Machine for spraying earth-based mortar

Abstract

The present invention relates to a method for spraying an earth-based mortar with a spraying machine where the sparrow pump does not have a jacket for spraying single-layer coating (e.g. type 2L6 or 2R6) but a jacket for liquid screed (e.g. type 60 / 12 or T25) or traditional mortar (e.g. 2L7); the pipework, if it is less than 10 meters long, has an internal diameter of approximately 35 mm or, if it is longer than 10 meters, an internal diameter of approximately 50 mm at the sparrow pump outlet and an internal diameter of approximately 35 mm over its last 10 meters; the body of the spraying lance has an internal diameter of approximately 35 mm with a nozzle having a diameter of between 16 and 22 mm; and a compressed air line opens at the end of the nozzle to allow the earth-based mortar to be sprayed onto the surface.

Description

Title of the invention: Machine for projecting earth-based mortar Field of invention

[0001] The present invention relates to a method of spraying an earth-based mortar. State of the art

[0002] As part of regulatory developments, it is now mandatory in the construction sector to take into account the environmental impact of the materials used. Also, we are witnessing a considerable evolution in construction techniques with the use of new, more environmentally friendly materials. However, and to allow for wide dissemination, any new technology must, in addition to benefiting from good performance, be simple to implement and also inexpensive.

[0003] This demand is still far from being satisfied today and the demand for new technologies more suited to building professionals is still strongly felt.

[0004] In the building industry, the coating of masonry work with premixed coatings has long been used, which are diluted from a powdered product directly at the time of their application by spraying onto the masonry work. Such coatings have a relatively rapid solidification capacity, these having a mainly gaseous base with more or less additives to improve their qualities. Such mechanical application of coatings on walls is particularly advantageous because it allows the manual work of masons to be considerably reduced. This advantage has allowed a very wide distribution of these coating projection machines which are capable of mixing, pumping and then projecting the coating onto a surface of a building. Summary of the invention

[0005] The inventors have developed a new material capable of replacing concrete corresponding to an earth-based mortar. In addition to its mechanical and thermal properties, this material has the advantage of being able to be projected onto a vertical surface, which facilitates its implementation and therefore reduces the associated costs.

[0006] The inventors have now been able to spray this earth-based mortar using conventional plaster spraying machines with some modifications to these machines.

[0007] Consequently, a first object of the invention is a method of spraying an earth-based mortar with a spraying machine, which method comprises the steps of:

[0008] i) preparation of the earth-based mortar by mixing:

[0009] ia) earth from earthworks or excavation operations (quarry), or crushed deconstruction materials (concrete, brick, plaster, stone, and mortar), excluding topsoil, with a grain size less than or equal to 20 mm, preferably less than or equal to 15 mm, in a volume proportion of 20 to 55%, preferably 25 to 50% and, particularly preferably, 20 to 40%;

[0010] ib) a binder comprising slag or metakaolin and, optionally, lime, in a volume proportion of 15 to 55%, preferably 25 to 50%;

[0011] ic) aggregates with a particle size of between 2 and 20 mm, and in a volume proportion of 0 to 20%;

[0012] id) fibers in a volume proportion of between 0 and 30%, preferably between 10 and 30% and, particularly preferably, between 10 and 20%;

[0013] ie) of the crystallizer in a volume proportion of between 0.1 and 15%, for example between 0.3 and 10% or even between 1 and 8%, preferably between 1 and 4%; and particularly preferably between 2 and 4%; and

[0014] if) water in a volume proportion of between 5 and 20%, preferably between 5 and 10%.

[0015] ii) pouring the mixture, at the end of step i), into a loading hopper which is fixed to the frame of the spraying machine,

[0016] iii) pumping the mixture through an orifice of this same loading hopper, by a sparrow pump and injection of this mixture into a pipe extending said pump; and

[0017] iv) projection, towards a surface, of the mixture at the end of the pipe by a lance terminating in a nozzle, preferably a vertical surface

[0018] where:

[0019] - the sparrow pump does not have a jacket for spraying mo coating no-layer (e.g. type 2L6 or 2R6) but a jacket for liquid screed (e.g. type 60 / 12 or T25) or traditional mortar type (e.g. 2L7);

[0020] - the piping, if it has a length of less than 10 meters, has a internal diameter of approximately 35 mm or, if it is longer than 10 metres, an internal diameter of approximately 50 mm at the sparrow pump outlet and an internal diameter of approximately 35 mm over its last 10 metres;

[0021] - a projection lance body with an internal diameter of approximately 35 mm with a nozzle with a diameter between 16 and 22 mm

[0022] - a compressed air line opening at the end of the nozzle to allow the projection of the earth-based mortar onto the surface.

