WO2010018110A1

WO2010018110A1 - Method of producing at least one earth-based vertical wall

Info

Publication number: WO2010018110A1
Application number: PCT/EP2009/060147
Authority: WO
Inventors: Alain Leffebvre
Original assignee: Le Clos Les Perdrix
Priority date: 2008-08-12
Filing date: 2009-08-05
Publication date: 2010-02-18
Also published as: FR2935008B1; FR2935008A1

Abstract

The invention proposes a method of producing at least one earth-based vertical wall, comprising at least a first step of preparing a substantially vertical element (12, 18) of shuttering (10) determining the thickness of the wall to be produced, a second step of preparing an earthy material (22) and successively at least a third step of filling a cavity (20) of the element (12, 18) of shuttering (10) with the material, at least a fourth step of compacting the material, a fifth step of drying the material, and a sixth step of removing the shuttering (10), characterized in that, during the second step of preparing the material (22), a mixture comprising at least loamy soil, quick lime and cement is prepared in order to obtain said material.

Description

"Method of manufacturing at least one vertical wall made of earth"

The invention relates to a method for manufacturing at least one vertical wall made of earth. The invention relates more particularly to a method of manufacturing at least one vertical wall made of earth, comprising at least a first step of preparing a substantially vertical formwork element determining the thickness of the wall to be made, a second step of preparing an earthy material, and successively at least a third step of filling a cavity of the shuttering element with the material, at least a fourth step of compacting the material, a fifth drying step of the material and a sixth step of disassembly of the formwork. The construction of vertical earth-based walls has been known for a long time.

One of these types of construction, known as "rammed earth", is the use of compacted raw earth in formwork or bunching. The earth is thrown into the formwork in small layers of 0, 1 0 m to 1 m, or was compacted manually in the formwork with a pestle.

This type of construction makes it possible to obtain an earth-based wall that is sufficiently porous to allow ideal ventilation of the premises it delimits, but its use is limited at reduced heights due to the low resistance. compression of the material used. It is therefore not possible with this method to raise high walls.

Moreover, the "rammed earth" is by its porosity very sensitive to erosion and therefore offers only a limit rite in time. The invention overcomes this disadvantage by proposing a new construction method implementing a new material for the construction of high walls likely to have a long service life. For this purpose, the invention proposes a process of the type described above, characterized in that during the second step of preparation of the material, a mixture is prepared comprising at least earth imon, quicklime, and cement, to get it's material.

According to other features of the invention:

during the second step of preparation of the material, a mixture is prepared comprising at least earth imon, quicklime, cement and fibers, the fibers comprise synthetic fibers, in particular polypropylene,

the fibers comprise natural fibers, in particular Mn or cotton,

the mixture comprises a volume proportion of substantially 2% to 3% of quicklime and 3% to 15% of cement,

the mixture comprises a proportion of fibers of substantially 2 to 1 2 kg per m ³ of mixture,

the mixture is prepared at a humidity level of 25 to 35%, to allow air to replace the water of the mixture during its evaporation, in order to confer a high thermal insulation capacity on the material once said material is dry,

the method comprises at least one succession of series of steps, each of which comprises at least the first, third and fourth stages, to allow the wall to be mounted by successive filling and compacting of the material in stacking elements stackable on each other; other,

- the land of the imon is a land of fine clayey silt,

- The earth imon is a clay loam soil charged with pebbles, - during the second stage of preparation of the material, the mixture is realisé using a kneader, including a mobile kneader allowing the real isation of the mixture on the same site where the wall must be made, the method comprises an additional step, interposed between the first and third steps, during which there is introduced into the shuttering element at least one load-reinforcing element of the wall, - the load-reinforcing element is constituted a truss reinforcement is welded,

the fourth step of compaction of the material is carried out at least with the aid of a manual or pneumatic pestle,

the fourth step of compaction of the material is carried out at least with the aid of vibrating pins.

The invention also relates to a formwork for implementing the method according to the invention characterized in that it comprises a stack of formwork elements each comprising at least one inner vertical wall element, maintained by at least one structure strut, and an outer wall member, delimiting between them a cavity, at least the outer vertical formwork elements being added successively to each other as the wall rises. Other characteristics and advantages of the invention will become apparent from reading the detailed description which it is known for the understanding of which reference will be made to the appended drawings in which:

- Figure 1 shows a third step of the method of the invention implemented using the formwork according to the invention;

FIG. 2 represents a first embodiment of the fourth step of the method of the invention;

FIG. 3 represents a new third step of the method according to the invention; FIG. 4 represents the sixth step of the method according to the invention. In the following description, like reference numerals designate like parts or having similar functions.

There is shown in the figures the implementation of a method of manufacturing a vertical wall-based earth according to the invention.

In known manner, such a method comprises at least a first step of preparing a substantially vertical formwork element determining the thickness of the wall to be made, a second step of preparing an earthy material, and successively at least a third step filling the shuttering element with the material, at least a fourth step of compacting the material, a fifth step of drying the material and a sixth step of disassembling the formwork.

