Fixing device for a reinforcing mesh to support a guardrail post

Abstract

A base-forming device for a post (6), configured to be fixed to a reinforcement mesh (5), the device comprising a first bar (1) extending along a first axis (X1), a perpendicular threaded rod (4) fixed to the first bar at its midpoint, a second bar (2), the second bar having in its midpoint a passage or orifice (24) to allow passage for the threaded rod, a clamping element (3), for example a screw cross, comprising a tube (32), a nut (31) fixed to a longitudinal end of the tube, and arms (33, 34), the clamping element being adapted to be screwed onto the threaded rod, and bearing on the second bar outside the orifice, to bring the second bar closer to the first bar and thus clamp at least two reinforcements, the tube being configured to receive a guardrail post.

Description

Title of the invention: Device for fixing to a reinforcement lattice to support a guardrail upright Context and prior art

[0001] The present invention relates generally to safety equipment in the implementation of reinforced concrete slabs. A reinforced concrete slab is a cast concrete slab of significant thickness generally having a lower reinforcement layer and an upper reinforcement layer.

[0002] When the workers install the upper reinforcement layer before pouring the concrete, it is increasingly important to make their maneuvers safe and consequently there is a need to install guardrails at the level of the upper reinforcement layer in order to prevent any possible falls when the workers are or are moving on the upper reinforcement layer.

[0003] It has already been proposed to weld bases onto the reinforcement itself, said bases being able to support guardrail uprights. However, this requires having welding equipment available at this location and, moreover, this can weaken the reinforcement.

[0004] Furthermore, there are clamp systems which are inserted into a horizontal concrete wall but this is not well suited to the case of reinforcement which forms a mesh network of round metal profiles.

[0005] The inventors sought to propose a solution more suited to the case of mesh reinforcement. Another objective is to be able to reuse the proposed device in order to reduce the cost and the ecological footprint of the temporary installation of guardrails. Statement of the invention

[0006] To this end, a device forming a base for an upright is therefore proposed, the device being configured to be fixed to a mesh of reinforcement bars, in particular to at least two reinforcement bars (51, 52, 53, 54), the device comprising:

[0007] - a first bar (1) extending along a first axis (XI) between a first end (11) and a second end (12),

[0008] - a threaded rod (4) fixed to the first bar in its middle and extending along an axis of threaded rod (Z) perpendicular to the first axis,

[0009] - a second bar (2) extending along a second axis (X2) between a first end (21) and a second end (22), the second bar having in its middle a passage or an orifice (24), to leave a passage for the threaded rod,

[0010] - a clamping element (3), for example a screw cross, comprising a tube (32) having an axis W intended to coincide with the threaded rod axis, a nut (31) fixed to a longitudinal end of the tube, coaxially with the tube, and arms (33, 34), extending perpendicular to the tube, the clamping element being adapted to be screwed onto the threaded rod, and bearing on the second bar outside the orifice, to bring the second bar closer to the first bar and thus clamp at least two reinforcements,

[0011] the tube being configured to receive, from the outside or in an interior housing, an upright, in particular a guardrail upright, in order to maintain the upright substantially along the Z axis.

[0012] Thanks to these provisions, it is possible to install a guardrail system that rests on a mesh of reinforcement bars. The installation is simple, easy and robust.

[0013] It is noted that it is not necessary to weld or even have special equipment to install the guardrail base. The clamping element can in fact be screwed in by hand, thanks to the aforementioned arms.

[0014] It should be noted that the term "clamping element" should be taken in the broad sense and covers screw-nut type systems, rack mechanisms, ratchet mechanisms, a clamp system, a knee lever system, etc.

[0015] In practice, the clamping element can be called a "post"; a guardrail upright is fixed to this post. Similarly, in practice, the first and second bars can be called first and second "jaws" or "bits".

[0016] Advantageously, the device can even be left in place and in which case it is covered by the poured concrete. However, as an alternative, after dismantling the guardrail system, the clamping element can be unscrewed and the entire device removed, for subsequent reuse.

