WO1998039526A1

WO1998039526A1 - Prefabricated partition

Info

Publication number: WO1998039526A1
Application number: PCT/FR1998/000428
Authority: WO
Inventors: Laurent Gromier
Original assignee: Onduline
Priority date: 1997-03-04
Filing date: 1998-03-04
Publication date: 1998-09-11
Also published as: RU2199634C2; ES2152193T1; FR2760476B1; EP1015710A1; TR199902143T2; FR2760476A1; PL335503A1; DE1015710T1

Abstract

The invention concerns a prefabricated partition comprising two insulating walls (1, 2) separated by a space in which is placed a cellular structure (3) fixed to the two walls 1, 2). The invention is characterised in that the cellular structure (3) is made up of individual cells (8, 9) and does not comprise parallel walls. The cellular structure (3) comprises bosses and/or recesses (7) forming cells.

Description

Prefabricated partition

The present invention relates to the field of construction and more particularly to prefabricated partitions.

Partitions are known which consist of two plaster-based panels, of given thickness, between which are intersected strips of cardboard. The cardboard intermediate part has voids, evenly distributed. It constitutes a honeycomb structure which is fixed to the plaster panels.

These panels are, in general, constituted by a plaster wall on which is fixed, on both sides, a sheet of cardboard. These sheets improve the strength of the plaster wall. For a partition whose thickness is approximately 7 cm, each plaster-based panel has a thickness of approximately 1 cm.

A new regulation, now in force for new constructions, aims to fight against noise. Tests are defined in order to measure the transmission of noise from one room to another. The noise transmission measured must be below a determined threshold before the construction can be placed on the market.

In practice, when this threshold is exceeded, additional acoustic insulation must be applied, such as insulating plates on the partitions. This leads to additional costs and reduces the area of the rooms.

Partitions intended for sound insulation are known from document GB-A-1 .205.295. This document presents an insulation panel intended to form part of, or cover, a wall, a ceiling, a partition or a door. This panel consists of two walls between which is disposed a molded structure having cavities whose shape is approximately that of a pyramid trunk and which are open alternately to one side or the other of the structure. The alternation of the openings of these cavities identical to each other is obtained by a chessboard arrangement of the cavities open respectively to one side or to the other. It follows a symmetry of the molded structure with itself with respect to a median plane. To receive the sound to be attenuated, one of the two walls is provided with slots through which the sound enters the cavities open towards them. The sound is then transmitted to the adjacent cavities, which are closed, to be attenuated there.

The builders wish to use products which each contribute to the acoustic insulation of the building.

The object of the invention is therefore to propose a prefabricated partition whose cost and dimensions are substantially identical to those of conventional prefabricated partitions, and which has substantially higher sound or acoustic insulation q ualities, by limiting transmission through the bulkhead of the noise generated on one side of the bulkhead.

The object of the invention is achieved with a prefabricated partition comprising two insulating walls separated by a gap in which is placed a honeycomb structure, having bosses which form cells, each boss having an apex. The honeycomb structure is fixed to the two insulating walls by the tops of the bosses.

According to the invention, the honeycomb structure is composed of individual cells and does not have parallel walls.

This arrangement of the invention makes it possible to avoid the phenomenon of standing waves and thus improve the efficiency of the sound insulation of the partition.

Recall that the standing wave phenomenon is an interference phenomenon due to the superposition of two or more vibrations of the same period or multiple period. By placing a structure between the insulating walls of the partition which is free, at least essentially, of surface elements which are parallel to each other or parallel to the facing surfaces of the two insulating walls, this avoids practically the formation of standing waves in the interval between the insulating walls.

The invention also relates to the following characteristics taken into consideration in isolation or in all their technically possible combinations:

- The bosses are arranged in a matrix arrangement in columns and lines and so that the tops of the bosses of two adjacent lines are oriented in opposite directions, the cells formed by the bosses then being open, line by line alternately, towards one and towards the other of the two insulating walls.

- The shape of the bosses corresponds approximately, depending on the variant chosen, to that of a paraboloid, a cone or a pyramid, the end of which has been deformed enough to constitute a contact surface for fixing the structure dimpled on the insulating walls.

- The open cells to an insulating wall and the open cells to the other insulating wall are formed so as to give the honeycomb structure, in cross section, an asymmetrical shape.