[0023] Advantageously, the mixing step i) is carried out in a mixing container of the spraying machine, which mixing container is capable of pivoting around a horizontal tilting axis around the frame so as to allow the mixture to be poured into the loading hopper.

[0024] Advantageously, the method according to the invention makes it possible to spray up to 14m3 of earth-based mortar per day.

[0025] Advantageously also, step iii) of pumping the mixture through an orifice of this same loading hopper, by a sparrow pump and injection of this mixture into a pipe extending said pump is carried out at a pressure of between 8 and 18 bars, preferably between 10 and 12 bars (1 bar = 0.1 MPa).

[0026] A second subject relates to a machine which comprises a loading hopper which is fixed to the frame of the spraying machine, a sparrow pump connected to an orifice of this same hopper and which allows the pumping and injection of the mixture into a pipe extending said pump; and at the end of the pipe, a lance ending in a nozzle, characterized in that:

[0027] - the sparrow pump does not have a jacket for spraying mo coating no-layer (e.g. type 2L6 or 2R6) but a jacket for liquid screed (e.g. type 60 / 12 or T25 or 2L7);

[0028] - the piping, if it has a length of less than 10 meters, has a internal diameter of approximately 35 mm or, if it is longer than 10 metres, an internal diameter of approximately 50 mm at the sparrow pump outlet and an internal diameter of approximately 35 mm over its last 10 metres;

[0029] - a projection lance body with an internal diameter of approximately 35 mm with a nozzle with a diameter between 16 and 22 mm

[0030] - a compressed air line opening at the end of the nozzle to allow the projection of the earth-based mortar onto the surface.

[0031] A third object of the invention relates to the use of such a machine for implementing a method as described above.

[0032] A fourth object relates to a kit for a projection machine comprising:

[0033] - a jacket for liquid screed (e.g. type 60 / 12 or T25) or for tra mortar additional (ex.2L7);

[0034] - a projection lance body with an internal diameter of approximately 35 mm with a nozzle with a diameter between 16 and 22 mm

[0035] - a compressed air line opening at the end of the nozzle to allow the projection of the earth-based mortar onto the surface;

[0036] - Possibly a pipe, if it has a length of less than 10 meters, has an internal diameter of approximately 35 mm or, if it is longer than 10 metres, an internal diameter of approximately 50 mm at the sparrow pump outlet and an internal diameter of approximately 35 mm over its last 10 metres;

[0037] A fifth object relates to the use of such a kit for implementing a method as described above from a projection machine, preferably a facade projection machine (i.e. a machine dedicated to the projection of single-layer coatings). Detailed description of the invention

[0038] A sparrow pump is a pump consisting of a helical rotor rotating inside a helical stator. The rotor, generally made of stainless steel, is machined with great precision, while the stator, called the jacket, is molded from an abrasion-resistant elastomer.

[0039] The geometry and dimensions of these parts are such that when the rotor is inserted into the stator, a double chain of sealed alveoli cavities is formed. When the rotor rotates inside the stator, the alveoli progress along the axis of the pump, describing a spiral without changing shape or volume, thus transferring the product from the suction inlet to the discharge outlet.

[0040] The universally used facade spraying machines are eccentric screw pumps with a jacket for spraying single-layer coating of type 2L6 or 2R6 which are found on machines of type S5, SP5, SP11 from PUTZMEISTER, S8, S28R, S38 from BUNKER, PH9B or PH9B-R from LANCY, Talent DMR from TURBOSOL.

[0041] The volume proportion of each component corresponds to the volume occupied by this component in relation to the total volume of the mortar mixture.

[0042] Mortar means both a coating, which can be applied to a surface and has a strength of at least 5 MPa, a mounting or filling mortar with a strength of at least 10 MPa, and a mortar intended for the manufacture of a load-bearing wall with a strength of at least 15 MPa.

[0043] The method according to the invention can therefore allow the creation of both a coating and a wall.

