Device for stopping the flow of a construction material and method for renewing an expansion joint or a stop joint between two slabs

Abstract

The invention relates to a device (1) for stopping the flow of a curable construction material, such as concrete or mortar, the device being characterised in that it takes the form of a formwork strip comprising a corrugated upper longitudinal edge (2) and a straight lower longitudinal edge (3).

Description

Description Title of the invention: Device for stopping the flow of a construction material and method for renovating an expansion joint or a stop joint between two slabs Technical field

[0001] The invention relates to the technical field of construction, and in particular that of the production of slabs in a cast material.

[0002] More specifically, the invention relates to a pour stop device, as well as a method for renovating an expansion joint or a stop joint between two slabs. Prior art

[0003] In the field of construction, and in particular that relating to ground covering with concrete slabs, it is well known to use expansion joints between the slabs, to divide the concrete during pouring. The expansion joint is adapted to create an air space necessary to absorb the variations in volume of a slab, for example due to shrinkage during the drying of the concrete.

[0004] Document WO2018 / 215699, in the name of the Applicant, describes such an expansion joint.

[0005] It is also known to divide slabs with contraction joints, usually saw cuts, which are intended to prevent the concrete from cracking under the effect of thermal expansion.

[0006] A contraction joint involves creating a weak point by sawing through the hardened concrete slab by 1 / 3 of its thickness to create a fracture initiation point. In the event of significant shrinkage / expansion, the slab will crack at the bottom of the groove.

[0007] Also known is document WO2015 / 173549 which describes a flow stop device which can be used both as an expansion joint or as a repair joint for damaged expansion joints or contraction joints.

[0008] The devices described above comprise two longitudinal corrugated elements, with sinusoidal profiles, joined to each other so as to engage crests of one element with troughs of the other element.

[0009] In practice, each sinusoidal element is intended to form an integral part with an upper and horizontal edge of a concrete slab, the longitudinal elements being intended to move away from each other by a distance corresponding to the theoretical shrinkage after drying of the concrete slabs, and each longitudinal element comprises an external sinusoidal profile intended to be in contact with a concrete slab, and an internal sinusoidal profile in contact with the internal sinusoidal profile of the other sinusoidal element.

[0010] In this way, given that the separation between two adjacent slabs is made with a sinusoidal profile, the wheel of a vehicle driving over the slabs does not tend to fall between the two longitudinal elements of the joint. Said wheel does not hit the longitudinal elements of the joint when passing over the joint, but is in practice supported by one or other of the longitudinal elements of the adjacent slabs.

[0011] The devices described above are satisfactory, but can still be improved since they remain complex and expensive to implement. Statement of the invention

[0012] One of the aims of the invention is therefore to provide a flow stop device which can be used, both in new construction and in renovation, to provide a rolling surface without impact and jolts to a vehicle, in a simple and economical manner.

[0013] To this end, and to solve the aforementioned problems, a device has been developed for stopping the pouring of a hardenable construction material such as concrete or mortar, remarkable in that it is in the form of a formwork strip, preferably having a thickness, for example constant, of between 0.5 cm and 10 cm, and comprising a wavy upper longitudinal edge, and a straight lower longitudinal edge.

[0014] In this way, the device according to the invention can be used both for the creation of an expansion joint, i.e. in lost formwork, and for the renovation of an expansion joint or a stop joint between two concrete slabs.

[0015] In practice, the strip is suitable for creating a separation between two slabs of material cast on either side. The fact that the device is in the form of a single strip makes it possible to connect the upper and lower longitudinal edges by a single solid wall, making it possible to separate the slabs well with a corrugated shape, i.e. with a sinusoidal profile of the upper edge allowing a vehicle to pass through the joint without jolts or impact, and the lower straight edge allowing the slabs to each rest on its side so that the stresses in the cast and hardened material near the joint are uniformly distributed over the entire thickness of the slab, which very significantly reduces the appearance of disorders, such as cracks or breaks.

[0016] Furthermore, according to another advantageous characteristic, the edges are connected to each other by a compressible side wall, for example from a few millimeters to a few centimeters, to absorb horizontal shrinkage / expansion movements of the cast and hardened material.

