ELEMENT DE COFFRAGE

FORMWORK ELEMENT

Abrégé français

L'invention concerne un élément de coffrage destiné à la construction de murs, de parois et analogues, consistant en un corps ou bloc prismatique rectangulaire (1'), creux, ouvert au niveau de sa base supérieure et inférieure, en mousse de polystyrène expansé ou analogue. L'élément de coffrage comprend une pluralité de petites protubérances prismatiques rectangulaires (3) sous forme de doigts, situées autour des bases et espacées par des cavités (4) dont la forme correspond à celle des protubérances, les protubérances de la base supérieure étant décalées par rapport à celles de la base inférieure. Lorsque l'on empile des corps de façon décalée dans la longueur, on obtient un accouplement langueté et bouveté offrant une stabilité optimale. En empilant une pluralité de corps (1'), on forme une chambre plane fermée par des faces interne et externe, pouvant recevoir une masse de béton armé qui constitue l'élément résistant du mur ou de la paroi et dont les armatures verticales traversent l'espace creux situé à l'intérieur des corps (1') et les armatures horizontales traversent des évidements (6) situés dans les parois latérales plus petites (5) des corps.

Abrégé anglais

The invention relates to a formwork element which is specially designed for
the construction of walls and similar. The inventive element comprises a
hollow rectangular prismatic block or body (1') which is open at the lower and
upper faces thereof and which is made from expanded polystyrene foam or
another similar material. The edges of the aforementioned faces are provided
with numerous small rectangular prismatic projections (3) in the form of cubes
which define therebetween similarly-configured housings (4), the projections
on the upper face being offset in relation to those on the lower face. In this
way, when the bodies are stacked such that they are offset lengthways, a
tongue-and-groove connection is created therebetween, ensuring optimum
stability. Numerous bodies (1') can be stacked to produce a level chamber
which is closed at the inner and outer faces thereof and which can receive a
mass of reinforced concrete forming the resistant element of the wall.
According to the invention, the vertical reinforcements pass through the inner
hollow space of the bodies (1') while the horizontal reinforcements pass
through openings (6) in the smaller lateral walls (5) thereof.

Revendications

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CLAIMS
1. Formwork element which, being especially designed for the obtention of
reinforced concrete walls, is characterised in that it has a rectangular-
prismatic
(1) body, made of hollow, expanded polystyrene foam or other similar material,
open at the upper and lower faces, provided with multiple small projections
(3)
on the periphery of said faces which have the form of die and a staggered
distribution and which define equally formed housings (4) between one another,
the projections on the upper face being offset with respect to those of the
lower
face, in order to achieve a multiple tongue-and-groove coupling upon
superimposition of the bodies (1).
2. Formwork element, according to claim 1, characterised in that said
prismatic
body (1) has internal rigidifying partitions (2), preferably of a height
substantially
smaller than that of the body itself (1).
3. Formwork element, according to the preceding claims, characterised in that
the prismatic body (1') incorporates wide indentations (6) on the edges of its
smaller side walls (5), when said body (1') is designed to become a part of
rows
on the wall whereon it is necessary to create horizontal metal frameworks.
4. Formwork element, according to claim 3, characterised in that the prismatic
bodies (1") designed to occupy the end positions on said rows which receive
the horizontal metal frameworks, exhibit indentations (6) on only one of the
smaller side walls, while the other, the terminal one, is closed.
5. Formwork element, according to the preceding claims, characterised by the
fact that it constitutes a lost element, designed to indefinitely become a
part of
the corresponding wall, to which it confers the thermal and acoustic
insulation
characteristics derived from its own nature.
6. Formwork element, according to the preceding claims, characterised by the
fact that it is capable of housing therein, in addition to the said vertical
and
horizontal frameworks, pipes and conduits for auxiliary services such as
water,
electricity, or other, which are laterally accessible by cutting the
corresponding
prismatic body's wall.

