METHOD FOR CAULKING AND SEALING JOINTS BETWEEN REMOVABLE SLABS AND REMOVABLE SLABS WITH SEALED JOINTS BY MEANS OF SAID METHOD

Abstract

A method for sealing joints in removable slabs (1a, 1b) separated by gaps (E) without fibrous elements, comprising, for at least one of said gaps: a. the creation of a joint backing by positioning at the bottom of said gap one or more elastic elements (2) made of preformed polymer foam with a cross-section adapted to fill the width of said gap (E), b. filling an upper portion of said gap (E), above the joint backing, with a layer of two-component silicone elastomer (3) curable by polyaddition, c. curing said two-component silicone layer (3) to create a removable sealing coating for said gap. Figure 3

Description

Title of the invention: METHOD FOR SEALING AND PROOFING JOINTS BETWEEN REMOVABLE SLABS AND REMOVABLE SLABS WITH SEALED JOINTS BY MEANS OF SAID METHOD Technical field

[0001] The invention relates to the field of caulking and sealing of joints between removable slabs, particularly applicable to removable reinforced concrete slabs for industrial sites and especially nuclear power plants. Previous technique

[0002] Sensitive industrial sites, and in particular nuclear power plants, may contain removable reinforced concrete handling slabs. These are regularly removed and reinstalled during outages, requiring rapid implementation and readily available teams. Added to this are the constraints of protection against risks, primarily fire and flooding. It is therefore necessary to offer fast-setting products to ensure a return to normal as quickly as possible in terms of fire compartmentation.

[0003] When treating floors equipped with handling slabs with regard to fire risk, it is necessary to join the slabs together and secure them to the concrete floor using a joint backing system in the form of a mineral braid, for example, rock wool, and a silicone sealant adhesive that meets the fire-resistant and water-tightness requirements. This conventional system requires surface preparation, application of the joint backing, and the extrusion of sealant cartridges, resulting in lengthy installation times. Furthermore, this system also makes future maintenance operations cumbersome: cutting the sealant and joint backing with a utility knife, sanding the surfaces to remove all traces of residue, and systematically disposing of products that cannot be reused.Document WO2009 / 133261 Al deals in particular with a firestopping and sealing device comprising a pre-formed elastic foam element of variable cross-section and length which is applied between the slabs inside the joint to be treated. This device provides firestopping but does not ensure true watertightness. Technical problem

[0004] In order to overcome these difficulties, the present disclosure describes a fire-resistant and water-sealing solution adapted to removable slabs, allowing for easy installation and removal, as well as partial or total reuse of the products composing it. Description of the invention

[0005] In view of this situation, the present disclosure proposes a fibrous-free sealing method for joints in removable slabs separated by gaps, which comprises, for at least one of said gaps: a. the creation of a joint backing by positioning at the bottom of said space one or more elastic elements made of pre-formed polymer foam with a cross-section adapted to fill the width of said space, b. filling the upper part of said space, above the joint base, with a layer of two-component silicone elastomer crosslinkable by polyaddition, c. crosslinking said two-component silicone layer to create a removable caulking coating for said space.

[0006] The two-component, room-curable, polyaddition silicone elastomer combines in particular: a. good fire-resistant properties, b. an extremely low glass transition temperature for a polymer, allowing it to retain its elastic properties over a wide temperature range. c. excellent mechanical strength resulting in high stress and elongation at break, d. a low shrinkage of less than 0.1% during crosslinking, e. the possibility of modulating its catalysis in order to adapt its setting time to business constraints. f. and unlike one-component silicone sealant, a low surface tension allowing modest cohesion to a substrate.

[0007] The features described in the following paragraphs correspond to embodiments that can be implemented independently of each other or in combination with each other:

[0008] said elastic elements of the joint base and said layer of two-component silicone elastomer can in particular come as a replacement for a mineral wool joint base glued between the slabs and covered by a single-component sealant of silicone, polyurethane or hybrid type.

[0009] The preformed polymer foam can be polyurethane, silicone, EPDM or polyethylene foam.

