EP1431015B1 - Process for making reinforced concrete beams and installation for the execution of this process - Google Patents

Abstract

The method of fabrication of cast concrete beams (1) involves preparing prefabricated assemblies (5) including armature cages (2) which are positioned with respect to each other to suit the functions of each beam to be made. The pre assembled cages are positioned in the moulds and the concrete poured in. After drying the beams are demoulded and passed to store. Claims include an installation for moulding beams using the method.

Description

The present invention relates to a method of manufacturing concrete beams obtained by molding in a molding bench. The invention also relates to an installation implementing this method and comprising at least one molding zone provided with a molding bench.

Concrete beams, generally used in building and civil engineering, are generally reinforced concrete beams, in which case the concrete is reinforced with metal reinforcements, or prestressed concrete beams, in which case concrete is in addition, put under stress by prestressing tendons stretched during the molding phase and then relaxed after curing the concrete.

Conventionally, the molds used for the manufacture of this type of beams extend over a great length, for example from 60 to 120 meters, and are each cut into a number T of longitudinal sections, by means of spacers or spacers. formwork combs, for manufacturing a number T of beams forming a set. These molds are joined in a molding bench, which has a number M of parallel molds between them, which may have different sections. Thus, each molding bench allows the simultaneous realization of a number M of sets of beams, which can have different lengths and sections. Until now, each mold is prepared individually and manually by one or more operators who set up the reinforcing cages and the spacers or formwork combs at locations defined according to the length of the reinforced concrete beams to be manufactured, as described for example in the publication EP-A-0 606 794 . For prestressed concrete beams, they add prestressing cables that run the full length of the molds and are pulled by a tensioning device, as described for example in the publication WO-A-97/18070 .

To perform these preparatory operations, the operators work bent over the molds, which is a very uncomfortable position, causing premature fatigue and musculoskeletal disorders. This work is very long and tedious. In addition, it monopolizes the molding bench for long periods, these downtimes being variable depending on the complexity of the beams to be manufactured. When placing the pre-stressing cables in the molds, these cables that are not live are in contact with the demolding oil present in the bottom and on the walls of the molds, which can be detrimental to the performances. finished product techniques. The setting of the reinforcement cages and formwork spacers is manual, the accuracy of their positioning is relative and not reproducible.

During the manufacture of prestressed concrete beams, after pouring and hardening of the concrete, the prestressing cables are released and then cut inside the molds, either with a blowtorch or by a circular saw, with all the risks and difficulties that this represents: difficult access, alteration of the mold walls, heavy soiling, danger for the operator, etc. The finished beams are then demolded one by one which, added to the previous tasks, immobilizes the molding bench over a very long period of time. The current manufacturing process does not allow to consider optimal management of the production tool, nor better working conditions for operators.

The present invention aims to overcome these disadvantages by proposing a new semi-automated or automated manufacturing process, which eliminates the difficult tasks related to the handling of heavy elements and difficult working positions, ensures accurate manufacturing of reinforcements, deportes in out of the molding molding bench the pre-molding and post-molding processing operations, thereby reducing the downtime of the molding bench, allows a high production flexibility and optimizes the overall efficiency of the manufacturing plant .

1. a) on prépare, en dehors dudit banc de moulage, au moins un ensemble d'éléments pré-assemblés comprenant au moins les cages d'armature entrant dans la fabrication de ladite poutre, ces éléments étant positionnés l'un par rapport à l'autre à des emplacements prédéterminés en fonction de la poutre à fabriquer,
2. b) on prélève cet ensemble d'éléments pré-assemblés d'un seul tenant à l'aide de moyens de préhension pour le déposer à l'intérieur dudit moule,
3. c) on coule le béton dans ledit moule,
4. d) après durcissement du béton, on démoule ladite poutre fabriquée d'un seul tenant à l'aide desdits moyens de préhension, puis
5. e) on l'évacue vers une aire de stockage.

For this purpose, the invention relates to a method of manufacture of the type indicated in the preamble, wherein the molding bench comprises at least one mold arranged to allow the manufacture of at least one beam, characterized in that it comprises at least the following steps, at least one of which is performed semi-automatically or automatically:

1. a) outside of said molding bench, at least one set of pre-assembled elements comprising at least the reinforcement cages used in the manufacture of said beam are prepared, these elements being positioned relative to one another; other at predetermined locations depending on the beam to be manufactured,
2. b) this set of pre-assembled elements is taken in one piece by means of gripping means to deposit it inside said mold,
3. c) pouring the concrete into said mold,
4. d) after hardening of the concrete, said integrally manufactured beam is demolded by means of said gripping means, then
5. e) evacuated to a storage area.

