[0001] The present application relates to a weight reduction element for the construction
industry, such as a disposable formwork, made of plastic material, optionally recycled,
particularly adapted for use in the creation of weight-reduced roofings or for weight-reduced
foundation concrete beds.
[0002] Nowadays the use is known of disposable formworks made of plastic material for creating
weight-reduced roof slabs and beds of reinforced concrete, the purpose of which is
to provide a weight-reduced roofing or foundation beds of high thickness with considerable
saving of concrete or to provide roof slabs of great span and/or great reach.
[0003] For example a product is known, sold with the U-BOOT trademark, which has been the
subject matter of the filing of
Italian patent no. 1329446 filed on 05/12/2001 with application
PN2001A000085 and granted on 28/10/2005 and having as its title "disposable formwork for the construction of roof slabs,
for use in the construction industry".
[0004] The subject matter of this prior art is a disposable formwork, preferably made of
recycled plastic material, for the in-situ manufacturing of roof slabs, for use in
building constructions that consist of plates of reinforced concrete, simple or with
reinforcing bars, and which constitute the supporting structure of various construction
elements like roofings, bridges, foundations and the like.
[0005] Such known art claims a disposable formwork in plastic material for the in-situ manufacturing
of roof slabs for use in building constructions, which is constituted by a single
hollow body in which the cavity is open downward and which is provided with feet on
its lower edge, the hollow body being shaped like a truncated pyramid with the apex
pointing upward, and in which the lateral surfaces have hollowed-out pilasters and
the upper surface is divided into contoured sectors with a plurality of raised portions.
[0006] Such solution has fixed feet, of preset height.
[0007] Also known is the product sold by the firm Ferracin S.r.l. with the trademark "GIU'lì"
or "TOTI" which is constituted by a disposable formwork, open in a downward region,
made of polypropylene and used as a modular element for making foundation beds and
mono- or bi-directional roofings of reinforced concrete.
[0008] In such product, at the corners adjacent to the lower opening and arranged outside
the inclined side walls thereof, ordinary through holes are provided into which hollow,
conical feet with a circular base are inserted by force. The feet have, at their circular
end, deformable longitudinal seats for the forced mating of the foot at the holes.
[0009] Here again, the feet have a preset height, and the formworks are shipped with the
feet put on at the factory, and in situ they assume a single, fixed position.
[0010] In both of the known solutions indicated, there is a problem in achieving the desired
weight reduction: in fact the height of the weight reduction element and the height
of the foot determine a combination of two variables that, during production, results
in a high number of hours worked, thus increasing the overall cost of the invention.
[0011] Another drawback consists in that when making a roofing, unforeseen circumstances
can arise on the site which require the formworks to be replaced, necessitating the
use of higher or lower feet, with the consequent need to remove the formworks already
produced and quickly replace them, and this inconvenience is exacerbated if the project
is overseas, with possible and expensive site stoppages.
[0012] Another drawback, and certainly the most acute of all, consists in that there may
be, in the erection of the works described above, points of interference between the
feet and the reinforcement frames arranged below the weight reduction element, i.e.
arranged on the provisional slab deck constituted by planks of wood or metal panels,
even if they are slightly spaced apart from it by way of the interposition of spacers.
[0013] It should be noted that the concrete has to completely envelop/embed/cover the reinforcement
bars for structural reasons, for reasons of preservation (exposed or poorly-covered
iron will rust, resulting in swellings that cause the separation of portions of agglomerate),
and for resistance to fire.
[0014] "Minimum cover" is an ever-present aspect, and is strictly controlled by all technical
regulations on construction projects.
[0015] "Exposed" (i.e. visible) iron frames that are not sufficiently "embedded" and therefore
protected by the concrete will compromise the performance of the structure.
[0016] This applicant has filed
Italian application TV2012A0000095 which claims a weight reduction element for the construction industry that
[is] constituted by a first disposable formwork, shaped substantially like a truncated
pyramid, which has, in a region that curves inward with respect to the corners of
the smaller surface, feet, fixed and protruding, which are provided with one or more
first holes or openings and/or, at said smaller surface, with one or more second holes
or openings and/or, at at least one of the lateral surfaces adjacent to said smaller
surface, with one or more third holes, said feet of said first disposable formwork
and said smaller surface being completely or partially embedded during the provision
of a prefabricated slab for roofings.
