Note: Descriptions are shown in the official language in which they were submitted.
CA 02747671 2011-06-17
CONTAINER WALL FOR A CONTAINER COVERED BY A FOIL AND
OUTER FORMWORK FOR PRODUCING THE CONTAINER WALL
The invention relates to a container wall according to claim 1 or 3 and an
outer
formwork for producing the container wall according to claim 22.
Container for storing and fermenting of ferments, for example in so-called
biogas plants
have considerable dimensions. They are mostly designed silo-like and thus have
mostly a
circular base. The wall is for example cast from concrete and the sealing to
the top is
often realized by a roof shaped foil, which is held in a tense and raised
state by gas
production or by a introduction of compressed air. For the secure fixation of
the foil at
the rim to the container wall, it is also known to install a clamping profile
to the upper
outer portion of the wall, into which the foil can be inserted and be affixed
by the use of
a clamping tube.
From DE 10 64 869 A it is known, to insert the rim of a foil that seals a
container to the
top into a circumferential slot that has a U-shaped cross section and
subsequently
inserting an inflatable tube in order to fixate the rim of the foil. From DE
10 2006 035
227 B3 it is known, to attach a gas container as well as a covering hood from
foil
material in a C-shaped rail that is mounted to the outside of the container,
wherein a
clamping tube is inserted to the rail for the fixation of the foil inside the
rail.
Depending on the prevailing gas pressure in the container, the supporting air
pressure or
the external influences, corresponding tensile forces are introduced into the
rail via the
foil. There is therefore the risk that the foil slips out of the rail due to a
deformation of
the clamping profile or a lack of clamping force.
This can as well be counteracted in practice by solid flanging of the foil(s)
to the
container. The foil can be loaded until disruption. Disadvantageous is the
additional
effort for opening the cover, for example for maintenance purposes. In
addition the cover
can lose its function when the foil ruptures, which must be avoided.
The objective of the invention is to create a container wall for a container
with a device
for fixating a foil made of plastic material that seals the container roof-
like at the top,
which can easily be manufactured and assembled and especially also can
withstand high
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tensile forces at the foil. A further objective is to create a simple outer
formwork for a
container wall.
This objective is solved by the features of claim 1 and 3 or claim 21
respectively.
For the inventive container wall, which is preferably made of concrete, at the
top section
a clamping channel is provided that is open to the outside with a preferably
lateral
insertion slot, which height is less than the height of an oblong insertion
profile, to which
the foil can be wrapped around, that can be inserted into the clamping
channel.
According to an embodiment of the invention the lower wall of the clamping
channel is
just slightly wider than the thickness of the insertion profile at the facing
longitudinal
edge which is, for example formed as a flat profile, while the upper wall of
the clamping
channel is at least twice as wide as the thickness of the flat profile at the
facing
longitudinal edge. The insertion profile with the foil wrapped around is
tilted towards the
insertion slot through this inserted into the clamping channel and
subsequently for
example placed into a vertical position, so that with tensile forces at the
foil it is pressed
from inside against the protrusions which limit the insertion slot. High
tensile forces can
be absorbed with the help of such a construction without facing the risk that
the foil slips
out of the clamping channel. According to an embodiment of the invention the
insertion
profile comprises a predetermined breaking point, wherein it bents essentially
around a
horizontal axis when a predetermined maximal force acts on the foil. The
insertion
profile is preferably made of flat material, for example from sheet steal or
plastic. It can
be formed as a flat strip or bent or broken or it can be a more or less flat
profile strip. The
flat strip can have a rectangular, trapezoidal or angular cross section.
Depending on the pressure conditions in the container and the wind force that
acts on the
roof foil considerable tensile forces are exerted on the foil rim. The risk is
therefore, that
the foil rim is being pulled out when the tensile forces exceed a certain
value. This risk is
increased, when the angle of the foil rim to the associated leg of the rail-
shaped clamping
profile takes up a larger value, so that the leg undergoes a deformation and
is bent
upwards and the traction between foil rim and clamping profile is reduced.
In the solution according to claim 3 it is ensured that especially for higher
tensile forces
on the foil the tensile force acting on the facing upper leg essentially
introduced as a
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compression force to the leg and acts only as a smaller bending moment on the
leg. Thus
there is no disadvantageous deformation of the clamping profile with the
result that the
foil rim is being pulled out.
