FR2970475A1 - Composition, useful as mortar to apply on a support or framework wood, comprises clay and sandy mud, crushed clay pots, a fibrous component comprising straw, preferably crushed barley and residue or wool, cellulose wadding, and water - Google Patents

Abstract

Composition (I) comprises clay and sandy mud, crushed clay pots, at least one fibrous component comprising straw, preferably crushed barley and residue or wool, cellulose wadding, and water. Independent claims are included for: (1) a container, preferably bag comprising 20-60, preferably 35 kg of (I) except water; (2) the preparation of (I) comprising adding water to the above mixture and mixing; and (3) a wall having a framework wood, where at least one side of the wall is coated with (I).

Description

Composition intended to be applied as a mortar on a support or a wood frame

The invention relates to the field of coatings "earth + fibers" also called cob. The invention relates more particularly to a composition based on mud and straw allowing a large scale implementation of these natural and ancestral materials.

For millennia, man uses mud made from raw earth mixed with vegetable fibers for the construction of houses or various works. These coatings based on natural materials are renowned and appreciated for their many benefits. The extraction, preparation and implementation of the raw earth involve very low energy requirements compared to other materials, including in comparison with the terra cotta (low gray energy). The raw earth is a material very available and widespread on the planet (no need to route it from a distance, to transform it). It offers excellent thermal inertia and has remarkable hygrometric control qualities. In addition, the raw earth brings to the plaster its consistency and cohesion. Natural fibers, especially straw, are also widespread and readily available. Straw is an excellent mechanical support ensuring the structural strength of the coating and its resistance to external forces and stresses. We also note that these materials are very inexpensive given their high availability and their use in the raw state (no or very little transformation).

However, it is observed that the implementation of traditional cob is done manually, in a very traditional way. This involves significant labor costs and a construction time difficult to compress according to traditional methods. In addition these known mud are not compatible with conventional machines used by artisans to apply conventional coatings or mortars on facades or walls. - 2

The object of the present invention is to overcome all or part of the above disadvantages by proposing a composition based on raw earth and fibers known for their qualities and properties, while being perfectly compatible with a large-scale use and low cost of manpower, thanks to the use of a traditional mortar machine facade.

For this purpose, the subject of the invention is a composition intended to be applied as a mortar on a support or a wood frame, this composition being constituted by a mixture of: - raw sandy clay, - crushed terracotta, - at least a fibrous constituent chosen from: * straw, in particular ground barley, * wool residues, - cellulose wadding, - water.

Such a composition constitutes a mixture that is perfectly suited to mechanized and industrial use from machines or installations to be sprayed that are conventionally found on the market, such as, for example, a "Putzmeister SP11" type machine. It is an optimized mixture that promotes adequate flow in the machine ducts, does not create lumps or plugs, yet is sufficiently fluid and homogeneous for use as a mortar or mud to be applied to facades or walls of various constructions. .

According to other advantageous features of the invention, the composition comprises the following proportions of ingredients, expressed in volumes: - between 5 and 7 volumes of raw clay sandy loam, - between 1 and 3 volumes of pounded terracotta, - between 2 and 4 volumes of fibrous constituent, - between 2 and 4 volumes of cellulose wadding. - between 3 and 5 volumes of water.35 - 3

According to still other advantageous characteristics of the invention, the composition comprises the following proportions of ingredients, expressed in volumes: - 6 volumes of raw clay sandy loam, - 2 volumes of crushed terracotta, - 3 volumes of fibrous constituent, - 3 volumes of cellulose wadding, - 4 volumes of water.

According to still other advantageous features of the invention, the straw is ground barley straw.

According to still other advantageous features of the invention, the composition comprises lime. According to still other advantageous features of the invention, the composition comprises cement, such as white cement.

According to still other advantageous features of the invention, the composition comprises the following proportions of additional ingredients, expressed in volumes: between 1 and 3 additional volumes of crushed terracotta, in particular 2 volumes, between 3/4 volume and 2 volumes of aerial lime, 25 - between 1/2 volume and 1 volume of cement.

