FR2885624A1 - Base unit`s e.g. ground floor, lateral wall constructing method for prefabricated building, involves pouring and hardening cement material in molds delimited by panels, where material is penetrated into perforations and is solidified - Google Patents

Abstract

The method involves pouring and hardening a cement based material around a metal frame (3), in molds delimited from the side exterior to a building by perforated panels (9) constituting the outer side of lateral walls of a base unit (1). The material is a mixture of sand, filler wood, water repellent cement, and is penetrated into perforations (11) of the panels and is solidified, so that the panels are found integrated to the wall. The panels comprise a beading of 10 centimeters. Independent claims are also included for the following: (1) a base unit of a prefabricated building (2) a building constructing method by prefabrication of the base unit.

Description

2885624 1

  The present invention relates to the design and implementation of a method of constructing a structural element of a prefabricated building, more particularly with regard to the manufacture of the side walls of this element, as well as the element obtained by way of this process. This process is part of a more general process of constructing a building by factory prefabrication of components and assembly on the construction site, which is also the subject of the present invention.

  Prior art is known for methods for constructing prefabricated factory buildings. Following these processes, the entire building, or nodular elements of the building, are manufactured in the factory. This manufacture can go to the so-called finishing work operations, that is to say, in particular to the assembly of the internal partitions and the installation, in these partitions, of the various pipes and electric wires necessary for feeding electricity and water of the different parts of the buildings, as well as the evacuation. Once factory fabrication is completed, the building, or its components, is transported to the construction site, where the foundations have been prepared. The building is then installed on the foundations, with possible assembly of its modular elements. Such building processes generally have the advantage of enabling a building to be built in short time and at low industrial cost, since all the operations are carried out in the factory under conditions of mass industrial production. in the application of such processes, lies in the transport phase of the building, or its modular elements, from the factory to the construction site. This is mainly due to the heavy weight that needs to be transported. For ease of transport, it has been proposed in the prior art various lightened materials that can be used to fill the walls of the building. However, such a lightening of the walls causes their embrittlement. There is a risk that the elements transported, if they are not strong enough, are deformed or damaged during handling and transport.

  The present invention aims to provide a method of constructing a prefabricated building which ensures a solidity of the building or its constituent elements which is sufficient to avoid any risk of damage or deformation during transport from the factory to at the construction site.

  To this end, the invention proposes a method of constructing a constituent element of a prefabricated building, according to which the side walls of the element are made by casting, and curing, a cementitious material in the form of liquid around a metal frame, in molds delimited on the outside of the building by perforated metal panels constituting the outer face of each of the walls.

  The component may consist of a part of the building, whether it is a part of ground floor or floor. It may also be the entire building.

  Side walls are understood to mean both the peripheral walls of the building, which delimit it with respect to the external environment, and the interior walls delimiting the different rooms. In particular, it is entirely advantageous that, in addition to the outer walls, the inner walls acting as support for the upper part of the building are also made in accordance with the method according to the invention, thus ensuring their strength while increasing their lightness.

  The metal panels constitute an outer formwork wall for the realization of the walls. During the implementation of the construction process, the material in liquid form which is poured penetrates the perforations of the metal panels, and there solifidie by hardening. The metal panels are thus secured to the walls, which stiffens them, thus making them more resistant to the forces that can be exerted on them during their transport.

  The inner form is in turn realized in a conventional manner, for example by means of wood panels.

  The metal panels thus disposed on the external faces of the building advantageously constitute a support on which the external coatings can be applied. For this purpose, a wire mesh is fixed on the panel. The different plaster layers are then applied to this lattice, according to conventional techniques in themselves.

  The metal panels according to the invention thus advantageously have several roles: they constitute an external formwork for the casting of the material constituting the walls of the building, they stiffen these walls, and they allow: the direct application of the various external coatings of the building.