[0017] In order to have sufficient compressibility, the device is for example made of expanded PVC foam, polymer material, composite material, or any other suitable material. It is quite possible to envisage having a device made from a complex having a metal core, bordered by two layers of foam. Of course, the person skilled in the art will know how to adapt the nature of the material according to the paving used and the shrinkage constraints it must undergo.

[0018] Advantageously, the device according to the invention can be made from a bio-sourced material, with the environmental advantages that this entails.

[0019] The side wall of the device preferably has a continuous surface to avoid sharp corners and effectively distribute stresses within the thickness of the slab.

[0020] According to a particular embodiment, the side wall has a corrugation whose amplitude decreases from the upper edge to the lower edge to reach zero amplitude at the lower edge.

[0021] Preferably, the amplitude of the undulation of the side wall is constant from the upper edge over a height of approximately 5 cm towards the lower edge, then decreasing towards the lower edge.

[0022] Advantageously, the side wall comprises a rectangular longitudinal section, that is to say one whose amplitude is zero, from the lower edge and over a height towards the upper edge of between 0.5 cm and 3 cm, so as to form a rectilinear portion which can be inserted into a space provided between two slabs.

[0023] Preferably, the lower edge has a tapered cross-section extending a height of between 0.5 cm and 3 cm from the lower edge to provide a wedging effect when inserted into the space between the tiles.

[0024] To promote this wedging effect, the side wall includes parallel longitudinal grooves arranged over a height of between 0.5 cm and 3 cm from the lower edge.

[0025] The device according to the invention can have any suitable length, for example between 1 m and 3 m. It can of course be cut to be shorter, or be attached to other identical devices to increase its length.

[0026] For this purpose, it advantageously includes complementary assembly means on vertical sections of the strip for assembling several devices together.

[0027] The invention also relates to a method for renovating an expansion joint or a stop joint between two concrete slabs, using the aforementioned formwork device.

[0028] According to the invention, the method is remarkable in that it comprises steps consisting of: - excavate a parallelepiped volume to replace the joint between the slabs, possibly over the entire thickness of the slabs; - optionally redo a saw cut at the bottom of the volume and along the volume; - position a device as mentioned above with the straight lower edge of the device placed at the bottom of the volume, preferably inserted in a space delimited between the two slabs; - pour a hardenable filling material, such as mortar, into the volume on either side of the device; - possibly level the upper edge of the device.

[0029] In this way, the renovation is simple, clean and fast. The device according to the invention forms a lost formwork, the hardened filling material leaves a space forming a joint with wavy edges allowing the circulation of a vehicle without impact, which space is filled by the device. Brief description of the drawings

[0030] [Fig. 1] illustrates a pour stop device according to the invention, seen in perspective.

[0031] [Fig. 2] is a top view of the device according to the invention.

[0032] [Fig. 3] is a view similar to that of Fig. 1, illustrating a longitudinal section at the upper edge of the device.

[0033] [Fig. 4] is a view similar to that of Fig. 3, illustrating a longitudinal section at a lower portion of the device, with a reduced amplitude ripple.

[0034] [Fig. 5] is a view similar to that of Fig. 3, illustrating a longitudinal section at the level of the straight lower edge of the device.

[0035] [Fig. 6] is a view similar to that of Fig. 1, illustrating a cross-section of the device at half the amplitude of the corrugated shape of the sidewall.

[0036] [Fig. 7] is a view similar to that of Fig. 6, illustrating a cross-section at the apex of the amplitude of the wavy shape.

[0037] [Fig. 8] illustrates the lower portion of the device, conical and fluted in shape. Detailed description of the invention

[0038] With reference to Figures 1 to 8, the invention relates to a pouring stop device (1), to be used as a formwork board in the production of slabs made of hardenable construction materials, such as concrete, tar, mortar, etc.

[0039] The device (1) is in particular in the form of a formwork strip, that is to say a flat element extending longitudinally, of the strip, rule, etc. type, capable of producing a vertical stop when pouring the material, and therefore a vertical separation (joint) between two slabs of material poured on either side. The invention therefore uses only one vertical separation element.