[0017] In various embodiments of the invention, one and / or the other of the following arrangements may optionally be used, taken individually or in combination.

[0018] According to one aspect, there may be provided, in the vicinity of each end of the first bar and in the vicinity of each end of the second bar, hollow or projecting shapes, to increase the grip on the reinforcements. Advantageously, when the clamping element is tightened, by screwing or otherwise, the grip of the bars on the reinforcement is of very good quality. Thus, the resistance to the forces exerted on the upright is high and the robustness of the guardrail system is advantageous. The hollow or projecting shapes may be formed as teeth or spikes.

[0019] According to one aspect, the hollow or projecting shapes may be concave housings in the profile of an arc of a circle. Whereby, when the reinforcements are irons of generally round section, the concave arc-shaped housings closely fit at least a portion of the round frame. The bars are then held on the frames very rigidly.

[0020] According to one aspect, the bars can be formed from square tubes with a transverse dimension (i.e. side of the square) of between 30 mm and 35 mm. This makes it possible to combine lightness and robustness. In addition, such hollow square tubes are very inexpensive. It should be noted that tubes with a rectangular section can also be chosen.

[0021] According to one aspect, the length of the bars can be between 25 cm and 45 cm. The device can thus be fixed to a mesh of reinforcements having a center distance ("pitch" of reinforcement) ranging from 20 to 40 cm.

[0022] In one aspect, all components of the device may be made of steel. This is a cheap and very strong material, with an optimized performance / weight ratio.

[0023] The device with its 3 main components preferably weighs less than 5 kg. It is therefore easy to handle and transport.

[0024] According to one aspect, the threaded rod may have a diameter of at least 16 mm, and a length of between 25 cm and 40 cm. With such a large diameter, the tightening pressure can be high without risking damaging the thread of the screw thread.

[0025] According to one aspect, the tube of the clamping element has a length L32 of between 30 cm and 50 cm.

[0026] According to one aspect, the length L32 of the tube of the clamping element is between 90% and 150% of the length (L4) of the threaded rod.

[0027] The invention also relates to a safety assembly comprising:

[0028] - a mesh of reinforcement bars, comprising a first layer L1 of reinforcement bars aligned on a first direction noted U1 and a second layer (L2) of reinforcements aligned on a second noted U2, U2 being perpendicular to Ul,

[0029] - a base-forming device as described previously,

[0030] - the first bar being placed under two adjacent reinforcements (51,52) of the first bed,

[0031] - the second bar being placed above two adjacent reinforcements (53,54) of the second bed,

[0032] - the screwing element being screwed onto the threaded rod so that the first and second bars grip the reinforcements of the first and second reinforcement layers. Advantageously, the device can be installed across several levels of reinforcement. This provides a wide base which gives very good stability to the base-forming device.

[0033] According to one aspect, U2 is perpendicular to Ul and the second axis (X2) is perpendicular to the first axis (XI).

[0034] The invention also relates to a safety system with a guardrail comprising:

[0035] - a mesh of reinforcement bars,

[0036] - at least one first base-forming device as described previously, enclosing at least two frames

[0037] - at least one second base-forming device as described previously, enclosing at least two frames

[0038] - a first upright (61) inserted into the first base-forming device,

[0039] - a second upright (62) inserted into the second base-forming device,

[0040] - at least one first rail (81) of guardrail extending between the first and second amounts, and fixed to both amounts.

[0041] The guardrail system may comprise a second horizontal rail (82) at a different height from the first.