Viewed in the cross section, the insertion slot of the clamping channel lies
in a plane,
which is obliquely directed downward, which means it lies in an acute angle to
the
overlying container wall. If the pressure in the container increases, this
leads to a raising
of the roof foil, whereby the angle is increased. This reduces the pull-out
force at the
clamping profile. By a tilting of the clamping profile, however a greater pull-
out
resistance is acquired. The foil rim for example extends in an angle of 30 to
45 to the
horizontal. The leg of the clamping profile facing the foil rim preferably
extends in the
same angle. Thus, with the invention also with higher values of the pull-out
force a
secure anchorage of the foil rim is assured.
In an embodiment of the invention the clamping channel or the clamping profile
respectively is formed by profile rail, which is U-shaped or preferably C-
shaped in the
cross section and preferably arranged tilted. The container wall is preferably
formed
from concrete and the rail can be cast into the concrete wall.
Alternatively such a profile rail can be mountable to the outside of the
container wall.
There are different design options. According to an embodiment of the
invention one
option is, that vertical mounting sections are attachable in intervals on the
outside of the
container wall, which preferably comprise a recess adapted to the cross
section of the
rail, in which the profile rail is inserted tilted and fixed, preferably by
welding. The rail
that is preferably made of longitudinal sections, which are subsequently
connected to
each other, is first bent and than positively connected to the mounting
sections. These are
then connected to the container wall, for example by suitable anchors. In a
further
embodiment of the invention in this regard it is intended, that the mounting
section is U-
shaped in the cross section, wherein the recess is formed in the legs and the
web of the
mounting section is connectable with the container wall.
Alternatively, a holding means comprise an angle profile, which is for example
welded
to the rail, wherein the angle profile is mountable to the outer wall of the
container.
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The clamping profile in the form of a profile rail which is preferably C-
shaped in the
cross section, can be cast into the container wall. In this solution according
to the
invention a high pull-out force can be also obtained, if the clamping profile
is arranged a
certain distance to the upper edge of the container wall. A deformation of the
leg of the
rail facing the foil rim is no risk.
In a further embodiment of the invention the upper edge or the upper leg of
the profile
rail is flush with the top of the container wall. In a further embodiment of
the invention,
the top of the container wall can rise towards the outside.
If the clamping profile or the profile rail respectively is cast to the
container wall in a
distance to the top of the container wall, the outer upper edge of the wall is
rounded
according to a further embodiment of the invention. In this way the foil is
not loaded as
much.
As already indicated, the invention is particularly advantageous, if the
profile rail is in a
tilted position, to increase the pull-out force and to reduce the bending load
at the
associated leg respectively. At the profile rail mounted to the outside of the
wall, the
upper leg is loaded with the tensile force of the foil in particular. The
tensile force
produces a bending moment. The tilted arrangement allows an extension of the
leg of the
profile rail facing the foil in a direction approximately parallel to the foil
or in only a
small angle to it. Thus a small-scale profile rail can be used to achieve the
same pull-out
forces as in conventionally mounted profile rails whose insertion slot is for
example in
the vertical or whose upper leg forms a larger angle to the foil respectively.
With an
integration of a profile rail into the material of the container wall the
thickness of the
material of the profile rail, which is preferably formed from flat material,
can be very
small, since the forces are largely absorbed by the surrounding material of
the container
wall. Also with the arrangement of the profile wall in recesses of vertical
mounting
sections it is ensured that a significant resistance is opposing the bending
of the upper leg
of the profile rail, whereby the risk of pulling out the foil rim is
considerably reduced.
The invention is also related to an outer formwork for the production of a
container wall
from concrete. With the help of a formwork a clamping profile can be easily
produced in
the concrete wall. According to the invention, one option is that a profile
rail which is U-
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or C-shaped in the cross section is detachably mountable to the outer formwork
elements, wherein the connection between these parts is accessible from the
outside.
When filling the formwork with concrete, the profile rail is automatically
embedded in
the wall. Before removing the formwork, the connection of the other formwork
with the
profile rail is released. The profile rail can also be mounted to a formwork,
so that the
upper leg is approximated to the extension direction of the foil or its
insertion slot in the
cross section respective extends in a plane that is obliquely directed
downward.