For this purpose, the invention also relates to a manufacturing facility of the type indicated in the preamble, characterized in that it comprises at least one preparation zone of at least one set of pre-assembled elements positioned relative to the other depending on each beam to be manufactured and comprising at least reinforcing cages, this preparation zone being disposed outside said molding zone, and gripping means arranged to take a single piece of said set of elements pre-assembled of said preparation zone and depositing it in the molding bench of said molding zone, before pouring the concrete.

Advantageous embodiments of this method and plant are defined in claims 2 to 8 and 10 to 18, respectively.

• les figures 1A et 1B représentent en perspective, respectivement, un exemple de poutre réalisée par le procédé et l'installation selon l'invention et un exemple de cage d'armature entrant dans la fabrication de cette poutre,
• la figure 2 représente une installation selon l'invention en vue de dessus,
• la figure 3 représente l'installation de la figure 2 en coupe transversale,
• la figure 4 représente la zone de préparation des cages d'armature en vue de côté,
• la figure 5 représente les moyens de préhension des cages d'armature en vue longitudinale, et
• les figures 6A à 6C représentent les dispositifs de traction des câbles de précontrainte respectivement en vues partielles de côté en position de repos et en position de travail et en vue de face.

The present invention and its advantages will appear better in the following description of an embodiment, given by way of non-limiting example, with reference to the appended drawings, in which:

• the Figures 1A and 1B represent in perspective, respectively, an example of a beam produced by the method and the installation according to the invention and an example of a reinforcement cage used in the manufacture of this beam,
• the figure 2 represents an installation according to the invention in plan view,
• the figure 3 represents the installation of the figure 2 in cross-section,
• the figure 4 represents the zone of preparation of the reinforcement cages in view from the side,
• the figure 5 represents the gripping means of the reinforcement cages in longitudinal view, and
• the Figures 6A to 6C represent the traction devices of the prestressing cables respectively in partial side views in the rest position and in the working position and in front view.

With reference to the figures, the installation 10 according to the invention makes it possible to manufacture reinforced concrete or prestressed concrete beams, of different sections and lengths. In the first case, the beams are reinforced by metal reinforcements only, while in the second case, these beams are further stressed by metal prestressing cables. The Figure 1A illustrates an example of prestressed concrete beam 1, reinforced by reinforcement cages 2 and stressed by prestressing cables 3. The beam 1 as illustrated has a substantially rectangular section, given by way of non-limiting example. , this section can be square, frustoconical, T or any other section suitable for molding.

This installation 10 makes it possible to implement a new manufacturing process in which the beams 1 are manufactured by molding in a molding bench 40 comprising several molds 41 and whose length makes it possible to manufacture in each mold 41 several beams 1, called by following a set of beams 1.

• ◆ on prépare, pour chaque moule 41 et en dehors dudit banc de moulage 40, un ensemble d'éléments pré-assemblés 5 comprenant notamment des cages d'armature 2 (cf. fig. 1B), des câbles de précontrainte 3, des intercalaires de coffrage 4 et des pièces d'ancrage 6 (cf. fig. 5 et 6), ces éléments 2, 3, 4, 6 étant positionnés les uns par rapport aux autres à des emplacements prédéterminés en fonction dudit ensemble de poutres 1 à fabriquer,
• ◆ on prélève ledit ensemble d'éléments pré-assemblés 5 d'un seul tenant par des moyens de préhension 31 pour le déposer à l'intérieur dudit moule 41,
• ◆ on répète cette opération autant de fois qu'il y a de moules 41 à garnir,
• ◆ on met sous contrainte les câbles de précontrainte 3,
• ◆ on coule le béton dans les moules 41,
• ◆ après durcissement du béton, on démoule les ensembles de poutres 1 fabriqués l'un après l'autre d'un seul tenant par lesdits moyens de préhension 31,
• ◆ puis, pour chaque ensemble de poutres 1, on sectionne les câbles de précontrainte 3 entre deux intercalaires de coffrage 4 consécutifs pour séparer les poutres 1 les unes des autres avant de les évacuer vers une aire de stockage.