[0044] Advantageously, the mortar prepared by the process according to the invention comprises cement in a volume proportion of less than or equal to 5%, preferably less than or equal to 1% and, particularly preferably, a volume proportion of less than 0.5% of cement, or even 0% of cement.

[0045] The environmental impact of the process according to the invention is therefore much less than that of existing processes which generally use at least 10% cement.

[0046] By earth is meant earth resulting from earthworks or excavation operations (quarry), or even crushed deconstruction materials (excluding topsoil).

[0047] By deconstruction material we mean concrete, plaster, stone or even mortar.

[0048] Advantageously, the earth is chosen from the group comprising earth resulting from earthworks or excavation operations (quarry).

[0049] This earth may therefore present a very great diversity of nature depending on the site from which it comes. It will thus be possible to find earths incorporating gypsum, silt, limestone, silica, clay or even their mixture. Preferably, said earth will incorporate a clay content less than or equal to 50% by weight, preferably less than or equal to 25% and, particularly preferably, less than or equal to 10%. Such a content can be determined by a granulometric method such as that described in standard NF X31-107.

[0050] Now, the earth does not come from sand quarries or aggregate quarries (virgin aggregates).

[0051] Furthermore, it will be preferred to use earth that has undergone at most one pretreatment by grinding, sorting (e.g. according to the color), sieving and / or drying before being mixed with the other components of the earth mortar. Now, the earth used in the mortar according to the invention has not undergone any sorting or sieving step so as to eliminate elements having a dimension between 10 and 20 mm, preferably between 10 and 15 mm. It should be noted that the earth used has therefore not undergone any chemical pretreatment, such as pretreatment with a surfactant, so as to modify its structure and allow it to liquefy.

[0052] Prior to using earth, care should be taken to determine the presence or absence of traces of metallic elements (Pb, As, etc.) so as to prevent any contamination.

[0053] Advantageously, the earth used in the method according to the invention will have a particle size less than or equal to 10 mm, preferably less than or equal to 6 mm.

[0054] Obtaining soil of a desired particle size from such a variety of sources will generally require, in addition to determining the particle size of the soil, a sieving operation.

[0055] According to a preferred embodiment, the method according to the invention will therefore preferably comprise a step of sieving the earth prior to step i).

[0056] The very high adaptability of the method according to the invention to the different types of existing earth allows it to use the earth itself from the site on which the method is implemented.

[0057] According to another preferred embodiment, the method according to the invention will preferably comprise a step prior to step i) of extracting the earth and, optionally, sieving it.

[0058] Slag is understood to mean the slag formed during the melting or production of metal by liquid means. It is a mixture composed essentially of silicates, aluminates and lime with various metal oxides with the exception of oxides of iron.

[0059] The slag will preferably be used in a volume proportion of between 10 and 40%, preferably between 10 and 30%.

[0060] By metakaolin is meant the product of a calcination of kaolin and / or kaolinic clay.

[0061] Preferably, the binder comprises slag and, optionally, lime.

[0062] The lime will preferably be used in a volume proportion of between 0 and 25%, preferably between 1 and 25%, for example between 5 and 20%, and particularly preferably between 10 and 20%.

[0063] Lime means artificial lime which essentially comprises calcium and magnesium oxide and / or calcium and magnesium hydroxide.

[0064] Advantageously, the lime is chosen from the group comprising hydraulic lime and air lime.

[0065] Preferably, hydraulic lime will be used, which preferably does not include cement.

[0066] Preferably, a hydraulic lime NHL 3.5 or NHL 5 will be used.

[0067] Preferably, the use of NHL 3.5 Z or NHL 5 Z hydraulic lime will be avoided, since it includes cement.

[0068] Aggregates include both natural aggregates (e.g. gravel or sand) and recycled aggregates (e.g. crushed concrete or mortar).

[0069] Now it is possible to mix different types of aggregates, natural and recycled, in varying proportions.

[0070] As regards the particle size, a particle size of between 4 and 10 mm will be preferred and, in a particularly preferred manner, a particle size of between 4 and 6 mm.

[0071] As with earth, it is possible to use aggregates from all or part of the site on which the process is implemented.

[0072] In the case where the earth used includes aggregates. Then the proportion of aggregates added in addition to the earth is adapted so that the total volume proportion of aggregates is between 0 and 20%, preferably between 5 and 20% and particularly preferably between 10 and 20%.