In general according to the invention it is also possible, to form the
clamping profile by a
suitable positive profile on the outer formwork. Synthetic material used for
the positive
profile can be removed with heat and/or chemical substances, so that a
clamping channel
is formed in the wall for the fixation of the foil rim with a suitable
clamping element.
The clamping element is either an inflatable clamping tube or the already
mentioned
insertion profile to which the foil rim is wrapped around. In the event of a
tensile force
the foil rim together with the clamping element is applied against the inside
of the
clamping profile or its protrusions in the area of the insertion slot.
According to an embodiment of the invention the attachment means comprise at
least
one hole at the top of the formwork elements as well as a plug- or screw
connection for a
profile holder, which in turn is designed so that it temporarily fixates a
profile rail or a
formwork rail to the formwork element before filling in the concrete and after
filling the
concrete a profile rail or a formwork rail can be brought out of engagement
with the
formwork element by releasing the attachment means and tilting movement with
the
profile rail or the formwork rail respectively. For this purpose the profile
holder can
comprise a first sheet-metal portion, which in an approximately right angle to
the
insertion slot engages behind the foil limiting protrusions of the profile
rail or of the
formwork rail from the inside and comprising a transversally thereto disposed
second
sheet-metal portion, which is placeable on top of the formwork and comprises a
mounting hole that is aligneable to the hole in the formwork element. The plug
connection can comprise a pin as well as a clamping portion for the clampingly
fixation
of the second sheet-metal portion at the top of the formwork element by
rotation of pin
and clamping element.
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Finally, below the top of the formwork element and below the clamping profile
or the
formwork profile respectively a C-shaped running rail, which is composed of
individual
running rail elements can be connected to the formwork element to embed the
running
rail in the concrete of the container wall. Such a running rail allows the
attachment of a
carriage at the outside of the container wall, wherein it is suspended from
rollers that roll
in the running rail. Such a design possibly spares the attachment of a
platform extending
around the container. The running rail elements can be connected to the
profile rail
elements at the outset, preferably by welding.
Below embodiments of the invention are illustrated by drawings in greater
detail.
Fig. 1 a shows a schematic plan view of a container.
Fig. 1 b shows a section through the illustration according to Fig. 1 along
the
line 2-2.
Fig. 2 shows a detail III according to Fig. 1 b for the fixation of a roof.
Fig. 3 shows a further embodiment for the fixation of a roof foil.
Fig. 4 shows a further embodiment for the fixation of a roof foil.
Fig. 5 shows a further embodiment for the fixation of a roof foil.
Fig. 6 shows a further embodiment for the fixation of a roof foil.
Fig. 7 shows a further embodiment for the fixation of a roof foil.
Fig. 8 shows enlarged for example a profile rail according to Fig. 6.
Fig. 9 shows a profile rail, but on the outside of the container wall in a
tilted
position
Fig. 10 shows an attachment profile for a profile rail according to Fig. 9
Fig. 11 shows indicated an outer formwork for a container wall according to
the invention.
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Fig. 12 shows the attachment of a profile rail to the formwork according to
Fig. 11.
Fig. 13 shows the view of the profile rail according to Fig. 12 in the
direction
of arrow 13.
Fig. 14 to 17 show various views of clamping attachment elements for a profile
holder according to Fig. 12 or 13 respectively.
In Fig. I a and b is indicated a container 10, which base plate 12 comprises
concrete and a
cylindrical wall 14, also made of concrete. The concrete wall is, for example,
made with
a variety of formwork elements which are arranged outside and inside. To the
top at least
one plastic foil 16 is spanned over the container 10, wherein its rim is fixed
at the upper
area on the outside of the wall 14, as will be further described below. In the
container is,
for example, a ferment 18. On the outside of the wall 14, a peripheral
platform 20 with
railings is shown. The platform consists of individual platform elements,
which can also
be connected to each other. The platform is not important for the invention.
In Fig. lb
furthermore is indicated a outer formwork 26 and a inner formwork 27. It
serves, as
mentioned, for the production of the wall, wherein the formwork is removed
after
construction of the concrete wall 14.
