FR3088843A1 - DEVICE FOR PRODUCING A CONCRETE FRAMEWORK WITH MONO OR MULTIPLE OFFSET ON THE THICKNESS AND METHOD FOR PRODUCING SUCH A STRUCTURE - Google Patents

Abstract

The invention relates to a device and associated method for producing an openwork concrete structure with single or multiple offset over the thickness "3D mesh", (50) comprising a rigid mold block (10) of machined polymer which comprises at least one molding plate (10a), said molding plate comprising reservations (12) respectively having a draft less than 10 degrees, all or part of the reservations (12) having, on the upper surface, an additional thickness (15). Figure to be published with the abstract: Fig. 1

Description

Description

Title of the invention: DEVICE FOR REALIZATION

OF AN ADJUSTED CONCRETE STRUCTURE WITH A MONO OR MULTIPLE OFFSET ON THE THICKNESS AND METHOD FOR THE PRODUCTION OF SUCH A STRUCTURE Technical field [0001] The invention relates to a device for producing an openwork concrete structure and a method for the realization of such a structure.

Prior art [0002] Openwork concrete structures, also known as concrete mesh terminology, are structures mainly intended for the production of facade claddings or building elements. They are chosen mainly for their aesthetic qualities. As an example, it can be mentioned the Museum of Civilizations of Europe and the Mediterranean "MuCEM", some parts of the building were made with this type of structure. Concrete nets are conventionally manufactured with ultra high performance concretes which give the structure thus produced properties of high durability and high mechanical performance.

From a dimensional point of view, concrete grids are conventionally more or less perforated planar elements. The openings are made by means of reservations made in a mold base. Given the adhesion properties of the concrete to the molding support, provision is made, in order to facilitate the demolding of the concrete resins, or alternatively removable reservations so as to allow their dismantling before the part demolding operation or else solid reservations of the mold but with, in this case, a skin (or fruit) greater than 5 degrees (in general of the order of 10 degrees), or removable reservations with bodies.

The spoils, if they have the advantage of facilitating demolding, impact the aesthetic aspect of the structure obtained. They can also make it more difficult to maintain the mold, which can become dirty and subsequently impact the aesthetic quality of the finished structure.

Current equipment and methods do not allow the design of concrete nets with little or no draft at the level of reservations for rigid molds.

Likewise, the removal of the removable reservations may remain easy and it may happen that the molded structure is subjected to shocks or stresses which can generate zones of weakness and thus locally alter the strength of the structure.

Concrete, moreover, is a material which exhibits potentially significant shrinkage deformations at a young age, in particular as a function of the volume of paste present in the mixture. The deformations prevented during the drying operation due to the presence of the reservations can lead to risks of cracking at the periphery of the reservations.

The molds currently used to make the concrete nets are steel, wooden, silicone, polyurethane or a mixture of these materials to allow the design of the different parts of the mold. However, such molds have the major disadvantage of being either expensive or of having a limited lifespan. They also do not make it possible to produce structures having a relief in the plane of the thickness of said structure.

The invention aims to remedy these problems by proposing a device and an associated method for producing a perforated concrete structure (mesh) resistant and durable whose aesthetic quality has been controlled so as to provide a structure suitable for aesthetic criteria expected depending on the type of application for which the structure is intended.

The device and the associated method according to the invention also aims to produce an openwork concrete structure having a relief in the plane of the thickness of the structure.

OBJECT OF THE INVENTION For this purpose, and according to a first aspect, the invention proposes a device for producing an openwork concrete structure with mono or multiple offset over the thickness comprising a rigid polymer mold block machined which comprises at least one molding plate, said molding plate comprising reservations having respectively a draft less than 10 degrees, all or part of the reservations having, on the upper surface, an additional thickness.

This extra thickness formed on the surface of the reservations is advantageously between 3 millimeters and 7 millimeters. Preferably, the additional thickness is of the order of 5 millimeters.