- The honeycomb structure is made so as to allow the passage of pipes and / or cables, without perforation of the cells.

Advantageously, the bosses are formed so as to limit passages between corresponding bosses and the facing wall over the entire length and / or width of the partition.

- The honeycomb structure is made of suction molded cellulose.

- The insulating walls have a different thickness.

Advantageously, the ratio between the thicknesses of the two walls is different from a multiple of 0.5.

The realization of the honeycomb structure in molded cellulose and the granting of a difference between the thicknesses of the two insulating walls, each in its own way, contribute to an additional improvement in sound insulation. The molded cellulose has a rough surface, at least on one side, which reduces wave reflection. And the difference between the thicknesses of the walls avoids the phenomenon of resonance.

- The honeycomb structure consists of a single piece.

- The honeycomb structure is made up of several elementary panels.

- The elementary panels are arranged in strips, offset from each other.

- The partition has, over its entire periphery, a thin wall, to improve its mechanical strength, in particular its resistance to torsion.

- At least one insulating wall is constituted by a plaster panel on which are fixed sheets of cardboard.

Other advantages and characteristics of the invention will appear on reading the following description of two embodiments of the invention, made in relation to the appended drawings in which:

Figure 1 shows in perspective a prefabricated partition according to a first embodiment of the invention, with a partial cutaway.

Figure 2 shows, in detail, the honeycomb structure of the partition of Figure 1.

Figure 3 shows in perspective a prefabricated partition according to a second embodiment of the invention, with a partial cutaway.

Figure 4 shows part of a mold to obtain the honeycomb structure of the partition in Fig ure 3.

Fig ure 5 shows a cross section along a line VV of part of a honeycomb structure obtained with the mold of Figure 4, and Figure 6 is a partial and schematic plan view of a honeycomb structure made of elementary panels.

The elements common to the different figures will be designated by the same references.

The prefabricated partition of the invention has two insulating walls 1 and 2, separated by a gap in which is disposed a honeycomb structure 3 or 103.

The height, or thickness, of the honeycomb structure corresponds to that of the interval between the two walls 1 and 2.

The shape of the honeycomb structure varies depending on the embodiment, but the structure always includes bosses or recesses, depending on the direction of observation, arranged in a matrix arrangement and defining individual cells.

The honeycomb structure 3 shown in Figure 2 has bosses 7, each boss 7 having a vertex 1 5. The bosses 7 are arranged so that all the vertices are oriented towards the same side of the structure 3, in the example shown towards the side intended to be opposite the insulating wall 1. The bosses 7 generally have a unique shape and dimensions and together form individual cells 8 open towards the opposite side with respect to the vertices 1 5 and cells 9 open towards the same side as the vertices 15.

Indeed, industrial production is simpler by repeating the same pattern. However, a variation in shapes and dimensions can improve the qualities of the product.

Each cell 8 is defined by an arcuate wall 1 0, curved around an axis A, and two transverse walls 1 1 and

12 extending in transverse planes relative to the axis A. In the example shown, the cell 8 resembles approximately half of a straight cylinder, the section plane being parallel to the axis A. transverse walls 1 1 and 12 are approximately, but not necessarily, planes and extend along planes which are not parallel to each other, for example in such a way that the two transverse walls of a cell are slightly inclined towards one another, seen in the direction of the top of the alveolus.

Thanks to the arrangements described above, both the honeycomb structure as a whole and each of the individual cells do not have parallel walls, neither in the direction of the orientation of the axes A, nor in a transverse direction T constituting the direction main transmission of phonic waves.

The cells 8 of the honeycomb structure 3 are arranged in a matrix pattern, a series of consecutive cells being aligned along the same axis A, and several series of cells being arranged one parallel to the other.

The cells 8 of the same series are separated from each other by free spaces 13, each of the spaces 1 3 being defined between the transverse wall 1 1 of a cell 8 and the transverse wall 12 of the cell next. Each free space 1 3 communicates, in the transverse direction with respect to the axis A, with the corresponding space 13 of the series of neighboring cells.

The cells 8 of two neighboring series define between them free spaces 14, each of the spaces 14 being formed between the opposite parts of the arcuate walls 10 of two neighboring cells. Each free space 14 communicates, in a direction parallel to the axes A, with the corresponding space 14 formed between the two following cells.