In Figure 2 at 110 the upper part of the container wall is shown, as it can be
seen in
Figure 3. It contains a clamping channel 112, that comprises a bottom 114, an
upper wall
116 and a lower wall 118. At the transitions the walls are curved in the cross
section. By
downward and upward pointing protrusions 120 and 121 (in the cross section)
respectively, a narrowed insertion slot 124 is formed to the channel 112. A
clamping
element in form of a flat profile 126 has approximately the same dimensions
over its
height and its thickness and is rounded at the edges. The thickness of the
flat profile 135
is larger than the height of the insertion slot 124 and is sized, so that it
is held by the
inner sides of the protrusions 120, 122, when the flat profile 126 touches the
lower wall
118. This is in its height or width respectively only slightly larger than the
thickness of
the flat profile 126, as can be clearly seen in Figure 2. The upper wall 116
is, however,
significantly higher or wider respectively than the thickness of the flat
profile 126, at
least twice of its thickness. Shown in broken lines, in the pivoted position
of the flat
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profile 126, shown at 126', it can be inserted into the channel 112 via the
insertion slot
124. Before this happens, a foil 130 is wrapped around the flat profile 126.
After
inserting the flat profile 126 with the foil 130 and the placement of the flat
profile 126 to
the wall 118 a tilt back of the flat profile 126 into an approximately
vertical position
parallel to the insertion slot is realized by a pull on the foil 130. Thus the
foil 130 is
clamped in the channel 112 and can not be pulled out.
As can be seen further, the flat profile 116 comprises a notch 132, which
forms a
predetermined breaking point. In case of an accident the predetermined
breaking point as
a last instance prevents a rupture of the foil and can provide emergency
relief.
It is understood, that the clamping channel 112 can also, for example, be
produced from
a separate profile rail, which is further described below. For the fixation of
the foil the
profile of the clamping channel and the clamping element in the clamping
channel are
essential.
In the Figs. 3 - 5 a section through the upper portion of the container wall
14 is shown,
which is, however, structured differently in the upper portion, as described
below. It can
also be seen an outer- and inner formwork 26, 27 according to Fig. lb in
production of
the container wall of concrete.
In Fig. 3 a box-shaped or in the cross section C-shaped profile rail 36 is
shown, which
has, for example, a shape as shown in Fig. 2. This will be further discussed
below. As
can be seen, the profile rail 36 is integrated in the wall 14, so that the
upper side or the
upper leg respectively is flush with the horizontal top of the wall 14. During
the
production the profile rail 36 is detachably connected to the outer formwork
26 (not
shown). After forming the wall 14 naturally the formwork 26, 27 is removed,
wherein
beforehand the detachable connection to the outer formwork 26 is released. The
profile
rail 36 is than connected to the wall 14.
The profile rail consists of individual segments of specific length, which is
preferably
significantly smaller than the circumferential length of the container 10.
Thereby, a rail
segment can be connected to one or more adjacent formwork elements. The
profile rail
36 or its individual segments respectively are provided with anchor portions,
which, as
shown at 38, extend obliquely downward into the wall 14. They are already
located in
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the profile rail 36, when it is mounted to the outer formwork 26. In Fig. 3
arrows 40
indicate the direction of the tensile force of a foil, which is referenced as
16 in Fig. lb. It
is fixated in the profile rail 36. This is further described below. The
different angles of
the pulling direction 40 result from the type of foil (gas storage foil, air-
supported dome)
and structural conditions. Depending on the size of the angle, load and
bending force at
the upper leg of the profile rail are modified.
The embodiment according to Fig. 4 differs to that according to Fig. 3 in that
the profile
rail 36 is embedded in a distance to the top of the wall 14. Again the profile
rail 36 is
first connected to the outer formwork 26. The foil, that is affixed with its
rim in the
profile rail 36, first extents vertically on the outside of the wall 14 and is
guided
obliquely upward on the wall 14 over a rounded edge 42. The edge 42 reduces
the strain
that occurs with the deflection of the foil.
In Fig. 9 or 12 a C-shaped profile rail is shown, the way it can be embedded
in the wall
14 like in the embodiment according to Figs. 3 and 4. Therefore, the details
of this rail
shall be explained below.
