thursday 21st November 2019 at 18:30 hours. Registration and tea & coffee will be available from 18:00.
This event is free to attend, but advance booking is required, via the link at the bottom of this page.
The event will be webcast live - use this link to join the event on line.
Please join us afterwards for drinks sponsored by COWI.
Offshore infrastructure is an essential element of our energy system and our communication networks. This infrastructure rests on a seabed that evolves with time – due to environmental processes, and due to the action of the infrastructure itself. The design of cables, pipelines, foundations and anchoring systems is made complex by the evolution in soil properties caused by the whole-life loading history – from installation, through in-service loads, to the end-of-life solution. In addition, ocean-seabed-infrastructure interaction can cause sediment transport and scour, altering the seabed geometry and causing changes in embedment and support.
This Geotechnique Lecture tackles the geotechnical challenge of designing infrastructure for an evolving seabed, examining ‘whole-life’ changes in seabed strength and geometry.
Changes in soft soil strength arise from both monotonic dead loads and cyclic live loads. Examples for pipelines, foundations and anchors will be shown, drawn from centrifuge model tests, numerical simulations and field data. Significant changes in strength by a factor of 2-3 are typically evident. These effects matter most at shallow depths, close to the seafloor. New types of element test and penetrometer will be shown, which target this near-surface strength.
Meanwhile, in both coarse-grained and fine-grained soils, excitation from the ocean or the infrastructure can lead to sediment transport, scour and subsidence. These effects are often, but not always, detrimental to design. Examples of this fluid-structure-seabed interaction are described, from the laboratory and the field.
The lecture will close by showing how these whole-life effects can be harnessed through innovative technologies, such as
Modern numerical techniques, such as finite element limit analysis, now provide definitive solutions for the stability and bearing capacity of structures, if the geometry and strength of the surrounding soil are known. The examples in this lecture highlight the remaining uncertainties.
David White is a geotechnical engineer working on infrastructure, ranging from offshore energy facilities to onshore civil engineering projects. He is Professor of Infrastructure Geotechnics at the University of Southampton
His work has ranged from fundamental geotechnical studies into the mechanical response of soils to leadership of cross-disciplinary initiatives spanning the engineering of offshore facilities, and novel construction machinery to remote monitoring technologies for urban construction. His end goal is to devise reliable design methods for efficient and predictable infrastructure, and roll out new technologies to better characterise and control the behaviour of geomaterials. Some of his work has led to new design codes endorsed by industry verifiers and standards committees, while in other areas the outcome has been new gadgets to probe the properties of the seabed.
Before joining the University of Southampton David held the Shell Chair in Offshore Engineering at the University of Western Australia and was Director of the ARC Research Hub for Offshore Floating Facilities.
David has undergraduate and PhD degrees from the University of Cambridge and was a Research Fellow at St John’s College and a University Lecturer in Cambridge before departing for Australia in 2006. He is a Fellow of the Royal Academy of Engineering, the Australasian Academy of Technological Sciences and Engineering, the Institution of Engineers Australia and the Royal Institute of Naval Architects. He is the author or co-author of more than 250 publications, serves on various code-writing committees to translate research into practice, and partners with industry on consulting projects to bring research and practice closer together.
Please join us afterwards for drinks sponsored by COWI.