This new method is described for the manufacture of prestressed concrete beams 1, but of course extends to the manufacture of reinforced concrete beams. It is characterized by the fact that:

• ◆ for each mold 41 and outside said casting bench 40, a set of pre-assembled elements 5 is prepared, comprising in particular reinforcing cages 2 (cf. Fig. 1B ), prestressing cables 3, formwork spacers 4 and anchoring parts 6 (cf. Fig. 5 and 6 ), these elements 2, 3, 4, 6 being positioned relative to each other at predetermined locations according to said set of beams 1 to be manufactured,
• Said pre-assembled assembly 5 is taken in one piece by means of gripping means 31 for depositing it inside said mold 41,
• ◆ repeat this operation as many times as there are molds 41 to garnish,
• ◆ the prestressing cables 3 are stressed,
• ◆ the concrete is poured into the molds 41,
• After hardening of the concrete, the sets of beams 1 manufactured one after the other in one piece by said gripping means 31 are demolded,
• ◆ then, for each set of beams 1, the prestressing cables 3 are cut off between two consecutive form spacers 4 to separate the beams 1 from each other before discharging them to a storage area.

For the manufacture of reinforced concrete beams, the prestressing cables are removed and, consequently, the stressing operation of these cables before molding and then cutting these cables after demolding.

To implement this method, the installation 10 comprises several work zones and in particular a preparation zone A of sets of pre-assembled elements 5, a molding zone B of the beams 1, an evacuation zone C of the beams 1 manufactured (cf. Fig. 2 and 3 ). This installation 10, and more particularly the preparation zone A, is automated and controlled by one or more controllers receiving computer data from a design office relating to the various beams 1 to be produced (length, section, number and location of the cages reinforcement 2, number of prestressing cables 3, location of form spacers 4 and anchors 6, etc.).

The molding zone B comprises a molding bench 40 of reduced length compared to conventional molding benches, for example 30 to 70 meters instead of 100 to 150 meters. This molding bench 40 comprises several parallel molds 41 of different sections, mounted on foundations 40 '(cf. Fig. 2 and 3 ). This particular arrangement gives this molding bench 40 a very great flexibility in the production management to simultaneously produce beams 1 of sections and of different lengths. Of course, the number of molds 41 may be different, as well as their section and length. These molds 41 can also be adjustable in width and / or depth by means of movable walls.

The preparation zone A makes it possible to prepare, apart from the molding bench 40, in parallel thereto and at human height, sets of pre-assembled elements 5 extending over the entire length of this bench. Each set of pre-assembled elements 5 corresponds to one of the molds 41 and comprises an arrangement of reinforcing cages 2, formwork spacers 4, anchoring pieces 6 and prestressing cables 3 determined in FIG. function of the beams 1 to manufacture.

This preparation zone A comprises, in the example shown, a frame machine 20 which is a standard machine for automatically manufacturing frames 2a used in the composition of the reinforcement cages 2. These frames 2a are made by folding a wire, for example in the form of a rectangle. This frame machine 20 is fed by a reel 21 carrying four coils 22 of wire of different diameters, for example 6, 8, 10 and 12 mm. Depending on the type of beams 1 to be manufactured, the frame machine 20 will automatically use one or the other diameter of wire to make frames 2a of different dimensions and strength depending on the beams 1 to be manufactured.

The preparation zone A comprises another reel 23 carrying three coils 24 of wire of the same diameter, for example 5 mm. These three son constitute mounting frames 2b used in the composition of the frame cages 2. They are unwound simultaneously and positioned parallel, for example, in a triangle to be welded, by a welding station 25, on three sides of the frames 2a of the same reinforcement cage 2. A conveyor belt 26 arranged between the frame machine 20 and the reel 23 makes it possible to bring the frames 2a towards an operator who grasps the frames 2a one after the other and presents them next to the welding machine 25 (cf. Fig. 4 ). The gaps between the parallel frames 2a of the same reinforcement cage 2 are of course defined for each beam 1 to be manufactured. If the beams 1 to be manufactured have a length less than or equal to 8 meters, for example, a cage will be made of reinforcement 2 by beam 1. If their length is greater than 8 meters, two, or even three, reinforcement cages 2 per beam 1 will be realized.