[0073] According to yet another preferred embodiment, the method according to the invention will preferably comprise a step prior to step i) of extracting aggregates and, optionally, sieving them.

[0074] By crystallizer, sometimes also called mineralizer, we mean compounds capable of forming, by a reaction called mineralization, crystalline and insoluble complexes with the soluble compounds of the mortar (free lime).

[0075] Examples of such compounds that may be mentioned include, for example, silicate salts, carbonate salts (e.g. natron), alginate salts.

[0076] According to a particular embodiment, the crystallizer comprises at least one strong base in proportion such that the pH of the mixture at the end of step i) is equal to or greater than 9.0, preferably greater than or equal to 10.0 and, particularly preferably, greater than or equal to 11.0. As a base, mention may be made of sodium or calcium hydroxide.

[0077] Such crystallizers are known for use in waterproofing concrete, in particular under the names PENETRON, XYPEX, VANDEX, mineralizing B HYDRO-MINERAL, etc.

[0078] Preferably, the crystallizer comprises silicate ions capable of forming silicate complexes with calcium hydroxide, in particular calcium, magnesium, sodium or potassium silicate.

[0079] Preferably, calcium and / or magnesium silicate will be used.

[0080] Depending on the silicate salt, it will be possible to add a strong base or not.

[0081] Thus, if the use of sodium silicate does not involve using an additional base, sodium or calcium hydroxide can be added in the case of a crystallizer comprising calcium and / or magnesium silicate.

[0082] According to a preferred embodiment of the method according to the invention, step ie) is carried out simultaneously or consecutively to step ib), preferably simultaneously.

[0083] By fibers is meant both synthetic fibers (e.g. polypropylene fibers, glass fibers, carbon fibers, etc.) and natural fibers (e.g. hemp), which fibers can be in any form (elongated or circular), preferably in an elongated form.

[0084] Advantageously, the fibers used are solid fibers, that is to say they have a structure devoid of cavities.

[0085] Typically, the fibers used have a length of between 5 and 100 mm, preferably between 5 and 70 mm and, particularly preferably, between 10 and 50 mm.

[0086] According to a preferred embodiment, natural fibers or plant fibers will be used. To obtain such plant fibers, fiber plants, a large part of which are well known, may be used.

[0087] For bast fibers, corresponding to bark fiber, we can cite as examples hemp, jute, kenaf, barrel vine, linen, nettle, papyrus, esparto, linden fibers, bamboo fibers, Provence cane fibers, sea rush, miscanthus fibers, bagasse, etc.

[0088] For leaf fibers, we can cite Manila hemp (from abaca), pina (from pineapple), agave leaf fiber (e.g. sisal).

[0089] For fibers from seeds or fruit, we can cite coir, rice husk or straw or even cotton.

[0090] Finally, the mortar may incorporate other adjuvants such as plasticizing agents, water-retaining agents, water-repellent agents, biocides, fungicides, dispersants, air entrainers (chasers), setting accelerators, setting retarders, fluidifiers, antifreeze agents or even expansion agents.

[0091] Naturally, each of these adjuvants can be added to the mortar alone or in combination with one or more other adjuvants.

[0092] Step i) of mixing can be carried out according to techniques well known to those skilled in the art.

[0093] Advantageously, the mixing is carried out using a mixer, in particular a mobile mixer with horizontal or vertical axes allowing the mixing to be carried out on the very site where the wall is to be built.

[0094] If the earth-based mortar cannot be used immediately after step i), it is also possible, by omitting to add at least the water, to bag the mixture during step i) for its transport and / or storage before being finalized prior to its use in step ii) of the process according to the invention.

[0095] Step ii) of pumping can be carried out according to techniques well known to those skilled in the art.

[0096] This pumping step is carried out using a pumping means such as a piston pump or a worm pump.

[0097] Advantageously, the mixture is heated to a temperature greater than or equal to 40°C, preferably greater than or equal to 45°C during this pumping step so as to allow rapid setting of the mortar, especially in the case of projection onto a vertical surface.

[0098] Such a temperature may possibly be obtained by the sole friction of the mixture obtained at the end of step i) with the surfaces of the device allowing pumping (e.g. friction of the mixture with the surface of the worm screw).

[0099] According to a particular embodiment of the method according to the invention, it is intended for injection into a mold for a construction element.