[0042] Other aspects, aims and advantages of the invention will appear on reading the following description of an embodiment of the invention, given by way of non-limiting example. The invention will also be better understood with reference to the attached drawings in which:

[0043] - [Fig.l] schematically illustrates the device forming a base for an upright, according to a first embodiment, in an unassembled configuration,

[0044] - [Fig.2] schematically illustrates the device of [Fig.l] in a configuration assembly,

[0045] - [Fig.3] illustrates in perspective a bar,

[0046] - [Fig.4] illustrates in top view the device of [Fig.l] in a configuration assembled on two layers of reinforcement bars,

[0047] - [Fig.5] illustrates in section a concrete slab once poured, with two layers of reinforcement,

[0048] - [Fig.6] illustrates in section the construction site of the raft of [Fig.5] in an inter-stage preparation mediator,

[0049] - [Fig.7] illustrates an alternative embodiment concerning the attachment surfaces of the bars.

[0050] In the various figures, the same references designate identical or similar elements. For reasons of clarity of the description, certain elements may not be shown to scale.

[0051] With reference to figures 5 to 6, a site for preparing a reinforced concrete slab is described ([Fig.5]) with a view to obtaining a reinforced concrete slab such as that shown in [Fig.6].

[0052] It may be a thick foundation for an installation such as an underground metro station, a stadium base, a building foundation slab, etc.

[0053] For example, the thickness H0 of this raft can range from 60 cm to 1 m20.

[0054] In the lower part of the raft to be formed, a lower layer of reinforcement is installed. This lower layer of reinforcement, denoted 5inf, is made up in the illustrated example of four layers of reinforcement superimposed on top of each other alternately in directions orthogonal to each other.

[0055] This lower sheet is placed on shims 91.

[0056] Here, the term "reinforcement bed" means a set of reinforcements oriented in the direction, parallel to each other, and spaced apart from each other, by a reinforcement pitch (see El [Fig.4]). In other words, a reinforcement bed forms the base layer which makes up a sheet having several beds.

[0057] After installing the lower sheet, spacers 92 also called “chairs” are installed which will be useful for installing the upper sheet of reinforcements marked 5sup.

[0058] The upper layer is also made up in the example illustrated of four superimposed layers of reinforcement. In practice, it is when the WK companions install the reinforcements of the upper layer of reinforcements that the need to install a guardrail system arises.

[0059] Indeed, the height which separates the top of the lower sheet from the top of the upper sheet, noted H1 in figures 5 and 6, can be greater than 50 cm, which makes the movement of companions above the upper sheet subject to the risk of falling.

[0060] To this end, a guardrail system is installed with uprights 61,62 (generically designated by the reference 6) and horizontal rails 81,82. The horizontal rails are parallel to each other and at different heights. They are fixed to the uprights 61,62, thus forming a conventional construction site guardrail.

[0061] To install the uprights necessary for the guardrail system, a base-forming device, the main object of the present invention, was used.

[0062] The base-forming device comprises a first bar 1 extending between a first end 11 and a second end 12.

[0063] The first bar 1 extends along a first axis XI. Note that instead of “bar” we could also use “jaw” or “bit”.

[0064] In the example illustrated, the bar 1 is a square hollow tube. In the applications referred to here, the length L0 of the bar 1 is between 25 cm and 45 cm. The device can thus be fixed to a mesh of reinforcements having a center distance (or pitch) of a dimension EX (see [Fig.2]) which ranges from 20 to 40 cm.

[0065] In one example, the side of the square of the bar, denoted E2, is between 25 mm and 45 mm. A tube of rectangular section could also be suitable. The material thickness of the tube forming the bar can be between 2 mm and 3 mm.

[0066] With the first bar 1, a threaded rod 4 is provided extending along a threaded rod axis Z perpendicular to the first axis XI.

[0067] In one example, the diameter D4 is 20 mm. More generally, the diameter D4 of the threaded rod is greater than 16 mm.

[0068] In one example, the length L4 of the threaded rod may be between 30 cm and 40 cm.

[0069] The threaded rod is fixed to the first bar in its middle, at the same distance from the ends 11, 12.

[0070] In the example illustrated, a hole 14 is provided passing through the bar 1 in its middle. The threaded rod is threaded into the hole 14 with a slight overhang on one side. A weld 15 is made on the side of the slight overhang.