  The invention also does not exclude the case where the side walls are formed not in the factory, but directly on the construction site. However, it is particularly advantageous in the case where the component, manufactured in the factory, must be transported, and it requires for this to have a good strength.

  According to an advantageous characteristic of the invention, the cement-based material constituting the side walls comprises a mixture of sand, sawdust and water-repellent cement in water. Such a composition advantageously confers a great lightness to the walls, thus facilitating the handling and transport of the element. In addition, this composition has particularly good thermal and acoustic insulation properties. In particular, sawdust, preferably derived from oak or blarK: wood, gives the material good insulating properties. Sand provides good wall strength, as does cement, which plays the classic role of a hydraulic binder.

  According to preferred embodiments in industrial practice, the invention furthermore meets the following characteristics, implemented separately or in each of their technically operating combinations.

  By these characteristics, the invention aims in particular to ensure the lightness and strength of the building component, 2885624 4 to facilitate its transport in good conditions.

  In preferred embodiments of the invention, the metal panels have perforations of size between 4 and 20 mm, spaced from 10 to 20 mm from each other. Such a mesh advantageously provides a solid attachment of the panels to the hardened material constituting the walls, while imparting significant rigidity to the assembly.

  Any metal can be used for the constitution of the panels. However, from the point of view of the industrial cost, the weight and the strength necessary for the implementation of the invention, it will be preferred to use steel panels, preferably galvanized, so as to prevent the formation of rust and to ensure a better longevity of the panels.

  According to an advantageous characteristic of the invention, the panels have a ribbed shape resulting in an additional stiffening effect of the walls.

  They preferably have anti-moisture properties, so that they participate, in addition to external coatings, to protect the walls from moisture.

  In preferred embodiments of the invention, the panels are provided with protuberances extending inside the mold. These protuberances, which are preferably distributed over the entire height of the panels, are inserts that integrate into the cured material and which promote the formation of cracks at this location. The formation zones of the cracks which are naturally created during the curing of the material by drying are thus advantageously controlled. These protuberances are preferably made so as to sink up to a third to two thirds of the thickness of the walls.

  In preferred embodiments of the invention, the cementitious material constituting the walls comprises 35 to 60% by weight of sand, 15 to 40% by weight of sawdust, and 20 to 40% by weight. of cement.

  According to a preferred feature of the invention, the material further comprises rock dust which acts both as a binder of the mixture, a role of lagging walls, and is water repellent.

  The material preferably further comprises synthetic fibers, which are conventional in themselves, and which, by forming an additional binder in the mixture, advantageously imparts greater wall stiffness.

  The metal frame is preferably made of hollow tubes, thus advantageously conferring greater lightness to the assembly. These tubes are welded to each other so as to form a framework in one piece, which therefore has a high strength.

  According to an advantageous characteristic of the invention, the metal frame comprises two peripheral frames respectively forming the upper periphery and the lower periphery of the base element, which are connected to each other by uprights. These two frames help to stiffen the structure.

  Still for the same purpose of providing a light and rigid element, the invention furthermore advantageously provides that the metal frame comprises, in addition to upright amounts, oblique amounts. Such oblique amounts stiffen the side walls.

  In preferred embodiments of the invention, the perforated metal panels are attached to the framework by their upper edges and their lower edges, in particular by screwing. This advantageously has an element whose basic structure, consisting of the metal frame and the perforated panels, is constituted in one piece, although it is all the more rigid and solid.

  The invention also relates to a constituent element of a prefabricated building, as it can be obtained by the construction method described above.

  This manufacturing process is part of a more general process of constructing a prefabricated building, by prefabrication in factory of components of said building and assembly on the construction site, which also makes object of the present invention.

  According to this method, the foundation or concrete slab for the reception of the building is produced on the construction site, and a base element constituting a lower floor of the building, comprising the floor support and the side walls, is manufactured at the factory. of the building, and a roof element comprising the ceiling support of the lower floor and the roof of the building. The base element has a peripheral metal frame on its upper periphery, and the roof element has a peripheral metal frame on its lower periphery.