According to still other advantageous features of the invention, the composition comprises the following proportions of additional ingredients, expressed in volumes: 30 - 2 additional volumes of crushed terracotta, - 1 volume of aerial lime, - 3/4 of volume of white cement.

The invention furthermore relates to a container, in particular a bag, containing a predetermined quantity of the composition above,

the exception of water, corresponding to a weight of between 20 and 60 kg, in particular 35 kg.

The invention further relates to a process for the preparation of a composition having all or some of the preceding characteristics and comprising the following steps: - supply of a quantity of water in a receptacle, - supply of a determined quantity of a mixture of: - raw clay sandy loam, - crushed terracotta, - fibrous constituent, chosen from: * straw such as ground barley straw, * wool residues, especially from waste from the textile industry cellulose wadding, addition of the mixture to the quantity of water, mixing.

According to still other advantageous features of the invention, the method comprises a step of conveying the composition inside a channel, from a receptacle for receiving the composition to an evacuation nozzle, in a which pressurized air is pulsed on the one hand near the discharge nozzle, and on the other hand upstream near the tank.

The invention also relates to a wall having a wood frame, comprising at least one face covered with a composition having all or part of the preceding characteristics.

According to other advantageous features of the invention, the thickness of the composition is, at least in a given zone, greater than 2 cm.

According to other advantageous features of the invention, the thickness of the composition is, at least in a given zone, greater than 3 cm.

The invention also relates to a machine for projecting a composition having all or some of the characteristics indicated above, the machine comprising a receiving tray of the composition, a channel for conveying the composition from the tray to a nozzle of evacuation, means for moving the composition inside the conveying channel, these means being provided with a worm whose rotation causes the displacement of the composition, the compressed air propulsion means of the composition , opening on the one hand close to the discharge nozzle to project the composition away from the nozzle, and on the other hand upstream of the discharge nozzle to facilitate the movement of the composition by pushing it inside the routing channel.

The spraying machine is a conventional machine marketed for example under the brand and reference "Putzmeister SP11" ©, on which it has adapted additional means of propulsion of compressed air, upstream of the outlet nozzle of the mixture. Other machines of the same type can also be used.

The invention will be better understood on reading the following description of a non-limiting embodiment of the invention and in the light of the appended FIG. 1 which diagrammatically represents a machine for projecting a composition according to the invention. invention, this machine being made from an adaptation of a conventional machine for example of the type "Putzmeister SP11" ©.

The invention relates above all to a composition intended to be applied as a mortar on a support or a wood frame. Basically, this composition consists of a mixture of: - raw clay sandy loam, - crushed terracotta, - at least one fibrous constituent selected from: * straw, including ground barley, * wool residues, - cellulose wadding, - water.

The raw earth consists of a clay mixture of about 20-25%, and sand. It is noted that a too high proportion of clay favors cracks and an excessive proportion of sand reduces the ability to stick. As a non-exhaustive example, the raw land of the Gard or the Cevennes is perfectly adapted to this use. Of course, the raw earth can come from other regions or parts of the world. The raw earth brings consistency and cohesion to the mix.

Clay helps to bind the mixture. However, it is specified that the water also acts as the main binder of the mixture, creating capillary bridges between the other components. It also allows good thermal insulation, due to a significant proportion of fibers. This fiber portion provides the thermal quality of the mixture. Earth, which is a material with a natural phase change, also brings thermal comfort due to its mass and its thermal inertia effect. It thus has a role of thermal and hygrometric regulation. The crushed terracotta is a load within the mixture whose function is to limit cracking. This makes it possible to homogenize the mixture and to prevent sticking in the machine to be sprayed. The terracotta which is of the same nature as the brick thus facilitates the flow of the mixture in the machine. In addition, crushed terracotta offers excellent water resistance in the presence of aerated lime.