[0017] Such solution is used predominantly in the provision, in situ, of weight-reduced
bidirectional plate slab roofings (also known as plate slab roofings with hollow bodies
or with hollow cells or by other names) or of weight-reduced foundation beds.
[0018] This solution also presents the drawbacks described previously: the height of the
weight reduction element and the height of the foot determine a combination of two
variables that, during production, results in a high number of hours worked, thus
increasing the overall cost of the invention.
[0019] There is still the drawback due to possible unforeseen circumstances arising on the
site which require the formworks to be replaced, necessitating the use of higher or
lower feet, with the consequent need to remove the formworks already produced and
quickly replace them, and this inconvenience is exacerbated if the project is overseas,
with possible and expensive site stoppages.
[0020] It has also been found that there can be points of interference between the free
ends of the feet or the lower portion thereof and the reinforcement frames arranged
below the weight reduction element, i.e. arranged on the provisional slab deck constituted
by planks of wood or metal panels.
[0021] Often the need to use different feet arises from the difficult, or incorrect, assessment
of the encumbrances (or thicknesses) that are created by virtue of the overlapped
parts of the "reinforcement meshes".
[0022] This is partly because the contracting company often makes changes, or substitutions,
in the types of bars specified at the design stage, leading to possible problems in
observing the "minimum bar-covering thickness".
[0023] In fact the lower reinforcement frames, which are present in massive form, are usually
constituted by electrowelded meshes with square links (or, more rarely, by loose bars
or even by a combination of links and loose bars); the presence of such electrowelded
meshes often entails an "interference" between the feet of the weight reduction element
and the bars of iron of the reinforcement mesh.
[0024] It should be noted that the weight reduction element must maintain a preset position
according to the design specifications, and the presence of the reinforcement mesh.
[0025] As a consequence of this, either the formwork ends up resting unevenly (it is raised
with respect to the intended resting surface) or it is moved laterally, thus losing
the correct "design" position and therefore altering (with an increase or a decrease)
the thickness of the beam (rib) being created between one weight reduction element
and the next.
[0026] In other cases, the foot may press the mesh downward, with the risk that the specified
minimum bar cover is not met, or it may even create a point of contact with the reinforcement
mesh, thus preventing the total and proper "embedding" thereof in the concrete.
[0027] Also known is European patent
EP2530220A1, which discloses a formwork 1 shaped substantially like a truncated pyramid, provided
with legs 4, at its lower surface, which are adapted to be coupled to the formwork
1 by way of a separator system 18 that entails that the free ends 42 of the legs 4,
which have a tubular shape structure, are engaged by pressure on respective studs
21, which protrude outward from the bottom 3 of the formwork 1, and which also have
a tubular shape structure with a slightly smaller diameter than that of the free end
42 of the feet 8 in order to enable the coupling thereof.
[0028] In order to achieve the coupling between the leg 4 and the formwork 1, each free
end 42 of the leg 4 is therefore forced by interference fit into the repeating stud
21 in the bottom 3 of the formwork 1; once the leg 4 is connected to the stud 21,
the orientation of the leg 4, which can be coupled once only, therefore cannot be
changed and/or deviated.
[0029] It has therefore been found in this case too that during the use of the formwork
1 in the production of roofings, points of interference can be created between the
feet 4 and the reinforcement frames arranged below the weight reduction element, on
the provisional slab deck, leading to the many and varied drawbacks explained above.
[0031] Such document relates to a formwork 10 defined by a dome 11 from which extend, sidewise
and downward, four legs 12; on the lower end of each leg 12 there is an integral fork
16, protruding and open downwards, which follows the profile of the leg 12 and fits
on the upper rim of a tubular element 17 (or foot), which is arranged in vertical
position.
[0032] The connection mortised of the fork 16 of the formwork 10 with the tubular elements
17 therefore also does not allow the once-off orientation of the tubular elements
17 to be changed and/or deviated.
[0033] In this case too, during use of the formwork 10, of points of interference can therefore
be created between the tubular elements 17 and the reinforcement frames arranged below
the weight reduction element, leading to the many and varied drawbacks explained above.
[0034] The principal aim of the present invention is therefore to resolve the above mentioned
technical problems, eliminating the drawbacks in the cited known art and hence providing
an invention that makes it possible to obtain, using disposable formworks made of
plastic material, a weight-reduced roofing or weight-reduced foundation beds of high
thickness with considerable saving of concrete, such formworks being at the same time
usable rapidly and at low cost as a function of an intentional and contingent height
of the feet, even if this is different from the design height.
