Engineers Australia

Geotechnics offshore Australia – beyond traditional soil mechanics

D.J. White, N.P. Boylan and N.H. Levy

Abstract

This paper provides an overview of current research into, and practice of, offshore geotechnics in Australia. Offshore geotechnics is a specialism within geotechnical engineering, and offshore geotechnics in Australia involves a further level of specialism, associated with the carbonate soil conditions found across our oil and gas development regions.

The geotechnical challenges faced by Australia’s offshore developments are continually evolving as exploration moves from shallow to deep water and the types of offshore facilities evolve. Previous projects in shallow water have led to the development of new piled foundation design methods and construction technologies, and have generated new solutions suited to local soil conditions, such as shallow cemented layers. Current research is now mainly focused on deep water sediments, anchoring and shallow foundations (rather than piled foundations), long pipeline networks and the geohazards faced beyond the continental shelf. Examples of research and novel design practice show that much of this technology lies beyond traditional ‘text book soil mechanics’. Defining characteristics of the deepwater frontiers include large deformations and transforming soil properties.

These challenges open up refreshing new avenues of research, and provide exciting challenges to the designer. Driven by these local needs, Australia is recognised globally as a leader in offshore geotechnics, and many of the technologies presented in this paper have become Australian exports into global practice.