[0100] Indeed, the specificities of the mortar obtained allow its industrial use in the manufacture of construction elements such as borders, concrete blocks, paving stones, etc.

[0101] By mold of at least one construction element, we mean a mold chosen from the group comprising molds for concrete blocks, hollow or solid, borders, paving stones and slabs.

[0102] In this case, the method according to the invention may further comprise the step of:

[0103] iv) compression of the injected mixture into a mold for at least one construction element.

[0104] This compression step is carried out by devices well known to those skilled in the art.

[0105] If necessary, this step can be followed or preceded by a step of stirring the mixture in the mold to limit the presence of bubbles.

[0106] Also, the method according to the invention may further comprise the step of:

[0107] v) stirring the mixture in the mold.

[0108] This stirring step can be carried out by means of vibrating devices positioned in the mold or associated with it. Examples include vibrating tables or vibrating probes (needles).

[0109] This step may be followed by a step vi) of drying and demolding.

[0110] According to another particular embodiment of the method according to the invention, the latter is intended for projection onto a horizontal or vertical surface, preferably onto a vertical surface.

[0111] Indeed, and surprisingly, the characteristics of the earth-based mortar according to the invention, and in particular its rapid setting, allow it to be projected onto a vertical surface in layers of around ten centimeters and without observing any sagging. It is also possible to carry out successive applications of the mortar according to the invention by applying a covering time of between 30 minutes and 6 hours between two successive layers, preferably between 1 and 3 hours.

[0112] Advantageously, the method according to the invention allows the production of a thickness of earth-based mortar of up to 50 cm, preferably up to 25 cm. It should be noted that this thickness can be produced by means of one or more applications of the mortar on the surface. Typically, each application will increase the thickness by at most 10 cm.

[0113] Now and preferably, the surface onto which the earth-based mortar is projected comprises a reinforcing element, which can for example take the form of a reinforcement, which reinforcement can be metallic, plastic (polyethylene, polypropylene, etc.) or plant-based (bamboo, Provence cane, etc.).

[0114] As for the projection as such, it is carried out by means of devices well known to those skilled in the art. Typically, such projection is carried out by means of a projection lance placed at the outlet of the pumping means.

[0115] Such a projection lance takes the form of a flexible pipe of suitable cross-section at the end of which is positioned a projection nozzle. Typically, such a projection lance further incorporates an air inlet slightly upstream of the nozzle, which air inlet contributes to the projection of the earth-based mortar and to the entrainment of said earth-based mortar with a view to its projection onto a surface. vertical or horizontal.

[0116] A second object of the invention relates to the earth-based mortar as obtained at the end of step i) of the method described above.

[0117] Such a mortar according to comprises:

[0118] a) an earth with a particle size less than or equal to 20 mm, preferably less than or equal to 15 mm in a volume proportion of 20 to 55%, preferably 20 to 40%;

[0119] b) a binder comprising slag or metakaolin and, optionally, lime, in a volume proportion of 15 to 55%, preferably 25 to 50%;

[0120] c) aggregates with a particle size of between 2 and 20 mm, preferably between 2 and 15 mm, and in a volume proportion of 0 to 20%;

[0121] d) fibers in a volume proportion of between 0 and 30%, preferably between 10 and 30%, and particularly preferably between 10 and 20%;

[0122] e) of the crystallizer in a volume proportion of between 1 and 15%, for example between 1 and 8%, preferably between 1 and 4% and, particularly preferably, between 2 and 4%; and

[0123] f) optionally water in a volume proportion of between 5 and 20%, preferably between 5 and 10%.

[0124] The characteristics and proportions of each component of the mortar are as described above.

[0125] Advantageously, the mortar according to the invention is packaged in a bag and does not contain water.

[0126] A third subject of the invention relates to a mixture intended for the preparation of a mortar according to the invention, which mixture comprises:

[0127] a) between 90 and 98% by weight of a binder (relative to the total weight of the mixture) comprising slag or metakaolin and, optionally, lime,

[0128] b) between 2 and 10% by weight, preferably between 3 and 8%, by weight of crystallizer (relative to the total weight of the mixture), preferably between 4 and 6%.

[0129] Preferably, this mixture does not include earth, aggregates or plant fibers which are intended to be added on site to make the earth-based mortar.