The composition also comprises a fibrous component which is either in the form of ground barley straw or in the form of wool residues from the textile industry. It contributes essentially to thermal insulation, strength and mechanical reinforcement, especially in shear, tensile or tearing, friction.

The composition further comprises cellulose wadding. This material may advantageously be derived from recycled newspaper. Cellulose wadding is also uncompressed. This component enhances the insulating power of the composition and thus contributes to its sealing. It also limits crumbling and reduces shrinkage. -6 - 7

According to the invention, the composition comprises the following proportions of ingredients, expressed in volumes: between 5 and 7 volumes of sandy loam raw earth; for example, a proportion of 6 volumes of sandy clay soil is perfectly appropriate; - between 1 and 3 volumes of crushed terracotta; for example, a proportion of 2 volumes of crushed terracotta is perfectly suitable; between 2 and 4 volumes of fibrous constituent; for example, a proportion of 3 volumes of fibrous constituent is appropriate; - between 2 and 4 volumes of cellulose wadding; for example, a proportion of 3 volumes of cellulose wadding is adapted; - between 3 and 5 volumes of water; for example, a proportion of 4 volumes of water is suitable. The examples are given on a non-exhaustive basis.

The base composition obtained from the previous constituents applies to both internal and external walls or walls. However, it is anticipated that the composition will include additional ingredients or additional volumes of the base components, in the particular and non-exhaustive case of a mortar applied to exterior walls or walls. Of course, these additions can also be applied indoors. As additional volume, it is expected to add to the base composition between 1 and 3 additional volumes of crushed terracotta. A complement of 2 volumes of crushed terracotta is perfect.

An additional ingredient which is particularly appreciated for its sealing and water-resistance properties is also added to the base composition: lime, in particular aerial lime, is perfectly suitable. To this end, it is planned to add between 3/4 volume and 2 volumes of aerated lime. For example, it is possible to provide a volume of air lime. Cement, such as white cement, is added as another additional ingredient or component. An appropriate amount is, for example, 3/4 volume of cement. - 8

The invention further relates to a wall, a wall or a partition having a wood frame, comprises at least one face covered with a composition as described above.

Advantageously, the composition may have a thickness of at least 2 cm, and even greater than 3 cm, which is difficult to achieve with conventional coatings used with machines of the "Putzmeister SP11" © type. By way of example, it has been possible to achieve a thickness of at least 8 cm for such a composition applied to a vertical wall. Conversely, note also that the composition can be applied in thin thickness.

According to one particular aspect of the invention, the composition (basic or supplemented of the additional ingredients above) is advantageously presented and packaged in a bag, in particular a plastic bag, with the exception of the volumes of water indicated above which are added. at the time of final preparation of the mixture for application as a mortar using a machine or mechanized installation. Bags with a weight of the order of 35kg are suitable for transport and handling "man arm". We can also provide lower volumes, corresponding for example to a weight of 25kg.

At the site of the work site, the preparation of the final composition according to the invention therefore consists of a process in which: a quantity of water is supplied to a receptacle; a given quantity of a mixture of: raw sandy clay, - crushed terracotta, - fibrous constituent, chosen from: * straw such as ground barley straw, * wool residues, in particular from waste from the textile industry, - cellulose wadding, - the mixture is added to the quantity of water, - the whole thing is stirred. 2970475 -9

The method of the invention also provide that the delivery of the composition or mixture is from a receiving tray 1 (or supply) of the composition to a discharge nozzle 2. This method comprises a step in which pressurized air 3, 4 is pulsed on the one hand near the discharge nozzle by a first inlet 3 of compressed air, and on the other hand upstream of the discharge nozzle near the tank 1, by a second arrival 4 of compressed air.

According to an important aspect of the invention, a conventional spraying machine can be used with the composition or mixture according to the invention. Such a commercial machine is for example of the type "Putzmeister SP11" © classically used for the application of conventional coatings, or any machine with equivalent performance. In order to further improve the flow of the composition in the circuit of the machine, it is provided according to the invention to adapt a double inlet 3, 4 of compressed air in the circuit. Thus, one uses on the one hand the arrival of compressed air 3 originally provided near the outlet nozzle 2 of the mixture. On the other hand, a second inlet 4 of compressed air is provided, situated upstream of the first one, according to the direction of flow of the mixture. This second compressed air supply is for example located near the manometer originally provided at the outlet of the receiving tray. This second air intake can alternatively be connected to the circuit instead of the manometer.

