WO2009092977A2

WO2009092977A2 - Method for making and decorating concrete structures

Info

Publication number: WO2009092977A2
Application number: PCT/FR2009/050067
Authority: WO
Inventors: Milène Guermont
Original assignee: Guermont Milene
Priority date: 2008-01-24
Filing date: 2009-01-19
Publication date: 2009-07-30
Also published as: EP2382070A2; FR2980192A1; WO2009092977A3; FR2980192B1; FR2926742B1; FR2926742A1

Abstract

The invention relates to a method for making a concrete structure, that comprises the following steps: pouring concrete into a mould, in particular concrete of the ultra-high performance type (BUHP) or of the fibered ultra-high performance type (BFUHP); restraining the discharge of air bubbles at the upper surface of the concrete in order to make bumps visible during the concrete curing; vibrating the mould in order to at least partially discharge the air bubbles contained in the concrete.

Description

The present invention relates to various methods of manufacturing and decorating concrete structures.

The term "concrete" refers to a material made from aggregates, for example sand and / or chippings, agglomerated with a binder.

The binder can for example be "cement", that is to say, taken by hydration, thereby obtaining a concrete cement.

The mechanical compressive strength of concrete varies depending on the nature of the concrete itself, for example depending on the amount of water contained in the concrete.

The orders of magnitude conventionally obtained on cylindrical specimens 16 * 32 mm, are of the order of:

25 to 35 MPa, or even 50 MPa, for concrete type BFC (concreting manufactured on site), - from 40 to 60 MPa for a concrete type BPE (Ready-to-Use Concrete), up to 200 MPa for a concrete concrete type BHT (High Performance Concrete), about 500 MPa for a concrete type BUHP (Ultra High Performance Concrete).

Ultra High Performance type concretes (BUHP) and Ultra High Performance Fiber (BFUHP) type concretes are preferred for implementing the present invention.

In all of the following aspects, the concrete structure may be a structure, a partition, a post, a constituent part of a residential building or office building, a piece of furniture, a floor covering, a cladding, Wall,...

Creation of asperities

According to a first of its aspects, the subject of the invention is a method for manufacturing a concrete structure, comprising the following steps:

pouring concrete into a mold, especially ultra-high performance type concrete (BUHP) or Ultra High Performance Fiber (BFUHP) type,

counteracting the evacuation of the air bubbles at the upper surface of the concrete, so as to reveal asperities during the setting of the concrete, - To vibrate the mold so as to evacuate at least partially the air bubbles contained in the concrete.

The evacuation of the air bubbles is for example counteracted by a solid part, for example a plate, for example glass or wood, which can be attached to the mold, for example, and which has for example a horizontal surface in contact with concrete.

The area of the solid part may be greater than or equal to 1 cm ² , more preferably 1 dm ² , even better 10 dm ² , or even 50 dm ² , or even more.

According to this aspect of the invention, it is possible to create asperities having the appearance of "craters" on at least a portion of an apparent face of the concrete structure.

Craters have, for example, for at least some, a diameter greater than or equal to 1 mm, or even 2 mm, or even 5 mm or 10 mm and a depth greater than or equal to 0.5 mm, or even 2 mm or 5 mm or 10 mm , see more.

The number of craters having such dimensions is for example greater than or equal to 1 by dm ² , better still or equal to 2.5, or even 10, 20 or 50.

The solid part can only partially cover the upper surface of the concrete, which can create a contrast effect between two regions of the upper surface of the concrete, one smooth and the other with asperities created.

Advantageously, the solid part is in direct contact with the concrete, so that the evacuation of air bubbles is the most upset possible.

The vibration of the mold can for example be done through a vibrating support on which the mold is placed.

The craters obtained can optionally be filled, at least partially, with a resin, for example a colorless or colored transparent resin, or with a concrete of another color for example, in order to provide an additional aesthetic effect.

It is also possible to apply a protective product, for example a varnish or a paint, on the surface of the concrete, this protective product can marry the relief of the craters without filling them. The method may also include the step of injecting air into the concrete, before and / or after casting of the concrete, to enhance the formation of air bubbles and increase the likelihood of crater formation under the solid part and / or increase the density or size of the craters. The injected air is, for example, compressed air.