Description

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FORMWORK ELEMENT
DESCRIPTION
PURPOSE OF THE INVENTION
This invention refers to a formwork element which is especially designed for
the
construction of both interior and exterior walls, and for both one-storey and
multi-storey buildings.
Said element allows an easy and fast assembly, which can be cut in order to
adequate its dimensions to certain practical requirements.
The formwork element is designed for the obtention of concrete walls,
appropriately reinforced, wherein the pipes or ducts for various services are
embedded, with the special feature that said element gives to the walls a high
insulation coefficient, both thermal and acoustic.
The formwork element is useful for industrial buildings, houses, condominiums,
garages, swimming pools, cold chambers, etc.
BACKGROUND OF THE INVENTION
As is well-known, within the wide range of possibilities that present-day
technology offers for the construction of walls, one solution consists of
making
said walls with reinforced concrete, pouring the concrete "in situ", after
shaping
the appropriate formwork.
In general, these formworks consist of metal plates, appropriately rigidified,
which are interconnected forming two parallel vertical planes, appropriately
connected by means of spacers, in such a way that once the formwork has
been duly configured, the required metal frameworks are introduced therein and
it is finally concreted.
This solution makes it possible the obtention of walls with a high solidity,
which

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nevertheless exhibit various problems. In this regard:
- In order for the building or construction in question to be solidly
finished, its various walls must be linked together by means of said
metal frameworks and the concrete must be poured only once, which
requires the use of a large formwork surface, i.e. a large number of
reinforced metal plates, which entails considerable investment costs
and the handling of large amounts of very heavy material.
- In most cases the formwork plates, which have a modular structure,
are not suited to the required practical measures, so that the
formwork must be completed either by means of custom-made
plates, with the ensuing cost increase, or else by means of fortuitous
lower-cost solutions, such as, for example, custom-cut wood planks,
which adversely affect the structural resistance of the entire
formwork, as well as the construction's aesthetic finishing.
- Even though these formworks make it possible to incorporate all
types of ducts and pipes, such as, for example, wastewater drainage
ducts, sanitary water pipes, electric conduits, etc., significant
problems arise in connecting these conduits with the exterior, since
the formworks' high cost does not make it possible to create orifices
therein in order to access said conduits.
- Even though the obtained wall offers high mechanic resistance, it has
a very low insulation coefficient, both from the thermal point of view
and the acoustic point of view.
DESCRIPTION OF THE INVENTION
The formwork element proposed by the invention resolves in a fully
satisfactory
manner the aforementioned problems, since it constitutes a lost element
designed to definitively form part of the wall obtained thereby, and, due to
its
own nature, it incorporates its thermal and acoustic insulation
characteristics to
said wail. Moreover, it is easily frangible or capable of being cut in order
to suit
its dimensions to the practical requirements of each case and to create
orifices
or windows therein in order to access the interior ducts.
To this end, and more specifically, said formwork element is materialised in a

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body that is essentially rectangular-prismatic, made of expanded polystyrene
foam or other material with similar characteristics. It is a hollow body that
is
open at its facesand provided with internal rigidifying partitions, with the
special
feature that said body incorporates a plurality of small projections, also
rectangular-prismatic, on the periphery of said faces, with a staggered
distribution, which define equally-configured housings between one another, so
that the projections or cubes on the upper face are opposite the housings on
the lower face, which makes it possible to achieve a high solid tongue-and-
groove connection between them upon superimposition of the bodies.
These rectangular-prismatic elements or bodies exhibit a length that is
significantly greater than the height and width, so that walls may be
constructed
in rows, in a manner similar to conventional construction blocks or bricks,
the
bodies in each row remaining longitudinally offset with respect to the rows
located immediately above and below, so that, in turn, these bodies maintain a
staggered distribution on the wall which ensures a perfect relative stability
for all
of them, and which, moreover, allows for "keying" between the walls on the
corners or "T" connections.
In any case, the union of the appropriate number of formwork elements, in a co-
planar arrangement, and according to the specific requirements of each case,
entails obtaining two parallel formwork surfaces, which are perfectly enclosed
and continuous, and between which an interior concrete-receiving housing is
created, which may be poured therein by any conventional method and which
ensures that the mass of concrete extends in one piece to the entire wall or
walls of the concerned building or construction, where it is also possible,
moreover, to introduce vertical metal frameworks therein which jointly emerge
from the foundations.
When horizontal frameworks are also needed, the blocks in certain alignments
will be provided with wide indentations on the smaller side walls through
which
said frameworks will pass.
The nature of the material comprising these formwork elements, which, as
already mentioned, is expanded polystyrene foam, incorporates its thermal and
acoustic insulation characteristics to the enclosure, as well as being easy to
cut,
using a simple saw or any other appropriate tool, both for the production of

