Beam for forming a horizontal formwork floor, formwork equipment and associated process

Abstract

A beam (2) for forming a horizontal formwork floor, the beam (2) comprising a bottom flange (3), a top flange (5) configured to support a formwork wall, and a stiffening element (4) connecting the bottom flange (3) to the top flange (5), the stiffening element (4) comprising a main cylinder (40) defining, in cross-section, a closed ring and at least one auxiliary cylinder (41a, 41b, 41c, 41d) of triangular cross-section connecting the main cylinder (40) to the bottom flange (3) or to the top flange (5). Figure 7

Description

Title of the invention: Beam for forming a horizontal formwork floor, formwork equipment and associated method. Technical field

[0001] The present invention relates to the field of construction, in particular, formwork. The present invention relates more particularly to a beam intended to form a horizontal formwork floor.

[0002] To form a horizontal slab in a building, it is known to pour concrete onto a horizontal formwork floor. With reference to [Fig. 1], a formwork system 110 is shown by way of example, comprising a horizontal formwork floor P supported by a vertical structure 107 comprising vertical props. The horizontal formwork floor P includes, as is known, a plurality of beams 101, called "primary beams," which are mounted at the upper ends of the vertical props. The horizontal formwork floor P further includes a plurality of beams 102, called "secondary beams," which rest on the beams 101. A formwork skin 106, also called "formwork skin," is fixed to the upper surface of the beams 102 so as to form a formwork surface.As a general rule, the formwork wall 106 is in the form of a wooden plywood plate which is nailed into an upper surface of the joists 102.

[0003] A beam 102 is a major element of a horizontal formwork floor P. In order to avoid the operator falling through the network of beams 102 when fixing the formwork wall 106, it is preferable to have a large number of beams 102 with a reduced spacing between them (generally less than or equal to 13cm). The disadvantage of a high number of beams 102 is that it significantly increases the number of beam 102 handling operations for one operator for the same formwork wall area 106. To install a beam 102, an operator positioned at the bearing surface of the vertical props 107 must lift the beam 102 and position it on the beam 101. Consequently, the mass of a beam 102 is an important criterion for reducing the physical strain on operators.One solution to reduce mass would be to reduce the thickness of the walls of beam 102, which is generally made of wood or aluminum. Such a reduction in thickness has the disadvantage of affecting mechanical resistance, in particular, to buckling or sagging of the slender (thin and elongated) walls of beam 102.

[0004] It also follows that the number of beams to be installed is an important criterion in order to reduce physical strain and maintain satisfactory productivity. A solution To reduce the number of beams required for a given formwork area, the width of the beams can be increased. This also reduces the risk of tipping when the operator walks on it, by increasing the beam's stability.

[0005] With reference to [Fig. 2], a cross-sectional view of a first type of beam 102a according to the prior art is shown. The beam 102a has a lower flange 130 configured to bear on a beam. The lower flange 130 has projecting lateral ends forming connecting tongues 131 with the beam. The beam 102a has an upper flange 150 configured to bear on a formwork wall. In this example, the upper flange 150 has two separate parts providing an upper recess 160 in which a piece of wood 161, for example, a cleat, is mounted. Such a piece of wood 161 allows the formwork wall to be fixed by nailing it into the piece of wood 161. The mechanical strength of the beam 102a is thus not affected by the fixing of the formwork wall.The lower flange 130 is connected to the upper flange 150 by a stiffening body 140 defining a closed belt. In this example, the stiffening body 140 comprises a lower horizontal wall 141, formed by the lower flange 130, an upper horizontal wall 142, delimiting the upper housing 160, and two lateral vertical walls 143.

[0006] The vertical side walls 143 are high and must be thick in order to have high mechanical strength to resist buckling forces. Also, such a beam 102a has a high mass, which presents a disadvantage.