[0130] Advantageously, the binder comprises slag and, optionally, lime.

[0131] The mixture will further comprise between 0 and 50% lime.

[0132] Accordingly, a preferred mixture comprises:

[0133] al) between 30 and 90% by weight of slag (relative to the total weight of the mixture), preferably between 50 and 85% and, particularly preferably, between 60 and 80%, typically between 70 and 77%,

[0134] a2) between 3 and 40% by weight of lime (relative to the total weight of the mixture), of preferably between 5 and 20% and, particularly preferably, between 10 and 20%.

[0135] b) between 2 and 10% by weight of crystallizer (relative to the total weight of the mixture), preferably between 3 and 8% and, particularly preferably, between 4 and 6%.

[0136] Preferably, the crystallizer comprises silicate salts, preferably chosen from the group comprising calcium, magnesium, sodium and potassium silicate.

[0137] Optionally, the crystallizer further comprises a base, preferably sodium or calcium hydroxide.

[0138] Advantageously, the mixture according to the invention is packaged in a bag and does not include water.

[0139] A fourth object of the invention relates to a construction element capable of being obtained using a mortar as defined previously.

[0140] Such a product can take the form of any construction element, whether concrete block (solid or hollow), curbs, paving stones and slabs.

[0141] A fifth object of the invention relates to the use of a mortar or a mixture as described above for the production of earth-based construction elements.

[0142] By construction elements we mean partitions, blocks, concrete blocks (hollow or solid), borders, paving stones, slabs, etc.

[0143] By production, we mean production by injection or projection.

[0144] Other characteristics, details and advantages of the invention will emerge more clearly from the detailed description given below for information purposes.

[0145] Preparation of the spraying machine:

[0146] The spraying machine is adapted as follows:

[0147] 1 / Change of the standard single-layer projection jacket (2L6) by a liquid screed jacket (60 / 12 or T 25) more or less long depending on the desired projection flow rate jacket reference or 217 or equivalent)

[0148] 2 / Installation of a 50 diameter pipe for the first lengths and reduction in diameter 35 for the last 10 meters if the line is greater than 10 meters. Otherwise, installation of a 50 / 35 reducer at the exit of the machine cone with a 35 mm line.

[0149] 3 / Installation of an air line connected to the machine's compressor with a T and two valves allowing the control and adjustment of the air flow in order to regulate the projection of the mortar

[0150] 4 / Installation of a projection lance body with an internal diameter of 35 mm with a nozzle diameter of 16 to 22 mm depending on the projection

[0151] Process for preparing earth mortar

[0152] The site soil is sieved with 10 mm mesh.

[0153] The sieved site soil is then incorporated into the mixer tank of a TURBOSOL T20X spraying machine. 4 / 6 gravel, hemp fibers (10 mm) and a rapid mixing of the mixture is carried out for a few minutes (usually around 2 minutes). Water is then incorporated into the mixture and the rapid mixing allows the mixture to be homogenized. Finally, the binder and the crystallizer are incorporated into the mixture and a longer mixing stage is carried out (typically between 3 and 5 minutes) in order to obtain a smooth consistency of the mortar.

[0154] The mixture is then ready to be sprayed (or injected in the case of preparation of construction elements)

[0155] Examples of formulations

[0156] Different formulations of earth mortar were prepared and made it possible to arrive at the formula according to the invention. The earths tested included gypsum, quarry waste (limestone), silts and clays.

[0157] Some tested formulas are described in Tables 1 to 4.

[0158] [Tables 1] VOLUME MATERIAL (liters) DENSITY WEIGHT (kg) % VOLUME % MASS LIME 25 0.791 19.78 22% 16.84% SLAG 25 1.165 29.13 22% 24.80% EARTH 25 1.545 38.63 22% 32.89% RECYCLED GRAVEL 4 / 6 12.5 1.26 15.75 11% 13.41% NATURAL FIBER 12.5 0.156 1.95 11% 1.66% CRYSTALLIZER R 2 1.114 2.23 2% 1.90%

[0159] [Tables2] VOLUME MATERIAL (liters) DENSITY WEIGHT (kg) % VOLUME % MASS LIME 14 0.791 11.07 13% 9.31% SLAG 28 1.165 32.62 25% 27.41% EARTH 28 1.545 43.26 25% 36.35% RECYCLED GRAVEL 4 / 6 14 1.26 17.64 13% 14.82% NATURAL FIBER 14 0.156 2.18 13% 1.84% CRYSTALLIZER R 2 1.114 2.23 2% 1.87%