The profile rail 18a according to Fig. 9, having a C-shaped cross section,
comprises a
web 20a and two parallel spaced legs 22a, 24a. The legs are bent at 26a. The
profile rail
18a that is shown is slightly tilted with obliquely downward pointing legs
22a, 24a. An
insertion slot 21 (seen in the cross section) is thus in a plane pointing
downward.
In Fig. 5 the profile rail 18a according to Fig. 9 is also embedded in the
wall 14, so that
its upper edge is flush with the top of the wall 14. This top, however,
comprises a slope,
as indicated at 44. The slope is directed to the outside. The clamping rail
18a is in turn
detachably connected with the outer formwork 26, when the wall 14 is produced.
Subsequently this connection is released, so that the outer formwork 26 can be
removed.
A tilted mounting of the clamping profile 18a has the advantage of achieving
significantly higher pull-out resistance for the foil rim and a favourable
strain on the
profile rail. The upper leg is essentially strained in its extending direction
rather than in
bending. Hence the foil rim is held particularly secure in the clamping
profile 18a.
The clamping of a foil 28 in Fig. 9 is done by an inflatable tube 30 that is
inserted into
the clamping channel formed by the C-shaped profile rail 18a and subsequently
inflated.
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The clamping is preferably at the inside of web 20a and legs 22a, 24a as can
clearly be
seen. The inwardly curved portions 26 prevent the tube 30 from being pulled
out of the
clamping rail 18a by a corresponding load.
It is also possible to embed a clamping channel in the concrete wall with a
formwork.
This possibility is indicated in Fig. 8. In Fig. 8 an upper profile portion 50
and a lower
profile portion 52 are provided, which can be connected to each other using a
screw
connection 54. In the area on both sides of the screw connection the profile
portions 50,
52 form a protrusion 56, which, when casting, forms a channel in the concrete
wall 58,
as, for example, is indicated in several of the above figures. It is
understood, that a
plurality of profile portions 50, 52 are provided in circumferential
direction, which can
be connected to each other, namely via screw connections 60 and 62
respectively. The
lower profile portion 52 is also connected via a flange 64 to an underlying
not shown
formwork element by a screw connection 66. After casting and curing of the
concrete for
the construction of the wall 58 the screw connections 54, 60, 62 are released.
The screw
connections 60, 54, 62 comprise a screw bolt 60 and a cap nut 70. As can be
seen, the
cap nuts 70 remain in the wall 58, while the screw bolts 68 are unscrewed.
After
loosening the screw connections first the lower profile portion 52 can be
removed by
oblique lifting and lateral pull and then the upper profile portion 56 is
removed from the
so formed channel by a diagonal motion.
In Fig. 9 the profile rail 18a is mounted to the outside container wall 10a.
At the back of
the web 20a a leg of an angle profile 12 is welded with the wall 10a, as
indicated at 16a.
As indicated at 14a, the other leg of the angle profile 12 is anchored with
the wall IOa in
an appropriate manner.
In Fig. 10 shows again the profile rail 18a according to Fig. 9. It shall
thereby no longer
be described in detail. Fig. 10 also shows a fastening profile 80. It has a
certain vertical
length, of, for example, 0.15 in. In the cross section it is U-shaped with a
web 82 and two
legs, one of which is shown at 84. In the upper area of the fastening profile
80 the legs 84
are provided with a triangular recess 86. The profile rail 18a is inserted and
affixed in
this in a tilted position, for example, in an angle of 45 . The fixation is,
however, done
only after the sections of the profile rail 18a are bent in the correct round
shape,
corresponding to the outer radius of the container, to which the profile rail
18a should be
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mounted. Holes 86a are formed into the web of the fastening profile 80, so
that the
fastening profile 80 can be mounted vertically to the outside container wall,
for example,
the wall I Oa in Fig. 9, by means of screws or anchors respectively.
Instead of embedding a clamping profile in the form of a profile rail in the
wall, a
positive profile of plastic can be attached to the formwork, which is then
removed from
the wall, for example by heat or a reagent. This leaves a clamping profile in
the wall with
the same function as a clamping rail.
In Figs. 6 and 7 other ways to form a clamping profile are indicated. In Fig.
6 an outer
formwork element 40a is detachably connected with a fiber concrete section
42a,
wherein the detachable connection, which must be accessible from the outside,
is not
shown. The fiber concrete section 42a comprises a ready-made channel 44a and
is, in the
casting, embedded in this (wall 14a). The fiber concrete section 42a can be
ready-made.