  The manufacturing steps carried out in the factory relate to the so-called first work, such as the realization of the side walls, as well as the so-called finishing work, or finishing. The basic element is obtained in the factory according to the construction method described above, with regard to the production of the side walls.

  The base element and the roof element are then transported to the construction site and placed on top of the foundation slab. They are then assembled by fixing the two peripheral metal frames to one another.

  This process provides a quick and easy way to build a building. The transport of the elements to the construction site does not pose any particular problem, thanks to the strength and lightness of the walls of the base element. In addition, the assembly of the two elements to one another on the site of construction is easy and quick to implement.

  In preferred embodiments of the invention, the metal frame forming the upper contour of the base element advantageously allows both the attachment of the perforated panels delimiting the side walls, and the assembly to the element. roof.

  According to a preferred feature of the invention, the floor support of the base element is constituted by a grid of metal tubes, which is fixed to the metal frame of the side walls, in particular by welding.

  The roof element preferably comprises a metal framework for fixing the roof elements and the ceiling of the lower stage, which is preferably made in one piece.

  The invention will now be more completely described in the context of preferred features and their advantages, with reference to FIGS. 1 to 4 in which: FIG. 1 shows a view of the metal frame of a base element of FIG. a building obtained by means of the method according to the invention; - Figure 2 shows a sectional view along a transverse plane of a side wall of the element of Figure 1, after the casting of the cementitious material; - Figure 3 illustrates the metal frame of the floor support of a base member according to the invention in top view; - And Figure 4 is a partial view of the metal frame of a roof element according to the invention.

  According to the construction method according to the invention, the building is entirely prefabricated in the factory, with the exception of the last layer of exterior plaster, and any floor tiles.

  As part of this example, this is a classic rectangular building. However, it is conceivable in the context of the invention to construct buildings of all other possible forms.

  This building consists of two main elements, which are built at the factory and assembled together: at the site, in an ultimate stage of construction: a base element 1, comprising the floor support and the walls side, and a roof element 2, which comprises the ceiling of the base element 1 and the roof 2885624 8 itself. The roof element 2 may optionally be arranged to form an upper floor of the building.

  The base element 1 has a rectangular shape. It is formed of a metal frame 3. This framework is formed by means of hollow profiles, preferably made of a material both solid and light, for example steel. These tubes are joined to each other by welding, so as to form a frame in one piece, as shown in Figure 1. This frame 3 is the base of the side walls of the building.

  The inner walls that play a role in the building are also made on the basis of this frame.

  The frame 3 comprises two peripheral frames which are located respectively on its upper periphery and its lower periphery: the upper frame 4 and the lower frame 5. These frames are connected to each other by vertical uprights 6. Such uprights are arranged at the four corners of the building, and at regular intervals, especially every 60 cm to 120 cm, in the side walls, so as to give good strength to the frame. Additional crosspieces 7 are also provided on the upper and lower faces of the element 1, at regular intervals, so as to further consolidate the framework. The latter also comprises oblique amounts 8, which act as tensioners, and which further stiffen the element, so as to promote its transportability. These tensioners prevent bending of the walls, especially during transport. They join the uprights 6, at a height between 120 and 150 cm, to the lower frame 5. The maximum strength is obtained when these tensioners form an angle of between 35 and 45 degrees with the vertical, depending on the length of the building.

  The walls are made of a cementitious material which is cast around the metal framework. It is maintained during casting by a formwork which is constituted, on the outside of the building, by perforated metal panels 9. On the interior side of the building, the formwork is made by wooden panels 10 according to a conventional technique in itself. even. These panels are shown in FIG. 2. They are removed when the material constituting the walls has sufficiently solidified.