[0007] The vertical side walls 143 are widely spaced to increase the width of the beam 102a and limit the length of the free edges of the flanges 130, 150. The horizontal walls 141, 142 are thickened to ensure sufficient lateral support of the vertical side walls 143.

[0008] To eliminate these drawbacks, with reference to [Fig. 3], a cross-sectional view of a second type of beam 102b according to the prior art is shown. Similar to the previous example, the beam 102b has a bottom flange 130 configured to bear on a beam. The bottom flange 130 has projecting lateral ends forming connecting tabs 131 with the beam. In [Fig. 3], the beam 102b has a bottom flange 130 in two parts. The beam 102b has a top flange 150, similar to that of the first type of beam 102a, configured to bear on a formwork wall.

[0009] Still referring to [Fig. 3], the lower flange 130 is connected to the upper flange 150 by a stiffening body 140 defining a closed ring. In this example, the stiffening body 140 has a narrower width than the beam 102b in order to reduce its mass. The stiffening body 140 comprises: • a lower horizontal wall 141 separated from the lower sole 130 by substantially vertical brackets 145, • a horizontal upper wall 142, delimiting the upper housing 160, • two curved side walls 143.

[0010] The curved shape makes it possible to obtain a beam 102b of significant width while limiting the length of the free edges of the footings 130, 150 and the length of the horizontal walls 141, 142, which makes it possible to limit their thickness.

[0011] Such a second type of beam 102b has the advantage of having thinner walls than the first type of beam 102a, which reduces its mass. The curved side walls 143 negatively affect the mechanical resistance to buckling forces, in particular, due to their concavity. This drawback limits the possibility of designing beams with a large width for a given height and thickness. This would require increasing the concavity of the curved side walls 143, thus making the beam more susceptible to buckling.

[0012] The invention thus aims to eliminate at least some of these drawbacks. PRESENTATION OF THE INVENTION

[0013] The invention relates to a beam for forming a horizontal formwork floor, the beam extending longitudinally along a beam axis, the beam comprising a lower flange, an upper flange configured to support a formwork wall and a stiffening body connecting the lower flange to the upper flange, the stiffening body comprising: • a main cylinder defining, in cross-section, a closed belt and • At least one auxiliary cylinder with a triangular cross-section connecting the main cylinder to the lower or upper base plate.

[0014] The use of an auxiliary cylinder, i.e., a cylinder with a triangular cross-section, makes it possible to form a truss that reinforces the main cylinder, whose shape and cross-section can be reduced to lighten the mass of the beam without affecting its mechanical strength. The beam is thus easier for operators to handle. Furthermore, this allows for the design of wider and more stable beams without significantly increasing their mass. Safety is therefore enhanced while keeping the mass down.

[0015] According to one aspect, the stiffening body comprises at least one lower auxiliary cylinder connecting the main cylinder to the lower flange and at least one upper auxiliary cylinder connecting the main cylinder to the upper flange. This allows the reinforcement to be distributed at each flange.

[0016] According to one aspect, the stiffening body comprises at least two lower auxiliary cylinders connecting the main cylinder to the lower flange. This is particularly advantageous when the lower flange has two lateral parts spaced apart from each other.

[0017] According to one aspect, the stiffening body comprises at least two upper auxiliary cylinders connecting the main cylinder to the upper flange. This is particularly advantageous when the upper flange has two lateral parts spaced apart from each other.

[0018] According to one aspect, the beam having an upper housing configured to receive a piece of wood in order to allow the fixing of the formwork wall to the beam, the upper housing opening onto the upper flange.

[0019] According to one aspect, the main cylinder has an upper wall delimiting the upper housing.

[0020] According to one aspect, the main cylinder comprising a lower wall delimiting the lower housing.

[0021] According to one aspect, the upper sole comprises two lateral parts separated from each other.

[0022] According to one aspect, each lateral part of the upper sole is connected to the main cylinder by an upper auxiliary cylinder.

[0023] According to one aspect, the beam has a lower housing, the lower housing opening onto the lower flange.