Such a spraying machine comprises means for conveying the mixture from the receiving pan 1. These conveying means consist, for example, of a worm system 5 which pushes the mixture back into a duct 6 or opening circuit. at its opposite end on the discharge nozzle 2. It is noted that the stirring of the mixture can be carried out in the tank 1.

The additional arrival of compressed air (second arrival 4) aims to facilitate the flow of the mixture, to prevent the spinning of the mixture (which tends to occur under the continuous action of the worm which cups and 35 pushes downstream the consistent material: earth, fibers) and therefore to reduce 2970475 -10-

plug formation in the duct. The machine and the method of implementation described in this document are presented as non-exhaustive examples: other types of optimized machines (having a similar effect of reducing the spin and thus promoting the flow of the mixture) are also usable with the composition of the invention.

Of course, the invention is not limited to the means that have just been described and includes all the technical equivalents.

Claims (3)

REVENDICATIONS1. Composition intended to be applied as a mortar on a support or a wood frame, characterized in that it comprises a mixture of: - raw clay sandy loam, - crushed terracotta, - at least one fibrous constituent selected from: * straw, in particular ground barley, * wool residues, - cellulose wadding, - water. 2. Composition according to claim 1, characterized in that it comprises the following proportions of ingredients, expressed in volumes: - between 5 and 7 volumes of raw clay sandy loam, - between 1 and 3 volumes of crushed terracotta, - between 2 and 4 volumes of fibrous constituent, - between 2 and 4 volumes of cellulose wadding. - between 3 and 5 volumes of water. 3. Composition according to claim 1 or 2, characterized in that it comprises the following proportions of ingredients, expressed in volumes: - 6 volumes of raw clay sandy loam, - 2 volumes of crushed terracotta, - 3 volumes of constituent fibrous, - 3 volumes of cellulose wadding, - 4 volumes of water. 6. Composition according to any one of claims 1 to 3, characterized in that the straw is ground barley straw. 7. Composition according to any one of claims 1 to 4, characterized in that it comprises lime. 6. Composition according to any one of claims 1 to 5, characterized in that it comprises cement, such as white cement. 7. Composition according to claim 6, characterized in that it comprises the following proportions of additional ingredients, expressed in volumes: - between 1 and 3 additional volumes of crushed terracotta, in particular 2 volumes, - between 3/4 of volume and 2 volumes of aerial lime, - between 1/2 volume and 1 volume of cement. 10. Composition according to claim 6, characterized in that it comprises the following proportions of additional ingredients, expressed in volumes: - 2 additional volumes of crushed terracotta, - 1 volume of air lime, 15 - 3/4 of volume of white cement. 11. Container, in particular a bag, containing a predetermined quantity of the composition according to any one of the preceding claims, with the exception of water, corresponding to a weight of between 20 and 60 kg, in particular 35 kg. 12. Process for the preparation of a composition according to any one of the preceding claims, characterized in that it comprises the following steps: - supply of a quantity of water in a receptacle, - supply of a determined quantity of a mixture of: - raw clay sandy loam, - crushed terracotta, - fibrous constituent, chosen from: 30 * straw such as ground barley straw, * wool residues, especially from waste materials. textile industry, - cellulose wadding - addition of the mixture to the quantity of water, - brewing. 11. Wall having a wood frame, characterized in that it comprises at least one face covered with a composition according to any one of claims 1 to 8. 12. Wall according to claim 11, characterized in that that the thickness of the composition is, at least in a given zone, greater than 2 cm. 13. Wall according to claim 12, characterized in that the thickness of the composition is, at least in a given zone, greater than 3 cm.