Furthermore, the consecutive free spaces 14 and the neighboring free spaces 13 defined between four cells 8 forming an elementary square matrix of cells, communicate both with one another and with the adjacent free spaces 1 3 and 14. The free spaces 1 3 and 14 indifferently constitute cells 9.

On the opposite side with respect to the tops 1 5 of the cells 8, the latter are interconnected by thin elements 16 and 17 hereinafter called edges regardless of their true shape in an embodiment of the invention. The edges 16 and 17 are shown in Fig ures 1 and 2 in an exaggerated manner with respect to the dimensions of the cells, for drawing reasons. The edges 16, oriented parallel to the axes A of the cells, and the edges 17, oriented transversely with respect to the axes A, constitute both the bottom respectively of the free spaces 14 and of the free spaces 13 and the tops of the cells 9. Thus, an edge 16 connects the arcuate walls 1 0 of two neighboring cells 8, and an edge 17 connects the transverse wall 1 1 of a cell with the transverse wall 12 of the next cell.

The honeycomb structure 3 is fixed to the insulating walls 1 and 2 by ends, in particular the vertices 15 and the edges 16 and 17 of the bosses 7. It is understood that the vertices 15 as well as the edges 16 and 17 can be fixed on the corresponding insulating wall 1 or 2, either entirely or partially, for example by dots of glue.

Thanks to the shape and arrangement of the cells 8 and 9, their ends are located so that the ends facing one side of the honeycomb structure are not disposed opposite the ends facing the other side of the honeycomb structure . As a result, the insulating walls

1 and 2 of a partition according to the invention are connected by elements which, apart from the arcuate shape of the walls 10 of the cells, extend in planes out of the normal with respect to the planes of the greatest extent of the insulating walls 1 and 2, which contributes significantly to improving the insulation of the partition.

The insulating walls can be constituted for example by plaster panels coated on each of their large sides with a sheet of cardboard. These plaster-based walls preferably have a different thickness in order to avoid resonance phenomena. To further avoid resonance to a harmonic, the ratio between the thicknesses of the two insulating walls must not be a multiple of 0.5. They can in particular be of the type referenced BA 13 and BA 10.

The honeycomb structure 103 is shown in Fig ure 4, and in detail in Figure 5, by a mold 100 by means of which it can be obtained. Compared to the representation of the structure 103 in Figure 3, the shapes of the upper surfaces of the mold 100 correspond to the lower surfaces of the honeycomb structure 1 03. To simplify the drawing and description, the mold 1 00 is shown in the Figures 4 and 5 only by the part giving the structure 1 03 the bosses forming the individual cells. The auxiliary parts necessary for integrating the mold into a machine and for its operation are omitted. Consequently, the following description of the mold 100, in particular as regards the shape and the arrangement of the bosses, of the cells and of the edges is also valid for the structure 103.

The mold 100 includes bosses 107 the shape of which roughly corresponds to that of a pyramid, the top of which has been slightly deformed so as to obtain the honeycomb structure of the contact surfaces for fixing it to the insulating wall 1 or 2, for example, with glue. The ends, or vertices, of the bosses 1 07 are referenced 1 15 and 1 18.

Each boss 107 has the shape of a truncated pyramid having four large lateral faces 151 to 1 54, trapezoidal each, four small lateral faces 1 55 to 1 58, connecting the large lateral faces in a bevel, and a non-planar face 159 corresponding to the truncation of the pyramid. The base of the pyramid constitutes the opening of the cell formed by the boss. The inclination of the large lateral faces with respect to the axis of symmetry B of the truncated pyramid is chosen such that the angle α formed by two large opposite faces is of the order of 40 ° to 50 °.

The non-planar faces 159, which correspond to the bottoms 1 15 and 120 of the cells formed by the bosses, are provided with an orifice referenced 1 19 or 1 18 depending on the cell considered. These orifices or passages make it possible to form the honeycomb structure 103 by suction, as is explained below.

The bosses 107 are arranged in a matrix arrangement in columns C and in lines L and in such a way that their end is oriented alternately towards one side or towards the other of the two sides intended to be placed opposite one or the other. other of the two insulating walls of the partition according to the invention. In the example shown, all the bosses 107, the end of which is referenced 1 15 and which correspond to the cells 108, are oriented so that the opening of the cell shows downwards. On the honeycomb structure 103, this corresponds to the side intended to be placed opposite the insulating wall 1. Similarly, the bosses 107, the ends of which are referenced 1 1 8 and which form cells 109, are open upwards, which corresponds on the structure 103 to the side intended to be placed opposite the insulating wall 2.

