Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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Method and arrangement for the manu~acture of pre-cast
plate-like concrete elements on the building site
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The invention lies in the field concerning the
manufacture of pre-cast concrete elements. It ha~ the
object of providing a method and an arrangement for
the manufacture of pre-cast plate-like concrete
elements - referred to in short as "elements" from now
on - on the building site. The invention has the
further object of providing a method whereby, with the
help of simple additional devices, such structures as,
e.g. hollow interior walls and two-sheet, highly-
insulating exterior walls can be manufactured.
~arge-area wall and ceiling elements of very smooth
concrete can play a sub~tantial role in the long-
overdue ratlonalisation and modernisation in housing
construction. In contrast to conventional ma~onry
these elements have the advantage of being able to
serve simultaneou~ly as heat transfer elements and
canals for ventilation, heating and installations. As
opposed to light-weight constructions, they have the
advantage of en~uring better sound-proofing, heat
retention and refractoriness, as well as greater
durability.
For interior walls, particularly dividing walls in
houses or flats, the elements are constructed as ribbed
walls. Two ribbed walls are 30 positioned in each case
that their rib~ interlock. The ribs can be chosen to be
so strong as to act as supporting component parts.
Continuous hollow space~ occur between the ribs~ which
can be made use of for heating and installation
~ purposes.
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~or the outer walls, the elements are constructed as
highly-insulating, two-sheet component parts, this
being done in several consecutive stages whereby an
element is produced consisting of a ribbed wall,
between whose ribs a very strong insulation layer of
hard-foam plates is embedded, projecting above the ribs.
~he front edges of the ribs are al~o insulated. ~inally
with the help of 510ts provided in the hard-foam plates,
a facing of cement mortar with pre-determined breaking
points is poured over. ~etween the hard-foam insulation
and the ribbed wall, hollow spaces are provided which
can be used as air-circulation canals and which separate
the facing and the ribbed wall acoustically from one
another in such a way that the elemen-t becomes a two- -
sheet wall. All these working stages are carried out
according to the invention on a special horizontal table.
After a short setting time the table and element are
raised, the element placed in a vertical po~ition, and
the table brought back to its horizontal po~ition so
that the next element can be concreted. ~he elements
stacked vertically do not require any further special
support~ ~hey are left standing until they have achieved
their full rigidity.
~he invention provides a method for the production of
pre-ca~t plate-like concrete elements by casting on a
casting table provided on its surface with a large-area
mold, particularly on the building ~ite J characterized
in that after a short setting time for the concrete,
the concrete elements together with the casting table
are raised by rolling away the table on curved runners
reaching to the front edges o~ the table, and in that
the concrete elements in the raised position are drawn
off from the large-area mold and are stored in the
position thus assl~med.
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One advantage of this method lies in that a small
specialized operating force with little expenditure on appara-
tus can manufacture all necessary elements for a building
project and that the excavation need only be started after com-
pletion and hardening of all elements, with the help of a mobile
crane the building can then be put up in a few days. In this
way, the costs for machinery being used are kept to a minimum.
The method, in a more specific embodiment, is charac-
terized in that the runners of the casting table are circularly
curved and that the centre of curvature lies at the centre of
gravity of the concrete element. When drawing off the concrete
element from the large-area mold, the casting table is pushed
back in relation to this by at least the breadth of the element
to be subsequently concreted. At the same time, a shed accord-
ing to the invention is pushed back by at least the breadth of
the following element. The mold inserts necessary for the pro-
duction of ribbed walls according to the invention are jointed
into a grillage which is hung from the ceiling of the shed and
by means of a winch is drawn off from the ribbed wall and either
raised to the ceiling or lowered respectively. m e cable being
driven by the winch according to the invention is led over
rollers in such a way that the raising and lowering respectively
of the casting table can also be effected by means of this winch.