[0035] Within the above aim, another important object of the invention is to provide an
invention that can be used while preventing points of interference between the free
ends of the feet or parts of the feet and the reinforcement frames arranged below
the weight reduction element.
[0036] Another object is to obtain a formwork that always rests optimally with respect to
the intended resting surface and observing the exact design placement thereof.
[0037] Another object is to provide an invention that is structurally simple and convenient
to use and which can be provided with the usual conventional systems.
[0038] This aim and these and other objects which will become better apparent hereinafter
are achieved by a weight reduction element 1 for the construction industry, having
the features of claim 1.
[0039] Further characteristics and advantages of the invention will become better apparent
from the detailed description of a particular, but not exclusive, embodiment of the
invention, which is illustrated by way of nonlimiting example in the accompanying
drawings wherein:
Figure 1 is a perspective view from above of the weight reduction element arranged
above a weight reduction reinforcement mesh;
Figure 2 is a perspective view from below of the weight reduction element;
Figure 3 is a side view of the weight reduction element;
Figure 4 is a detail of a corner of the weight reduction element and a foot;
Figure 5 is a side view of the weight reduction element, in the foot region;
Figure 6 is a cross-sectional view taken along the line VI-VI in Figure 5;
Figures 7 and 8 are two side perspective views of a single foot;
Figure 9 is a view from above of a foot;
Figures 10 and 11 are two side views of a single foot;
Figure 12 is a view from above of a foot coupled to a corner of the weight reduction
element;
Figure 13 shows Figure 1 in a perspective view from below.
[0040] In the embodiments illustrated below, individual characteristics shown in relation
to specific examples may in reality be interchanged with other, different characteristics,
existing in other embodiments.
[0041] With reference to the figures, the reference numeral 1 generally designates a weight
reduction element for the construction industry, constituted by a disposable formwork
2, shaped substantially like a truncated pyramid, made of plastic material, particularly
adapted for use in the provision of weight-reduced bidirectional plate slab roofings
(also known as plate slab roofings with hollow bodies or with hollow cells or by other
names) or of weight-reduced foundation beds by way of the addition of reinforcement
frames 3.
[0042] The disposable formwork 2 is internally hollow and is provided with an upper surface
4, substantially flat, from which variously shaped lateral surfaces 5 extend and are
blended at the tip by a first, perimetric ridge 6, which defines a lower opening 6a.
[0043] It should be noted that the weight reduction element can also be composed of a "closed
shell" i.e. a shell formed by two half-shells (which may be of different heights),
such as for example contained in patent no.
1412724 filed in the name of this applicant.
[0044] The perimetric ridge 6 is such as to allow the coupling of the two half-shells, mentioned
above, so as to obtain a weight reduction element, internally hollow but in the form
of a "closed shell".
[0045] The feet, in this case, no longer extend in a position along the perimetric ridge
6 but are associated proximate to the corners 107 of the upper surface 4 [for example
of the lower half-shell that constitutes the formwork 1].
[0046] Such lateral surfaces 5 have a chosen shape structure and in any case have a chosen
inclination, all in order to make it possible to stack it with other, similar formworks.
[0047] The disposable formwork 2 is internally hollow and open downward, because it lacks
a surface that connects the perimetric ridge 6.
[0048] The disposable formwork 2, at the corners 7 and internally with respect to the first,
perimetric ridge 6, can be detachably associated with the feet 8, of a chosen height,
which, once associated with the disposable formwork 2, protrude on the side opposite
to that of the upper surface 4.
[0049] The feet 8 determine the formation, according to a determined thickness, of the lower
slab (intrados slab) by virtue of the flow of concrete underneath the weight reduction
element.
[0050] The feet 8 have a parallelepiped shape, preferably conical with a circular base,
and are preferably internally hollow.
[0051] At the corners 7 of the disposable formwork 2 there are therefore first holes 9,
preferably circular, proximate to which are engagement means 10 for temporarily stable
interconnection with grip means 11 associated with the free upper end 12 of each foot
8.
[0052] For a "closed shell" formwork, proximate to the corners 107 of the upper surface
4, engagement means 110 (stylized in Figure 1) that are similar, in shape and function,
will be associated with the engagement means 10.
[0053] The engagement means 10 enable a connection that is stable with the disposable formwork
2 and at the same time removable for an optional stable repositioning of the foot
8 in another angular position.