[0010] The preformed polymer foam may be a polyurethane foam with fire-resistant fillers.

[0011] The preformed polymer foam can also be a polyurethane foam with intumescent fillers.

[0012] The elastic elements in preformed foam are advantageously inserted into the spaces with a compression ratio of 10 to 60% and preferably of 25% to 35%.

[0013] The two-component silicone elastomer preferably comprises at least a base having a first component mixture of vinyl-terminated silicone oils (Si-Vi), a second crosslinking component having hydrosiloxane motifs (Si-H) and an organometallic catalyst, said silicone being crosslinkable by hydrosilylation.

[0014] The silicone elastomer, which is distributed in cartridges connected to a known type mixing device for depositing the coating, is crosslinkable by hydrosilylation.

[0015] According to a preferred embodiment, the removable caulking coating is deposited with a thickness of at least 5 mm.

[0016] The two-component silicone elastomer layer is advantageously deposited on a thickness providing water tightness to said removable caulking coating of at least 20 cm of water column for a period of 24 hours.

[0017] The viscosity of the two-component silicone is adaptable so as to produce a flowing silicone for application on a horizontal surface or a non-flowing silicone for application on a vertical surface.

[0018] The spaces preferably form trenches with a width of 10 mm to 80 mm and a height corresponding to the thickness of the slabs, for example 150 mm to 200 mm.

[0019] The invention provides a method for dismantling caulked slabs according to the method of the invention, comprising for at least one caulked space (Ec) a first step of tearing off (A) the cross-linked silicone elastomer coating, a second step of removing (R) the pre-formed foam elastic element(s) from the joint base, a recovery of said elastic elements and a disposal of said coating.

[0020] The removal of the elastomeric coating which will be destroyed and the removal of the recoverable elastic element have the advantage of being able to be done by hand without requiring tools.

[0021] The invention further proposes a fire-resistant and water-sealing joint sealing system comprising a flexible and elastic profile coated with a silicone elastomer crosslinked by a polyaddition chemistry. This system is designed to eliminate the need for fibrous materials such as mineral fibers. artificial siliceous vitreous including refractory ceramic fibers (silicate fibers containing alkali oxides and alkaline-earth oxides), glass fibers, glass wool, rock wool, slag wool and continuous glass filaments.

[0022] The constituent elements are advantageously not glued, and removable without tools.

[0023] The flexible and elastic profile is advantageously a polymer foam.

[0024] The flexible and elastic profile can be at least partially covered with a film polyethylene.

[0025] Said polymer is preferably chosen from polyurethane, silicone, EPDM or polyethylene.

[0026] Said polymer foam may in particular be an intumescent polyurethane foam which increases the fire resistance of the joint beyond the fire resistance provided by the silicone elastomer.

[0027] Said polymer foam is advantageously a preformed foam with a fire resistance greater than or equal to two hours, resistance E1120 according to standard EN1366-4.

[0028] The flexible and elastic profile is advantageously cylindrical or ovoid in shape, which facilitates its insertion into the space to be sealed and its removal from this space.

[0029] The silicone elastomer is in particular a cold-curing two-component silicone (EVF or RTV) by a polyaddition chemistry resulting from a hydrosilylation reaction between vinyl-terminated silicone oils (Si-Vi) and silicone oils possessing hydrosiloxane motifs (Si-H).

[0030] The invention and variants thereof can generally make it possible to provide a floor or wall that is watertight and / or fire-resistant when the slabs are reinforced concrete slabs.

[0031] Such a solution makes it possible to guarantee both the sealing and fire protection as well as the dismantling of temporary protective slabs for the passage of handling equipment in particular used in industrial or nuclear installations. Brief description of the drawings

[0032] Other features, details and advantages of the invention will become apparent from the following detailed description of non-limiting embodiments and from the analysis of the accompanying drawings, in which:

[0033] [Fig. 1] shows a schematic view of spaced slabs to create a floor or a ceiling;

[0034] [Fig.2] shows a schematic view of the slabs of [Fig.1] with a joint backing made with a pre-formed elastic foam element;

[0035] [Fig.3] shows a schematic view of the slabs of [Fig.2] with removable caulking coating on the bottom of the joint;

[0036] [Fig.4] shows a tearing of the caulking coating;

[0037] [Fig.5] shows a retraction of the joint base. Description of the implementation methods

[0038] The drawings and description below contain elements that can not only serve to better understand the present invention, but also contribute to its definition, if necessary.