When a reinforcement cage 2 is completed, it is transferred to a preparation mat 28 by a supply chain 27 (cf. Fig. 4 ). This preparation mat 28 extends parallel over the entire length of the casting bench 40 and receives the reinforcing cages 2 aligned one behind the other, as they are finished, and in the exact order their intended position in the corresponding mold 41. During this operation, the formwork spacers 4 and the anchoring pieces 6 (cf. Fig. 6 ) are interposed between the reinforcing cages 2, their handling being for example carried out by a spreader (not shown) placed at the beginning of the preparation mat 28. Then, prestressing cables 3 are threaded through the reinforcing cages 2 , formwork spacers 4 and anchors 6 along the entire length of the preparation belt 28. The introduction of these prestressing cables 3 can be performed either manually, semi-automatically, or automatically using of a specific machine which is not the subject of the present invention. After the introduction of these prestressing cables 3, a set of pre-assembled elements 5 corresponding to a predetermined mold 41 is obtained. The formwork spacers 4 make it possible to delimit the beams 1 between each other in the same mold 41 and consist, for example, of a perforated metal plate whose number of holes corresponds to the number of prestressing cables 3. The anchoring pieces 6 are used both for transporting said assembly 5, between the preparation A and molding B zones, and for the attachment of the prestressing cables 3 to the traction devices 50, 51 provided on the molding bench 40. example consist of metal combs.

The arrangement of this preparation zone A is designed to allow the operator to work in good ergonomic conditions, the conveyor belt 26 and preparation 28 being located at height of man, and to avoid any handling, the progress of the reinforcement cages 2 being controlled manually by push button, without physical effort.

The set of pre-assembled elements 5 is then conveyed into the appropriate mold 41, in a single operation, by specific gripping means 31 attached to the anchoring pieces 6. These gripping means 31 are suspended from a rudder 30 , the latter being movable in translation along the three axes X, Y, Z on a traveling crane (cf. Fig. 3 and 5 ). These gripping means 31 are arranged to lift in one piece each set of pre-assembled elements 5 by applying a tension to tension the prestressing cables 3, prevent buckling and facilitate its introduction into the mold 41 and that the introduction of said prestressing cables 3 in the traction devices 50, 51 described below. The overhead crane spans the preparation A and B molding zones to allow the gripping means 31 to pass easily from one to the other A, B and C zones.

During this transfer operation, a new set of pre-assembled elements 5 can be prepared in the preparation zone A for filling another mold 41.

When the casting bench 40 is ready, that is to say that the mold or molds 41 are lined with sets of pre-assembled elements 5, the prestressing cables 3 are tensioned by traction devices, commonly called trimmers 50, 51, disposed at the ends of the molds 41 in suitable pits 42 provided in the foundations 40 '(cf. Fig. 6A-6C ). For each mold 41, at least two trimmers 50, 51 are provided: a fixed trimmer 50 and a trimmer 51 movable in rotation about a pivot 52 integral with the foundations 40 'between a rest position (cf. Fig. 6A ) in which it does not exert any traction on the prestressing cables 3 and a working position (cf. Fig. 6B ) in which it exerts a traction on these prestressing cables 3 in the direction of their length. Depending on the width of the molds 41, it is possible to provide trimmers 50, 51 of different width and power. Rooms anchoring 6 sets of pre-assembled elements 5 provided at the ends for locking the prestressing cables 3 in the trimmers 50, 51. These trimmers 50, 51 are designed to allow automatic threading of the prestressing cables 3 by a vertical movement from top to bottom and undoing by reverse movement. They are formed of parallel slats 53, vertical and separated by intervals 54 allowing the introduction of a prestressing cable 3 at intervals 54 (cf. Fig. 6C ). This new design saves a lot of time and automates threading. In comparison, in conventional trimmers, prestressing cables are threaded manually and individually through through holes. When the prestressing cables 3 are placed in the two trimmers 50, 51, the movable trimmers 51 are each moved by a jack 55 of force, articulated at its two ends between a pivot 56 integral with the foundations 40 'and a pivot 57 integral with the trimmers 51. A removable stop 58 makes it possible to limit the stroke of the movable tread 51, this abutment 58 being actuated by another jack 59. The movable trimmers 51 make it possible to achieve a partial tension of the prestressing cables 3, for example 30 at 50% of the total voltage. The final tensioning is carried out unitarily on each prestressing cable 3 by means for example of a monofilar jack.