[0054] At the free upper end 12 there is a flat disk 13 with a circular plan shape, which
abuts, once the foot 8 is coupled to the disposable formwork 2, against a complementarily
shaped bottom 14 that surrounds each first hole 9.
[0055] The temporary engagement means 10 are constituted by a second, annular ridge 15,
which surrounds the hole 9 and protrudes upward with respect to it, is of a chosen
height, and is arranged concentrically and internally to a cylindrical tab 16, which
is provided on each corner 7 proximate to the first, perimetric ridge 6.
[0056] The grip means 11 are associated with a third, annular ridge 17, which protrudes
axially both with respect to the first hole 9 and with respect to the flat disk 13;
such third, annular ridge 17 has an outside diameter that is smaller than the inside
diameter of the second, annular ridge 15 and a slightly greater height than the latter,
so that the tip 18 of the third, annular ridge 17 protrudes beyond the corresponding
tip of the second, annular ridge 15.
[0057] The third, annular ridge 17 advantageously has an angular extension of approximately
270°.
[0058] The grip means 11 are associated with the tip 18 and are constituted by one or more
teeth 19 that protrude radially and externally to the third, annular ridge 17 and
interact in abutment with the underlying second, annular ridge 15.
[0059] Advantageously the teeth 19 are three in number and are angularly mutually spaced
apart by approximately 120°.
[0060] Alternatively it is possible to provide a single tooth that runs along all 270° of
the third, annular ridge 17.
[0061] Each foot 8 has a conical body 20 that protrudes below, and eccentrically with respect
to, the flat disk 13.
[0062] The central axis 21 of the flat disk 13, which coincides with the axis of the first
hole 9, is therefore distinct from the central axis 22 of the body 20; it follows
from this that the lower end 23 of the body 20 is axially offset with respect to the
grip means 10.
[0063] The body 20 can have the desired shape structure; for example it can be composed
of two or more elements with two or more separate lower ends 23, for example so as
to define a "spider legs" type of shape structure.
[0064] This means that, once the third, annular ridge 17 of each foot 8 is inserted into
the first hole 9, the foot 8 can be rotated until the lower end 22 of the body 20
is positioned at the desired point so as to not interfere with the reinforcement frames
arranged below the weight reduction element.
[0065] The connection between each foot 8 and the disposable formwork 2 is obtained by making
one or more of the teeth 19 interact with the second, annular ridge 15.
[0066] Advantageously, voids 24 of material are provided on the flat disk 13 at each overlying
tooth 19 in order to facilitate the connection between the components.
[0067] Advantageously the third, annular ridge 17 has a partial covering 25 at which adapted
through seats 26 are perimetrically provided, which are provided at the teeth 19.
[0068] The possibility should furthermore be noted, that is not according to the claimed
invention, of using a single foot 8 arranged at the upper surface 4, preferably in
a central region thereof; in this case too, an adapted circular first hole 9 will
be obtained, proximate to which will be temporary engagement means 10 for rotatable
interconnection with grip means 11 associated with the free upper end 12 of the foot
8, which will have a chosen height and can be conveniently axially offset from the
lower end 23.
[0069] In practice it has been found that the invention has fully achieved the intended
aim and objects, an invention having been obtained that makes it possible to obtain,
using disposable formworks 2 made of plastic material, a weight-reduced roofing or
weight-reduced foundation beds of high thickness with considerable saving of concrete
as a function of an intentional and contingent height of the feet, even if this is
different from the design height.
[0070] The rapid and easy interchangeability of the feet 8 in fact makes it possible to
limit the number of versions to be provided and to contain the costs of producing
and managing the formworks, since it is possible to provide a formwork 2 of chosen
height and feet 8 of different heights for mating with the formwork 2 as a function
of the chosen thickness of the intrados slab.
[0071] It is furthermore possible to remedy possible and frequent unforeseen circumstances
that arise on site, or last-minute design errors, simply by substituting only the
feet, of a chosen height, without necessarily having to substitute the whole weight
reduction element.
[0072] The invention furthermore can be used while preventing points of interference between
the free lower ends 23 of the feet 8 or the surfaces 20 of the feet 8 and the reinforcement
frames 3 arranged below the weight reduction element, while always resting the formwork
2 optimally with respect to the intended resting surface on the slab deck and exactly
in the placement specified in the project.