[0024] According to one aspect, the main cylinder having corners, at least one auxiliary cylinder is connected to the main cylinder by a corner. According to another aspect, each auxiliary cylinder is connected to the main cylinder by a corner. This results in a beam that is uniformly reinforced.

[0025] According to one aspect, the lower sole comprises two lateral parts separated from each other.

[0026] According to one aspect, each lateral part of the lower sole is connected to the main cylinder by a lower auxiliary cylinder.

[0027] According to one aspect, the main cylinder has two straight vertical side walls. The use of straight vertical side walls increases buckling resistance. The use of auxiliary cylinders reduces the thickness of the straight vertical side walls.

[0028] According to one aspect, each straight vertical side wall having a wall height, the beam having a beam height, the ratio of the wall height to the beam height is between 0.2 and 0.8, preferably between 0.4 and 0.6. This makes it possible to improve the resistance to buckling while reducing the mass of the main cylinder.

[0029] According to one aspect, the beam has a beam width of between 50mm and 200mm, preferably between 65mm and 130mm.

[0030] According to one aspect, the beam having a beam width, the main cylinder has a width less than the width of the beam.

[0031] Also presented is formwork equipment comprising a plurality of beams mounted on a vertical structure and a plurality of joists, as previously presented, positioned on the beams to form a horizontal formwork floor.

[0032] According to one aspect, the formwork equipment includes at least one formwork wall fixed to the beams.

[0033] A method for assembling formwork equipment as described above is also presented, the method comprising steps consisting of: • Mounting a plurality of beams on a vertical structure • Position a plurality of joists on the beams to form a horizontal formwork floor. PRESENTATION OF THE FIGURES

[0034] The invention will be better understood upon reading the following description, given by way of example, and referring to the following figures, given by way of non-limiting examples, in which identical references are given to similar objects.

[0035] Fig. 1 is a schematic representation of a formwork equipment according to the prior art.

[0036] Fig. 2 is a schematic representation of a first type of beam according to the prior art in a cross-sectional view.

[0037] Fig. 3 is a schematic representation of a second type of beam according to the prior art in a cross-sectional view.

[0038] Fig. 4 is a schematic representation of formwork equipment according to one embodiment of the invention.

[0039] Fig. 5 is a schematic representation of an arrangement of beams seen from above.

[0040] Fig. 6 is a schematic perspective representation of a beam according to one embodiment of the invention.

[0041] Fig. 7 is a representation of the beam of Fig. 6 according to a cross-sectional view.

[0042] Fig. 8 is another representation of the beam of Fig. 6 according to a cross-sectional view.

[0043] The [Fig.9] is a second embodiment of a beam.

[0044] The [Fig. 10] is a third embodiment of a beam.

[0045] It should be noted that the figures set out the invention in detail to implement the invention, said figures being of course able to serve to better define the invention where appropriate. DETAILED DESCRIPTION OF THE INVENTION

[0046] The invention will be presented for a beam to form a horizontal formwork floor. With reference to [Fig.4], a formwork equipment 10 is schematically represented comprising a plurality of beams 1 mounted on a vertical structure 7 and a plurality of beams 2 positioned on the beams 1 to form a horizontal formwork floor P.

[0047] Indeed, as previously stated, the horizontal formwork floor P comprises, in a known manner, a plurality of beams 1, called "primary beams," which are mounted at the upper ends of a vertical structure 7, for example, a plurality of vertical props. The horizontal formwork floor P further comprises a plurality of joists 2, called "secondary beams," which rest on the beams 1. A formwork wall 6, also called a "formwork skin," is fixed to the upper surface of the joists 2 so as to form a formwork surface. Typically, the formwork wall 6 is in the form of a sheet of plywood that is nailed to an upper surface of the joists 2.

[0048] It goes without saying that a beam 2 could be directly connected to a vertical structure 7, for example, to a fork of a prop.

