FR3110615A1 - Fixing device for fixing equipment on a concrete structure - Google Patents

Abstract

The invention relates to a fixing device (1) for fixing equipment (7) to a concrete structure (6), comprising: - a hollow metal profile (2) extending along a longitudinal central line (X), the metal profile (2) being formed in a single piece of metal and having a closed rectangular cross-section, and - a plurality of anchoring studs (3) extending from one side (26) of the metal profile (2). Figure for the abstract: Figure 1

Description

Fixing device for fixing equipment to a concrete structure

FIELD OF THE INVENTION

The invention relates to a fastening device for fastening equipment to a concrete structure, such as a concrete wall, slab or floor.

STATE OF THE ART

Fixing devices are known comprising a fixing rail having a C-shaped cross-section and anchor rods extending from the fixing rail. The fixing rail having a C-shaped section comprises two side walls from which extend two lips defining a longitudinal groove in which hammer screws can be inserted. This fixing device is intended to be embedded in the concrete, so that the fixing rail is flush with the surface of the concrete to be able to fix equipment by means of hammer screws. Examples of such fixing devices are described in the documents DE3531998, EP 2 478 163 A1 and EP3081706.

A disadvantage of these fixing devices is that they can have a low resistance to the forces which can be exerted on the equipment in the longitudinal direction of the fixing rail.

In addition, the fixing rail may also have low resistance to tearing forces which may be exerted on the equipment in a direction perpendicular to the surface of the concrete. Indeed, due to their method of manufacture, some rails are formed from sheets having a small thickness. As a result, tearing forces can cause the two lips to open, which leads to detachment of the equipment.

These two modes of failure are particularly detrimental when the fixing device is installed in a building which must be able to withstand dynamic stresses (in particular earthquakes), such as nuclear power stations for example.

In addition, some equipment must be fixed to the concrete structure by means of several fixing devices. However, fixing by means of several fixing devices can be made difficult in the case where the fixing rails are not perfectly parallel to each other. Indeed, the fixing devices only allow a small transverse adjustment in position of the hammer screw inserted in the groove.

Finally, with such fastening devices, dust or liquids can enter the interior of the rail through the groove and accumulate inside the fastening rail. This is particularly the case when the fixing device is anchored in the ground. For example, when the device is installed in a nuclear power plant, if contaminated water enters the mounting rail, it may be difficult to remove it. Washing products can also penetrate and accumulate in the anchoring channel, which can damage the anchoring device over time.

An object of the invention is to propose a fixing device which allows a better absorption of the forces exerted on the equipment and which avoids the penetration of dust or liquids.

This object is achieved in the context of the present invention, thanks to a fixing device for fixing equipment to a concrete structure, comprising:

- a hollow metal profile extending in a longitudinal direction, the profile being formed in a single single piece of metal and having a cross section of closed rectangular shape, and

- a plurality of anchor studs extending from one side of the metal profile.

Due to the closed rectangular shape of its cross-section, when embedded in concrete, the front face of the metal profile which is flush with the surface of the concrete has no grooves. Thus, once the fixing device is embedded in the concrete, dust or liquids can no longer penetrate through the front face of the profile.

Equipment can be fixed on the front face, for example by means of fasteners allowing blind fixing such as self-drilling screws, self-tapping screws, crimp inserts, expansion bolts, blind rivets or nails. The position of these fasteners relative to the front face of the profile can be adjusted to some extent.

In addition, this method of fixing is resistant to the forces which can be exerted on the equipment in the longitudinal direction of the fixing rail and the tearing forces which can be exerted on the equipment in a direction perpendicular to the surface of the concrete. .