[0073] The offset of the lower end 23 of the foot 8 with respect to the grip means 11 of
the foot and of the temporary engagement means 10, 110 of the formwork 2 in fact allow,
by way of a small rotation imparted to the foot 8 in its grip seat 11, a slight displacement
of its lower end 23: in this manner the formwork 2 makes it possible to prevent any
points of interference between the free lower ends 23 of the feet 8, or the surfaces
20 of the feet 8, and the reinforcement frames 3 arranged below the weight reduction
element 1, it therefore always being possible to rest the formwork 2 optimally with
respect to the intended resting surface on the slab deck and exactly in the placement
specified in the project.
[0074] Naturally the materials used as well as the dimensions of the individual components
of the invention may be more relevant according to specific requirements.
[0075] The various means of achieving certain different functions certainly need not coexist
only in the embodiment shown, but may be present in many embodiments, even if they
are not shown.
[0076] Thus, for example, the stable repositioning of the foot 8 in another, and different
with respect to an initial, angular position with respect to the disposable formwork
2 can be obtained by providing either the engagement means 10 or the foot 8 with removable
diaphragms that are associable respectively either with the grip means 11 or with
the engagement means 10.
[0077] This could allow at least one single repositioning of the foot.
[0078] The characteristics indicated above as advantageous, convenient or the like, may
also be missing or be substituted by equivalent characteristics.
[0080] Where technical features mentioned in any claim are followed by reference signs,
those reference signs have been included for the sole purpose of increasing the intelligibility
of the claims and accordingly, such reference signs do not have any limiting effect
on the interpretation of each element identified by way of example by such reference
signs.
1. A weight reduction element (1) for the construction industry, constituted by at least
one disposable formwork (2), substantially shaped like a truncated pyramid, which
is hollow and has a closed upper surface (4) and a lower opening (6a), said weight
reduction element comprising feet (8) of a chosen height, each foot (8) having a lower
end (23), opposite a free upper end (12),
characterized in that
wherein
- at least proximate to corners (7) of the formwork that are adjacent to said lower
opening (6a) or
- proximate to corners (107) of the formwork (2) of said upper surface (4) and associated
with said formwork, engagement means (10, 110) are provided,
whereby said engagement means (10,110) are stable and substantially rotatable interconnected,
temporarily, with grip means (11) associated with the free upper end (12) of said
feet (8),
and wherein the lower end (23) of each foot (8) is axially offset with respect to
the grip means (11) and to said temporary engagement means (10, 110), respectively.
2. The element according to claim 1, wherein said disposable formwork (2), proximate
to said corners (107) of said upper surface (4), is detachably associated with said
engagement means (110) for temporarily stable interconnection with said grip means
(11).
3. The element according to claim 1, comprising the internally hollow disposable formwork
(2) provided with said upper surface (4), substantially flat, from which variously
shaped lateral surfaces (5) extend and are blended at the tip by a first, perimetric
ridge (6), which defines said lower opening (6a), whereby said disposable formwork
(2), at the corners (7) of the formwork that are adjacent to said lower opening and
internally with respect to said first perimetric ridge (6), are detachably associated
with said feet (8), of a chosen height, which protrude on the opposite side with respect
to said upper surface (4).
4. The element according to claim 1 or 2, wherein at said corners (7, 107) of the formwork
(2) that are adjacent to said lower opening (6a) or said corners of the formwork of
said upper surface (4) there are first holes (9), which have a regular or irregular
polygonal plan shape or are circular, proximate to which are said engagement means
(10, 110), at each free upper end (12) there being a flat disk (13) with a circular
plan shape, which abuts against a complementarily shaped bottom (14) that surrounds
each one of said first holes (9).
5. The element according to claim 4, wherein said engagement means (10, 110) are constituted
by a second, annular ridge (15), which surrounds said hole (9) and protrudes upward
with respect to it, is of a chosen height, and is arranged concentrically and internally
to a cylindrical tab (16), which is provided on each one of said corners (7, 107)
proximate to said first, perimetric ridge (6).
6. The element according to claim 5, wherein said grip means (11) are associated with
a third, annular ridge (17), which protrudes axially both with respect to said first
hole (9) and with respect to said flat disk (13), said third, annular ridge (17) having
an outside diameter that is smaller than the inside diameter of said second, annular
ridge (15) and a slightly greater height than the latter, so that a tip (18) of said
third, annular ridge (17) protrudes beyond the corresponding tip of said second, annular
ridge (15).