[0071] The weld is located on a so-called lower face of the bar, the threaded rod protruding substantially from the side of the so-called upper face.

[0072] On the side of the so-called upper face, hooking shapes 7 are provided to come into contact with a reinforcing frame. In the example illustrated, these are concave shapes. These are, for example, circular arcs 70.

[0073] The device further comprises a second bar 2 extending along a second axis X2 between a first end 21 and a second end 22.

[0074] The second bar 2 has an orifice 24 in its middle, to leave a passage for the threaded rod 4. The second bar 2 is a hollow square tube. Preferably, the second bar 2 has the same length and the same section as the first bar.

[0075] As for the first bar, attachment shapes 7 are provided, in particular for example circular arcs 70.

[0076] It is noted that the attachment shapes 7 provided on the first bar and the attachment shapes provided on the second bar are opposite each other to tighten a frame 5152.

[0077] The device further comprises a clamping element 3. In the example illustrated, this clamping element is in the form of a screw cross. However, as already mentioned, any system for pinching and / or tightening, such as a clamp, ratchet or rack system, could be suitable.

[0078] The clamping element 3 comprises a tube 32 having an axis W intended to coincide with the threaded rod axis.

[0079] The clamping element 3 comprises a nut 31 fixed to a longitudinal end of the tube, coaxially with the tube. The nut 31 has an internal thread which corresponds by complementary shape to the external thread of the threaded rod.

[0080] The clamping element 3 comprises arms 33, 34. The arms are preferably perpendicular to the tube. Each arm has a length of about fifteen to twenty centimeters. A ball or a head may be provided at the end of the arm to minimize the possible impact with a WK companion's leg.

[0081] The length of the tube L32 is between 25 cm and 45 cm.

[0082] The diameter of the D32 tube is between 30 mm and 40 mm.

[0083] The tube comprises an interior space 36, for receiving, on the side opposite the nut, a upright rod. The upright rod is preferably received inside the tube, but it is not excluded to receive an upright on the outside of the tube 32.

[0084] By means of the nut, the clamping element 3 is adapted to be screwed onto the threaded rod, as illustrated in [Fig.2].

[0085] The clamping element 3 bears on the second bar 2 outside the orifice 24, to bring the second bar closer to the first bar and thus clamp at least two reinforcements.

[0086] Now regarding the reinforcement mesh, successive reinforcement beds denoted L1, L2, L3, L4 are formed. Thus the lower layer 5inf comprises four reinforcement beds. Similarly, the upper layer 5sup comprises four reinforcement beds.

[0087] The first bed L1 of reinforcements comprises reinforcements aligned in a first direction Ul.

[0088] The second bed L2 of reinforcements comprises reinforcements aligned on a second U2.

[0089] As illustrated in [Fig.4], the bars grip two layers of reinforcements L1, L2. The first bar bears on the reinforcements 51 and 52 of the first layer L1. The second bar 2 bears on the reinforcements 53 and 54 belonging to the second layer L2.

[0090] As illustrated in [Fig.5], the bars hold four layers of reinforcement in a vice. Note that in Figures 4 and 5, the second bar is perpendicular to the first bar in top view. This provides robustness in all horizontal directions if the upright is stressed in any direction.

[0091] In the configuration of [Fig.2], the first and second bars only enclose a single bed of reinforcement, and are parallel to each other in the position after screwing.

[0092] It is noted that all the parts presented in the device are made of standard steel.

[0093] It is also noted that the device is very practical to use and comprises only three parts, namely the first bar 1 with its threaded rod, the second bar 2, and the screwing cross 3.

[0094] The sum of the weight of these parts does not exceed 5 kg, so the device is easy to transport, handle and install.

[0095] Regarding the installation, to pass the first bar with its threaded rod through one or more reinforcement beds, it is placed diagonally and inclined if necessary.