The proposed device may also have the following characteristics:

- the metal profile is formed by hot rolling a single single sheet folded on itself and joined edge to edge by welding;

- The cross section has a width of between 50 and 120 millimeters, for example 60 millimeters, and a height of between 30 and 60 millimeters, for example 40 millimeters;

- the cross section has a square shape having a side having a dimension between 40 and 60 millimeters;

- The metal profile comprises walls having a thickness of between 2.5 and 8 millimeters;

- the metal profile has a first end having a first opening, and a second end, opposite the first end and having a second opening, the fixing device comprising a first end cap adapted to be fixed on the first end to close the first opening and a second end cap adapted to be fixed on the second end to close the second opening;

- each anchor bolt comprises a rod and a head, the rod having a first end fixed to the face of the metal section and a second end, opposite the first end and fixed to the head.

The invention also relates to a method for manufacturing a concrete structure comprising steps of:

- installation of a fixing device as defined above, in a concrete formwork, so that the metal section has a rear face on which the anchoring pins are fixed which is turned towards the inside of the formwork, and a front face, opposite the rear face, facing the outside of the formwork,

- pouring concrete into the formwork so that the concrete surrounds the anchor dowels and partially encases the metal profile, so that the front face of the metal profile is flush with the surface of the poured concrete.

In one mode of implementation of the manufacturing method, several fastening devices are installed in the concrete formwork, the metal sections being arranged parallel to each other.

The metal profiles are preferably positioned at a distance from each other, with a constant distance between a metal profile and the following profile.

The invention also relates to a method for fixing equipment to a concrete structure manufactured in the manner which has just been defined, comprising a step of:

- fix the equipment by means of a fixing device through the front face of the metal section.

The fastener may include a self-drilling screw, self-tapping screw, crimp insert, expansion bolt, blind rivet or nail.

The invention also relates to a concrete structure comprising:

- a concrete matrix,

- metal reinforcement embedded in the concrete matrix, and

- A fixing device as defined above, the fixing device being partially embedded in the concrete matrix so that only one front face of the metal profile is flush with a surface of the concrete matrix.

PRESENTATION OF DRAWINGS

Other characteristics and advantages will emerge from the description which follows, which is purely illustrative and not limiting, and must be read in conjunction with the appended drawings, among which:

- Figures 1 and 2 show schematically, in perspective, a fixing device according to one embodiment of the invention,

- Figure 3 is a cross-sectional view of the fastening device of Figures 1 and 2,

- Figure 4 shows, schematically, the fixing device once it is embedded in a concrete structure,

- Figures 5A to 5C schematically show alternative embodiments of the fastening device in which the metal profile has a cross section of closed rectangular shape,

- Figures 6A to 6D schematically show alternative embodiments of the fastening device in which the metal profile has a cross section of closed square shape,

- Figure 7 schematically shows the positioning of a fixing device in a concrete formwork during the manufacture of a vertical concrete wall,

- Figure 8 shows, schematically, the positioning of a fixing device, in a concrete formwork during the manufacture of a concrete slab, the device being intended to be flush with the upper surface of the slab,

- Figure 9 shows, schematically, in partial section, the positioning of a fixing device, in a concrete formwork during the manufacture of a concrete floor, the device being intended to be flush with the lower surface of the floor,

- Figure 10 shows, schematically, the fixing device, after the pouring of the concrete,

- Figure 11 schematically shows a concrete structure in which several fastening devices have been embedded,

- Figure 12 shows, schematically, equipment fixed to a concrete structure by means of fixing devices.

DETAILED DESCRIPTION OF AN EMBODIMENT

In Figures 1 to 3, the fixing device 1 shown comprises a metal profile 2, a plurality of anchoring studs 3 and end caps 4 and 5.

As illustrated in these figures, the metal profile 2 is a hollow metal profile. The metal profile 2 comprises walls 21 to 24 which surround an internal cavity 29. The walls include a front wall 21, a rear wall 22, a first side wall 23 and a second side wall 24. The side walls 23 and 24 are extend orthogonally with respect to the front wall 21 and the rear wall 22. Each side wall 23 and 24 is connected by a longitudinal edge to the front wall 21 and by another longitudinal edge to the rear wall 22.

The metal profile 2 extends along a longitudinal center line X. In the embodiment illustrated in Figures 1 to 3, the longitudinal center line X is straight. However, in another embodiment, the longitudinal centerline could be curved.