[0049] With reference to [Fig. 4], the beams 2 extend parallel to a longitudinal axis while the beams 1 extend parallel to a lateral axis. As illustrated in [Fig. 5], the beams 2 are mounted side-by-side and are mounted adjacent at their ends so as to ensure an optimal spacing E which corresponds to the width of the beam 2 as will be shown later.

[0050] Beam 2

[0051] The structure of a beam 2 will henceforth be presented with reference to Figures 6 to 8. As illustrated in [Fig. 6], the beam 2 extends longitudinally along a beam axis X. Hereafter, the beam 2 will be presented in a coordinate system (X, Y, Z) in which the X axis extends longitudinally, the Y axis extends laterally, and the Z axis extends vertically. The beam 2 thus has a length L2 defined along the X axis, a width E2 defined along the Y axis, and a height H2 defined along the Z axis.

[0052] Preferably, beam 2 has a beam width E2 of between 50 mm and 200 mm, preferably between 65 mm and 130 mm. Preferably, beam 2 has a beam length L2 of between 1 m and 6 m. Preferably, between 1.5 m and 4 m. Preferably, beam 2 has a beam height H2 between 50 mm and 300 mm, preferably between 75 mm and 200 mm.

[0053] Preferably, the beam 2 is made of metal, in particular aluminum. It goes without saying that it could also be made of plastic. Preferably, the beam 2 has walls with a thickness between 1.2 mm and 8 mm.

[0054] Still with reference to [Fig.6], the beam 2 comprises a lower flange 3, an upper flange 5 configured to support a formwork wall 6 and a stiffening body 4 connecting the lower flange 3 to the upper flange 5.

[0055] Lower sole 3

[0056] In this embodiment, with reference to [Fig. 7], the bottom flange 3 comprises two lateral portions 3a, 3b set apart from each other. In particular, the beam 2 includes a lower recess 54 to allow, among other things, the installation of a clamping or suspension device. The lower recess 54 opens onto the bottom flange 3, specifically between the lateral portions 3a, 3b of the bottom flange 3.

[0057] In this example, each lateral part 3a, 3b of the bottom flange 3 has an external connecting tongue 31 that extends laterally outwards. Such an external connecting tongue 31 ensures optimal connection to a beam 1 by means of a clamping device. Preferably, the end of each external connecting tongue 31 is thickened to reinforce the outer longitudinal edges of the beam 2. This prevents deformation in the event of a fall of the beam 2 and also prevents the beams 2 from overlapping when they are positioned side by side as illustrated in [Fig. 5].

[0058] In this example, each lateral portion 3a, 3b of the lower sole 3 has an internal connecting tongue 32 that extends laterally inward. Such an internal connecting tongue 32 ensures optimal connection of accessories in the lower housing 54.

[0059] It goes without saying that the lower sole 3 could be formed from a single part.

[0060] Upper sole 5

[0061] In this embodiment, with reference to [Fig. 7], the top flange 5 comprises two lateral portions 5c, 5d separated from each other. In particular, the beam 2 includes an upper recess 51 configured to receive a piece of wood 52 to allow the formwork wall 6 to be fixed to the beam 2. The upper recess 51 opens onto the top flange 5, in particular, between the lateral portions 5c, 5d of the top flange 5.

[0062] The upper housing 51 opens onto the upper base 5 via a slot whose width E51 ([Fig.8]) is preferably at least 20 mm to allow easy fixing of the formwork wall 6, in particular by nailing. Preferably, the upper housing 51 is configured to receive a piece of wood 52 having a height greater than 15 mm.

[0063] In this example, each lateral portion 5c, 5d of the top flange 5 has an external connecting tongue 53 that extends laterally outwards. The end of each external connecting tongue 53 is thickened to reinforce the outer longitudinal edges of the beam 2.

[0064] This allows, on the one hand, for the structural integrity to be avoided in the event of a fall of beam 2 and strapping during transport by truck and, on the other hand, for the overlapping of beams 2 when they are positioned side by side. Beam 2 thus has a very robust structure.