[0096] Furthermore, as apparent in [Fig.7], according to an alternative embodiment, it is provided with hollow or protruding shapes 7 in the form of surface teeth. Thus, the first bar and the second bar can grip two reinforcement rods, having any diameter as shown in dotted lines and having a center distance El not known precisely or having a significant dispersion in the reinforcement mesh. A single device can thus be used for reinforcement sites with different characteristics. The surface teeth make it possible to increase the grip on the reinforcements 52 without the position and diameter of the reinforcements being perfectly defined, thus taking into account a certain tolerance of positioning and dimensions.

Claims

Claims

1. 1. Device forming a base for an upright (6), the device being configured to be fixed to a mesh of reinforcement bars (5), in particular to at least two reinforcement bars (51, 52, 53, 54), the device comprising: - a first bar (1) extending along a first axis (XI) between a first end (11) and a second end (12), - a threaded rod (4) fixed to the first bar in its middle and extending along a threaded rod axis (Z) perpendicular to the first axis, - a second bar (2) extending along a second axis (X2) between a first end (21) and a second end (22), the second bar comprising in its middle a passage or an orifice (24), to leave a passage for the threaded rod, - a clamping element (3), for example a screw cross, comprising a tube (32) having an axis W intended to coincide with the threaded rod axis, a nut (31) fixed to a longitudinal end of the tube, coaxially to the tube,and arms (33, 34), extending perpendicular to the tube, the clamping element being adapted to be screwed onto the threaded rod, and bearing on the second bar outside the orifice, to bring the second bar closer to the first bar and thus clamp at least two reinforcements, the tube being configured to receive, from the outside or in an interior housing, an upright, in particular a guardrail upright, in order to maintain the upright substantially along the Z axis.,

2. 2. Device according to claim 1, in which there are provided, in the vicinity of each end of the first bar and in the vicinity of each end of the second bar, hollow or projecting shapes (7), to increase the grip on the reinforcements.

3. 3. Device according to claim 2, in which the hollow or projecting shapes are concave housings (70) in the profile of an arc of a circle.

4. 4. Device according to one of claims 1 to 3, in which the bars are formed from square tubes with a transverse dimension of between 30 mm and 35 mm.

5. 5. Device according to one of claims 1 to 4, in which the length (LO) of the bars is between 25 cm and 45 cm.

6. 6. Device according to one of claims 1 to 5, in which all the components of the device are made of steel.

7. 7. Device according to one of claims 1 to 6, in which the threaded rod has a diameter of at least 16 mm, and a length (L4) of between 25 cm and 40 cm.

8. 8. Device according to one of claims 1 to 7, in which the tube of the clamping element has a length (L32) of between 30 cm and 50 cm.

9. 9. Device according to claims 7 and 8, wherein the length (L32) of the tube of the clamping element is between 90% and 150% of the length (L4) of the threaded rod.

10. 10. Safety assembly comprising: - a mesh of reinforcement bars, comprising a first bed (L1) of reinforcement bars aligned in a first direction U1 and a second bed (L2) of reinforcement bars aligned in a second direction U2, U2 being perpendicular to Ul, - a base-forming device according to one of claims 1 to 9, - the first bar being placed under two adjacent reinforcement bars (51, 52) of the first bed, - the second bar being placed above two adjacent reinforcement bars (53, 54) of the second bed, - the screwing element (3) being screwed onto the threaded rod so that the first and second bars grip the reinforcement bars of the first and second layers of reinforcement bars.

11. 11. Safety assembly according to claim 10, in which U2 is perpendicular to Ul and the second axis (X2) is perpendicular to the first axis (XI).

12. 12. A guardrail safety system comprising: - a mesh of reinforcement bars, - at least one first base-forming device according to one of claims 1 to 9, enclosing at least two reinforcement bars - at least one second base-forming device according to one of claims 1 to 9, enclosing at least two reinforcement bars - a first upright (61) inserted into the first base-forming device, - a second upright (62) inserted into the second base-forming device, - at least one guardrail rail (8) extending between the first and second uprights, and fixed to the two uprights.

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