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Annual Report 2016
SAMCoT
FLOATING STRUCTURES IN ICE
Since the start of SAMCoT our researchers have worked towards acquiring the necessary
knowledge to develop the analytical and numerical models required by industry in the field
of Floating Structures in Ice. Our team focusses on the prediction of loads exerted by first-
year and multi-year level ice, ridges and icebergs as well as the performance of floating
structures in ice.
Changes in the boundary conditions and new opportunities encountered along the way have
determined the research path followed towards this aim. Our group is composed of seven
researchers, three postdocs and three PhD candidates.
engineering models of ice impact loads and numerical
simulations of ice crushing.
Within the context of local ice loads due to an abnormal
ice event, our group has continued to address two
effects: firstly the effect of structural deformations and
secondly the effect of surrounding water. The arbitrary
Lagrangian-Eulerian (ALE) and coupling algorithms have
been validated through comparison with model tests of
an ice-structure collision. The effect of viscosity and
the equation of state for the water model within the ALE
formulation are insignificant, whereas the choice of the
element size has a noticeable effect on the compu-
ted contact forces and the motions of the impacted
structure.
Variation of the mean value and the standard deviation
(as error bars) of the crushing specific energy (MSEI) as
a function of crushed volume.
ICE ACTIONS
From an engineering point of view, ice actions can be divided between
local and global ice actions on a structure.
8000
6000
4000
2000
0
0
0.05 0.1
0.15
0.2
0.25
0.3 0.35
0.4
Data from all 10 tests
Crushed volume V , (m )
z
3
LOCAL ICE ACTIONS
The year 2016 started with Martin Storheim successfully
defending his thesis “Structural response in ship-plat-
form and ship-ice collisions”on 19
th
January. He
presented a novel way to separate two different mesh
scale effects (termed geometric and material). He also
discussed the micromechanical process of fracture and
related it to macromechanical processes that can be
captured with coarse shell elements.
Another of our researchers working on local ice actions,
postdoc Ekaterina Kim, re-analysed the data from
the indentation experiments conducted on natural
iceberg ice at Pond Inlet in 1984. In collaboration with
Robert Gagnon (Research Council Officer for National
Research Council Canada, St John’s) they found that,
for three different spherically-terminated indenter
sizes, the crushing specific energy of the ice shows
little dependency on the volume of the displaced ice
and tends towards a constant value. In addition, their
results showed no apparent correlation between the
crushing specific energy of the ice and indenter size,
nor was there a clear consistency in the values for tests
conducted with the same indenter. This means that the
crushing specific energy is an important parameter in