[0160] [Tables3] VOLUME MATERIAL (liters) DENSITY WEIGHT (kg) % VOLUME % MASS LIME 10 0.791 7.91 9% 6.75% SLAG 30 1.165 34.95 27% 29.83% EARTH 30 1.545 46.35 27% 39.56% RECYCLED GRAVEL 4 / 6 10 1.26 12.60 9% 10.75% NATURAL FIBER 20 0.156 3.12 18% 2.66% CRYSTALLIZER R 2 1.114 2.23 2% 1.90%

[0161] [Tables4] VOLUME MATERIAL (liters) DENSITY WEIGHT (kg) % VOLUME % MASS LIME 5 0.791 3.96 5% SLAG 15 1.165 17.48 14% 14.88% EARTH 40 1.545 61.80 37% 52.61% GRAVEL 4 / 6 RECYCLED 15 1.26 18.90 14% 16.09% NATURAL FIBER 20 0.156 3.12 19% 2.66% CRYSTALISER 2 1.114 2.23 2% 1.90%

[0162] Earth mortar projection step

[0163] The projection of the earth mortar is then carried out on a previously prepared support.

[0164] In the tests carried out, wooden frames were produced, which frames had a base made of OSB plywood panel screwed to the wooden structure and a welded mesh type metal grid positioned mid-frame to allow the incorporation of elements traditionally used in the building trades (electrical wiring, water supply, etc.).

[0165] The projection of the different earth mortars described above was then carried out in two successive layers of 7 to 8 cm. The covering time between the two layers was 30 minutes.

[0166] This time can be considered short because in reality the panels produced on a conventional construction site are larger. This will systematically give a longer recovery time (around 1 to 2 hours).

[0167] In the end, the filling panels produced in the workshop represented a final thickness of 15 cm. After projection, the mortar held perfectly and a finish was carried out (rule, float or trowel depending on the panels).

[0168] Properties of earth mortar

[0169] Earth mortar specimens were produced to test its properties.

[0170] The tests carried out are as follows:

[0171] Test on hardened concrete according to standard NF P18-459

[0172] Thermal conductivity test by the metric flux method according to the NF standard EN 12667

[0173] Hygrometric performance test by determining hygroscopic sorption properties. (Sorption and desorption curve) according to standard NF EN ISO 12571.

[0174] Air permeability and water tightness test.

[0175] Compression tests according to standard NF EN 12390-3 (by comparison with control elements).

[0176] Determination of dimensional variations due to humidity of aggregate concrete masonry elements according to standard NF EN 772-14. For each configuration.

[0177] Accelerated Freeze / Thaw aging tests according to standard NF EN 771-1 +A1 / CN

Claims

1. Claims A method of spraying an earth-based mortar with a spraying machine, which method comprises the steps of: (i) preparation of earth-based mortar by mixing: (ia) earth from earthworks or excavation operations (quarry), or crushed deconstruction materials (concrete, brick, plaster, stone, and mortar), excluding topsoil, with a grain size less than or equal to 20 mm in a volume proportion of 20 to 55%; (ib) a binder comprising slag or metakaolin and, optionally, lime, in a volume proportion of 15 to 55%; (ic) aggregates with a particle size between 2 and 20 mm, and in a volume proportion of 0 to 20%; id) fibres in a volume proportion of between 0 and 30%; ie) crystallizer in a volume proportion of between 0.1 and 15%; and if) water in a volume proportion of between 5 and 20%; ii) pouring the mixture, at the end of step i), into a loading hopper which is fixed to the frame of the spraying machine, iii) pumping the mixture through an orifice of this same loading hopper, by a sparrow pump and injection of this mixture into a pipe extending said pump; and iv) projection, towards a surface, of the mixture at the end of the pipe by a lance terminating in a nozzle, preferably a vertical surface; Or - the sparrow pump does not have a jacket for spraying single-layer coating (e.g. type 2L6 or 2R6) but a jacket for liquid screed (e.g. type 60 / 12 or T25 or 2L7); - the piping, if it is less than 10 metres long, has an internal diameter of approximately 35 mm or, if it is more than 10 metres long, an internal diameter of approximately 50 mm at the sparrow pump outlet and an internal diameter of approximately 35 mm over its last 10 metres; - a projection lance body with an internal diameter of approximately 35 mm with a nozzle having a diameter of between 16 and 22 mm; and - a compressed air line opening at the end of the nozzle for allow the projection of the earth-based mortar onto the surface.

