North American Special - Trenchless International

SPR technology
SPR utilises steel-reinforced interlocking PVC profile strips sealed
in place by a high-pressure grout. The installation equipment can be
utilised via standard manhole access points without site excavation.
Sekisui’s CPT SPR technology can also be installed in vertical
applications such as wet wells, access shafts and other large diameter
structures.
SPR is a spiral winding technique which is particularly well suited
to the renewal of very large diameter pipelines – up to 5 metres. In
addition to standard circular profiles, egg-shaped and horseshoe
profiles, any custom shapes can also be provided. The winding
machine is specially adapted to each project, enabling it to cover
a very wide range of applications. SPR technology is already being
successfully deployed in Asia and the USA to renew large diameter
pipelines.
The SPR process is unique as it can provide a customised structural
solution to aging pipelines. It can be engineered to correct hydraulic
anomalies as well as restore the slope of the original pipe. The
interlocking edges of the profile create an impermeable mechanical
lock that can withstand strong deformational forces.
SPR liners have been tested in accordance with industry standards
and meet or exceed the standards for spiral wound PVC Profile Wall
Liners ASTM F – 1697-02 and F 1741-02a. Furthermore the SPR PVC
profile has a Manning’s coefficient of n = .010.
PROJECTS
April 2009 - Trenchless International
All wound up in Poland
Szczecin, Poland is the first city in Europe to benefit from a new Japanese renewal technology, spiral
pipe renewal (SPR).
When the tender for a renewal project
in Szczecin, Poland was first issued at the
beginning of 2008, GRP short-pipe lining
was specified. However, after some extensive
research by the customer it was found
that it would be very difficult to maintain the
required water flow rates using the chosen
technique. Severe deformation of the old
pipe, which was not identified during the
planning stage, meant that if a GRP shortpipe
lining was used, the diameter of the
renewed pipe would be much smaller,
and so reduce the capacity of the new
pipeline.
Another challenge was posed by the fact
that the pipeline being renewed in Szczecin
was a main collector in the city centre,
where it would be impossible to construct a
dewatering system. Even though a large pit
for the GRP lining had already been dug,
at the last minute the customer decided
– based on the new demands faced – to
opt for the first ever European use of SPR
technology.
The masonry-lined combination sewer
was built over a century ago. The condition
of the sewer had deteriorated severely
in recent years. As a result of continuous
traffic and other external loads, longitudinal
cracks had formed along the crown of the
pipe, leading to increased deformation.
Renewal had become a matter of urgency.
There were also a large number of deposits
and other obstacles protruding as much as
50 cm into the pipe. Consequently, it was
clear that thorough cleaning and jet-grouting
work would have to be carried out prior
to the renewal process. The SPR installation
process can be divided into three key
stages: the winding of the PVC profile, the
construction of the bracing system and the
grouting of the annulus
Winding process
The winding was executed starting from
the manhole access shaft downstream to
the next shaft. Based on the local conditions
and the existing 18 metre long pit, the
stretch of pipeline scheduled for renewal
was divided into four segments. The winding
machine installed the profile in the existing
pipeline guided the profile and formed it
into the desired shape, with an inner
diameter of 2,240 x 1,600 mm.
The winding machine
moved one
The SPR winding machine pulls the SPR profile into place and
engages the dual locking mechanism.
profile width forward on each rotation of the
profile, locking the profile edges to form a
water-tight pipe in the process.
As soon as the machine’s forward
momentum had taken it to the next shaft,
the winding process was stopped and
the profile separated. The team from the
Polish construction company, together with
the Japanese engineers, laid the
winding machine and
the profile reel to the
next shaft, which
then served as the
new starting
Bracing the shaft.
point for the next installation phase and as
the conduit through which the profile was
again guided by the winding machine, as
in the first phase.
Bracing system
In the next step, when the winding process
was complete, the expert team constructed
the bracing system. The braces were introduced
through the shaft into the spiral
wound pipe and carefully installed. The
constructed cross-section of the bracing
system prevents lifting of the new spiral
wound pipe during subsequent grouting
and prevents deformation.
Grouting
The grouting process for each renewal
segment comprised injection of the grout
into the annulus between the old pipe and
the spiral wound PVC profile and curing of
the grout. The team executed the grouting
work in three stages. Then the braces
were dismantled and installed in the next
renewal segment. The pit area was grouted
to a statically determined height above the
spiral wound PVC profile.
SPR technology in Poland.
Below: SPR PVC profile is unreeled and fed
into the winding machine.
For further information contact Christopher Moritz at KMG LinerTec GmbH:
christopher.moritz@sekisuicpt.com
Summary
All work was carried out by the team
comprising workers from the local Polish
agent of Sekisui CPT and Japanese technical
specialists. The renewed sewer
is beneath one of the main streets in
Szczecin, and collects the rainwater and
sewage from all the smaller surrounding
systems. Work was interrupted several
times due to flooding and above average
rainfall, and lost time had to be made up
for at night. However, since SPR can also
be applied with drainage, the installation
could be resumed without problem following
the enforced breaks.
Headed by Christopher Moritz, an
expert team provides technical know-how
and support covering all aspects of the
new technology. “One of the key benefits
of the SPR PVC profile from Sekisui is its
environmental sustainability – including 60
per cent less fossil fuel consumption, 30
per cent less energy use and four times
lower CO2 emissions in production.
“That is one of the factors that will
enable us to achieve our goal of delivering
premium renewal solutions and becoming
the market leader in the renewal of
large-diameter pipelines in Europe,” said
Mr Moritz.
Despite the very difficult weather conditions,
the European premiere of SPR
technology was successfully completed
within approximately two months.
PROJECTS
April 2009 - Trenchless International
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