The metal profile 2 has a cross section of closed rectangular shape. The terms "cross section" designate a section of the metal profile taken in a transverse section plane, orthogonal to the longitudinal center line X of the metal profile. The term "closed" means that, in the transverse section plane (i.e. orthogonal to the longitudinal direction), the walls of the metal profile 21 to 24 surround the cavity 29 in a continuous manner, that is to say without interruption of material. . In particular, no longitudinal groove is made through the front wall 21.

The metal profile 2 can be formed in a single single piece of material. For example, the metal profile can be obtained by cold rolling or by hot rolling. Preferably, the metal profile 2 is obtained by hot rolling a single single metal sheet folded on itself and joined edge to edge by a weld line. The metal profile 2 can be formed from non-alloy steel (for example an S355 steel according to standard NF EN 10020, September 2000) or from an alloy steel (for example a stainless steel).

The front wall 21 has a first flat outer face 25 (or front face). The front face 25 is intended to be flush with the surface of the concrete when the device is embedded in a concrete structure. The rear wall 22 has a second flat outer face 26 (or rear face), opposite the first face 25. The side walls 23 and 24 have respective outer side faces 27 and 28. The rear face 26 and the side faces 27 and 28 are intended to be embedded in the concrete of the concrete structure.

The metal profile 2 has a length L (measured along the longitudinal center line X), a width l and a height h (measured in a plane transverse to the longitudinal direction). The width l and the height h are the external dimensions of the rectangular section of the metal profile 2.

In the embodiment illustrated in Figures 1 to 3, the front face 25 and the rear face 26 define the width l of the metal section 2 and the side faces 27 and 28 define the height h of the metal section 2. The height h of the metal profile 2 is less than the width l of metal profile 2.

The metal section has a length L of between 0.3 and 16 meters, preferably between 1 and 10 meters. In an exemplary embodiment, the metal profile has a length of 2100 millimeters.

The cross section of the metal profile 2 has a width l of between 50 and 120 millimeters, and a height h of between 30 and 60 millimeters. In an exemplary embodiment, the cross section of the metal profile 2 has a width of 60 millimeters and a height of 40 millimeters.

The walls 23 to 26 of the metal profile 2 have a thickness e of between 2.5 and 8 millimeters. In an exemplary embodiment, the thickness e of the walls 23 to 26 is approximately 5 millimeters.

The metal profile 2 can be covered with a layer of protective coating, for example a layer of paint or a metal layer (of zinc for example). In the case where the metallic layer is made of zinc, it can be deposited by a galvanizing or electrolytic zinc-plating process or by lamellar non-electrolytic deposition.

The metal section 2 has a first end 41 presenting a first opening 42, and a second end 51, opposite the first end 41 and presenting a second opening 52. The end caps include a first end cap 4 capable of being fixed to the first end 41 to close the first opening 42 and a second end plug 5 capable of being fixed to the second end 51 to close the second opening 52. The end plugs 4 and 5 make it possible to prevent concrete penetrates inside the cavity 29 during the pouring of the concrete. End caps 4 and 5 can be formed from metal or plastic.

In the example illustrated in Figures 1 to 3, the fixing device 1 comprises four anchoring studs 3. However, the fixing device 1 can comprise a different number of anchoring studs 3 depending on the needs and the length of the metal profile 2. The anchoring studs 3 are fixed to the rear wall 22 of the metal profile 2, for example by a method of welding metal studs with electric arc.

Each anchor bolt 3 comprises a rod 31 and a head 32. The rod 31 has a first end 33 fixed to the rear face 26 of the metal section 2 and a second end 34 fixed to the head 32. The rod 31 of each anchor anchor 3 extends perpendicular to the rear face 26 of the metal profile 2, that is to say in a direction orthogonal to the longitudinal center line X of the metal profile 2.