According to a particular alternative embodiment, the mold block comprises two molding plates arranged to define, when they are positioned in contact with one another along a vertical joint plane, a closed lower end and an opening for pouring concrete between said molding plates.

Advantageously, the bodies are less than 5 degrees, and preferably are of the order of 3 degrees.

Advantageously, the mold block is formed of layers preferably of polyolefin. According to a particular embodiment, the layers are made of high density polyethylene whose molecular weight is between 250,000 g / mol and 1,200,000 g / mol, and preferably 500,000 g / mol.

It can be expected that the layers of the mold block are fixed together by means of screws. In this case, it may advantageously be that the heads of all or some of the screws constitute the extra thicknesses formed on the upper surface of the reservations.

Advantageously, the mold block includes removable formwork cheeks or formed integrally with the molding plate.

Advantageously, the molding plate is secured to a rigid support consisting of at least one plywood plate or of the same nature as the mold block.

Advantageously, the device comprises means for generating agitation within the mold block.

Advantageously, the device comprises means for reversing the support. The invention also relates to a method for producing an openwork concrete structure by means of a device as described above.

The method is remarkable in that it comprises, according to an alternative embodiment, a flat casting operation (or horizontal casting) of a concrete in the fresh state on the molding plate and a demolding operation after the concrete has hardened by inverting the mold block on a mold release support.

According to another alternative embodiment, the casting operation consists of a vertical casting operation or in an inclined plane of the concrete in the fresh state in the mold block which comprises two pouring plates joined one to the other. another according to a vertical joint plane, through the opening made at the level of the molding plates.

Advantageously, the mold block is subjected to actions generating agitation within it during the casting operation and / or during the demolding operation.

The invention also relates to any openwork concrete structure with single or multiple offset over the thickness obtained according to the method described above.

The invention relates, according to a particular application, an openwork concrete body guard obtained according to one of the methods (flat casting or vertical casting) described above. It is of course obvious that the invention is not limited to this application and that perforated structures can be produced for the purposes of other applications. By way of example, let us cite the production of facade claddings, wall cladding, sun shades, pool surrounds, stairwells, sliding gates, fences, bus shelters and furniture. of interiors and exteriors.

Brief Description of the Drawings Other characteristics and advantages of the invention will emerge from the detailed description of the invention which will follow with reference to the appended figures and in which:

[Fig.l]

FIG. 1 represents a perspective view of a part of a device for producing a perforated concrete structure by flat casting according to an exemplary embodiment;

[Fig.2]

Figure 2 shows a front view of the mold of Figure 1;

[Fig.3]

Figure 3 shows a sectional view along the axis AA of the mold of Figure 2;

[Fig.4]

Figure 4 shows a detail view of the mold of Figure 3;

[Fig.5]

FIG. 5 represents a view of the openwork concrete structure obtained with the mold of FIG. L For the sake of clarity, the identical or similar elements of the various embodiments are identified by identical reference signs on the whole figures.

Description of the embodiments

Description of an example of a device In the following, a device is described for producing an openwork concrete structure 50 by flat casting as illustrated in FIG. 5. FIGS. 1 to 4 illustrate part of the device, namely a mold 1.

The illustrated mold 1 comprises a rigid mold block 10 machined comprising a horizontal molding plate 10a. This is made of a polymer material whose properties meet the following requirements: suitability for milling, poor adhesion to concrete, scratch-free surface condition during the manufacture of the mold, resistance to alkalis, ease of cleaning (low fouling ), number of important uses (more than 1000 operations), resistance to high temperatures, sufficient rigidity allowing the part to be removed from the mold.

The polymer material chosen can advantageously be a material from the family of polyolefins in the form of layers. These layers can be layers of high density polyethylene (HDPE) whose molecular weight is between 250,000 and 1,200,000 g / mol and more specifically 500,000 g / mol. When the molding plate 10a is formed from a plurality of such layers, the latter are advantageously fixed to one another by means of screws, the heads of which may, if necessary, constitute the extra thicknesses described below.