When all these preparatory operations are completed, the concrete is poured into the molds 41. After hardening of the concrete, the movable trimmers 51 return to their rest position to release the tension on the prestressing cables 3 and the demoulding of the beams 1 can begin . Each mold 41 is demolded in a single operation by the gripping means 31 of the rudder 30 which raises in one piece all the beams 1 and deposited on transport means 60 provided in the discharge zone C. A this effect, handling hooks (not shown) are provided in the upper part of the beams 1 to hook the gripping means 31 of said lifter 30.

The transport means consist, in the example shown, of an evacuation trolley 60 of the same length as the molding bench 40 and placed in parallel, between the molding bench 40 and the preparation mat 28 (cf. Fig. 2 and 3 ). This evacuation trolley 60 is movable longitudinally for example on rails 61. It moves in front of a cutting station 62, where the prestressing cables 3 are cut between the successive beams 1, to separate the beams 1 from each other. the same set. The cutting station 62 may comprise a torch, a circular saw, a chainsaw or any other suitable means. Depending on their length, the beams 1 may be conveyed transversely to an evacuation station 63 or longitudinally to the outside of the building for example, where the beams 1 are stored on a storage area (not shown), either in packets on pallets, either individually depending on their length.

It is clear from this description that the manufacturing method according to the invention and the installation implementing this method can significantly improve both the working conditions of the operators, the productivity of the production tool and the quality. beams 1 manufactured. Indeed, all the painful tasks inherent in traditional manufacturing are removed. The prestressing cables 3 being housed inside the reinforcement cages 2 and pretended during their placement in the molds 41 are not likely to come into contact with the demolding oil covering the bottom and the walls of the molds. molds 41. The manufacture of the reinforcing cages 2 being offset outside the molds 41 and computer-assisted ensures very good accuracy. The absence of risky intervention such as the cutting of the prestressing cables 3 in the molds 41 makes it possible to preserve them and to avoid soiling. Finally, the use of the molds 41 being perfectly optimized since all of the preparation and processing operations of the finished products are carried out outside the molding bench 40, it is occupied only during the pouring of the concrete and hardening. It is therefore possible to perform a maximum number of rotations and to make profitable the financial investment of the facility in an optimal way. Another advantage also lies in the flexibility of the production due to the reduced length of the casting bench 40 and the variety of molds 41 possible. This installation 10 can therefore respond quickly to market demand even for very small series, both for prestressed concrete beams and for reinforced concrete beams.

The present invention is not limited to the embodiment described but extends to any modification and variation obvious to a person skilled in the art while remaining within the scope of protection defined in the appended claims.

Claims (18)

1. A method for manufacturing concrete beams (1) obtained by moulding in a moulding bench (40) comprising at least one mould (41) designed to allow the manufacture of at least one beam (1), characterised in that it comprises at least the following steps, at least one of which is carried out semi-automatically or automatically:

   a) outside the said moulding bench (40) at least one assembly of preassembled elements (5) is prepared, comprising at least reinforcing cages (2) involved in the manufacture of the said beam (1), these elements (2, 3) being positioned with respect to each other at predetermined locations according to the beam (1) to be produced,

   b) this assembly of preassembled elements (5) is picked up in a single block by means of gripping means (31) and it is deposited inside the said mould (41),

   c) the concrete is poured into the said mould (41),

   d) after the concrete has hardened, the said manufactured beam (1) is removed from the mould in a single block using gripping means (31), then,

