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Department of Civil
and Environmental
Engineering
Spring 2017
Measuring Ice Loads
on Dams with Varying
Water Level
Supervisor:
Leif Lia
Co-supervisor:
Bård Arntsen
In cooperation with:
NORUT
Measurement stations
mounted at Dam
Taraldsvikfossen.
Photo taken during snow fall
on 17 Jan 2016
Aslak Bøhle Foss
MASTER THESIS
Background
Ice layers that lays on top of a reservoir or
water will establish a crystalline structure that
corresponds to the structure of a metal. Ice will
behave like a crystalline material with thermal
expansion, plastic deformation and cracking.
Ice layers on reservoirs could therefore apply
large forces on watercourse structures because
of thermal expansion or water level variations.
Most models are designed for static ice load,
while models including dynamic ice load or ice
load with water level variations are rare. Ice
loads largely influence the stability and static
properties of low concrete dams and the upper
7-8 m of concrete dams. In many cases the ice
load is themost critical loadandhasan impact on
mandatory rehabilitations of dams. It is therefore
important that the ice load is correctly projected
in the form of maximum load and behavior.
Measurements
New measuring equipment and new measure-
ment methods have made it both easier to
perform measurements and easier to achieve
more valid results. NORUT in Narvik has
been one of the leading firms in the Nordic
countries on this kind of measurement. NORUT
has an ongoing measurement program. The
measurements are performed on a water supply
reservoir in Taraldsvika just upstream of Narvik,
and measuring equipment is installed for the
winter 2016/2017. The reservoir in Taraldsvika
is small and can therefore be adjusted to
create water level variations, which will provide
particularly interesting measurements.