[0040] The device (1) thus comprises an upper longitudinal edge (2) which is wavy, in particular in the length direction with a so-called sinusoidal profile, and a rectilinear lower edge (3).

[0041] The sinusoidal undulating profile is of any type and can have radii of curvature or sharp angles of the sawtooth type, without departing from the scope of the invention. The sinusoidal profile extends on either side and symmetrically of a vertical plane passing through the straight edge. The undulating and sinusoidal profile is well known in the state of the art so that the person skilled in the art will know how to adapt the amplitude of the undulation of the upper edge according to the dimensional characteristics of its paving and the size of the wheels of the vehicles intended to circulate on it.

[0042] The upper longitudinal edge (2) and the lower longitudinal edge (3) are connected to each other by a side wall (4), preferably made of a compressible material of a few millimeters to a few centimeters depending on the nature of the cast material and the shrinkage / expansion constraints that the material must undergo. For example, the compressibility of the side wall (4) can be between 0.5 mm and 2 cm. The person skilled in the art will of course know how to adapt the material of the device (1) according to the slab that he wishes to create, noting that generally the shrinkage value of the different cements is between 450 and 750 micrometers per meter. In practice, it is observed that horizontal dimensional variations of the slabs are between 0.5 mm and 2 cm during shrinkage, from a few millimeters to 4 cm for thermal expansion and up to 8 during seismic stresses.

[0043] Depending on the variations in the size of the slabs, the person skilled in the art may, for example, produce the device (1) from expanded foam, from materials polymers, composite materials, or any suitable material. Of course, the material must be sufficiently rigid to hold the cast material. The skilled person will also know how to adapt it according to the load to be retained.

[0044] The device (1) has, for example, a thickness of between 0.5 cm and 2 cm, and a height of, for example, between 10 cm and 20 cm, of course to be adapted according to the thickness of the paving concerned, and the shrinkage / expansion constraints to be absorbed.

[0045] The advantage of the device (1) according to the invention is that it makes it possible to create a joint between two materials cast and hardened on either side, by defining a sinusoidal shape at the surface, i.e. which allows a vehicle to circulate without impacting the paving, and a rectilinear separation in the lower part, so as to distribute the stresses evenly within the paving and avoid subsequent problems, such as the appearance of cracks.

[0046] The transition from the wavy shape of the side wall (4), which starts from the upper edge (2), to the straight shape of the lower edge (3) is preferably made without sharp angles, for example by gradually decreasing the value of the amplitude of the wavy shape to reach a zero amplitude at the straight edge. In cross-section, the progressive decrease in the amplitude of the wavy shape defines an angle with respect to the vertical of less than 60°, preferably less than 45°.

[0047] According to the form of the illustrated embodiment, the side wall (4) has a corrugation whose amplitude is: - constant from the upper edge (2) and over a height of a few centimeters towards the lower edge (3), for example between 2 and 5 cm, see figures 3 and 7, - then gradually decreasing to a distance of between 0.5 and 3 cm from the lower edge (3), see figures 4 and 7, - then zero from this distance to the lower edge (3) so as to define a rectilinear lower portion which can be inserted into a space provided between the two slabs, see figures 5 and 7.

[0048] Advantageously, and with reference to Figure 8, the lower portion has a conical cross-section (5) extending over a height of between 0.5 and 3 cm from the lower edge (3) so as to be able to achieve a jamming when said lower edge (3) is inserted into the space provided between the slabs.

[0049] In order to promote the retention of the lower edge (3) in this space, the side wall (4) comprises grooves (6) or flutes, arranged longitudinally and parallel along the side wall (4), the grooves (6) being distributed over a height of between 0.5 cm and 3 cm from the lower edge (3).

[0050] The device (1) according to the invention has any suitable length, for example in the order of 1 m to 3 m. The device (1) is of course capable of being cut or extended as required. For example, several devices (1) can be assembled together to increase the total length.

[0051] For this purpose, and with reference to figures 1 and 3, complementary assembly means (7) are arranged on the vertical edges of the strip to be able to assemble several devices (1) together. For example, these means can be complementary male / female means, such as tenons / mortises, or else projecting nipples adapted to engage in complementary orifices.