An apparatus in accordance with the present invention
for casting plate-like concrete wall elements comprises a cast-
ing table, and a wide area mold affixed thereto. The casting
table is supported by a pair of curved runners, and the casting
table is stable when the wide area mold is in a horizontal
position and rockable upon the pair of curved runners to place
the wide area mold in substantially a vertical position.
Removal means are operable to separate the wide area mold from
the concrete wall element when the wall element is in a vertical
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position. The removal means can include a member forming the
lowest part of the wide area mold when the wide area mold is
in a vertical position.
A preferred embodiment of the apparatus in accordance
with the invention provides for the casting table standing on
sled-like understructures which enable it to be rolled away
and thus raised into a vertical position on the understructures.
The runners for the casting table according
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to the invention are circularly curved with the centre
o- curv~ture lying at the cen-tre of gravity of the
element to be concreted. The curvature of the runners
is so designed that the moments resulting during
lifting and lowering of the -table correspond as nearly
as possible to a desired pattern of moments. The lowest
part of the casting table mold according to the
invention consists of a support not being rigidly
connected -to the rest of the mold framework The
casting table according to the invention is provided
with winches, with whose help one can press against the
support and thus draw off the casting table.
The invention further provides for winches suitable
for use in connection with the above-mentioned casting
table, being characterized in that their lift is
sufficiently large as to allow the casting table to be
pushed further during the withdrawal process immediately
into the next concreting position.
In a special embodiment of the invention, the casting
table is provided with claws which prevent the concreted
element from sliding prematurely off the mold framework
during the erection process.
According to a preferable version of the invention, a
movable shed is provided, standing on rollers and being
moved together with the casting table. The movable shed
according to the invention is characterized by having a
rod against whose end the casting table pushes when
being moved on, so that the shed itself is moved on by
the same amount as the table. The movable shed according
to the invention is provided further with a winch and a
cable being led over rollers, by means of whicn cable
the casting table can be raised. In addition, the
ceiling of the movable shed according to the invention
has further rollers attached to it over which the cable
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can be pas3ed so that with the help of -the winch further
casting elements can be wound up and let down.
Further advantages and details of the invention are
described in the following :
A preferred version of the set-up is ~hown in the
diagram,
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~igs. 1 and 2 show two lateral views of the erectable
casting table according to the inventio~ in the
horizontal posit~on which it assume~ during concreting.
Fig. 3 shows a movable shed in which the casting table
is accommodated, and which is provided with additional
devices for making ribbed walls.
Fig. 4 shows a detail of the withdrawal device for -the
casting table shown in Figs. 1 and 2 .
~ ig. 5 shows an isometric representation of the movable
shed with partly raised casting table.
Corresponding part~ are provided with the same reference
symbols in the figures.
~he casting table 1 stands on two sled-shaped under-
structures 2, being connected by support 3 and a
structural girder 4 which is rigid in all directions.
~hese components are braced to a rigid supporting frame
by means of steel cables 5 which are provided with
stretching devices 6. ~he distance between understructures
2 is so chosen that support 3 bends minimally under
load.
The supports 7, which can for ex. be customary wooden
mold supports, are attached in cros~,direction on the
supports 3, and the large-area mold 8 is then attached
to the support 7. The support~ 7 and the mold 8 can be
of wood or steel as according to the size of the form
being produced. ~he supporting frame stands with the
,understructures 2 on strong lengths of squared timber
(crane beams, for ex.) 9, which are laid exactly
horizontal and at the same level on the ground. For
exact positioning a mortar bed i~ to be recommended.