  Perforated panels 9 are made of a material that is both strong and lightweight, especially galvanized steel. They have a thickness of about 0.6 to 0.8 mm. They have anti-humidity properties, so they help protect the inside of the walls of the building from moisture. They are preferably watertight at more than 70%.

  The perforated panels 9 are assembled one after the other all along the walls. They are fixed by their opposite edges respectively to the upper frame 4 and the upper frame 5, in particular by screwing. They are also attached to each other for strength.

  The perforations 11 of these panels have a diameter of between 4 and 20 mm, in particular equal to 4 or 5 mm. They are spaced 10 to 20 mm apart from one another.

  When poured into the walls, the liquid material enters the perforations 11 of the perforated panels 9, and it solidifies, so that the panels are secured to the wall. This advantageously makes it possible to stiffen the walls of the element, which leads to a better resistance to the forces exerted on them during the transport of the element 1.

  The perforated panels 9 have a ribbing of about 10 cm, which gives them a better strength.

  They also advantageously have sound-insulating properties due to the material constituting them.

  Each of the panels 9 has protuberances extending inwardly of the element 1. In a preferred embodiment of the invention, there are returns 12 arranged along the opposite longitudinal edges of each of the panels. 9, as illustrated in Figure 2.

  In this figure, which shows a sectional view along a transverse plane of a wall according to the invention, there are perforated panels 9, each provided with two returns 12, and the cementitious material 13 by train. to solidify within the mold formed by the perforated panels 9 and the wood panels 10.

  The returns 12 extend in the walls for a length of between one third and one half of the thickness of the latter. For example, for walls with a thickness of about 20 cm, the returns 12 extend over a length of about 7 to 10 cm. They are spaced about 50 to 100 cm apart, in particular about 10 cm from each other, which corresponds to the width of each panel 9.

  The returns 12 are thus included in the cast material. They create a crack initiation in the material during the hardening thereof. This makes it possible to control the location of the zones of cracking which are naturally created during the drying of the material.

  The returns 12 have at their end 14 a U-shape, which advantageously allows them to be inserted into each other for their assembly, thus simplifying their attachment to each other, as illustrated in FIG. 2.

  The material used for producing the walls has improved lightness properties compared to conventional cements. It consists of a mix of saDIe, sawdust and cement in water.

  It comprises, for 1 m 3 of material in liquid form: 35 to 60%, preferably 45% of sand, which is preferably of large size to give the cured material 40% strength, preferably 15% of sawdust, preferably of oak or white wood, which gives lightness and good insulating properties to the hardened material, at 40%, preferably 35% water-repellent cement, which 2885624 11 plays a role of hydraulic binder, 4 to 20%, preferably 4.9% of rock dust, preferably of small caliber, which plays in the mixture both the role of binder and a role of insulation, - 0.05 to 0, 1%, preferably 0.1% of fiber: 3 synthetic or metallic, or welded mesh, which act as an additional binder conferring more rigidity to the walls formed from this material, in water in sufficient quantity for 1 m3.

  The percentages given above are expressed by weight relative to the total weight of the composition.

  This material confers both rigidity and lightness to the formed walls, while having good thermal and sound insulation properties. It has a weight when cast which is between 950 and 1200 kg / m3.

  It requires about 6 hours to solidify. It is strong enough to be demolded after about 12 hours.

  The metal frame 3 also comprises, at the side walls, structures incorporating frames 15 for mounting doors and windows. The assembly operation of the doors and windows is performed in the factory, before or after the casting of the material constituting the walls, according to conventional methods in themselves.

  All so-called second work operations are also carried out in the factory, for example Bn placing internal partitions.

  Conventional exterior coatings are applied to the outer faces of perforated panels 9. For this, a wire mesh is fixed on these faces, providing an air gap between the two parts, as provided in conventional methods of application exterior coatings.

  Once the internal formwork of the walls, consisting of the wood panels 10, has been removed, the various plumbing pipes and electrical cables are fixed to the walls, then a coating layer, in particular consisting of plasterboard (registered trademark). , is applied, leaving an air gap between it and the wall. This is done conventionally.