2. The method according to claim 1, characterized in that the mixing step i) is carried out in a mixing container of the spraying machine, which mixing container is capable of pivoting about a horizontal tilting axis around the frame so as to allow the mixture to be poured into the loading hopper.

3. The method according to claim 1, characterized in that it allows up to 14m3 of earth-based mortar to be projected per day.

4. The method according to any one of claims 1 to 3, characterized in that step iii) of pumping the mixture through an orifice of this same loading hopper, by a sparrow pump and injection of this mixture into a pipe extending said pump is carried out at a pressure of between 8 and 18 bars.

5. The method according to claim 4, characterized in that step iii) of pumping the mixture through an orifice of this same loading hopper, by a sparrow pump and injection of this mixture into a pipe extending said pump is carried out at a pressure of between 10 and 12 bars.

6. A spraying machine which comprises a loading hopper which is fixed to its frame, a sparrow pump connected to an orifice of this same hopper and which allows the pumping and injection of the mixture into a pipe extending said pump; and at the end of the pipe, a lance ending in a nozzle, characterized in that: - the sparrow pump does not have a jacket for the projection of single-layer coating (e.g. type 2L6 or 2R6) but a jacket for liquid screed (e.g. type 60 / 12 or T25) or a jacket for traditional mortar (e.g.2L7); - the piping, if it is less than 10 metres long, has an internal diameter of approximately 35 mm or, if it is more than 10 metres long, an internal diameter of approximately 50 mm at the sparrow pump outlet and an internal diameter of approximately 35 mm over its last 10 metres; - a projection lance body with an internal diameter of approximately 35 mm with a nozzle having a diameter between 16 and 22 mm; and - a compressed air line opening at the end of the nozzle to allow the projection of the earth-based mortar onto the surface.

7. A use of a spraying machine according to claim 6 for implementing a method of spraying an earth-based mortar resulting from the mixture of: ia) earth from earthworks or excavation operations (quarry), or crushed deconstruction materials (concrete, brick, plaster, stone, and mortar), excluding topsoil, with a grain size less than or equal to 20 mm in a volume proportion of 20 to 55%; ib) a binder comprising slag or metakaolin and, possibly lime, in a volume proportion of 15 to 55%; ic) aggregates with a grain size between 2 and 20 mm, and in a volume proportion of 0 to 20%; id) fibers in a volume proportion of between 0 and 30%; ie) the crystallizer in a volume proportion of between 0.1 and 15%; and if) water in a volume proportion of between 5 and 20%.

8. A kit for a spraying machine comprising: - a jacket for liquid screed (e.g. type 60 / 12 or T25) or for traditional mortar (e.g. 2L7); - a spraying lance body with an internal diameter of approximately 35 mm with a nozzle having a diameter of between 16 and 22 mm - a compressed air line opening at the end of the nozzle to allow the earth-based mortar to be sprayed onto the surface; Optionally, a pipe, if it is less than 10 meters long, has an internal diameter of approximately 35 mm or, if it is more than 10 meters long, an internal diameter of approximately 50 mm at the sparrow pump outlet and an internal diameter of approximately 35 mm over its last 10 meters;

9. A use of a kit according to the preceding claim to enable the implementation, from a projection machine, of a method for projection of an earth-based mortar resulting from the mixing of: ia) earth from earthworks or excavation operations (quarry), or crushed deconstruction materials (concrete, brick, plaster, stone, and mortar), excluding topsoil, with a particle size less than or equal to 20 mm in a volume proportion of 20 to 55%; ib) a binder comprising slag or metakaolin and, optionally, lime, in a volume proportion of 15 to 55%; ic) aggregates with a particle size between 2 and 20 mm, and in a volume proportion of 0 to 20%; id) fibers in a volume proportion of between 0 and 30%; ie) crystallizer in a volume proportion of between 0.1 and 15%; and if) water in a volume proportion of between 5 and 20%;

10. The use according to claim 9, characterized in that the projection machine is a facade projection machine.