[0065] It goes without saying that the upper sole 5 could be formed from a single part.

[0066] It goes without saying that a lower sole 3 and / or an upper sole 5 could be integrated directly into the main cylinder 4.

[0067] Stiffening body 4

[0068] According to the invention, with reference to [Fig. 7], the stiffening body 4 comprises a main cylinder 40 defining, in cross-section, a closed belt. Such a main cylinder 40 mechanically reinforces the beam 2. In this example, the main cylinder 40 has a square cross-section to reduce mass, but it could be rectangular.

[0069] In this example, the main cylinder 40 comprises a lower horizontal wall 401, an upper horizontal wall 402, and two straight vertical side walls 403. The use of straight vertical side walls 403 provides better mechanical resistance to buckling forces than a curved wall. The main cylinder 40 has walls 401, 402, and 403 with a thickness between 1.2 mm and 8 mm.

[0070] With reference to [Fig.7], the main cylinder 40 includes an upper wall 402 delimiting the upper housing 51. Similarly, the main cylinder 40 includes a lower wall 401 delimiting the lower housing 54.

[0071] With reference to [Fig.8], each straight vertical side wall 403 has a wall height H40. The horizontal walls 401, 402 each have a length which corresponds to the width E40 of the main cylinder 40.

[0072] Preferably, the ratio of the wall height H40 to the beam height H2 is between 0.2 and 0.8, preferably between 0.4 and 0.6. Thus, the wall height H40 is small compared to the beam height H2, which makes it possible to significantly reduce the mass while maintaining strength optimal mechanics due to the straight vertical side walls 403. Preferably, the main cylinder 40 has a width E40 smaller than the width of the beam E2.

[0073] According to the invention, with reference to [Fig. 7], the stiffening body 4 comprises auxiliary cylinders 41a, 41b, 41c, 41d, having a triangular cross-section, connecting the main cylinder 40 to the lower flange 3 and the upper flange 5. An auxiliary cylinder 41a, 41b, 41c, 41d having a triangular cross-section allows the formation of a truss that is optimal for resisting mechanical stresses. The auxiliary cylinders 41a, 41b, 41c, 41d make it possible to reduce the length of the tongues 31, 53 while forming a beam of significant width. By positioning an auxiliary cylinder at each end of the vertical straight side walls 403, it is possible to reduce the height of the vertical straight side walls 403 and therefore their susceptibility to buckling without increasing their thickness. As is known, resistance to buckling is inversely proportional to the square of the buckling height.

[0074] Preferably, an auxiliary cylinder 41a, 41b, 41c, 41d has walls with a thickness between 1.2 and 8mm.

[0075] In detail, with reference to [Fig. 7], each lateral part 3a, 3b of the lower sole 3 is connected to the main cylinder 40 by a lower auxiliary cylinder 41a, 41b. Similarly, each lateral part 5c, 5d of the upper sole 5 is connected to the main cylinder 40 by an upper auxiliary cylinder 41c, 41d.

[0076] Preferably, the main cylinder 40 comprises four corners, and each auxiliary cylinder 41a, 41b, 41c, 41d is connected to the main cylinder 40 by a corner. Preferably, each auxiliary cylinder 41a, 41b, 41c, 41d has a wall extending in line with a straight vertical side wall 403 so as to reinforce the mechanical structure.

[0077] Thanks to the invention, a beam 2 of reduced mass and improved mechanical resistance is advantageously obtained.

[0078] With reference to [Fig. 9], a second embodiment of a beam 2 with different dimensions is shown. Furthermore, the beam 2 includes stiffening elements along its length X, in particular, ribs 7. In this example, the ribs 7 are formed on the main cylinder 40, in particular, on the lower horizontal wall 401 and on the upper horizontal wall 402.

