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SAMC
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T • Annual report 2012
An example of this effect has been identified at the sheet-
pile wall of the Kapp Amsterdam quay at Spitsbergen.
Experts theorize that the deformation of the sheet-pile
wall has resulted from a combined effect of thermal
expansion and tide. The combination of brine drainage
and increasing brine volume at higher temperatures
has been deemed as key.
A team of UNIS researchers – Professor Aleksey
Marchenko and his students fromUNIS – havemeasured
the conditions over a period of several years and in 2012
SAMCoT researchers installed load cells inside the
sheet-pile wall to quantify the pressure from the ice.
Laboratory experiments with fibre-optic sensors have
been used to quantify the thermal expansion of sea ice
as a function of salinity and temperature.
Professor Marchenko gave an overview of the topic in
an invited lecture at the International Ice Symposium
(IAHR) in Dalian China in June 2012. Whereas two
conflicting models of the problem have been published,
Prof. Marchenko explains in his findings that it makes
sense to combine the two approaches.
How to model warming permafrost?
Frozen soil contains pure ice, soil particles, liquids with
dissolved salts and gasses. As permafrost deforms
(especially warming and melting permafrost), vital
thermal, hydrological and mechanical processes occur.
The different phases of deformation are in thermal
equilibrium and warming permafrost in particular is
sensitive to small changes in temperature. In order to
describe the deformations of permafrost mathemati
cally, SAMCoT researchers needed to study the coupled
Thermo-Hydro-Mechanical (THM) process.
Professor Thomas Benz and PhD candidate Yared
Bekele were active in 2012. Bekele conducted a state-
of-the-art report about THM modelling of frozen soils
and also started the creation of his own numerical
solution. His first step focuses on effective formulation
of governing and constitutive equations of frozen soil as
a porous medium.
Fig. 7: Aleksey Marchenko and Kåre Johansen install a load cell inside the sheet-pile wall to measure the ice load
during the winter of 2012-13.
Photo: Jomar Finseth