  The base element 1 also comprises a floor support, which consists of a metal frame 16. This frame is not shown in Figure 1 for reasons of clarity. It is constituted, as illustrated in Figure 3, a set of tubes forming a grid. This gives a grancle rigidity to all, which helps to make it fit to be transported. The grid is made at right angles, so as to form a practical support for the support of the floor.

  The frame 16 is assembled to the lower frame 5 of the element 1 so as to form a global framework in one piece, in particular by welding.

  This floor frame 16 will serve as a support for a floor. For the installation of a tiling, concrete will be poured around it according to a classical technique. These operations will rather be carried out on the construction site, to avoid the risk of breakage of the tiles during transport.

  The roof element 2 is also formed of a metal frame 17 in one piece, which is formed in the same way as the frame 3 of the base member 1, by means of hollow tubes assembled to each other by welding. The frame 17 is a support for the roof, as well as for a floor partition which will be the ceiling of the lower floor. It is illustrated in Figure 4.

  The frame 17 has a peripheral frame 18 which is located on its lower periphery. This frame has the same dimension as the upper frame 4 of the base element 1.

  In the lower frame 18 is fixed a floor support formed of transverse metal tubes 19, on which will be assembled a floor.

  Above the frame 18, the frame 17 can have all kinds of shape, depending on the style that you want to give to the roof of the building, and whether you want it or not to have an upper floor. In the preferred embodiment shown in FIG. 4, the framework is adapted to the formation of an upper stage. It comprises vertical uprights 20, in a sufficiently large number to ensure the strength of the assembly, in particular arranged every 60 cm, which connect the lower frame 18 to an upper peripheral frame 21. It also comprises inclined amounts 22 connecting the frame 21 to a beam, 23 constituting the ridge of the roof.

  The roof is placed on the frame 17 according to conventional techniques.

  The two elements of the building are transported independently of each other to the construction site. The transport is made easily, on the one hand because of the lightness of each element, and on the other hand because of their solidity. Both elements have indeed a high resistance to the deformation forces that are exerted on them during transport.

  The building is preferably sized so that it has an outside width of less than 4.5 m, which allows it to be transported on the road without the need for a police escort. This outer width -e corresponds to an inner width of about 4 m. It has a length that can go up to 12 m.

  The foundations are made on site, preferably by preparing a concrete slab having a cavity about 10 cm deep and equal in area to the ground surface of the base member 1, for receiving the latter.

  The basic element 1 is deposited on the fndations. Its fixing on the latter is achieved by simple support, the weight of the building, of the order of several tens of tons, ensuring a solid anchorage on the ground.

  The roof element 2 is then deposited on the base element 1, the lower frame 18 resting on the upper frame 4 of the base element.

  The fixing of the two elements to one another is carried out as follows: orifices are drilled in the floor of the roof element 2, and the two respective frames 4 and 18 are fixed one to the other. other. The holes are plugged after fixing. Screw fixing is preferably carried out. It is advantageously carried out approximately every 4 m, which corresponds, for a building 4.5 m wide by 12 m long, to a total of 8 orifices. Fixing is carried out above the side walls, where it is the most solid.

  The upper frame 4 of the base element 1 thus advantageously plays several roles: a first role of stiffening the element, which contributes to facilitating its transport, a second supporting role for fixing the perforated panels 9, and finally a final role for assembly to the roof element 2.

  The construction of the building according to the method according to the invention, made entirely in the factory, is fast. For example, a house of about 100 m2 of living space can be built by three people full time, it lasts about 3 months. This results in a great saving of construction costs compared to buildings built in traditional way on site.

  The foregoing description clearly explains how the invention achieves the goals it has set for itself. In particular, it proposes a method of building a prefabricated building that is fast and easy to implement. The method of producing the side walls of the building ensures besides great strength, at the same time as lightness, the latter. This makes it particularly easy to transport from the factory to the construction site.