[0039] Fig. 1 schematically represents removable slabs 1a, 1b separated by a space E. It should be noted that in the figures illustrating the invention the dimensions of the slabs are not representative of reality.

[0040] The slabs are preferably reinforced concrete slabs. The slabs can, for example, be fixed by bolts to crossbeams not shown or to metal angle brackets C in a known manner.

[0041] To achieve the sealing of slab joints, the invention provides a fire-resistant and water-sealing joint sealing system using a flexible and elastic profile covered with a silicone elastomer and a sealing process which, according to [Fig.2], will include the creation of a joint base by positioning at the bottom of said space one or more elastic elements 2 made of pre-formed foam with a cross-section adapted to fill the width of said space E.

[0042] These elastic elements will fill the bottom of space E, thereby creating a first watertight barrier due to their compression across the width of the space. For this purpose, pre-formed foam elastic elements are chosen with a width such that they are inserted into the spaces with a compression ratio of 10 to 60%, but preferably limited to a compression ratio of 25% to 35%.

[0043] Generally, the spaces E form trenches with a width of 10 mm to 30 mm and their height corresponds to the thickness of the slabs, for example, 150 mm to 200 mm. In qualification or other configurations, the trench widths can be up to 80 mm.

[0044] The elastic elements are flexible and elastic profiles preferably of cylindrical or ovoid shape to allow their easy insertion into the spaces between slabs.

[0045] They are made of a foam of a polymer which can be chosen from polyurethane, silicone, EPDM or PE. In the case of polyurethane, which is preferred, an intumescent polyurethane foam will be chosen to produce a preformed foam preferably having a fire resistance of at least two hours (El 120) according to the test standard EN1366-4.

[0046] An example of usable polyurethane foam is a foam marketed by the applicant under the trade name NuMINE_108.

[0047] In addition, in the case where fire-resistant compartmentation is desirable, the preformed foam is an intumescent polyurethane foam.

[0048] Once the elastic elements are correctly positioned, the upper part of the space above the joint base will be filled with a layer of two-component silicone elastomer 3 crosslinkable by polyaddition and wait for said two-component silicone layer 3 to set before applying a sealant coating to said space as shown schematically in [Fig.3] for which the height of the slabs is reduced compared to reality in which the height of the slabs of 150 mm to 200 mm greatly exceeds the height of the joint by the order of .

[0049] Said two-component silicone elastomer layer 3 is deposited to a thickness providing a watertight seal to said removable caulking coating. The removable caulking coating can be deposited to a thickness of at least 5 mm; a test with a thickness of 10 mm applied in a 20 mm joint opening resulted in a system that was watertight against a 20 cm water column for 24 hours.

[0050] To avoid the accumulation of deposits or stagnant water, the joint is laid so as to have a top surface flush with the top surface of the slabs.

[0051] The silicone elastomer is a two-component cold-curing silicone (EVF or RTV) by a polyaddition chemistry resulting from a hydrosilylation reaction between vinyl-terminated silicone oils (Si-Vi) and silicone oils possessing hydrosiloxane motifs (Si-H).

[0052] These elastomers are conventionally packaged as two-component compositions to be mixed during processing. The first component incorporates polyorganosiloxane oils with vinyl functional groups and a hydrosylation catalyst. Preferably, this catalyst is a platinum organometallic complex (such as the Karstedt catalyst). The second component comprises polyorganosiloxane oils with at least three Si-H type motifs per molecule, thus enabling crosslinking of the material. This part generally also incorporates a setting retarder such as tetramethyltetravinylcyclotetrasiloxane (ViD4), which modulates the catalytic activity of the platinum complex. Finally, other constituents are added to both parts, such as reinforcing fillers (fumed silica, etc.) and diluting fillers (calcium carbonate, etc.).), colorants, plasticizers such as non-reactive polyorganosiloxane oils, .... .