The molding plate 10a includes reservations 12 arranged to define the openings 13 desired in the structure (Figure 5). The mold block being machined, the reservations are formed integrally with the molding plate 10a.

In the illustrated embodiment, the molding plate 10a has reservations having multiple heights, in this case four heights (hl, h2, h3, h4) (visible in Figure 3). Given these different heights of the reservations, the structure obtained will include variations (four) in its thickness. This is of course an example of an embodiment, the molding plate possibly having a different number of reservation heights including reservations of one and the same height. The structure thus obtained will be qualified as a mono or multiple offset structure over the thickness, “mono” offset being understood by a structure having no variation in its thickness.

In this embodiment, the demolding of the structure once the hardened concrete is produced by inverting the mold block 10. To allow demolding, the reservations 12 advantageously have spoils. However, these will be relatively low compared to those provided for in the devices of the prior art, given the adjustments made. They are thus advantageously less than 5 degrees, and preferably of the order of 3 degrees.

In the embodiment described, all or part of the reservations 12 have, on the upper surface, an additional thickness 15. In the illustrated embodiment, this additional thickness 15 is created by heads 15a of screws 2 fixing the molding plate 10a to a support 20. This additional thickness 15 formed on the surface 12a of the reservations 12 is between 3 millimeters and 7 millimeters, and is preferably of the order of 5 millimeters. Generally, the additional thickness will preferably be equal to the thickness of the structure to be produced.

According to an advantageous embodiment, the mold block 10 comprises formwork cheeks 11. The latter can either be formed integrally with said mold block 10, or removable. The advantage of this last configuration is that it makes it possible to produce a mesh which can be embedded in the fixing sole.

The format of the molding plate 10a is preferably between 2000 and 3000 mm for the length, 1000 to 1500 mm for the width, with a thickness of 20 to 80 mm.

In the illustrated embodiment, the molding plate 10a constituting the mold block 10 is secured to a rigid support 20 consisting of two support plates 21, 22. The external support plate 22 (plate furthest from the plate molding 10a has the function on the one hand to improve the rigidity of the mold block 10 and on the other hand to allow the attachment of turning straps 3 on the support plate 21 for the safe turning of the mold block 10 for the purposes of demoulding of the concrete part. The support plates 21, 22 can be plywood or of the same kind as the mold block 10, namely of polymer. According to an advantageous embodiment, the internal plate 21 (support plate in contact with the plate molding 10a is made of plywood or polymer, while the outer plate 22 is made of plywood. Unlike a metal mold, this solution has the advantage of being achievable on demand according to the expectations of the end user, little c costly, easily replaceable and requires little handling. It is of course obvious that the invention is not limited to this configuration, and that it can be provided that the support consists of a single support plate, or more than two support plates. Likewise, provision may be made for the mold block 10 to be formed integrally with the support 20.

As previously indicated, the molding block 10 is fixed to the support 20 by means of screws 2, the screw heads 15a of which protrude from the upper surface of the reservations so as to create an additional thickness 15 of material relative to the surface. upper of the reservations 12. The screws 2 are advantageously arranged on the periphery of the mold block 10 / support 20 assembly, other screws can also be provided on internal reservations 12.

In order to favor the filling of the molding plate 10a during the pouring of the concrete and the demolding of the part once the concrete has hardened, as well as to improve the distribution of the concrete on the molding plate 10a, the device comprises means for generating agitation within the mold block 10 (not shown). It can be means generating vibrations such as for example vibrators, shocks such as for example hitting or preferably horizontal agitation such as for example rollers or balls.

Mold production method The mold block 10 is produced from a design of the mesh to be produced, being specified the maximum height of the stiffeners and the different thicknesses of the disbursed, redrawn in 3D with the integration of all technical specifications (fruit, leaves, etc.).