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finish parts or elements with non-standard dimensions and for the creation of
orifices or windows on the larger walls for the passage of, or access to,
ducts
and pipes, if necessary. To this end, these elements incorporate grooves or
marks on the side walls which facilitate the cutting.
DESCRIPTION OF THE DRAWINGS
In order to complement the description being made and to contribute to a
better
understanding of the characteristics of the invention, according to a
preferred
example of practical embodiment thereof, we attach, as integral part of said
description, a set of drawings which, with an illustrative and non-limiting
character, represent the following:
Figure 1.- It shows, according to a schematic perspective representation, a
formwork element made in accordance with the object of this invention.
Figure 2.- !t shows, by means of a representation similar to that of figure 1,
another formwork element especially designed to allow implementation of
horizontal metal frameworks on the wall that is to be produced.
Figure 3.- It shows, by means of a representation similar to the preceding
figures, another formwork element with openings on one of its ends only, which
may be used as a closure element where the horizontal framework ends.
Figure 4.- It shows, also by means of a perspective view, a partial detail of
a
wall made with formwork elements according to the invention, in a phase prior
to the concreting phase.
Figure 5.- It shows, finally, a longitudinal section detail of an entirely
finished
wall.
Figure 6.- It shows another detail of the same wall, in this case in cross-
section.
PREFERRED EMBODIMENT OF THE INVENTION
In view of the above-mentioned figures, one can see how the formwork element
proposed by the invention is constituted by a rectangular prismatic body (1),
for

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instance, with external dimensions similar to those of a classic construction
block, but with the special feature that it is entirely made of hollow,
expanded
polystyrene foam, open at both the upper and lower faces, and preferably
provided with rigidifying interior and transverse partitions (2), whose height
is
significantly lower than that of the body itself (1).
These elements may be interconnected by tonguing-and-grooving, as shown in
figure 2, for which purpose, on the perimeter of the upper and lower faces,
and
as an extension of the considerably thick perimeter wall, they exhibit a
plurality
of small rectangular-prismatic projections (3) in the form of die, which have
a
staggered distribution and which create housings (4) between one another,
which formally and dimensionally coincide with the housings, but there is an
offset between the upper and lower faces, so that, when the bodies (1 ) are
stacked, the projections or die (3) of one remain opposite and finally
embedded
in the other's housings (4), in order to achieve the desired tongue-and-groove
effect, which offers high solidity in the co-planar fixing between blocks.
The block may exhibit four side walls of the same height, as shown in figure
1,
or else the smaller lateral walls (5) may be affected by wide indentations
(6), as
is the case with block {1') shown in figure 2, so that, while in the first
case it is
only possible to provide vertical metal frameworks, which pass through the
modules or elements (1) interior cavities, in the second case, horizontal
frameworks may also be provided, specifically located on the indentations (6).
These indentations (6) define longitudinal grooves on the wall for each row
obtained by means of bodies (1') of this type, which naturally must be closed
at
the end, for which this purpose, the existence of bodies (1 ") such as the one
shown in figure 3 has been anticipated, with indentations (6) on only one of
the
smaller side walls (5), while the other one acts as a closure element,
exhibiting
a height that coincides with that of the larger side walls.
In any case, after the coupling between bodies or modules (1 ), (1'), (1 "),
and as
shown in figures 4, 5, and 6, the larger walls of the bodies (1 ) create an
integral
enclosure which corresponds to the internal and external faces of the wall,
forming a continuous chamber, closed at the lower end by the floor (7), which
is
undeformable through the smaller side walls (5) and the interior rigidifying
partitions (2) of the prismatic bodies (1), (1'), (1"), a chamber which will

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subsequently be filled with a mass of concrete (8), which, together with the
metal frameworks, grants the wall the appropriate structural rigidity, said
mass
of concrete (8), however, remaining completely insulated from both the
exterior
and the interior of the wall, so that, despite its high degree of
conductivity, it
does not act as a thermal bridge, the larger side walls of the various bodies
or
modules (1 ), (1'), (1 ") defining, respectively, an internal and external
barrier to
both thermal and acoustic transmission.
Prior to the pouring of the concrete in the hollow chamber of the formwork,
ducts may be provided therein, such as the downpipe (9) shown in figure 4,
electric conduits (10), etc., with side accesses (11) and (12) towards the
internal or the external face of the wall, which are easily implemented on the
formwork due to its own nature, since the expanded polystyrene foam may be
easily cut with a saw or any appropriate cutting tool.
The wall wilt be completed with any exterior (13) or interior (14) coating,
made
of any adequate material, in order to provide it with any finishing, such as,
for
instance, face bricks, plaster, tiles, boarding, wallpaper, etc.

Dessin représentatif