In the embodiment illustrated in Figures 1 to 3, each anchor pin 3 is an SD type anchor pin according to standard NF EN ISO 13918 (January 2018). The rod 31 has a cylindrical shape of revolution and the head 32 also has a cylindrical shape of revolution. However, the head 32 has a diameter greater than the diameter of the rod 31. In this way, the head forms a bulge at the end of the rod, which promotes anchoring of the fixing device 1 in the concrete.

Figure 4 schematically illustrates the fixing device 1 once it is embedded in a concrete structure 6.

The concrete structure 6 comprises metal reinforcements 61 and a concrete matrix 62. The metal reinforcements 61 are embedded in the concrete matrix 62. As illustrated in Figure 4, the fixing device 1 is embedded in the concrete matrix 62 so that the front face 25 is flush with an outer surface 63 of the concrete structure 6. In other words, the front face 25 is not in contact with the concrete. The front face 25 is in contact with the ambient air. Cavity 29 contains no concrete. Conversely, the rear face 26 and the side faces 27 and 28 are covered with concrete. The anchoring studs 3, embedded in the concrete, make it possible to anchor the fixing device 1 in the concrete matrix 62.

As can be seen in FIG. 4, the dimensions and the position of the metal profile 2 have been chosen so as to fit into the thickness E of the reinforced concrete cover (distance between the surface of the metal reinforcement 61 ( pins, stirrups and frames included, as well as skin reinforcement, if any) closest to the outer surface 63 of the concrete). The minimum coating thickness E is typically equal to 40 to 50 millimetres.

FIGS. 5A to 5C schematically represent alternative embodiments of the fixing device 1 in which the metal profile 2 has a cross section of closed rectangular shape. In these variants, the metal profile 2 is identical to the metal profile 2 of the fixing device of Figures 1 to 3.

In FIG. 5A, the fixing device 1 comprises anchor studs 3, each anchor stud 3 comprising a profile having a T-shaped cross-section. The profile comprises a core forming the rod 31 and a single welded wing at the end of the rod 31 and forming the head 32.

In FIG. 5B, the fixing device 1 comprises anchoring studs 3, each anchoring stud 3 comprising a profile having an I-shaped cross-section. The profile comprises a core forming the rod 31 and two flanges welded to the ends of the core, one of the wings forming the head 32.

In FIG. 5C, the fixing device 2 comprises anchor studs 3, each anchor stud 3 comprising a threaded rod 31 and a flared head 32.

FIGS. 6A to 6D schematically represent alternative embodiments of the fixing device 1 in which the metal profile 3 has a cross section of closed square shape.

The square-shaped cross-section has one side having a dimension c of between 40 and 60 millimeters. The walls 25 to 28 of the metal profile 2 have a thickness e of between 2 and 8 millimeters. In an exemplary embodiment, the dimension of the side c of the cross section of the metal profile 2 is 40 millimeters and a height of 40 millimeters, and the thickness e of the walls is 5 millimeters.

In FIG. 6A, the fixing device 1 comprises anchoring studs 3, each anchoring stud 3 comprising a rod 31 of cylindrical shape of revolution and a head 32 also having a cylindrical shape of revolution. Anchor studs 3 can be SD type anchor studs.

In FIG. 6B, the fixing device 1 comprises anchoring studs 3, each anchoring stud 3 comprising a rod 31 formed of a profile having a T-shaped cross-section. The profile comprises a core forming the rod 31 and a single wing welded to the end of the rod 31 and forming the head 32.

In FIG. 6C, the fixing device 1 comprises anchoring studs 3, each anchoring stud 3 comprising a rod 31 formed of a profile having an I-shaped cross-section. The profile comprises a web forming the rod 31 and two wings welded to the ends of the core, one of the wings forming the head 32 (two wings in all: one wing welded to each end of the core).

In FIG. 6D, the fixing device 1 comprises anchor studs 3, each anchor stud 3 comprising a threaded rod 31 and a flared head 32.

