a new technology for precast units - Ratec.org

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Ratec GmbH, 68766 Hockenheim, Germany
Nevertheless, the possibilities opened up
by the new material are not yet adequately
exploited. This remains true, even when
argu ments such as:
• the low-noise processing, since
the vibrating equipment is no longer
required,
• the excellent surface quality of the
resulting products,
• the "sharp edges" of the concrete
parts and the
• economy in respect of the investment
in shuttering
all speak in favour of the use of SCC in concrete
precast factories, and justify its application.
In 2003 Reymann Technik wanted to
exploit SCC more effectively and efficiently,
and was planning a vertical circulation line
(for battery fabrication); for the first time the
company had to face a problem involved in
filling formwork with SCC. In the approach
being taken at the time, filling the vertical
shuttering (wall elements), which were 2.80
m high and 140 mm thick, and which had
a narrowing in the section at the top and
bottom, became a bottleneck for the plant,
because the concrete had to fully deaerate
while held in the shuttering, and also
because outstanding surface quality had to
be achieved.
PRECAST CONCRETE ELEMENTS
Upcrete ® and SCC – a new technology for precast
units with stringent requirements
Self compacting concrete (SCC) is currently emerging from obscurity to become a very popular construction material. Until now, its use has
been restricted to special tasks for which conventional concretes are not suitable. However, the financial benefits of SCC for standard products
were recognized at an early stage in the Benelux countries, and implemented in precast parts factories. Since then, SCC is growing in
popularity at more and more factories.
Pressure-proof
shuttering
Fig. 1: Elements of the process
Distributor system
Fig. 2: Concreting procedure
Pressure-resistant
covers
Overrun protection
Filling connection
Developing a new process for the
industrial production of precast concrete
elements
Two years later, Reymann Technik was contracted
to develop a modular house system,
using monolithic room modules. Once again,
the requirements were for outstanding surface
quality, thin-walled cross-sections, minimization
of the material used, and working
without turning or tilting the three-dimensional
module during the production process.
In a prototype phase, in which a section of
the complete element that would be shuttered
was tested, various filling options were
tried for the manufacture of a floor and two
walls as a monolithic unit cast in-situ.
As a result, it was found that the best option
was the use of a further developed SCC formulation,
in combination with pumping the
shuttering in a mounting stream from bottom
to top. This permitted very short filling times,
vibration was not necessary, a distribution
aid was no longer required and it was pos-
CPI – Concrete Plant International – 1 | 2009 www.cpi-worldwide.com

sible, using a suitable special concrete, to manufacture horizontally
covered surfaces of good quality.
Analogously to injection moulding, the concreting process involves
filling the horizontally shuttered areas by pushing out the air, along
with, as explained above, filling with a mounting stream from bottom
to top. The German expression "Druckguss-Steigspülungs-
Betonier-Verfahren" (DSBV - "concreting under pressure from bottom
to top in a mounting stream") has been replaced with the more pithy
engineering name of Upcrete ® .
Definition of Upcrete ® :
"upward concreting refers to the process of concreting highly complex
precast unit geometries using a method of concreting under
pressure from bottom to top in a mounting stream, which combines
the production of fair-faced concrete surfaces on every side, in-situ
fabrication, and the maximum possible economic efficiency"
Figure 1 illustrates the elements of the method, Figure 2 shows a
room module, including openings for the window and door, manufactured
by concreting using 6 m³ of concrete and a pumping time
of 25 minutes.
The advantages of the Upcrete ® technology
The pressurized filling is achieved with concreting pressure that is
greater than atmospheric. The use of pre-deaerated, self compacting
concretes simplifies the process, through which the most
awkward geometries can be entirely filled. The shuttering is filled
PRECAST CONCRETE ELEMENTS
Jörg Reymann studied industrial engineering, and since 1998 has been
a Managing Director at Reymann Technik/ Ratec GmbH
info@reymann-technik.de
with a mounting stream from bottom to top, which again permits the
in-situ manufacture of complex concrete bodies. The surfaces generated
are smooth formed finish on every side or, may be structured
through the use of formliners (tongued and grooved joints are now
also possible). Troweling up or smoothing of surfaces are therefore not
necessary. Only very small quantities of waste concrete are created.
The technique permits the component to have very high dimensional
precision, and offers very high performance (max. 300 l/minute).
This means therefore that the manufacture of the concrete parts is
quiet, does not waste material, is efficient and comfortable.
The elements of the method have been further developed on the
basis of the discoveries made during module manufacture, and
transfer of the technique to vertical manufacture is under development.
The Upcrete ® Peristaltic Pump (UPP), also known as the hose or
rotor pump, is an important part of this new production method. The
pump allows small quantities of concrete to be pumped, and is ideal -
ly adapted to the needs of the Upcrete ® technology and the conditions
of a precast plant. The pump, together with its integrated
cleaning system, measures about 3000 mm in length, 1500 mm in
Brain. Solutions.
ICCX Oceania 2009
Sydney, Australia
March 30 – April 2
Stand No. 67
RATEC is No.1 in the development of magnetic forms and accessories. Our products enjoy success around the world,
lowering formwork costs and improving production quality. With the new Upcrete ® Technology
we set Standards in production of effi cient and high quality concrete elements. Ask the specialist for detailed information.
RATEC GMBH
Karlsruher Straße 32, D-68766 Hockenheim
Phone +49-6205-9407-29, Fax +49-6205-9407-30
info@ratec.org, www.ratec.org