The injection of air is preferably carried out before fixing the solid part which hinders the evacuation of the bubbles and before the vibration is started at all.

Alternatively, the method may further include the step of placing a material in contact with the concrete prior to setting. This material may be placed, in an exemplary implementation of the invention, randomly on one or more areas of the bottom of the mold, or the solid part, or on the surface of the concrete before the introduction of the solid part. . It is for example a mineral or vegetable material, for example salt, sugar, algae, sand, among others, in order to obtain particular effects related to the nature of the material used, or to an adhesive, a fabric or a sheet of paper, among others.

At least a portion of the surface of the crater-forming structure is intended to be exposed to the view, at least partially, during the use of the structure, after demolding and possibly assembly with other elements. Optical fibers can be deposited in the mold before pouring the concrete.

The manufacturing process can be used for the manufacture of concrete structures, partitions, buildings, including homes or offices, furniture, for example a tabletop or countertop. The structure can be in particular a piece of furniture, including a table or a chair, a floor covering, a building element.

FIGS. 1A-1C of the attached drawing illustrate steps of an exemplary method according to this first aspect of the invention, allowing the creation of asperities in the form of "craters" on at least a portion of the surface of the invention. a concrete structure. In order to obtain the finest possible surface condition, concrete of the BFUHP (Ultra High Performance Fiber Concrete) type having a particle size preferably of less than 500 microns can be used.

The various components of the concrete are firstly mixed in a first stage, namely for example: "premix" (mixture of cement, sand, silica and fired silica, that is to say crushed limestone), water, fluidizer, accelerator, fibers and possibly pigments. It is possible to inject air into this mixture, for example with an air gun, to enhance the formation of air bubbles in the concrete. As a result, the probability of forming the asperities is increased.

The concrete 20 in the fluid state is then cast, as illustrated in FIG. 1A, in a mold 21 (also called formwork), this mold 21 being of any shape and comprising for example a frame 22 and a bottom 23, the filling is preferably performed up to the edge of the frame 22.

Then, as illustrated in FIG. 1B, a plate 24, for example a wooden board, on which a release agent or oil has optionally been sprayed, is affixed to the upper surface of the concrete 20 where it is desired to make appear asperities.

This plate 24 is preferably fixed to the frame 22 so that the concrete 20 is in perfect contact with the plate 24. For example, the plate 24 can be fastened with nails 25 to the frame 22, as illustrated in FIG. . The assembly consisting of the mold 21, the concrete 20 and the plate 24 is then vibrated on a vibrating table 27 for a period of between for example 1 and 15 minutes. As a result, the air contained in the concrete 20 rises to its surface.

When the de-bubbling is completed, the assembly formed by the mold 21, the concrete 20 and the plate 24 is allowed to rest for the time necessary for setting the concrete, then the plate 24 is removed.

Once unmolded, it is then possible to refine the visual appearance of the concrete structure thus obtained.

A first alternative embodiment of the method consists in depositing a selected material on a surface of the mold 21 before pouring the concrete 20, on the plate 24 or on the concrete before placing the plate 24, this material being able for example to be salt to create crystals, sugar that can crystallize, seaweed that can expand on contact with fresh concrete to generate marine odors or silt, sand, adhesive, fabric or leaf, to obtain a surface appearance specific to this material. The plate 24 may be rigid or flexible, and may possibly not be reported on the mold but be present from the start on it. The plate 24 may be flat or not, depending on the shape to be given to the structure. After demolding, the surface covered by the plate can take any vertical orientation, horizontal or other, depending on the use that is made of the concrete structure. The structure of the concrete may be devoid of reinforcement such as irons.