   e) it is carried away towards a storage area.
2. A method according to Claim 1, in which the moulding bench (40) comprises several moulds (41), each mould (41) being designed to allow the manufacture of a beam assembly (1), characterised in that in the preparation stage (a) and outside the said moulding bench (40), several assemblies of preassembled elements (5) are successively prepared by completing them by formwork spacers (4) to separate the beams (1) of a single assembly from each other, each assembly of preassembled elements is picked up in a single block by means of gripping means (31) in order to deposit it inside each mould (41),
3. A method according to Claim 2, characterised in that it is designed to allow the manufacture of beams (1) having different sections and lengths, the moulds (41) of the said moulding bench (40) having different sections and the formwork spacers (4) of each assembly of preassembled elements (5) being disposed at different intervals.
4. A method according to Claim 2, characterised in that in the preparation stage (a) and outside the said moulding bench (40), the said assemblies of preassembled elements (5) are completed by prestressing cables (3) which are passed inside the reinforcing cages (2) and the formwork spacers (4).
5. A method according to Claim 2, characterised in that in the preparation stage (a) and outside the said moulding bench (40), the said assemblies of prefabricated elements (5) are completed by anchors (6) disposed at least at the ends and designed to allow the displacement of these assemblies under tension by the said gripping means (31) and the automatic threading of the prestressing cables (3) in traction devices (50, 51) of the moulding bench (40).
6. A method according to Claim 1, characterised in that in the preparation stage (a) and outside the said moulding bench (40), the said reinforcing cages (2) are produced at least in a semi-automatic manner.
7. A method according to Claim 2, characterised in that after the concrete has set, each assembly of manufactured beams (1) is removed from the mould in a single block, then it is deposited in an evacuation zone outside the said moulding bench (40).
8. A method according to Claims 4 and 7, characterised in that in the evacuation zone, the prestressing cables (3) are divided between two consecutive formwork spacers (4) to separate the beams (1) of the same assembly before evacuating them towards a storage area.
9. An installation (10) for the manufacture of concrete beams (1), comprising at least one moulding zone (B) provided with a moulding bench (40), characterised in that it comprises at least one preparation zone (A) for at least one assembly of preassembled elements (5) positioned with respect to each other according to each beam (1) to be manufactured and comprising at least reinforcing cages (2) involved in the manufacture of the said beam (1), this preparation zone (A) being disposed outside the said moulding zone (B), and gripping means (31) designed to remove the said assembly of preassembled elements (5) in a single block from the said preparation zone (A) and deposit it in the said moulding bench (40) of the said moulding zone (B), before casting the concrete.
10. An installation (10) according to Claim 9, characterised in that the said preparation zone (A) comprises at least one frame machine (20) designed to automatically produce frames (2a) from metal wires and at least one feeder (23) for metal wires and a welding station (25), both designed to assemble the said frames (2a) by assembly reinforcements (2b) so as to form the said reinforcing cages (2).
11. An installation (10) according to Claim 9, in which the moulding bench (40) comprises several moulds (41) and has an adapted length to produce a beam assembly (1) in each mould (41), characterised in that the said preparation zone (A) comprises at least one preparation belt (28) designed to receive assemblies of preassembled elements (5) comprising at least several reinforcing cages (2) and formwork spacers (4) positioned in mutual relationship at predetermined locations according to each beam assembly (1) to be manufactured in each mould (41).
12. An installation (10) according to Claim 11, characterised in that the said moulding zone (B) comprises traction devices (50, 51) provided at the ends of the said moulds (41) and designed to tension the prestressing cables (3) provided in the said assemblies of preassembled elements (5).
13. An installation (10) according to Claim 12, characterised in that for each mould (41) the traction devices (50, 51) comprise at least one fixed beam (50) and one beam (51) that can rotate around a fixed pivot (52), these beams (50, 51) being formed by ribs (53) that are vertical, parallel and separated by gaps (54) to receive the said prestressing cables (3).
14. An installation (10) according to Claim 9, characterised in that it comprises an evacuation zone (C) for the manufactured beams (1), this evacuation zone (C) being disposed outside the said moulding zone (B) and comprising at least transport means (60) for the said beams (1) towards at least one storage area.
15. An installation (10) according to Claims 11 and 14, characterised in that before casting the concrete, the said gripping means (31) are designed to remove each assembly of preassembled elements (5) from the preparation zone (A) and to deposit it in one of the moulds (41) in the moulding zone (B) and, after the concrete has been cast and has hardened, to remove each manufactured beam assembly (1) in a single block from the mould and to deposit it on the said transport means (60) of the said evacuation zone (C).
16. An installation (10) according to Claims 12 and 15, characterised in that the said gripping means (31) are designed to apply tension to the said assemblies of preassembled elements (5) as they move from the preparation zone (A) to the moulding zone (B) to tighten the prestressing cables (3).
17. An installation (10) according to Claims 12 and 15, characterised in that the said evacuation zone (C) comprises at least one cutting station (62) designed to divide the prestressing cables (3) between the formwork spacers (4) to separate the beams (1) of the same assembly before they are stored.
18. An installation (10) according to Claim 10, characterised in that it comprises at least one automaton designed to control at least the frame machine (20) in an automated manner according to the data relating to the beams (1) to be produced.

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