A method of this type is commonly used in the manufacture of concrete walls, or more traditionally for the manufacture of "rammed" walls.

However, one of the disadvantages of concrete walls is the difficulty of their implementation on light construction sites, the concrete to be prepared beforehand and brought to the site.

Furthermore, once cast and hardened, the concrete can be difficult to work, which makes it unsuitable for example to build a particular house in which must be arranged a large number of openings.

The construction in "rammed earth", that is to say in clay simply compacted, is easier to implement, but rammed earth is not likely to allow the construction of walls of high height, and offers as well as a poor resistance to moisture.

The process which is the subject of the invention is therefore innovative in that, according to a first embodiment of the process, during the second stage of preparation of the material, prepare a mixture containing at least silt soil, quicklime, and cement to obtain this material.

The material thus obtained has the advantages of traditional rammed earth, since the imon earth base which is used allows a good breathing of the material, which also has high characteristics of thermal and acoustic insulation.

The material thus obtained is however much more resistant than ordinary clay, because the presence of quicklime makes it possible to absorb the hum idity of the material and because the cement makes it possible to reinforce the cohesion of the material.

In the preferred embodiment of the invention, the mixture comprises a volume proportion of substantially 2% to 3% of quicklime and 3% to 15% cement.

According to a second variant embodiment of the process forming the subject of the invention, during the second step of preparation of the material, a mixture is prepared comprising not only at least the earth of the imon, lime live, and cement, but also fiber.

The fibers can be of different types. According to a first variant of this second embodiment, the fibers comprise synthetic fibers, in particular polypropylene fibers.

According to a second variant of this second embodiment, the fibers comprise natural fibers, especially Mn or cotton.

Whatever the mode of execution of the process, whether or not the mixture is provided with fibers, it will be preferable to use a commercially available cement which is commercially available under the reference PORTLAN D CPJ 45. This composition makes it possible to to obtain a material offering a compressive strength of about 20 to 30 M Pa, which, unlike conventional clay, makes it possible to produce walls several meters high in a single application of the process. Preferably, the selected land will be a clay loam soil, available in almost all building zones.

Depending on the consistency and resistance that will be given to the wall to be obtained, we will choose a fine clay loam soil, or a clay loam soil laden with pebbles.

The advantage of this material is that it can be prepared on the site where the wall is to be built. Thus, during the second step of preparation of the material, the mixing is carried out using a kneader, in particular a mobile kneader carried in known manner by a tractor-type construction machine (not shown).

In the more specific case of the second embodiment of the process, the mixture preferably comprises a proportion of fibers of substantially 2 to 12 kg per m ³ of mixture, in addition of 2% to 3% of quicklime and 3% 15% cement mentioned above.

Another particularly advantageous characteristic of the process which is the subject of the invention is that, whatever its mode of execution, during the second stage of preparation of the material, the mixture is prepared according to a moisture content of 25 to

35%.

This configuration allows the ambient air, as the material dries and the water it contains evaporates, to replace the water of the mixture. In this way, the air contained in the material imparts to said material, once dry, a high thermal insulation capacity.

Furthermore, the manufacturing method preferably comprises at least a succession of series of steps, each of which comprises at least the first, third and fourth stages, to enable the wall to be mounted by successive filling and compacting of the material in formwork elements. stackable on top of each other. For this purpose, as illustrated more particularly in FIGS. 1 and 3, on a floor or slab 1 1, the formwork 1 0 comprises, in accordance with the invention, a stack of formwork elements each comprising at least one element 12. of inner vertical wall, maintained by at least one strut structure 14, and an outer vertical wall element 1 8, at least the outer vertical formwork elements 18 being added successively to one another as and when the rise of the wall, that is to say during the third successive stages. As illustrated in Figure 1, it is possible to set up before all the elements 1 2 of the inner vertical wall, then successively the outer vertical formwork elements 18. This allows to set up only a forestay structure 14, is in place from the beginning of the operation. Alternatively (not shown), it is possible to successively install in pairs the inner vertical wall elements 12 and outer vertical formwork elements 1 8, but this requires to modify the strut structure 14 as and when Measurement of the stack of elements 1 2. The elements 1 2 of inner vertical wall thus form an inner wall 15 and the outer vertical formwork elements 18 thus form an inner wall 1 6.

The walls 1 5 and 1 6 therefore delimit between them a cavity 20. Preferably, the formwork 1 0 is realisé in a first step during which the wall 1 5 is put in place in its totality and a vertical formwork element 1 8. If the mixture is prepared during the second stage.

As illustrated in FIG. 1, which represents a third inital step of the process of the invention, the material 22 is then introduced into the cavity 20.

As is illustrated in FIG. 2, during a fourth process step, the material 22 is compacted. According to a first embodiment of this fourth step, the compaction of the material 22 is realisé using a pestle 24.

As illustrated in Figure 2, the pestle 24 may be manual, but alternatively (not shown), this pestle 24 could be pneumatic.