Embossed printing process

According to another of its aspects, regardless of the formation of asperities on concrete, or additionally, the invention relates to a method of decorating a concrete structure, comprising the following steps: a. coating a permeable substrate with a photosensitive emulsion, b. exposing the substrate thus coated with the emulsion to a radiation source so as to form an image on the substrate, c. developing the emulsion so as to have a local permeability of the substrate related to the image, d. affixing the substrate after developing the emulsion on at least one face of the concrete structure, e. depositing on the concrete structure, through the substrate, a mixture comprising a varnish and / or a coloring agent, including luminescent or phosphorescent, so as to reveal an image-related pattern on the concrete structure, f . allow to dry, for example from a few hours to several days, or, a. coat the concrete structure with a photosensitive emulsion, b. exposing the structure thus coated with the emulsion to a source of light radiation so as to form an image on the structure, c. developing the emulsion so as to have local permeability of the image-related structure, and d. optionally, depositing on the concrete structure, a mixture comprising a varnish and / or a coloring agent, including luminescent or phosphorescent, so as to reveal an image-related pattern on the concrete structure, e. let dry, for example from a few hours to several days, f. possibly place the concrete structure on which the mixture has been deposited in hydrochloric acid.

The substrate may for example comprise a frame fabric, which is coated with photosensitive emulsion, during the first step a.

The face of the structure on which the substrate is affixed may for example correspond to the "smooth side" of a concrete slab, that is to say the side located against a wall of the mold during setting concrete.

Before affixing the substrate to the concrete structure, it is for example possible to treat the face on which the pattern will appear by proceeding to its degreasing, for example with a solvent such as acetone.

FIG. 2 illustrates steps of an exemplary method according to the invention, enabling the creation of a pattern on the surface of a concrete structure, according to a principle similar to that of screen printing. The concrete used is for example a type of concrete BFUP (Ultra Fiber Concrete

High Performance) having a particle size preferably of less than 500 microns.

Firstly, in a first step I degreasing a face of the concrete structure 1 on which the printing will be performed, for example using a cloth 3 soaked in a solvent such as acetone. In a second step II, a screenprint 4 is produced on which a frame fabric 5 is shown.

The preparation of the artwork 4 consists of coating the canvas on frame 5 with photosensitive emulsion while working in a space of reduced brightness, for example in a dark room. Then, the photosensitive emulsion is allowed to dry. At the end of this period, the desired pattern is insolated on the artwork and once the sunstroke is over, the artwork is rinsed with water and allowed to dry.

Then, a mixture M intended to be applied to the artwork 4 in order to reveal the desired pattern on the chosen surface of the concrete structure is prepared.

This mixture M may for example comprise an ink, or pigments mixed with a binder, for example a glossy varnish.

Luminescent photo-pigments may optionally be incorporated into the mixture M. In this case, the screen-printing type 4 is preferably chosen so as to have a large mesh and these pigments are present in a mass content preferably greater than or equal to 20%, more preferably 30%, in the mixture M.

The presence of the varnish within the mixture M may be useful if it is desired subsequently to deposit an acid on the concrete structure, in order to etch the surface thereof and to remove the skin from the concrete on the regions not covered by the mixture M, that is to say the outer layer of the structure having a very thin structure, a few microns thick.

In step III, the artwork 4 is affixed to the concrete structure 1, possibly placing shims 6 around the concrete structure 1, on which the frame of the artwork 4 is placed, so as not to perforate the fabric 5 with the angles of the concrete slab 1.

The mixture M is then deposited by spreading through the fabric 5, for example using a squeegee, making one or more passes and allowed to dry.

The fabric 5 has a permeability function of the image, so that the mixture M is deposited selectively on the concrete structure and forms the image that is sought to reproduce.

In the last step IV, the concrete slab 7 is allowed to dry for a sufficient period.

The concrete structure can also be engraved by placing it on the serigraphed side of the mixture in hydrochloric acid.

Multicolored structure

According to another of its aspects, independently of the above-mentioned aspects, or additionally thereto, the subject of the invention is also a method of manufacturing a concrete structure, comprising the following steps: casting a thin thickness, in particular between 0.5 mm and 5 mm, concrete A in the bottom of a mold and then pour over a concrete B, these concrete A and B being of different colors, one of concrete A and B being intended to form the outer skin of the concrete structure and having a water content sufficiently low to crack on drying with preferably no fibers or low fiber content, and reveal, in the bottom of the cracks, the other concrete, thus creating a contrast effect between the colors of concrete A and B.

The invention also relates to such a structure, comprising a skin of a concrete having a first color, covering a core of a concrete of a second color, the skin being cracked and the color of the heart appearing in the bottom of cracks.