Preferably, the mold block 10 will be produced to obtain structures of length between 2000 and 3000 mm, of width between 1000 to 1500 mm and of a thickness of between 20 and 80 mm. The mold block 10 is of course not limited to the production of structures according to such dimensions. It can in particular be provided for making structures of smaller dimensions, in particular for making them portable, the latter then being able to be, if necessary, assembled on site. This does not of course also exclude the production of mold block 10 according to dimensions greater than those mentioned above.

Method of producing an openwork structure using the device described above [0049] The openwork concrete structure 50 is produced with the coming device described as follows.

The molding plate 10a is filled: the fresh concrete is poured flat on the molding plate 10a arranged horizontally, over a given height of the reservations 12, according to the desired thickness of the structure to be obtained. The filling of the molding plate 10a is advantageously done in at least two passes, with potentially a supply of energy in order to reduce the shear threshold of the material in the fresh state and to facilitate its flow in the mold block 10 This energy supply can be made using stirring means as described above.

After the concrete has hardened, the concrete structure is removed from the mold (formwork). Demoulding is done by inverting the mold (mold block 10 and support 20) on a flat release support (preferably plywood board).

Thanks to the useful space created between the mold block 10 and the mold release support by the heads 15a of screw 2, as well as the undercuts and the rigidity of the mold, the concrete part is removed from the mold block 10 by sliding. In order to allow the concrete structure to slide uniformly and to avoid damaging it, agitation can be applied to the exterior surface of the mold support via the agitation means.

In order to facilitate the demolding of the concrete part, provision may also be made to apply a demolding agent to the molding plate 10a before the latter is filled.

In the embodiment described, the extra thicknesses 15 are formed on the upper surface of the molding plate 10a are formed by the screw heads. This is of course an exemplary embodiment, any other means or technique generating an extra thickness on the surface of the plate falling within the scope of the invention. For example, it may be an excess thickness of material from the molding plate 10a.

In the embodiment just described, the mold block 10 includes a horizontal molding plate. The casting is carried out flat. The invention is not, however, limited to the flat pouring of concrete. It can also be carried out vertically. In this case, the mold block 10 comprises two molding plates arranged to define, when they are positioned in contact with one another along a vertical joint plane, a closed lower end and an opening for pouring the concrete. between said molding plates. Preferably, the opening will be made at the upper end when the two molding plates are positioned in contact with one another. It is of course obvious that the opening can also be arranged at one of the lateral edges of the mold block 10 formed. It can also be provided that the mold block 10 has several openings for pouring the concrete in order to facilitate and optimize the time for pouring the concrete between the two plates. It can also be provided to pour the concrete in an inclined plane, in particular during the casting phase, in order to promote a preferential orientation of fibers.

Advantageously, the two molding plates are equipped with pins or the like which make it possible to ensure perfect continuity of the faces at the junction of the two molds. The two mold plates are assembled together by bolting, for example by means of a centering screw. This allows the hydrostatic thrust applied to the walls of the molding plates to be taken up during the concreting operation.

The formwork of the structure obtained once the concrete is hardened is produced by placing the mold flat, the lower plate preferably being fixed on a support. The bolts are then disassembled and the upper molding plate removed by lifting or using extraction screws. The part (concrete + lower molding plate) is then turned 180 ° to be placed on a mold release support as for the formwork removal operation than that carried out in the context of a flat casting.

It is also possible to carry out formwork in a vertical position. To do this, the mold must be turned over to arrange the structure so that the latter rests on a foot which is then blocked for example by means of a pin. The assembly bolts of the two plates between them are then dismantled, the two plates then being separated from one another using extraction screws.

Application of the perforated structures obtained Among the applications envisaged, mention may be made of the use of the perforated structures obtained using the device described above in particular, but not exclusively, as cladding for the facade, for facing wall, bodyguard, solar shading, pool surround, stairwell, sliding gate, fencing, surrounding bus shelters, parking payment terminals, staircase for descent pool and indoor and outdoor furniture.