7. The element according to claim 6, wherein said grip means (11) are associated with
said tip (18) and are constituted by one or more teeth (19) that protrude radially
and externally to said third, annular ridge (17) and interact in abutment with said
underlying second, annular ridge (15).
8. The element according to claim 4, wherein each one of said feet (8) has a substantially
conical body (20) that protrudes below and eccentrically with respect to said flat
disk (13), the central axis (21) of said flat disk (13), which coincides with the
axis of said first hole (9), being distinct with respect to the central axis (22)
of said body (20), so that said lower end (23) of said body (20) is axially offset
with respect to said grip means (11) and to said engagement means (10, 110).
9. The element according to claim 6, wherein once said third, annular ridge (17) of each
one of said feet (8) is inserted into said first hole (9), a rotation can be imparted
to said foot (8) until said lower end (23) of said body (20) is arranged in the chosen
point so as to not interfere with the reinforcement frames (3) arranged below said
weight reduction element (1).
10. The element according to claim 7, wherein voids (24) of material are provided on said
flat disk (13) at each one of said overlying teeth (19), said third, annular ridge
(17) having an angular extension of approximately 270° and said teeth (19) being three
in number and mutually angularly spaced apart substantially by 120°.
1. Ein Gewicht Reduktionselement (1) für die Bauindustrie, dass aus mindestens einer
Wegwerfverschalung (2) besteht, die im Wesentlichen wie eine Kegelstumpf Pyramide
geformt ist, welche hohl ist und eine geschlossene obere Oberfläche (4) und eine untere
Öffnung (6a) hat, wobei das Gewicht Reduktionselement Füße (8) mit einer gewünschten
Höhe umfasst, wobei jeder Fuß (8) ein unteres Ende (23) gegenüber einem freien oberen
Ende (12) hat
dadurch gekennzeichnet, dass
- mindestens angrenzend an Ecken (7) der Verschalung, die an die untere Öffnung (6a)
angrenzen, oder
- angrenzend an Ecken (107) der Verschalung (2) der oberen Oberfläche (4) und mit
der Verschalung verbunden,
Eingriffsmittel (10, 110) bereitgestellt sind,
wodurch die Eingriffsmittel (10, 110) stabil und im Wesentlichen drehbar vorübergehend,
mit Greifmitteln (11) verbunden sind, die mit dem freien oberen Enden (12) der Füße
(8) verbunden sind und wobei, das untere Ende (23) jedes Fußes (8), axial von den
Greifmitteln (11) beziehungsweise den vorübergehenden Eingriffsmitteln (10, 110) versetzt
ist.
2. Das Element gemäß Anspruch 1, wobei die Wegwerfverschalung (2), nahe den Ecken (107)
der oberen Oberfläche (4), zur vorübergehenden festen Verbindung mit den Greifmitteln
(11) lösbar mit den Eingriffsmitteln (110) verbunden ist.
3. Das Element gemäß Anspruch 1, dass die innen hohle Wegwerfverschalung (2) umfasst,
die mit der im Wesentlichen flachen oberen Oberfläche (4) versehen ist, von welcher
sich verschieden geformte Seitenflächen (5) erstrecken und an der Spitze in einen
ersten Umfangsgrad (6) übergehen, der die untere Öffnung (6a) bestimmt, wodurch die
Wegwerfverschalung (2) an den Ecken (7) der Verschalung die an die untere Öffnung
angrenzen und innerhalb des ersten Umfangsgrads (6) liegen, lösbar mit den Füßen (8)
einer gewünschten Höhe verbunden sind die an der, der oberen Oberfläche (4) gegenüberliegenden
Seite vorstehen.
4. Das Element gemäß Anspruch 1 oder 2, wobei sich an den Ecken (7, 107) der Verschalung
(2), die an die untere Öffnung (6a) angrenzen oder an den Ecken der Verschalung der
oberen Oberfläche (4) erste Löcher (9) befinden, die einen regelmäßigen oder unregelmäßigen
vieleckigen Grundriss haben oder kreisförmig sind und in deren Nähe sich Eingriffsmittel
(10, 110) befinden, wobei sich an jedem freien oberen Ende (12) eine flache Scheibe
(13) mit kreisförmigen Grundriss befindet, die an einen komplementär geformten Boden
(14) anstößt, der jedes der ersten Löcher (9) umgibt.