  Nevertheless, it is apparent from the foregoing that the invention is not limited to the embodiments which have been specifically described and shown in the figures, and that it extends on the contrary to any variant passing through the equivalent means.

  In particular, each of the elements, be it the base element or the roof element, can be delivered in one piece, or in the form of two or more modules to be assembled to each other on site.

2885624 16

Claims (17)

  A method of constructing a constituent element (1) of a prefabricated building, characterized in that the sidewalls of said element (1) are made by casting, and curing, of a cementitious material in liquid form. around a metal frame (3), in molds delimited on the outside of said building by perforated metal panels (9) constituting the outer face of each of said walls.   2. Construction method according to claim 1, characterized in that said panels (9) have perforations (II) of size between 4 and 20 mm, spaced from 10 to 20 mm from each other.   3. A method of construction according to claim 1 or 2, characterized in that said panels (9) have a ribbed shape causing a stiffening effect of said walls.   4. Construction method according to any one of claims 1 to 3, characterized in that said panels (9) have anti-moisture properties.   5. Construction method according to any one of the preceding claims, characterized in that said panels (9) are provided with protuberances (12) extending inside said mold, which constitute inserts which integrate into said hardened material (13) and which promote the formation of cracks there.   6. Construction method according to any one of claims 1 to 5, characterized in that said material comprises a mixture of sand, sawdust and water-repellent cement in water.   7. Construction method according to claim 6, characterized in that said material further comprises rock dust.   8. Construction method according to claim 6 or 7, characterized in that said material further comprises synthetic fibers.   9. Construction method according to any one of claims 6 to 8, characterized in that said material comprises 35 to 60% by weight of sand, 15 to 40% by weight of sawdust, and 20 to 40% by weight of cement.   10. A method of construction according to any one of claims 1 to 9, characterized in that said metal frame (3) consists of hollow tubes, which are welded to each other so as to form a framework in one piece.   11. A method of construction according to any one of claims 1 to 10, characterized in that said frame (3) comprises two peripheral frames (4, 5) respectively forming the upper periphery and the lower periphery of said base member (1), connected to each other by uprights (6).   12. A method of construction according to any one of claims 1 to 1 1, characterized in that said frame (3) comprises, in addition to uprights (6), oblique amounts (8) stiffening said side walls.   MNOI-1B2 EF / MH Oct.2005 ï 13. A method of construction according to any one of claims 1 to 12, characterized in that said panels (9) are fixed to said framework (3) by their upper edges and their lower edges, in particular by screwing.   14. Component of a prefabricated building, obtainable by the method of construction according to any one of claims 1 to 13.   15. A method of constructing a building by factory prefabrication of constituent elements of said building and assembly on the construction site, characterized in that: - the foundations or a concrete slab for the construction site are produced reception of said building, - a base element (1) constituting a lower floor of the building, comprising the floor support and the side walls of the building, is manufactured in the factory, and a roof element (2) comprising the ceiling support of the lower floor and the roof of the building, said base element (1) having a peripheral metal frame (4) on its upper periphery and said roof element (2) having a peripheral metal frame (18) on its lower periphery, the base element (1) and the roof element (2) are transported to the site of the construction, - the base element (1) and the roof element (2) are deposited. on the other on the slab of the fondat ions, and are assembled by fixing the two peripheral metal frames (4, 18) to each other, and in that said base member (1) is obtained at the factory by the method of construction according to one any of claims 1 to 13.   2885624 19 16. Construction method according to claim 15, characterized in that the floor support of said base element (1) consists of a grid of metal tubes (16), which is fixed to the frame (3) of said side walls. , especially by welding.   17. Construction method according to claim 15 or 16, characterized in that said roof element (2) comprises a metal frame (17) for fixing the roof elements and the ceiling of the lower floor, preferably made of one piece.