To simplify the description, the bosses 107 are shown in Figures 3 and 4 so that the individual cells 108 and 109 have the same shape and the same dimensions. However, it is understood that the bosses can be made so as to obtain an asymmetrical structure, the cells 108 being, for example, larger than the cells 109.

Similarly, according to the embodiment shown in Figure 4, the mold 100 includes edges 1 16, 1 17 which extend between the bosses forming cells of the same reference.

More particularly, Figure 4 shows edges 11 16 extending between the bosses forming the cells 109 of the same column of bosses and edges 17 extending between the bosses forming the cells 109 of the same line of bosses. The shape of the edges 1 16 and 1 17 can be chosen freely, in particular as regards the curvature of the arcuate part. Thus, the edges 1 16 and 1 17 can have a curved shape as pronounced as that shown in Figure 4 or a less curved shape. The one or the other can also be substantially straight and correspond in this to the edges 16 and 17 according to the first embodiment of the honeycomb structure 3. Finally, the edges 1 16 and 1 17 can be arranged on one side or from the other from the mold or on both sides.

Depending on the shape and dimensions of the edges 1 16 and 1 17, pipes and / or cables can be housed in one direction or the other between the honeycomb structure 103, obtained by the mold 100, and one and / or the other of the insulating walls 1 and 2. In this aspect, a honeycomb structure made up of bosses 107 which form cells 108 and 109 of identical shapes and dimensions, and which has no edges 1 16, 1 17 or which has arcuate edges of strong curvature, offers the greatest choice for the arrangement of pipes and / or cables between the honeycomb structure 103 and one or the other or both of the insulating walls 1 and 2.

I ndepending on the size and shape of the cells 108 and 109, the honeycomb structure 103 advantageously has two different surface states on one side and on the other.

Indeed, the honeycomb structure 103 is obtained from a pulp or pulp of cellulose applied to a mold whose shape corresponds to that shown schematically in Figure 4. The transverse channels 1 19, 120 of this mold allow to apply a suction force to the mold so as to make the pulp or pulp of cellulose marry the surface of the mold.

The molding of the honeycomb structure 103 by suction towards a mold constituted by a single piece, as opposed to molding by means of two molds of complementary shape between which the pulp or pulp of cellulose is pressed, makes it possible to give the honeycomb structure 103 a smooth surface on one side and rough surface on the other side. It is understood that the smooth surface can be replaced by a non-smooth surface reproducing, in the complementary form, the shape of the mold surface.

Having a rough surface at least on one side of the honeycomb structure means that the thickness of the material of the honeycomb structure is not constant, but varies randomly along the extent of the honeycomb structure. Both the variation in the thickness of the material and the rough surface (s) each contribute in its own way to improving the sound insulation result of the partition according to the invention. While the variation in the thickness of the material contributes to attenuating the transmission of sound through the material of the honeycomb structure, the rough surface attenuates the reverberation of sound between the honeycomb structure and the insulating wall on which the honeycomb structure is fixed. side of the rough surface.

Regarding the choice of the material in which the honeycomb structure is made and the preparation of the cellulose pulp or pulp constituting the material of the honeycomb structure, the following indications are given: • Molded cellulose is preferred to paper and cardboard because the molded cellulose comprises fibers of very varied dimensions and in particular little oriented. It includes very diverse charges, for example from recovered paper and cardboard. • The density of molded cellulose, in the dry state, is around 0.3.

• The molded cellulose is obtained essentially in four stages, namely:

- pulping, grinding of old paper and cardboard in an aqueous mixture comprising approximately 15% of cellulose and 85% of water;

- dilution of the pulp to obtain a concentration of the order of 1% of cellulose, ie 99% of water;

- application of the paste on a mold and suction molding;

- drying.

• The loading rate is advantageously of the order of 14%, the pulp comprising approximately in equal parts mechanical pulp, such as newsprint and chemical pulp.