5. Das Element gemäß Anspruch 4, wobei die Eingriffsmittel (10, 110) aus einem zweiten
ringförmigen Grad (15) bestehen, der das Loch (9) umgibt und mit Bezug auf dasselbe
vorsteht, eine gewünschte Höhe hat und konzentrisch und innerhalb eines zylindrischen
Vorsprungs (16) angeordnet ist, welcher an jeder der Ecken (7, 107) angrenzend an
den ersten Umfangsgrad (6) angebracht ist.
6. Das Element gemäß Anspruch 5, wobei die Greifmittel (11) mit einem dritten, ringförmigen
Grad (17) verbunden sind, welcher sowohl mit Bezug auf das erste Loch (9) als auch
mit Bezug auf die flache Scheibe (13) axial vorsteht, wobei der dritte ringförmige
Grad (17) einen Außendurchmesser hat, der kleiner ist als der Innendurchmesser des
zweiten ringförmigen Grads (15) und eine etwas größere Höhe als dieser, so dass eine
Spitze (18) des dritten ringförmigen Grads (17) über die entsprechende Spitze des
zweiten ringförmigen Grads (15) vorsteht.
7. Das Element gemäß Anspruch 6, wobei die Greifmittel (11) mit der Spitze (18) verbunden
sind und aus einem oder mehreren Zähnen (19) bestehen, die radial außerhalb des dritten
ringförmigen Grads (17) vorstehen und im Widerlager mit dem darunterliegenden zweiten
ringförmigen Grad (15) zusammenwirken.
8. Das Element gemäß Anspruch 4, wobei jeder der Füße (8) einen im Wesentlichen kegelförmigen
Körper (20) hat, der unterhalb und exzentrisch zu der flachen Scheibe (13) vorsteht,
wobei die Mittelachse (21) der flachen Scheibe (13), die mit der Achse des ersten
Lochs (9) zusammenfällt, nicht identisch mit der Mittelachse (22) des Körpers (20)
ist, so dass das untere Ende (23) des Körpers (20) axial zu den Greifmitteln (11)
und zu den Eingriffsmittel (10, 110) versetzt ist.
9. Das Element gemäß Anspruch 6, wobei, sobald der dritte ringförmige Grad (17) jedes
der Füße (8) in das erste Loch (9) eingesetzt ist, dem Fuß (8) eine Drehung verliehen
werden kann, bis sich das untere Ende (23) des Körpers (20) in den gewählten Punkt
befindet, um die Verstärkungsrahmen (3) die Unterhalb des Gewichtsreduktionselements
(1) angeordnet sind, nicht zu behindern.
10. Das Element gemäß Anspruch 7, wobei an jedem der darüberliegenden Zähne (19) Hohlräume
(24) von Material, in der flachen Scheibe (13) angebracht sind, wobei der dritte ringförmige
Grad (17), eine Winkelausdehnung von ungefähr 270° hat und die Zähne (19) drei an
der Zahl und voneinander winklig im Wesentlichen um 120° beabstandet sind.
1. Élément de réduction de poids (1) pour l'industrie de la construction, constitué par
au moins un coffrage jetable (2), sensiblement en forme de pyramide tronquée, qui
est creux et a une surface supérieure fermée (4) et une ouverture inférieure (6a),
ledit élément de réduction de poids comprenant des pieds (8) d'une hauteur choisie,
chaque pied (8) ayant une extrémité inférieure (23) opposée à une extrémité supérieure
libre (12),
caractérisé en ce que :
dans lequel :
au moins à proximité des coins (7) du coffrage qui sont adjacents à ladite ouverture
inférieure (6a), ou
à proximité des coins (107) du coffrage (2) de ladite surface supérieure (4) et associés
audit coffrage,
on prévoit des moyens de mise en prise (10, 110),
moyennant quoi lesdits moyens de mise en prise (10, 110) sont stables et interconnectés
de manière sensiblement rotative, temporairement, avec des moyens de préhension (11)
associés à l'extrémité supérieure libre (12) desdits pieds (8), et dans lequel l'extrémité
inférieure (23) de chaque pied (8) est axialement décalée par rapport aux moyens de
préhension (11) et auxdits moyens de mise en prise temporaires (10, 110) respectivement.