According to a second embodiment of the fourth step of the method (not shown), the compaction of the material 22 is real ized with the help of vibrating pins. These needles are of the type that are commonly encountered on construction sites to achieve the vibration of concrete.

Of course, it will be understood that, alternatively, (not shown), the compacting of the material can be carried out according to a combination of these two variants, that is to say both with the aid of a pestle and sharp vibrating illes.

If the wall obtained is high enough, then we move to a fifth step during which the material is allowed to dry, or to a sixth step during which we remove the formwork 10. If the wall is not enough at the end of the fourth compaction step, an external vertical element 18 is added during a new first step of preparing the formwork 10.

Each element 18 can be fixed to the previous one by means of fasteners 30.

Then, the cavity 20 of material 22 is filled again with a new third step, and then this material 22 is compacted again by means of the pestle 24.

The operation is then repeated until the desired wall height is obtained.

From a given height, can be added to the formwork 10 a bridge 26 to circulate in height along the wall and perform the fourth compaction steps. It will be noted that the method could comprise an additional step, interposed between the first and third steps, during which is introduced into the formwork element 10, that is to say in the cavity 20 at least one reinforcing element load of the wall (not shown).

This load reinforcing element could consist of a welded mesh reinforcement similar to those used in pouring reinforced concrete.

The invention thus makes it possible to erect high earth-based walls, for example walls three meters high and more, intended for individual dwellings, in a single "spoiled", that is to say in one application of the process.

The walls thus obtained have high qualities of resistance while allowing a certain ventilation of the dwellings, by their breathable and insulating qualities.

Moreover, the method that is the subject of the invention makes it possible to raise such walls extremely quickly, the material being able to be manufactured on the site of the construction site, which makes it possible to considerably lower the manufacturing costs of a dwelling. individual or a work of another type.

Claims

1. A method of manufacturing at least one vertical earth-based wall, comprising at least a first step of preparing a substantially vertical formwork element (12, 18) determining the thickness of the wall to be produced, a second step of preparing an earth material (22), and successively at least a third step of filling a cavity (20) of the shuttering element (12, 18) with the material, at least a fourth compaction step of the material, a fifth step of drying the material and a sixth step of disassembly of the formwork (10), characterized in that during the second step of preparing the material (22), a mixture is prepared comprising less of silt soil, quicklime, and cement, to obtain said material.

2. Manufacturing process according to the preceding claim, characterized in that during the second step of preparation of the material (22), is prepared a mixture comprising at least of silt soil, quicklime, cement and fibers.

3. Manufacturing process according to the preceding claim, characterized in that the fibers comprise synthetic fibers, in particular polypropylene.

4. Manufacturing process according to claim 2, characterized in that the fibers comprise natural fibers, especially Mn or cotton.

5. Manufacturing process according to claim 1, characterized in that the mixture comprises a volume proportion of substantially 2% to 3% of quicklime and 3% to 15% of cement.

6. Manufacturing process according to the preceding claim taken in combination with one of claims 2 at 4, characterized in that the mixture comprises a proportion of fibers of substantially 2 to 12 kg per m ³ of mixture,

7. Manufacturing process according to any one of claims 5 or 6, characterized in that the mixture is prepared at a moisture content of 25 to 35%, to allow air to replace the water of the mixture during its evaporation, in order to confer a high thermal insulation capacity to the material once said material is dry.

8. Manufacturing method according to one of the preceding claims, characterized in that it comprises at least one succession of series of steps each of which comprises at least the first, third and fourth stages, to allow to mount the wall by fills and sequentially compacting the material (22) into stackable elements (12, 18) stackable (10) on top of one another.

9. Manufacturing process according to one of the preceding claims, characterized in that the silt land is a fine clay loam soil.

10. Manufacturing process according to one of claims 1 to 8, characterized in that the silt land is a clay loam soil loaded with pebbles.

1 1. Production method according to one of the preceding claims, characterized in that during the second step of preparing the material (22), the mixing is carried out using a kneader, in particular a mobile kneader allowing the realization mixing on the same site where the wall is to be made.

12. Manufacturing method according to one of the preceding claims, characterized in that it comprises an additional step, interposed between the first and third steps, during which is introduced into the element (12, 18) formwork ( 10) at least one load-reinforcing element of the wall.

13. Manufacturing process according to the preceding claim, characterized in that the load-reinforcing element consists of a welded mesh reinforcement.

14. The manufacturing method according to one of the preceding claims, characterized in that the fourth compaction step of the material is carried out at least with the aid of a pestle (24) manual or pneumatic.

15. The manufacturing method according to one of claims 1 to 13, characterized in that the fourth compaction step of the material is carried out at least using vibrating needles.

Formwork for the implementation of a method according to claim 8, characterized in that it comprises a stack of shuttering elements (12, 18) each comprising at least one inner vertical wall element (12) ( 15), held by at least one strut structure (14), and an outer wall element (18) defining between them a cavity (20), at least the outer vertical formwork elements (18) being added successively to each other as the wall rises.