Figure 3 very schematically shows such a structure.

In this example, the concrete A forms the skin of the structure, cracked and traversed by cracks 26. The concrete B which forms the heart is exposed to the view through these cracks. The thickness of the skin is for example between 0.5 mm and 5 mm.

The cracks 26 may optionally be filled with a resin, in particular a transparent resin.

To achieve the concrete structure, can be cast as shown in Figure 4 a light layer of concrete A in the bottom 23 of a mold 22, then flows immediately after and gently concrete B on the concrete layer A.

Concretes A and B are obtained for example as follows:

A: BHUP concrete without fibers and with less water than the conventional dosage provides.

B: BHUP concrete comprising the maximum of similar elements with A to facilitate cohesion. A BFUP concrete used for B will provide greater strength for the A + B assembly.

In a variant, a large layer of concrete B is poured into the bottom 23 of a mold 22 to form the core of the structure, then a thin layer of concrete A is poured onto the concrete layer B to form the skin. . After drying and demolding, it is possible to sand the concrete structure obtained.

The first way advantageously allows to exploit the side of the concrete plate in contact with the bottom 23 of the mold 22, that is to say the side that can be smoother, while the second variant allows to exploit the side free of the concrete plate, that is to say the side opposite the bottom 23 of the mold 22, may have a more random appearance. The concrete structure may be used as a structural and / or decorative work within a building or as furniture, eg table, chair, countertop, siding, paving,

This process can be combined with that of craters to obtain craters of different colors.

Thus, after casting concretes A and B in the mold, the evacuation of the air bubbles can be thwarted by the presence of a solid part in the upper part of the mold, the concrete adjacent to this solid part having a sufficiently thick weak so that the craters that form during the setting of the concrete let appear the underlying concrete, of different appearance.

Modular elements

According to another of its aspects, the invention also relates to a concrete module of BHT (High Performance Concrete) or higher quality to achieve a modular structure, this module comprising perforated cells made by molding the concrete of the module, the cells being joined to each other, these cells being at least two different sizes and being arranged in such a way as to allow the modules to be assembled to be brought together sufficiently to obtain an impression of visual continuity between the modules thus assembled. Each module may for example have more than three, better four, even better five different cell sizes.

The openings of the cells can be circular, with for example large circles which have a diameter at least double, better at least triple, that of small circles. The modules can be assembled together in different ways, to create structures of varying sizes and shapes, able to adapt to the environment in which they are located.

The various structures can be affixed against the surface of one or more building walls, so as to easily adapt to the spatial configuration of the walls, especially in the corners or at the intersections between two walls or act as a trellis, separating interior partitions between two spaces. The openings of the cells may have different shapes, especially other than circular, for example polygonal, in particular rectangular, square or triangular, oval, star, among others.

The openings of the cells can be filled at least partially with filling elements in order to create new effects or to reinforce the structure thus obtained.

These elements completely fill for example at least one ajour of a cell of the structure, may or may not let the light.

These elements can be made for example from a colored resin, transparent or translucent.

The proportion between the cells in the openings is filled and those left empty can for example be less than 1 open filled for 4 empty openings.

The filling elements intended to fill the cells can still be opaque or integrate light systems or loudspeakers. The height of a module is for example between 0.5 and 3 m, better 0.8 and 1.2 m.

The thickness of a basic module is for example between 8 and 100 mm, preferably between 12 and 45 mm.

Figures 5 and 6 show, in front view, two examples of modules 60 and 70 having hollow cells 80 of circular shape, with a variable diameter.

FIG. 7 represents, in perspective, the module 70 of FIG.

The construction material used to produce the modules is, for example, BFUP type concrete.

The modules 60 and 70 have for example a thickness of 35 mm and a height of 1 m.

FIG. 8 represents, in front view, the module 70 of FIG. 6, in which replacement elements 81 made of green translucent resin have been introduced into some of the units 80 of the same diameter.

FIG. 9 illustrates different possibilities of assembling the modules 60 and 70 of FIGS. 5 and 6.