It can already be connected to the formwork element 40a in a distance, before
it comes to
the work site or it can be connected to the formwork element 40a at the work
site.
For the sake of completeness it should be mentioned, ' that is talked of only
a single
formwork element or profile formwork section. It is understood, that in
circumferential
direction a plurality of outer formwork elements 40a are provided and also a
plurality of
formwork profile sections 42a.
Fig. 7 shows another possibility. Here, a concrete element 46a is put on top
of the
concrete wall 14b, which is provided with clamping channel 44a. The concrete
element
46a is ready-made and comprises reinforcement 48a that is standing downward
and to
the outside, which can be inserted into the soft concrete after casting the
wall 14b, for
connecting the concrete element 46a with the wall 14b.
Fig. 11 shows indicated a formwork 200 for a container comprising a concrete
wall,
namely the outer formwork. The outer formwork consists of lower formwork
elements
202, which are set up in a ring and thereby form the outer wall of the
container, not
shown. On top of the lower formwork elements 202 upper formwork elements 204
are
placed and connected to each other with, for example, screw connections. For
this
purpose the formwork elements 202, 204 comprise aligned mounting holes 206 and
208
respectively. The upper formwork elements 204 form the upper rim of the
container.
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They also have holes at the top, one of which is shown at 210. In addition,
Fig. 11 shows
a sheet-metal portion 212 that can be mounted on top of the formwork elements
204.
In Fig. 12 an upper outer formwork element 204 is indicated and also the sheet-
metal
portion 212 with its mounting hole 214. It can be seen that a vertical sheet-
metal portion
216, which comprises a rectangular slot 218 at the upper end and a protrusion
220 at the
lower end, is welded to the horizontal sheet-metal portion 212. In Fig. 12
also the cross
section of a profile rail 222 is indicated, which has the form of a slightly
compressed C-
profile with a sloping upper wall 224 or leg, a substantially curved lower
wall 226 or leg
and a bottom 228. The dimensions of the upper and lower wall are such that the
width of
the clamping channel 230 inside the profile rail 222 is considerably larger in
the upper
area than in the lower area. For this purpose also the bottom 228 is arranged
at an angle.
The cross section of the clamping channel 230 is similar to that of Fig. 2,
wherein unlike
in Fig. 2 the upper wall 224 runs obliquely upwards. This provides the
advantage that the
profile rail 222, as shown in Fig. 9, can absorb the tensile force from the
foil, not shown,
as compressive load in the upper leg 224. The clamping channel 230 is adapted
to
receiving a flat profile (as per Fig. 2) to affix a foil in the clamping
channel 230.
The sheet-metal portion 212, 216 are part of a profile holder, to hold the
profile rail 222
at the formwork element 204 before embedding in the wall 232. With the help of
a
device, shown in Figs. 14 to 17, a profile holder can be effectively attached
to the
formwork element 204. For this purpose the device according to Figs. 14 to 17
comprises
a pin 240 that is affixed to an angle section 242 of sheet-metal, for example
by welding.
On the leg of the angle section 242 away from the pin 240 a slot 244 is
formed. A handle
portion 246 is connected to the angle section 242. For the attachment of the
sheet-metal
212 to the sheet-metal portion at the top of the formwork element 204 the pin
is inserted
through the holes 214, 210. Thus the slot 244 is oriented approximately to the
sheet-
metal portion 212 and the sheet-metal of the formwork element 204. By an
appropriate
rotation of the device according to Figs. 14 to 17 the slot is placed over the
associated
sheet-metals, which are thereby clamped against each other. In this way the
profile
holder is securely fixed to the formwork element but can be also easily
removed.
As further shown in Fig. 12, here a concrete wall 232 is already created,
wherein the
inner formwork elements are not shown. The concrete wall comprises
reinforcements
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252. In addition it can be seen that a running rail 254 with a C-section is
connected to the
underside of the profile rail 222 by welding. It is therefore also be held by
the profile
holder until the concrete is cured. The running rail 254 is used to hold one
or more
rollers 256 for a not shown carriage that is suspended on the outside of the
wall 232 and
can be run around the container using the running rail 254.
