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Department of Civil
and Environmental
Engineering
Spring 2017
Anchoring of Bend on
Penstock with PU Foam
Supervisor:
Leif Lia
Co-supervisor:
Tor Oxhovd Svalesen
In cooperation with:
Statkraft AS
Buried penstock connecting Lille Måsevann to Store Måsevann
Stian Løbø Aaker
MASTER THESIS
Background
The drop in Norwegian electricity prices
in recent years has reduced the potential
income for new small hydro projects, and
therefore measures to reduce the costs must
be introduced. Today the most commonly used
backfill for penstocks for small hydro are gravel
and rockfill, which is time consuming and costly
due to transportation. Penstock BV with Guy
Harris developed a method with polyurethane
foam as a replacement for gravel and rockfill
which may lead to lower investment costs and
reduced construction time. Statkraft AS initiated
a research project to verify this method.
The project involves the construction of Lille
Måsevann Pump with a buried penstock
connecting Lille Måsevann to Store Måsevann
– the intake reservoir for Adamselv hydropower
plant. Lille Måsevann Pump is the first of its kind
where sections of the penstock, including two
bends, are enveloped in polyurethane foam (PU
foam).
The main objective of this master thesis is to
further develop the use of PU foam for the
anchoring of bends. Two laboratory tests will
be carried out to investigate the structural
properties of foam in bends and adhesion
between foam and pipe.