During the manufacture of a concrete structure 6, the fixing device 1 is installed in a concrete formwork, so that the rear face 26 of the metal section 2 is turned towards the inside of the formwork while the front face 25 of the metal profile 2 is turned towards the outside of the formwork.

Figure 7 schematically shows the positioning of a fixing device 1, in a concrete formwork 7, during the manufacture of a vertical concrete wall. The front face 25 of the metal section 2 is positioned against the formwork wall 71 vertical. The anchor bolts 3 are oriented horizontally towards the inside of the formwork. The anchoring studs 3 extend from the rear face 26 of the metal section 2 in the direction of the metal reinforcements 61 arranged in a trellis in the formwork.

The concrete is then poured into the formwork 7 so that the concrete coats the anchoring studs 3 and partially coats the metal profile 2, and coats the metal reinforcements 61. Because it is in contact with the wall 71 of the formwork , the front face 25 of the metal profile 2 is not covered with concrete.

Thanks to the presence of the end plugs 4 and 5, the concrete cannot penetrate inside the metal profile 2 through the end openings 42 and 52.

Once the concrete has hardened, the formwork 7 is removed. The front face 25 of the metal profile 2 appears on the vertical surface of the formed concrete wall.

Several identical fixing devices 1 can be installed in the concrete formwork 7. Typically, the metal profiles 2 of the fixing devices 1 are arranged parallel to each other.

Figure 8 schematically shows the positioning of a fixing device 1 in a concrete formwork 7 during the manufacture of a concrete slab.

The fixing device 1 is installed in the concrete formwork 7, above the metal reinforcements 61. The front face 25 of the metal profile 2 is positioned upwards while the rear face 26 is positioned downwards. The anchor studs 3 extend vertically between the metal reinforcements 61.

The concrete is then poured into the formwork 7 so that the concrete coats the anchor studs 3 and partially coats the metal profile 2, and coats the metal reinforcements 61. The concrete formwork 7 is filled to a level such that the front face 25 of the metal profile 2 is flush with the upper surface of the concrete.

Thanks to the presence of the end plugs 4 and 5, the concrete cannot penetrate inside the metal profile 2 through the end openings 42 and 52.

Once the concrete has hardened, the formwork 7 is removed. The front face 25 of the metal profile 2 appears on the upper horizontal surface of the concrete slab.

Figure 9 schematically shows the positioning of a fixing device 1 in a concrete formwork 7 during the manufacture of a concrete floor.

The fixing device 1 is installed in the concrete formwork 7, below the metal reinforcements 61. The front face 25 of the metal section 2 is positioned downwards against the horizontal formwork wall 71 . The rear face 26 of the profile 2 is positioned upwards. The anchor studs 3 extend vertically between the metal reinforcements.

The concrete is then poured into the formwork 7 so that the concrete coats the anchoring studs 3 and partially coats the metal profile 2, and coats the metal reinforcements 61. The front face 25 of the metal profile 2 is not covered with concrete.

Thanks to the presence of the end plugs 4 and 5, the concrete cannot penetrate inside the metal profile 2 through the end openings 42 and 52.

Once the concrete has hardened, the formwork 7 is removed. The front face 25 of the metal profile 2 appears on the lower horizontal surface of the formed concrete slab.

FIG. 10 represents, schematically, in partial section, a fixing device, 1 after the pouring of the concrete. The front face 25 of the metal profile 2 is visible on the surface 63 of the concrete structure 62.

FIG. 11 schematically represents a concrete structure 6 in which several fastening devices 1 have been embedded. As can be seen in this figure, the metal sections 2 the fastening devices 1 are positioned parallel to each other others and with a constant distance between a metal profile and the following metal profile (for example a distance of 0.5 meter between two successive profiles 2).

Alternatively, it would also be possible to arrange additional fixing devices 1 perpendicular to the parallel fixing devices, so as to form a grid.