2. Élément selon la revendication 1, dans lequel ledit coffrage jetable (2), à proximité
desdits coins (107) de ladite surface supérieure (4), est associé, de manière détachable,
auxdits moyens de mise en prise (110) pour l'interconnexion temporairement stable
avec lesdits moyens de préhension (11).
3. Élément selon la revendication 1, comprenant le coffrage jetable (2) intérieurement
creux prévu avec ladite surface supérieure (4), sensiblement plate, à partir de laquelle
des surfaces latérales de différentes formes (5) s'étendent et sont assemblées à la
pointe par une première crête périmétrale (6) qui définit ladite ouverture inférieure
(6a), moyennant quoi ledit coffrage jetable (2), au niveau des coins (7) du coffrage
qui sont adjacents à ladite ouverture inférieure et intérieurement par rapport à ladite
première crête périmétrale (6), sont associés de manière détachable audit pied (8),
d'une hauteur choisie, qui font saillie sur le côté opposé par rapport à ladite surface
supérieure (4).
4. Élément selon la revendication 1 ou 2, dans lequel au niveau desdits coins (7, 107)
du coffrage (2) qui sont adjacents à ladite ouverture inférieure (6a) ou lesdits coins
du coffrage de ladite surface supérieure (4), il y a des premiers trous (9) qui ont
une forme de plan polygonale régulière ou irrégulière ou sont circulaires, à proximité
desquels, on trouve lesdits moyens de mise en prise (10, 110), au niveau de chaque
extrémité supérieure libre (12), il y a un disque plat (13) avec une forme de plan
circulaire, qui vient en butée contre un fond formé de manière complémentaire (14)
qui entoure chacun desdits premiers trous (9).
5. Élément selon la revendication 4, dans lequel lesdits moyens de mise en prise (10,
110) sont constitués par une deuxième crête annulaire (15) qui entoure ledit trou
(9) et fait saillie vers le haut par rapport à ce dernier, est d'une hauteur choisie
et est agencée de manière concentrique et interne sur une languette cylindrique (16)
qui est prévue sur chacun desdits coins (7, 107) à proximité de ladite première crête
périmétrale (6) .
6. Élément selon la revendication 5, dans lequel lesdits moyens de préhension (11) sont
associés à une troisième crête annulaire (17) qui fait saillie axialement à la fois
par rapport audit premier trou (9) et par rapport audit disque plat (13), ladite troisième
crête annulaire (17) ayant un diamètre extérieur qui est inférieur au diamètre intérieur
de ladite deuxième crête annulaire (15) et une hauteur légèrement supérieure à cette
dernière, de sorte qu'une pointe (18) de ladite troisième crête annulaire (17) fait
saillie au-delà de la pointe correspondante de ladite deuxième crête annulaire (15).
7. Élément selon la revendication 6, dans lequel lesdits moyens de préhension (11) sont
associés à ladite pointe (18) et sont constitués par une ou plusieurs dents (19) qui
font saillie radialement et extérieurement par rapport à ladite troisième crête annulaire
(17) et interagissent en butée avec ladite deuxième crête annulaire (15) sous-jacente.
8. Élément selon la revendication 4, dans lequel chacun desdits pieds (8) a un corps
sensiblement conique (20) qui fait saillie au-dessous et de manière excentrique par
rapport audit disque plat (13), l'axe central (21) dudit disque plat (13), qui coïncide
avec l'axe dudit premier trou (9), étant distinct par rapport à l'axe central (22)
dudit corps (20), de sorte que ladite extrémité inférieure (23) dudit corps (20) est
axialement décalée par rapport auxdits moyens de préhension (11) et auxdits moyens
de mise en prise (10, 110).
9. Élément selon la revendication 6, dans lequel une fois que ladite troisième crête
annulaire (17) de chacun desdits pieds (8) est insérée dans ledit premier trou (9),
une rotation peut être communiquée audit pied (8) jusqu'à ce que ladite extrémité
inférieure (23) dudit corps (20) soit agencée au point choisi pour ne pas interférer
avec les bâtis de renforcement (3) agencés au-dessous dudit élément de réduction de
poids (1).
10. Élément selon la revendication 7, dans lequel des vides (24) de matériau sont prévus
sur ledit disque plat (13) au niveau de chacune desdits dents sur-jacentes (19), ladite
troisième crête annulaire (17) ayant une extension angulaire d'approximativement 270°
et lesdites dents (19) étant au nombre de trois et espacées mutuellement de manière
angulaire sensiblement de 120°.