[0053] Such compositions are marketed by the applicant in particular under the trade name NuMINE_E18.

[0054] This two-component silicone, which is air-curable by polyaddition chemistry, has the advantage of combining:

[0055] good fire resistance properties,

[0056] an extremely low glass transition temperature for a polymer enabling it to retain its elastic properties over a wide temperature range,

[0057] excellent mechanical strength resulting in high stress and elongation at break,

[0058] a low surface tension allowing modest cohesion to a substrate,

[0059] a low shrinkage of less than 0.1% during crosslinking,

[0060] the possibility of modulating its rheology (flowing or non-flowing depending on whether it is to be applied horizontally or vertically),

[0061] the possibility of modulating its catalysis in order to adapt its setting time to business constraints.

[0062] The silicone filling the space to a thickness of about ten mm thus makes it possible to quickly provide the system with water sealing functions but also with surface decontamination of the joint on which irradiated contaminants do not stick.

[0063] Thus according to the invention, said elastic element(s) 2 of the joint base and said two-component silicone layer 3 come as a replacement for a single-component silicone adhesive sealant glued between the slabs and / or for a packing of glue and rock wool.

[0064] To enable the creation of joints in vertical walls or floors, the viscosity of the two-component silicone is adaptable so as to produce a flowing silicone for application on a horizontal surface or a non-flowing silicone for application on a vertical surface.

[0065] The advantage of the silicone used is that it is non-stick and therefore easy to remove, making the sealant removable and allowing for quick dismantling of the sealed spaces Ec between the slabs. According to [Fig. 4], dismantling begins with a first step A of peeling off the cross-linked silicone sealant. This sealant is removed practically in one piece without tearing, thus avoiding the possibility of ending up with potentially contaminated pieces of varying sizes. Next, a second step R is carried out, removing the pre-formed foam elastic element(s) from the joint base according to [Fig. 5], followed by the recovery of said elastic elements. The cross-linked silicone sealant can then be discarded.

[0066] The process described in this disclosure proposes the implementation of a joint sealing system, particularly for slabs with a thickness of 150 mm to 200 mm, combining: - ease of implementation without the need for surface preparation, - a reduced setting time of less than 30 minutes, resulting in rapid commissioning of the traffic flow above the slab, - Good fire resistance, for example, a fire resistance of at least two hours (El 120) according to the EN1366-4 test standard for a system comprising a fire-resistant intumescent PU foam elastic element, a 26 mm diameter profile for a 20 mm joint width and therefore a compression ratio of 30%, the addition of silicone extending the time - a water column seal of at least 20 cm for a silicone coating approximately 10 mm thick, - mechanical resistance to pedestrian traffic and also to the movement of heavy machinery, - an adaptation to the variability of joint widths encountered resulting from the positioning of the slabs and site constraints; a tolerance of plus or minus 20% is obtained in the case of a PU foam profile due to the intrinsic elasticity of this profile, - easy removal by simple manual pulling without the use of any specific tools, - Simplified repairability in the event of partial opening of the slabs, meaning that if part of the sealant is damaged, it is not necessary to replace the entire sealant. It is sufficient to simply replace the damaged piece of PU foam and re-pour the two-component elastomer over it. - partial reuse of the system without generating waste other than the silicone coating, - Installation and reinstallation that is as easy as possible and can be carried out by non-specialists subject to simple training, Industrial application

[0067] The invention may be applicable in particular to the protection of surfaces of industrial or nuclear buildings.

[0068] The invention is not limited to the examples described above, only by way of example, but encompasses all the variants that a person skilled in the art may consider within the framework of the annexed claims.