It is also possible to use some other foundation of
,adequate rigidity, for 6X, concrete-reinforced slabs or
steel supports. ~he side facing the bent part of the
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understructure 2 becomes the underside, Support 7 and
mold 8 do not reach right to the bottom. ~he lowest
par~ of the mold is formed by a support 10 running the
whole leng-th o~ the casting table. ~his support 10 is
laid on the supporting frame. It is no-t rigidly connected
to the rest of the mold,
Fig. 4 shows a detail of the casting table in raised
position. On the underside of the understructures 2
there is in each case a tripod 11 attached. A bushing 12
provided with an internal thread i8 welded onto the tri-
pod. A strong threaded rod 13 having a turning device
14 is screwed through the bushing 12, The threaded rod
projects through a hole 17 in support 10 to reach into
a threadless bushing 15 similarly welded onto support
10. ~here is a fixture 16, which for ex, can consist of
two checked nuts, on the threaded rod 13. In addition
there is a claw 18 attached to the tripod.
The casting table 1 is accommodated in a movable shed 20.
~his can be of simple wooden beam construction or of
a steel pipe constructio~ with an asbesto~ cement or
some other covering, It stands on rubber-tyred rollers
21 which rest on the already-completed concrete
components, A supporting framework 23, to which the
already-completed walls are attached in vertical
position~ is attached to the crane beams 9, ~hese
frameworks have ~upports 24 on which the rollers 21
stand before the first walls have been completed,
On the other side the shed 20 stands on rollers 22
which run on the crane beams 9. ~he shed can be
attached by means of clamp~ or other devices to the crane
beams 9 and the framework 2~, or to the already completed
walls, so that it cannot be lifted by wind force~,
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The lateral bounding framework is attached to the
large-area mold 8. It can consist of a few rigid metal
girders which are screwed on and can therefore be
postitioned with high accuracy. In the region of the
understructures 2 the bounding framework con~ists of
short length~ of squared timber 19 which are inserted.
~he walls are so produced that they are first of all
concreted on the horizontally-positioned table 1 After
a short hardening time they are raised by rolling back
the table on the runners of the understructures 2. If
the curvature of the runners is chosen to be circular
and such that the centre of curvature lie~ at the centre
of gravity of the concrete elements, only the centre of
gravity of the casting table is lifted during erection.
A relatively small re3toring moment occurs in each case
during lifting and lowering. Since the position of the
centre of gravity of the casting table can be influenced
by constructive measures, the curvature of the runners
and the position of the centre of gravity can be
optimized accordingly. In particular, for reasons of
stability, a restoring moment is ~aintained. In order to
forcefully control the erection proces~, the table 1
has a hook 25 attached to it, in which a cable 26 is
hung by means of an eye. ~he cable 26 runs over rollers
27 to a winch 28 being provided with a ratchet. By
turning the winch the wall can now be raised and the
table, having been drawn off from the wall, can be
lowered again. The curvature of the runners can now be
optimized so that the forces in cable 26 are constant
and minimal. The resulting sled shape is not exactly
circular, and an instantaneous centre curve is formed
by the centre of curvature.
~he claws 18 prevent the pre-cast wall from slipping
prematurely off the casting table during the erection
process When the wall ha~ been lifted into vertical
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position, it stands on the crane beams 9. The lengths
of timber 19 used here as lateral bounding framework
and which are not removed, prevent any escape of the
still-fresh concrete.
The mold framework must now be drawn off from the wall.
Since thc concrete is still fre~h, there is a danger of
its escaping. A device is therefore necessary which
distributes the forces arising during withdrawal over
as large a surface area as possible. This device is
provided by ~upport 10. By turning the threaded rod 13
to the right, it presses against the support 10. Since
this represents the lowest part of the mold framework,
it presses against the wall over its whole length, thus
pulling the framework off. The support must be
sufficiently rigid as to ensure that the bending
occurring in it is small enough to exclude cracks in
the concrete. It serves no purpose however, -to further
increase the rigidity~ since in so doing the forces
necessary for the withdrawal are higher because the
withdrawal process spreads more quickly over the whole
molding surface.
