Synergies between Very Large Floating Structure and Sea-Ice

to be presented at ISOPE-2008 July Conference in Vancouver

CUPERTINO, CALIFORNIA, USA, February 23, 2008 — ISOPE announces a plenary presentation on July 9 on his pioneering interdisciplinary research in the fields of ocean waves and ice science: Synergies between VLFS Hydroelasticity and Sea-Ice Research at the 18^th International Offshore (Ocean) and Polar Engineering Conference– ISOPE-2008 – at Sheraton Vancouver Wall Center Hotel, July 6-11, 2008. It will be presented by Prof. Vernon. A. Squire, University of Otago, New Zealand.

Immense theoretical progress made in the last decade or so has considerably advanced our understanding of how floating compliant sheets and plates are affected by ocean wave activity.  In part this has been inspired by the current debate on global climate change, which has recognized that ocean wave trains are destined to become more severe more frequently and will therefore carry a far greater destructive payload as they engage with less compact fields of pack ice that have already been weakened by elevated temperatures or with anthropogenically fabricated structures on the world’s continental shelves.

An early review by the presenter (Squire et al., 1995) was recently updated to take account of this extraordinary surge of activity on topics centred in the general area of ocean wave / sea-ice interactions, especially in relation to modelling (see Squire, 2007, and papers cited therein).  Models are now a good deal more sophisticated, with the most recent ones not requiring the ice to be uniform.

Yet a strong synergy exists between the Arctic and Antarctic marine geophysics being reported and a complementary corpus of publications in the offshore engineering literature that relate to hydroelasticity.  Many of the geocentric analyses described by Squire (2007) are equally applicable to mat-like VLFSs such as floating airports, e.g. Megafloat and other littoral projects proposed for Japan, mobile offshore bases, offshore port facilities, offshore storage and waste disposal provisions, energy islands including some wave power configurations, super tankers in a seaway, and floating breakwaters and bridges.

Unaccountably, there is a needless and deleterious disengagement of the two bodies of research that benefits neither the engineers nor polar science.  To boot, it is particularly irksome because, as Professor Squire recounts, there was a plan to build a ‘VLFS’ from ice even as early as World War II.  The British proposed in Project Habbakuk to construct a 2000 × 300 × 200 ft aircraft carrier with 40 ft thick walls and a displacement of 2 million tons or more from 280,000 blocks of ice, which was to be used against German U-boats in the mid-Atlantic.  The building material was subsequently changed to a mixture of ice and approximately 14% sawdust known as pykrete that was studied by the Nobel Laureate Max Ferdinand Perutz in later years.  A 1:50 scale model was constructed in Patricia Lake, Alberta, which engineers managed to keep frozen during the entire summer of 1943.  Because of its enormous cost, Project Habbakuk was eventually scrapped.  To quote Professor Squire ‘It is ironic, given the historical concert of glaciology and engineering that underpinned this ludicrous scheme, that I now find myself presenting a paper about floating bodies that aspires to reconcile two constituents of hydroelastic thinking that have disaffiliated.’

In a nutshell, Professor Squire’s ambitious goal in his presentation is to reconnect a currently very lively polar geophysical hydroelastic research strand with its partner in offshore and ocean engineering to help to avert, or at least reduce, our capacity to ‘reinvent the wheel’.

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ISOPE‑2007 and associated programs are available on www.isope.org.   Also see contact address: meetings@isope.org: Phone 1-650-254-1871.

By Jin S. Chung, ISOPE