Effects of Consolidation under a Penetrating Footing in Carbonate Silty Clay
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 141, Issue 9
Abstract
The effects of consolidation under a footing are generally viewed as beneficial due to the resulting increased capacity. Consolidation may also be actively sought because it minimizes footing embedment, which can be critical for the installation of mobile offshore jack-ups because available leg length is limited. However, it can also set the platform footing up to subsequently punch through the strengthened zone, with potentially serious consequences. The problem is complex due to the three-dimensional nature of consolidation. Further, footing penetration leaves the soil above heavily remolded and generates large excess pore pressures below, such that the soil state even prior to consolidation is significantly altered from its in situ conditions. This study has taken an experimental approach to investigate the effects of consolidation around a footing penetrating into carbonate silty clay and, following detailed discussion of the response, offers a framework to predict the changes to the load-penetration curve.
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Acknowledgments
The first author is the recipient of an Australian Research Council (ARC) Postdoctoral Fellowship (DP110101603) and the third author is the recipient of an ARC Laureate Fellowship (FL130100059). This work forms part of the activities of the Centre for Offshore Foundation Systems (COFS), currently supported as a node of the ARC Centre of Excellence for Geotechnical Science and Engineering and as a Centre of Excellence by the Lloyd’s Register Foundation. Lloyd’s Register Foundation invests in science, engineering, and technology for public benefit, worldwide. This support is gratefully acknowledged.
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© 2015 American Society of Civil Engineers.
History
Received: May 27, 2014
Accepted: Mar 24, 2015
Published online: May 12, 2015
Published in print: Sep 1, 2015
Discussion open until: Oct 12, 2015
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