FR2795359A1 - Method for the fabrication of mural cladding plates in light concrete and the plates thus obtained, having the aesthetic qualities of plates made from natural stone but lighter in weight - Google Patents

Abstract

A method for the fabrication of mural cladding plates in light concrete comprises:- a) a mortar is cast into the bottom of a mould to produce the layer with the visible face of the plate, this mortar being made up of 15 to 40 % by volume of hydraulic binder, 40 to 75 % by volume of sand, 0.1 to 1 % by volume of fibres, 5 to 10 % by volume of meta kaolin, an anti-shrinking additive, a plasticizing additive and water; b) the cast mortar is then vibrated; c) a layer of light concrete, with a composition consisting of 15 to 45 % hydraulic binder, 30 to 60 % glass sand, 5 to 15 % meta kaolin, 3 to 8 % sand, 0.5 to 2 % alkali resistant glass fibres, water and additives, is cast on top of the layer of vibrated mortar; d) the product is dried for a first time to allow it to be removed from the mould and it is then fully dried outside the mould; and e) the visible face of the plate is then finished.

Description

The present invention relates to a process for the production of lightened concrete wall covering plates and to the plates obtained by this process.

There are many techniques for wall cladding. One of these consists of making a covering of natural stone slabs, for example marble, granite or other materials that can be cut into relatively thin slabs.

Such trim plates are aesthetically perfect but the nature of the material requires the respect of a certain thickness of the plate to ensure its holding. This results in a very heavy coating. This is cute on the means of attachment or stapling of the plates on the wall or wall, on the transport and more generally on the total cost of the operation.

The same difficulties exist for slabs or wall covering plates of reconstituted materials, for example made of concrete.

The present invention aims to develop a method of manufacturing wall covering plates allows both to achieve concrete plates having all the aesthetic qualities of natural stone slabs or concrete without presenting the disadvantages particularly related to weight.

For this purpose, the invention relates to a method of the type defined above, characterized in that A) a mortar is cast in the bottom of a mold to make the layer of the apparent face of the plate, this mortar having the following composition - 15 to 40% vol. hydraulic binder, - 40 to 75 vol. sand, 0.1 to 1% vol. fiber, - 5 to 10% vol. metakaolin, - an anti-shrinkage adjuvant, - a plasticizing admixture, - water, B) the mortar layer thus poured is vibrated, C) pouring on the layer of vibrated mortar, a layer of lightweight concrete having the next composition - 15 to 45% vol. hydraulic binder, - 30-60% vol. of glass sand, - 5 to 15% vol. of metakaolin, - 3 to 8% vol. sand (0-1 mm), - 0.5 to 2% of alkali-resistant glass fibers, - water and admixture, D) a first time to allow the demolding of the product, then the oven again to allow the finish of the product, E) the finishing of the apparent face of the plate is carried out. It is particularly interesting to cast a slab of a certain size corresponding to the surface of several plates, then, at the end of manufacture, to cut the slab into slabs. This process not only simplifies the manufacturing process, but also allows for a greater variety of plate sizes, which can be cut on demand for special wall coverings, pattern creation or dimensional integration. which are not a multiple of standardized dimensions.

The finish of the exposed face can be a polished finish, sanded, brushed, or a coating of gelcoat applied directly to the bottom of the mold, before concreting lightweight concrete.

In all cases, the plate made according to the invention combines the characteristics of a perfect aesthetic for the visible face, which is the result sought for a wall covering, while being of a very low weight, facilitating operations transportation, handling and installation of such a wall covering.

The present invention will hereinafter be described in more detail with the aid of various exemplary embodiments shown in the accompanying drawings in which: - Figure 1 is a schematic of the method of manufacturing wall covering plates according to the invention; FIG. 2 is a perspective view of a plate, FIG. 3 shows the installation of a wall covering made of plates according to the invention.

According to FIG. 1, the process for manufacturing lightened concrete wall covering plates consists, during a first operating phase, in pouring a mortar into the bottom of a mold in order to make the layer of the apparent face of the plate (AT). The bottom of the mold gives the pla that its final appearance. This background can be smooth. It may also include a repetitive or unique pattern. The mortar poured into the bottom of the mold has the following composition - 15 to 40% vol. hydraulic binder, - 40 to 75 vol. sand, 0.1 to 1% vol. fiber, - 5 to 10% vol. metakaolin, - an anti-shrinkage adjuvant, - a plasticizer, - water.