When the ~old framework has been drawn off, the table 1
can be immediately brought into the new position by
turning the threaded rod further until the casting
table has moved far enough away from the wall to make
room for the next wall. If the threaded rod 13 is now
turned to the left, the fixtures 16 press against the
support and draw it away from the wall. Since the endsof
the threaded rod project into the bushings 15, it does
not tip. ~y further turning to the left the table is
pulled back to its starting position. The casting table
is now lowered into the horizontal position and the next
wall or ceiling respectively can be concreted.
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The movable shed 20 is chosen large enough to
accommodate several walls, for ex. a week's production.
This guarantees that the s-till-fresh concrete walls
are not immediately exposed to the weather.
In the case of the rollers 22 there is in each ca~e a
rod 29 connected rigidly -to the shed 20, The rods 29
run parallel to the crane beam~ 9. When the casting
table is in raised positionJ the claws 18 come in
contact with the ends of the rods 29. When the casting
table is pushed back with the help of the withdrawal
device, the claws 18 press against the rods 29 and push
the shed back. The rod is provided with horizontal
holes 30~ ~he distance between these holes corresponds
to the breadth of space required for each concrete
element. There are cylinder holes 31 in the crane beams,
occurring at intervals which are a multiple (e.g, ~ 6)
of the hole intervals in the rod 29. ~he cylinder holes
in the rod and in the crane beams are in alignment, '~he
casting table is now pushed back until the cylinder holes
match and a bolt 32 is pushed in. In this way undesired
lateral displacements of the shed 20 are prevented. lhis
is necessary since during the erection proce~s by the
cable 26 horizontal forces are exercised on the shed.
Furthermore the bolt secures the shed on the side of
the rollers 22 agalnst any lifting and an exact measure
of how far the casting table must ~e pushed back in each
case is achieved. ~he rollers 22 and/or 21 can possibly
be omitted since with the help of the withdrawal device
large forces can be exercised. ~he shed is then moved by
sliding on its bearing surfaces. At the side of the
erected walls the shed can be secured agalnst lifting
by hanging the cable 26 on the underside of the last
wall and drawing it tight with the winch 28.
For the manufacture of ribbed walls, inserts 3~ are
laid on after the casting of the continuously smooth
wall component. ~hese inserts consist preferably of
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sheets 34 which are bent to a trape~oidal- haped hollow
body. The hollow body is filled with hard-foam plates
and covered at the top with sheets 35, the~e being
screwed to the sheets 34 to prevent any displacement.
~ight insert pieces of high ri~idity result. These
in~erts ~ are connected to a continuous grillage 40
by means of two beams, preferably wooden pin girders,
36. The grillage is hung from the ceiling of the ~hed 20.
Rollers 37, 38 and 39 are attached to the ceiling of the
shed 20 above one corner of the casting table as well as
above the centre of each of the understructures 2. ~en
the grillage 40 is to be removed after concreting of the
column, the cable 26 is first pas;sed over the roller 37
and hung onto a corner of the grlllage 40. With the
help of the winch 28 a corner of the grillage i5
raised and loosened from the groined ceiling. The cable
is now hung around the roller 38. The roller 38 i~ the
; roller lying nearer to the rciler 37. Since the grillage
has already been loosened here the one side of the grillage
can now be raised to the ceiling and hung from hereO
The cable can now be hung around roller 39 and the other
side of the grillage can be raised and hung.
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The overarches ofthe pin girders 3~6 are constructed as
approx. 50 cm broad planks, so that they can be uQed as
wheelbarrow tracks. The shed is high enough to provide
standing height above the wheelbarrow tracksO ~he
concrete i~ mixed with the help of a mixer having a
hoist, The hoi~t is high enough for the wheelbarrow to
be filled at the level of the wheelbarrow tracks. The
only further requirement is to lay wheelbarrow tracks
from the mixer to the tracks 41 90 as to enable the
elements to be concreted. If the tracks 41 are
connected with one another in each case at the end of
the grillage, a rotary worXing can be set up which
guarantees a frictionless concrebing operation.
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