Analogously to the honeycomb structure 3, and as shown in FIG. 3, the honeycomb structure 103 is fixed to the insulating walls 1 and 2 by the ends 1 15 and 11 of the cells 108 and 109. The insulating walls can be of the type referenced BA 13 and BA 10.

I ndepend on the chosen embodiment of the honeycomb structure, it has, for example, a thickness of 4.7 cm. The thickness of the partition according to the invention in this case has a standard thickness of 7 cm.

The prefabricated partition according to the invention may in particular have standard dimensions for this type of partitions and which are: in height: 250 cm, in width: 120 cm and in depth: 7 cm.

Thus, transport, storage and installation technique are unchanged compared to the classically used partitions. Figure 6 schematically shows a honeycomb structure consisting of elementary panels 4 arranged in strips 5, offset from each other.

Such panels are generally in the form of squares of 30 cm side, which is suitable for a partition width of 120 cm.

One can also provide honeycomb structures composed of panels of larger dimensions or even made in one piece. In all cases, the honeycomb structure is made so as to allow, in particular laterally or longitudinally, the possible passage of pipes and / or cables, without perforating the cells.

On the edge or the periphery of the partition, is advantageously fixed a thin wall 6 like a ribbon or a strip of cardboard to close the partition.

This improves the mechanical strength of the partition, and in particular the resistance to torsion.

Tests have been carried out to compare the acoustic performance of the prefabricated partitions according to the invention with several types of conventional partitions: a partition made of hollow plaster tiles having a thickness of 7 cm; a prefabricated partition comprising, between two plaster-based panels, a structure of crisscrossed cardboard strips and having a thickness of 7 cm and finally, a prefabricated partition of the same type but with a thickness of 5 cm.

The tests consisted in measuring the level of noise transmitted through each of the four selected partitions. They have demonstrated that the partition according to the invention, with a thickness of 7 cm, allows an improvement in the reduction of the transmission of noise of between 7 dB and 13 dB compared to the three other partitions, conventionally used in construction. The use of the partition according to the invention makes it easier to meet the new regulations, without increasing the material and labor costs and without reducing the living space. Furthermore, the cost price of a prefabricated partition according to the invention is substantially identical to that of conventional partitions, since it is the price of the raw material and in particular of cardboard relative to the molded cellulose which is decisive. The reference signs inserted after the technical characteristics mentioned in the claims are intended only to facilitate the understanding of the latter and should not limit their scope.

Claims

1. Prefabricated partition comprising two insulating walls (1, 2) separated by a gap in which is placed a honeycomb structure (3, 1 03) having bosses (7, 107) forming cells (8, 9, 108, 109), each boss having a top and the honeycomb structure (3, 1 03) being fixed to the two insulating walls (1, 2) by the tops of the bosses, characterized in that the honeycomb structure (3, 103) is composed of individual cells and does not have parallel walls.

2. Partition according to claim 1, characterized in that the bosses (7, 107) are arranged in a matrix arrangement in columns and in rows and so that the vertices (15, 16, 17; 1 15, 1 18) bosses of two adjacent lines are oriented in opposite directions, the cells (8, 9; 108, 109) formed by the bosses (7, 107) being then open, line by line alternately, towards one and towards the other of the two insulating walls (1, 2).

3. Partition according to claim 1, characterized in that the cells (8, 108) open towards an insulating wall (2) and the cells (9, 109) open towards the other insulating wall (1) are formed so as to give the honeycomb structure (3, 1 03), in cross section, an asymmetrical shape.

4. Partition according to one of claims 1 to 3, characterized in that the honeycomb structure (3) is made so as to allow the passage of pipes and / or cables, without perforation of the cells.

5. Partition according to one of claims 1 to 4, characterized in that the honeycomb structure (3, 103) is in molded cellulose.

6. Partition according to one of claims 1 to 5, characterized in that the insulating walls (1, 2) have a different thickness.

7. Partition according to one of claims 1 to 6, characterized in that it comprises a thin wall (6), over its entire periphery.

8. Partition according to one of claims 1 to 7, characterized in that at least one insulating wall is constituted by a plaster panel on which are fixed sheets of cardboard.

9. Partition according to one of claims 1 to 8, characterized in that the honeycomb structure (3, 103) consists of several elementary panels (4).

10. Partition according to claim 9, characterized in that the elementary panels (4) are arranged in strips (5) offset from each other.