The system for fixing the structure will be potentially different depending on the use and the destination thereof. The fastening system is advantageously designed to withstand the environmental conditions of the environment in which it is located and to participate in the recovery and transmission of the forces applied to the mesh. It can be expected that the fixing system advantageously comprises a visco-elastic material allowing shock absorption in a direction perpendicular to the mesh. It can also be provided that the fastening system is sculpted so as to fit into the body of the structure.

In the embodiments previously described, the mold 1 is formed of separate elements: a molding plate and a support. According to an alternative embodiment, provision may be made for the mold to be a one-piece polyolefin mold. According to this alternative embodiment, the fixing straps and the stirring means would be directly integrated into the one-piece mold.

The invention is described in the foregoing by way of example. It is understood that a person skilled in the art is able to carry out different variant embodiments of the invention without departing from the scope of the invention as defined by the claims.

Claims (1)

Claims [Claim 1] Device for producing an openwork concrete structure with single or multiple offset over the thickness (50) comprising a rigid mold block (10) of machined polymer which comprises at least one molding plate (10a), said molding plate comprising reservations (12) respectively having a draft less than 10 degrees, all or part of the reservations (12) having, on the upper surface, an extra thickness (15). [Claim 2] Device according to claim 1, characterized in that the additional thickness (15) formed on the surface of the reservations (12) is between 3 millimeters and 7 millimeters, and is preferably of the order of 5 millimeters. [Claim 3] Device according to claim 1 or claim 2, characterized in that the mold block (10) comprises two molding plates arranged to define, when they are positioned in contact with one another along a vertical joint plane, a closed lower end and an opening for pouring the concrete between said molding plates. [Claim 4] Device according to any one of the preceding claims, characterized in that the bodies are less than 5 degrees, and preferably are of the order of 3 degrees. [Claim 5] Device according to any one of the preceding claims, characterized in that the mold block (10) is formed of layers preferably of polyolefin. [Claim 6] Device according to the preceding claim, characterized in that the layers are layers of high density polyethylene whose molecular weight is between 250,000 and 1,200,000 g / mol, and preferably 500,000 g / mol. [Claim 7] Device according to claim 5 or claim 6, characterized in that the layers of the mold block (10) are fixed to each other by means of screws the heads of which constitute the extra thicknesses (15) formed on the upper surface of the reservations (12). [Claim 8] Device according to any one of the preceding claims, characterized in that the mold block (10) has removable formwork cheeks or formed integrally with the molding plate (10a). [Claim 9] Device according to any one of the preceding claims, characterized in that the molding plate (10a) is integral with a rigid support consisting of at least one plywood plate or similarly nature as said molding plate (10a). [Claim 10] Device according to any one of the preceding claims, characterized in that it includes means for generating agitation within the mold block (10). [Claim 11] Device according to any one of the preceding claims, characterized in that it includes means for reversing the support. [Claim 12] Method for producing an openwork concrete structure (50) by means of a device according to any one of Claims 1 and 2 and 4 to 12, characterized in that it comprises a flat casting operation of a concrete in the fresh state on the molding plate (10a) and a demolding operation after hardening of the concrete by inversion of the mold block (10) on a demolding support. [Claim 13] Method by means of a device according to any one of Claims 1 to 12, characterized in that it comprises a vertical casting operation or in an inclined plane of a concrete in the fresh state in the mold block (10 ) comprising two pouring plates joined to one another along a vertical joint plane, through the opening made at the level of the molding plates. [Claim 14] A method according to claim 12 or claim 13, characterized in that the mold block (10) is subjected to actions generating agitation within it during the casting operation and / or during the demolding operation. [Claim 15] Openwork concrete structure with mono or multiple offset over the thickness (50) obtained according to the method according to any one of claims 12 to 14. [Claim 16] Bodywork in openwork concrete obtained according to the process according to any one of Claims 13 to 15. 1/3