166
Fig. 3: Upcrete ® Peristaltic Pump (UPP)
width and is 1700 mm high. It weighs 2.3
tonnes, and can be transported by a crane
and forklift truck; it can be controlled by a
single worker using a bidirectional radio
remote control unit. The pump can handle a
maximum grain size of 16 mm, and its pumping
rate is continuously controllable, allowing
a filling rate of 18 m³ concrete per
hour. The pump is, of course, fitted with a
sensor for burst hoses and with a level sen-
Fig. 4: The pump in use in a precast unit plant
sor in the anticipator buffering. The filling
level sensor provides an interface with an
automatic connection to the anticipator buffering,
the bucket transport system and the
mixing equipment. The integrated cleaning
unit, which has its own water reservoir,
allows the pump to be cleaned, as well as
the supply hose as far as the connection
with the shuttering. After making the universal
UCI pump connection at the connection
PRECAST CONCRETE ELEMENTS
to the shuttering it is only this pump connection
that has to be cleaned manually.
When using the pump in the plant, it is
necessary to ensure that all of the transport
of the SCC to the pump, whether or not an
intermediate buffering is used, is done with
as little air as possible.
Production of individual components
possible, including sandwich walls
The Upcrete ® method also creates an
opportunity for new thinking about vertical
fabrication. By filling from below, not only
can solid walls and ceilings be manufactured,
but also, for the first time, double walls,
which is something of a revolution. In a pilot
project, Ratec created a battery shuttering
scheme, capable of extension, allowing the
manufacture of precast parts with thicknesses
of between 60 and 450 mm (sandwich)
in one shuttering. The scheme consists
of pair of linear movable outer formwork
panels and of inner panels that are moved
in and out, alternating with the outer panel
pair; it is similar to the circulation technique.
The outer panel pair can be reused after
holding the concrete for between 4 and 5
hours. The concrete element, which cannot
yet be lifted, can remain out of the outer
panel pair for the rest of the hardening
time. The inner and outer panels have controlled
heating. By filling from the bottom
up, the original theory behind battery fabrication
has been almost turned on its head,
as a result of which the lower floor no longer
has to be adjusted, and the upper wall
height is generated by a magnetically stop
switch. The grant of a patent illustrates the
uniqueness of this system.
Intelligent work preparation means that this
vertical fabrication can not only be carried
out with great efficiency and whilst using a
very minimum of space, but that products
that are either difficult or impossible to
manufacture using the horizontal method
can be made. By incorporating all the
important, familiar, technical components
of a circulation plant (transverse movement,
friction drives, roller conveyors, control technology)
it has been possible to implement
these advantages in an expanding scheme.
Monitoring during the filling is enabled
through the overflow valve, overflow protection
and through the radio remote control.
Other applications: The new process technology
is also suited to the manufacture of
other products as well as for integration into
existing shuttering equipment, although the
capacity of such equipment to withstand
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PRECAST CONCRETE ELEMENTS
Fig. 5: Layout of a battery fabrication plant suitable for Upcrete technology
Fig. 6: Battery formwork for Upcrete technology
YOUR SUCCESS IS
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TOTAL SOLUTIONS
FOR THE
PRECAST INDUSTRY
For your precast concrete factory we
deliver turnkey complete systems as well
as single components. Give us a call!
Concrete Solutions
53. BetonTage
10.–12. 02. 2009, Neu-Ulm
www.betontage.com
Fig. 7: Sandwich wall and solid wall – both made with
Upcrete technology EBAWE Anlagentechnik GmbH · Dübener Landstraße 58
04838 Eilenburg · Germany
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Tel.: +49 (0)3423-665-0 · Fax: +49 (0)3423-665-200
info@ebawe.de · www.ebawe.de

168
Fig. 8: View of the outer panel pair for the Upcrete battery shuttering
Fig. 9: Curved wall, with differently coloured concretes, made using the Upcrete technology
PRECAST CONCRETE ELEMENTS
pressure would have to be checked.
Tubbing formwork, garbage can boxes,
staircases and sound insulation walls have
already all been filled with this technology.
As a particular example, a curved wall with
a footing was filled from the front with 6 m³
of concrete. A cover was added to the existing
formwork, and different concrete formulations
were used, both in order to check
different surface qualities and also so that
the flows occurring within the shuttering
could be seen through the difference in
concrete colour. This allowed the filling time
to be halved.
The advantages of this method have already
been demonstrated on a variety of products
and under different external conditions, al -
though by no means every possibility has
yet been examined. The following advantages
in particular have become clear from
applications so far:
• fast concreting times
• ideal surface quality with a minimum
of air void content
• optimum dimensional accuracy
• smooth formed finish or profiled on
every side
• extremely awkward geometries can be
manufactured in-situ
• new products and a height potential
for rationalization of existing products
through easy retrofitting
• growing production plant can easily
be adapted to market capacity
This new technology, which will in no way
replace or displace horizontal fabrication,
nevertheless creates possibilities that permit
further competitive advantages in the precast
parts industry.
FURTHER INFORMATION
RATEC GmbH
Karlsruher Strasse 32
68766 Hockenheim, Germany
T +49 6205 940729
F +49 6205 940730
info@ratec.org
www.ratec.org
Contact for the USA
RATEC LLC
13000 Automobile Blvd, Suite 501
Clearwater · FL 33762, USA
T +1 727 3637732
F +1 727 363 7463
infoUS@ratec.org
www.ratec.org
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