Claims

Demands

1. A method for sealing joints of removable slabs (a, 1b) separated by spaces (E) without fibrous elements, characterized in that it comprises, for at least one of said spaces: a. the creation of a joint backer rod by positioning at the bottom of said space one or more elastic elements (2) of preformed polymer foam of cross-section adapted to fill the width of said space (E), b. a filling of an upper part of said space (E), above the joint backer rod with a layer of two-component silicone elastomer (3) cross-linkable by polyaddition, c. the cross-linking of said two-component silicone layer (3) to create a removable sealing coating for said space.

2. Method according to claim 1, wherein said elastic element(s) (2) of the joint backer and said two-component silicone elastomer layer (3) replace a mineral wool joint backer bonded between the slabs and covered by a one-component sealant of silicone, polyurethane or hybrid type.

3. A method according to any one of the preceding claims, wherein the preformed polymer foam is a polyurethane, silicone, EPDM or polyethylene foam.

4. A method according to claim 3 wherein the preformed polymer foam is a polyurethane foam with fire-resistant fillers.

5. A method according to claim 3 wherein the preformed polymer foam is a polyurethane foam with intumescent fillers.

6. A method according to any one of the preceding claims, wherein the elastic elements (2) made of preformed foam are inserted into the spaces with a compression ratio of 10 to 60% and preferably of 25% to 35%.

7. A method according to any one of the preceding claims, wherein the two-component silicone elastomer comprises a base having a first component, a mixture of vinyl-terminated silicone oils (Si-Vi), and a second crosslinking component possessing hydrosiloxane (Si-H) motifs and an organometallic catalyst, said silicone being crosslinkable by hydrosilylation.

8. A method according to any one of the preceding claims, wherein the removable caulking coating is deposited to a thickness of at least 5 mm.

9. A method according to any one of the preceding claims, wherein said two-component silicone elastomer layer (3) is deposited on a thickness providing water tightness to said removable caulking coating of at least 20 cm of water column for a period of 24 hours.

10. A method according to any one of the preceding claims, wherein the viscosity of the two-component silicone is adaptable so as to produce a flowing silicone for application on a horizontal surface or a non-flowing silicone for application on a vertical surface.

11. A method according to any one of the preceding claims, wherein the spaces (E) form trenches with a width of 10 mm to 80 mm and a height corresponding to the thickness of the slabs.

12. Method of dismantling caulked slabs according to the method of any one of the preceding claims, comprising for at least one caulked space (Ec) a first step of tearing off (A) the cross-linked silicone elastomer coating, a second step of removing (R) the pre-formed foam elastic element(s) from the joint base, recovery of said elastic elements and disposal of said coating.

13. Firestop and watertight joint sealing system characterized in that it comprises a flexible and elastic profile covered with a silicone elastomer crosslinkable by a polyaddition chemistry and is free of fibrous materials.

14. Firestop joint sealing system according to claim 13 wherein the constituent elements are not glued.

15. Firestop joint sealing system according to claim 13 or 14 wherein the flexible and elastic profile is a polymer foam.

16. Firestop joint sealing system according to claim 15 wherein the flexible and elastic profile is at least partially covered with a polyethylene film.

17. Firestop joint sealing system according to claim 15 wherein said polymer is selected from polyurethane, silicone, EPDM or polyethylene.

18. Firestop joint sealing system according to claim 15 wherein said polymer foam is an intumescent polyurethane foam.

19. Firestop joint sealing system according to claim 15 wherein said polymer foam is a preformed foam of a fire resistance greater than or equal to two hours, resistance E1120 according to standard EN1366-4.

20. Firestop joint sealing system according to any one of claims 13 to 19 wherein the flexible and elastic profile is cylindrical or ovoid in shape.

21. Firestop joint sealing system according to any one of claims 13 to 20, wherein the silicone elastomer is a cold-curing two-component silicone (EVF or RTV) by a polyaddition chemistry resulting from a hydrosilylation reaction between vinyl-terminated silicone oils (Si-Vi) and silicone oils having hydrosiloxane motifs (Si-H).

Images