The assembly may depend on the spatial configuration of the place where the modules are placed, or result from a personal choice. In particular, for a given space where there is a choice between two different models of modules, and three different locations to place these modules, it is possible to obtain eight different configurations in the positioning of the modules. Figure 9 illustrates three of these eight possible configurations for modules

60 and 70.

The modules are arranged to have a certain visual continuity when close together.

The contact areas between the two adjacent modules can be defined by cells.

The perimeter of a module can be defined for example by at least five different cells.

Of course, the invention is not limited to the embodiments which have just been described above. In all the alternative embodiments illustrated in this application, the concrete structure may incorporate at least one electronic sensor, in particular a proximity sensor, for example of the capacitive type, and / or at least one loudspeaker.

The phrase "with one" should be understood as being synonymous with "having at least one".

Claims

A method of manufacturing a concrete structure, comprising the steps of:

counteracting the evacuation of the air bubbles at the upper surface of the concrete, so as to reveal asperities during the setting of the concrete,

- To vibrate the mold so as to evacuate at least partially the air bubbles contained in the concrete.

2. Method according to claim 1, the evacuation being thwarted by a solid part, in particular a plate, for example of area greater than or equal to 1 cm ² .

3. Method according to claim 2, the solid part only partially covering the upper surface of the concrete.

4. Method according to any one of claims 1 to 3, the asperities having for some at least, a diameter greater than or equal to 1 mm.

5. Method according to claim 4, the number of asperities having such dimensions being greater than or equal to 1 by dm ² .

6. Method according to any one of the preceding claims, the asperities being filled at least partially with the aid of a resin.

7. Method according to any one of the preceding claims, air being injected into the concrete before and / or after pouring into the mold, preferably before fixing the solid part annoying the evacuation of the bubbles and before the implementation. vibration at all.

8. Method according to any one of the preceding claims, a material being introduced into contact with the concrete before setting.

9. A method according to any one of claims 1 to 8, the structure being demolded and arranged to expose to view, during use of the structure, at least a portion of the surface having the asperities.

10. Method according to any one of claims 1 to 9, the structure being a piece of furniture, including a table or a chair, a floor covering, a building element.

11. Method according to any one of the preceding claims, optical fibers being arranged in the mold before pouring the concrete.

12. A method of decorating a concrete structure, comprising the following steps: a. coating a permeable substrate with a photosensitive emulsion, b. exposing the substrate thus coated with the emulsion to a source of light radiation so as to form an image on the substrate, c. developing the emulsion so as to have a local permeability of the substrate related to the image, d. affixing the substrate after developing the emulsion on at least one face of the concrete structure, e. depositing on the concrete structure, through the substrate, a mixture comprising a varnish and / or a coloring agent, including luminescent, so as to reveal an image-related pattern on the concrete structure, f. allow to dry, for example from a few hours to several days, or, a. coat the concrete structure with a photosensitive emulsion, b. exposing the structure thus coated with the emulsion to a source of light radiation so as to form an image on the structure, c. developing the emulsion so as to have local permeability of the image-related structure, d. optionally, depositing on the concrete structure, a mixture comprising a varnish and / or a coloring agent, including luminescent or phosphorescent, so as to reveal an image-related pattern on the concrete structure, e. allow to dry, for example from a few hours to several days, f. optionally, placing the concrete structure on which the mixture has been deposited in hydrochloric acid.

13. A method of manufacturing a concrete structure, comprising the following steps: a. casting a thin thickness, in particular between 0.5 mm and 5 mm, of concrete (A) in the bottom of a mold then, b. pour over a concrete (B), these concretes (A) and (B) being of different colors, one of the concretes (A) and (B) being intended to form the outer skin of the concrete structure and having a sufficiently low water content to crack on drying , preferably with no fibers or a low fiber content, and show, in the bottom of the cracks, the other concrete, thus creating a contrast effect between the colors of the concrete (A) and (B).

14. Module (60; 70) made of concrete of BHT (High Performance Concrete) quality or higher to produce a modular structure, this module comprising perforated cells (80) made by molding the concrete of the module, the cells being joined together others, the cells being at least two different sizes and being arranged in such a way as to allow the modules to be assembled to be brought together sufficiently to obtain an impression of visual continuity between the modules thus assembled.