[0052] The device (1) according to the invention is therefore well suited to producing formwork and a joint between two slabs, both in new construction and in a process of renovating an existing expansion joint, or a stop joint (saw cut) between two concrete slabs.

[0053] Under these conditions, the invention also discloses a method comprising steps consisting, firstly, in excavating a parallelepiped volume to replace the existing damaged joint, possibly over the entire thickness of the slab, and in removing the expansion joint if it is present.

[0054] The excavated volume generally leaves a delimited space between the two existing slabs at its base, corresponding to the shrinkage of the slabs after drying, or to the saw cut of the stop joint.

[0055] In the event that this space does not exist, it is possible to place the pouring stop device (1) according to the invention directly at the bottom of the volume, resting on the lower edge (3), but it is preferably recommended to make a saw cut at the bottom and along the volume.

[0056] The method then consists of placing the pouring stop device (1) either at the bottom of the volume, or preferably with the lower edge (3) inserted in the space delimited between the two slabs, then pouring a hardenable filling material, such as mortar for example, into the volume and on either side of the device (1).

[0057] If the upper edge (2) of the device (1) protrudes from the upper surface of the paving and the filling material, it is then possible to level said upper edge (2) to obtain a completely flat and renovated surface. Of course, the person skilled in the art will be able to add any surface preparation step, such as sanding or varnishing if necessary.

[0058] In this way, the invention provides a pour stop device (1) which can be used both in new construction and in renovation, for an impact-free and jolt-free rolling surface, which is of simple and economical design.

Claims

Claims 1. Device (1) for stopping the pouring of a hardenable construction material, such as concrete or mortar, characterized in that it is in the form of a formwork strip comprising a corrugated upper longitudinal edge (2) and a straight lower longitudinal edge (3).

2. Device (1) according to the preceding claim, characterized in that the upper longitudinal edge (2) and the lower longitudinal edge (3) are connected to each other by a side wall (4) made of a compressible material to absorb horizontal shrinkage / expansion movements of the cast and hardened material.

3. Device (1) according to claim 2, characterized in that it is made of expanded foam, polymer material, composite material, or bio-sourced material.

4. Device (1) according to one of the preceding claims, characterized in that the side wall (4) has a continuous surface.

5. Device (1) according to one of the preceding claims, characterized in that the side wall (4) has a corrugation whose amplitude decreases from the upper edge to the lower edge (3) to reach zero amplitude at the lower edge (3).

6. Device (1) according to claim 5, characterized in that the amplitude of the undulation of the side wall (4) is constant from the upper edge over a height of approximately 5 cm towards the lower edge (3), then decreasing to the lower edge (3).

7. Device (1) according to one of the preceding claims, characterized in that the side wall (4) comprises a rectangular longitudinal section, from the lower edge (3) and over a height towards the upper edge of between 0.5 cm and 3 cm, so as to form a rectilinear portion which can be inserted into a space provided between two slabs.

8. Device (1) according to claim 7, characterized in that the lower edge (3) has a conical cross-section (5) extending over a height of between 0.5 cm and 3 cm from the lower edge (3). he 9. Device (1) according to one of claims 7 to 8, characterized in that the side wall (4) comprises parallel longitudinal grooves (6) arranged over a height of between 0.5 cm and 3 cm from the lower edge (3).

10. Device (1) according to one of the preceding claims, characterized in that it comprises complementary assembly means (7) on vertical edges of the strip for assembling several devices (1) together.

11. Method for renovating an expansion joint or a stop joint between two concrete slabs, the method comprising steps consisting of: - excavate a parallelepiped volume to replace the joint between the slabs; possibly over the entire thickness of the slabs; - optionally redo a saw cut at the bottom of the volume and along the volume; - positioning a device (1) according to one of the preceding claims with the rectilinear lower edge (3) of the device (1) placed at the bottom of the volume, preferably inserted in a space delimited between the two concrete slabs; - pouring into the volume a hardenable filling material, such as mortar, on either side of the device (1); - possibly level the upper edge of the device (1).

Images