Thanks to the fastening devices 1, it is possible to fix equipment on the concrete structure 6. For this purpose, the equipment is fixed by means of fasteners through the front faces of the metal profiles. Depending on the case, the fasteners may include self-drilling screws, self-tapping screws, crimp inserts, expansion bolts, blind rivets or nails. It may be necessary to drill holes through the front wall of the profiles to be able to insert the fasteners. The position of the holes can be adjusted according to the dimensions of the equipment to be fixed.

FIG. 12 schematically represents equipment 7 fixed to a concrete structure 6 by means of fastening devices 1. In this example, the equipment 7 is supports for electric cables or fluid circulation pipes.

However, fasteners 1 can be used to secure other equipment such as ventilation ducts, cable trays, pipe trays, electrical cabinets, cladding and facade framing systems.

Such fastening devices 1 can be used in all types of works, for example in industrial buildings, tunnels, bridges as well as galleries and shafts.

Claims (13)

Fixing device (1) for fixing equipment (7) to a concrete structure (6), comprising:
- a hollow metal profile (2) extending along a longitudinal center line (X), the metal profile (2) being formed in a single single piece of metal and having a closed rectangular cross-section, and
- a plurality of anchor bolts (3) extending from one face (26) of the metal profile (2). Fastening device according to claim 1, in which the metal profile (2) is formed by hot rolling a single single sheet folded over on itself and joined edge to edge by welding. Fastening device according to one of Claims 1 and 2, in which the cross-section has a width (l) of between 50 and 120 millimeters, for example 60 millimeters, and a height (h) of between 30 and 60 millimeters, for example 40 millimeters. Fixing device according to one of Claims 1 to 3, in which the cross section has a square shape with one side having a dimension (c) of between 40 and 60 millimetres. Fixing device according to one of Claims 1 to 4, in which the metal profile (2) comprises walls (21-24) having a thickness (e) of between 2.5 and 8 millimeters. Fixing device according to one of Claims 1 to 5, in which the metal profile (2) has a first end (41) presenting a first opening (42), and a second end (51), opposite the first end ( 41) and having a second opening (52), the fastening device (1) comprising a first end cap (4) able to be fixed on the first end (41) to close off the first opening (42) and a second end plug (5) adapted to be fixed on the second end (51) to close the second opening (52). Fastening device according to one of Claims 1 to 6, in which each anchor bolt (3) comprises a rod (31) and a head (32), the rod (31) having a first end (33) fixed to the face (26) of the metal section (2) and a second end (34), opposite the first end (33) and fixed to the head (32). Method of manufacturing a concrete structure (6) comprising steps of:
- installation of a fixing device (1) according to one of claims 1 to 7, in a concrete formwork (7), so that the metal profile (2) has a rear face (26) on which are fixed the anchoring studs (3) which faces the inside of the formwork (7), and a front face (25), opposite the rear face (26), facing the outside of the formwork (7),
- pouring concrete into the formwork (7) so that the concrete coats the anchor bolts (3) and partially coats the metal profile (2), so that the front face (25) of the metal profile (2) is flush the poured concrete surface. Production method according to Claim 8, in which several fixing devices (1) are installed in the concrete formwork (7), the metal sections (2) of the fixing devices (1) being arranged parallel to one another. Manufacturing method according to claim 9, in which the metal profiles (2) are positioned at a distance from each other, with a constant distance between a metal profile and the following profile. Method for attaching equipment to a concrete structure manufactured according to a manufacturing method in accordance with one of Claims 8 to 10, comprising a step of:
- fix the equipment (7) by means of a fixing device through the front face (25) of the metal section (2). A method of fastening according to claim 11, wherein the fastening member comprises a self-drilling screw, a self-tapping screw, a crimp insert, an expansion bolt, a blind rivet or a nail. Concrete structure (6) comprising:
- a concrete matrix (62),
- metal reinforcements (61) embedded in the concrete matrix (62), and
- a fixing device (1) according to one of claims 1 to 7, the fixing device (1) being partially embedded in the concrete matrix (62) so that only a front face (25) of the metal profile (2) is flush with a surface (63) of the concrete matrix (62).