The hydraulic binder used is cement. The sand preferably has a particle size of between 0 and 4 mm.

The fibers are 6 to 12 mm long fibers of alkali-resistant glass or polypropylene material.

The plasticizing admixture is a classic concrete admixture. This plasticizer can also be a super plasticizer.

After this pouring of the mortar, the layer (B) is vibrated to degas it and to give it the compactness required for the topcoat or outer layer. After this operation, a layer of light concrete (C) is poured to complete the plate. This layer of lightweight concrete preferably has the following composition - 15 to 45% vol. hydraulic binder, - 30-60% vol. of glass sand, - 5 to 15% vol. of metakaolin, - 3 to 8% vol. sand (0-1 mm) - 0.5 to 2% alkali-resistant glass fibers, - water and admixtures.

The binder is cement.

The glass sand with micro-beads is a sand with a particle size of 0.25 / 0.5 mm.

The plate then goes into an oven (D).

After these first manufacturing steps (A-D), the plate is demolded. It goes back to an oven and we finish the apparent face (E). This finish may consist of polishing, sanding, brushing or rough surface type gelcoat. The thus cast and finished plate can be cut into smaller sized plates. Such an operation is interesting because with a large mold can significantly simplify the manufacture of plates and cut plates to the desired dimensions, if necessary on demand. In addition, the cutting achieves, by the same operation, the sharp edge bordering the sides of the plate. In the case of making separate plates in each mold, it is generally necessary to complete the above operation by treating the edges of the plate, for example by cutting or sanding to obtain sharp edges and regular.

Figure 2 is a partial perspective view of a plate according to the invention. This plate 1 consists of a layer 2 forming the apparent face 3 and a lightened concrete layer 4 integral with the layer 2 of the apparent face. The junction of the two layers is represented by the surface 5, generally irregular.

The apparent layer 2 represents at most 1/4 of the total thickness.

The vertical schematic cross-sectional view of FIG. 3 shows the attachment of plates 11, 12, 13. For this purpose, in a wall 10, brackets 14, 15, 16 are fastened, following horizontal lines, then plates 11-13 are installed. The gap (e) between the plates is defined by the standards. Each plate rests on one or more legs 14, 15, 16 by its lower edge. Fixing is also done with a pin 20 introduced into locations 6 of the plates.

The tab 14 which belongs to the row of agra fes, above the upper edge of a plate 11, can touch this edge or be at a distance from it. This tab 14 supports the plate 12 or the row of plates coming from above.

The fixing of the plates coming from above is done by the introduction into the studs 20, placed in the upper edge of the plate or plates located underneath, if necessary through the tabs. One can also provide an assembly bringing together the upper edge and the lower edge of two superimposed plates with play, and interposi tion of a trunnion not necessarily passing through a latching lug.

The manufacturing process makes it easy to produce dimensions on demand.

Claims (1)

<1> A process for producing lightened concrete wall cladding panels, characterized in that A) a mortar is cast in the bottom of a mold to form the layer of the visible face of the mold. the plate, this mortar having the following composition - 15 to 40% vol. hydraulic binder, - 40 to 75 vol. sand, 0.1 to 1% vol. fiber, - 5 to 10% vol. metakaolin, - an anti-shrinkage adjuvant, - a plasticizing admixture, - water, B) the mortar layer thus poured is vibrated, C) pouring on the layer of vibrated mortar, a layer of lightweight concrete having the next composition - 15 to 45% vol. hydraulic binder, - 30-60% vol. of glass sand, - 5 to 15% vol. of metakaolin, - 3 to 8% vol. sand (0-1 mm), - 0.5 to 2% alkali-resistant glass fibers, - water and admixtures, D) a first time to allow the demolding of the product, then it is heated again to allow the finish of the product, E) the finishing of the apparent face of the plate is carried out. 2) Method according to claim 1, characterized in that a slab is cast representing the surface of several pla ques according to steps A-E and then cut the slab plaques. 3) Process according to claim 1, characterized in that the finishing step is a polishing operation, sanding or brushing. 4) Process according to claim 1, characterized in that the finishing step consists in applying a gelcoat coating to the bottom of the mold before concreting lightweight concrete. 5) Plate obtained by the implementation of the method according to any one of claims 1 to 4, characterized in that it consists of a surface layer (2) with the finishing face (3) and to the back of a light concrete layer (4).