[0079] With reference to [Fig. 10], a third embodiment of a beam 2 with different dimensions is shown. In this third embodiment, the auxiliary cylinders 41a, 41b, 41c, 41d are connected to the main cylinder 40 indirectly via bridges 8.

[0080] Assembly method

[0081] With reference to [Fig.4], an example of the implementation of a method for assembling formwork equipment 10 will be presented, the method comprising a step of mounting a plurality of beams 1 on the vertical structure 7. Preferably, the main structure 7 is equipped with forks to support the beams 1. The beams 1 are preferably spaced parallel to each other.

[0082] The method includes a step of positioning a plurality of beams 2 on the beams 1 to form a horizontal formwork floor P. As illustrated in [Fig. 5], the beams 2 are arranged so that they are spaced apart in a parallel fashion. In particular, two rows of beams 2 cooperate by their ends, which are in contact, without any risk of overlap.

[0083] The process includes a step consisting of fixing formwork walls 6 onto the beams 2, in particular by nailing.

[0084] Once the horizontal formwork floor P is installed, liquid or pasty concrete can be deposited on the formwork walls in order to form a concrete slab.

Claims

Demands

1. Beam (2) for forming a horizontal formwork floor (P), the beam (2) extending longitudinally along a beam axis (X), the beam (2) comprising a bottom flange (3), a top flange (5) having two lateral portions (5c, 5d) separated from each other to support a formwork wall (6), each lateral portion (5c, 5d) of the top flange (5) having an external connecting tongue (53) extending laterally outwards, and a stiffening body (4) connecting the bottom flange (3) to the top flange (5), the stiffening body (4) comprising: • a main cylinder (40) defining, in cross-section, a closed ring and • At least one lower auxiliary cylinder (41a, 41b) of triangular cross-section connecting the main cylinder (40) to the bottom flange (3) and at least one upper auxiliary cylinder (41c,41d) of triangular section connecting the main cylinder (40) to the upper sole (5).

2. Beam (2) according to claim 1 in which the stiffening body (4) comprises at least two lower auxiliary cylinders (41a, 41b) connecting the main cylinder (40) to the lower flange (3).

3. Beam (2) according to any one of claims 1 to 2 in which the stiffening body (4) comprises at least two upper auxiliary cylinders (41c, 41d) connecting the main cylinder (40) to the upper flange (5).

4. Beam (2) according to any one of claims 1 to 3 comprising an upper housing (51) configured to receive a piece of wood (52) to allow the fixing of the formwork wall (6) to the beam (2), the upper housing (51) opening onto the upper flange (5).

5. Beam (2) according to any one of claims 1 to 4 in which each lateral part (5c, 5d) of the upper flange (5) is connected to the main cylinder (40) by an upper auxiliary cylinder (41c, 41d).

6. Beam (2) according to any one of claims 1 to 5 wherein, the main cylinder (40) having corners, at least one cylinder auxiliary (41a, 41b, 41c, 41d) is connected to the main cylinder (40) by a wedge, preferably, each auxiliary cylinder (41a, 41b, 41c, 41d) is connected to the main cylinder (40) by a wedge.

7. Beam (2) according to any one of claims 1 to 6 wherein the main cylinder (40) has two straight vertical side walls (403).

8. Beam (2) according to claim 7 wherein each straight vertical side wall (403) having a wall height (H40), the beam (2) having a beam height (H2), the ratio of the wall height (H40) to the beam height (H2) is between 0.2 and 0.8, preferably between 0.4 and 0.

6.

9. Formwork equipment (10) comprising a plurality of beams (1) mounted on a vertical structure (7) and a plurality of joists (2) according to any one of claims 1 to 8 positioned on the beams (1) to form a horizontal formwork floor (P).

10. Method of assembling formwork equipment (10) according to claim 9, the method comprising steps of: • Mounting a plurality of beams (1) on a vertical structure (7) • Positioning a plurality of joists (2) on the beams (1) to form a horizontal formwork floor (P).

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