DEVICE AND METHOD FOR PRODUCING COMPONENTS FROM CONCRETE AND CONCRETE COMPONENTS PRODUCED BY MEANS THEREOF

Abstract

The invention relates to a formwork element for a formwork system for concrete building purposes, in particular for integration into a construction plane of the formwork system, having a box-like supporting body (1, 2) facing away from the concrete, having an upper side (6) facing the concrete in use, having a recess (3) in the upper side (6) for the fastening of concrete-facing forming means (11; 11′; 35) which can be fastened on/in the recess (3), having a vacuum-permeable spacer (14; 17) having a plurality of passage openings (16), and having connection devices (7, 8, 9) for applying a vacuum, wherein a plurality of forming means (35) can be reversibly fastened by means of vacuum at the top side (6). The invention also relates to a formwork system having such a formwork element and a concrete component which has been created with the formwork element or the formwork system.

Claims

1. Formwork element (32) for a formwork system for concrete building purposes, in particular for integration into a construction plane of the formwork system, having a box-like concrete supporting body (1, 2) facing away from the concrete, having an upper side (6) facing towards the concrete in use, with a recess (3) in the upper side (6) for fastening concrete-facing forming means (11; 11′; 35) which can be attached to/in the recess (3), having a vacuum-permeable spacer (14; 17) having a plurality of passage openings (16) and having connection devices (7, 8, 9) for applying a vacuum, so that a plurality of forming means (35) can be reversibly fastened on the upper side (6) by means of vacuum.

2. Formwork element according to the preceding claim, characterized by passage openings (16) which can be closed by the forming means (35) suctioned under vacuum.

3. Formwork element according to the preceding claim, characterized by a plurality of lost forming means (35) which are configured to adhere to the spacer by vacuum and to remain in the concrete.

4. Formwork element according to one of the preceding claims, characterized by a partially perforated intermediate layer (22) for mounting on the spacer or a die (11).

5. Formwork element according to one of the preceding claims, characterized by a die (11′) having a structure which determines the concrete surface of the future concrete component as a forming means.

6. Formwork element according to one of the preceding claims, characterized by a perforated die (11′) which spans the recess and can be closed by lost forming means (35).

7. Formwork element according to the preceding claim, characterized by a one-piece configuration of the die and of the spacer.

8. Formwork element according to the preceding claim, characterized in that the die comprises a composite layer structure of a rigid stability layer, an elastic sealing layer and a contact layer.

9. Formwork element according to one of the preceding claims, having a three-dimensionally extending upper side.

10. Formwork system for concrete building purposes having a number of formwork elements for configuring a concrete formwork structure for receiving fresh concrete, with at least one formwork element according to one of the above claims.

11. Method for producing a concrete component having a formwork system according to claim 7, having the following steps: a) Creating a concrete formwork including at least one formwork element according to one of claims 1 to 6, b) Applying a vacuum to the formwork element, c) Positioning a forming means on the supporting body, d) Introducing fresh concrete, e) Setting the concrete, f) Stripping the concrete component.

12. Method according to the above method claim, wherein the vacuum is switched off when the green strength of the concrete is reached.

13. Use of vacuum in the creation of a concrete formwork structure for the positioning of a forming means on the concrete-contacting inner side of the formwork, the positioning being free of fastening means and exactly located.

14. Concrete component having a designed surface, which is produced by means of a formwork element according to one of claims 1 to 7 or by a method according to claim 8.

Description

[0042] The principle of the invention is explained in more detail below by means of a drawing, by way of example. The drawings show:

[0043] FIG. 1: A first formwork element according to the invention in a partial sectional view,

[0044] FIG. 2: Formwork element of FIG. 1 in a cut-away perspective view,

[0045] FIG. 3: A second formwork element according to the invention,

[0046] FIG. 4: A further formwork element according to the invention having a curved object holder,

[0047] FIG. 5: A selection of concrete components which can be produced according to the invention,

[0048] FIG. 6: A section through a system formwork.

[0049] FIGS. 1 and 2 show a formwork element 32 according to the invention for producing a concrete slab 30, one surface of which is provided with uniformly distributed glass beads 35 (only in FIG. 1). The formwork element 32 comprises a rectangular polymer base plate 1 as a component or rear wall of a supporting body of the formwork element 32. At the edge of the base plate 1 are affixed circumferential side edges 2, which together with the base plate 1 form a supporting body and enclose a largely cubic cavity 3. The side walls 2 have outwardly directed end faces 4 which run at right angles to the base plate 1. The side edges 2 each terminate with a surface 5, which are aligned parallel to the base plate 1. The surfaces 5 of the side walls 2 define an upper side 6 of the formwork element, which is divided by the cavity 3 as a recess of the formwork element and the upper sides 5 surrounding it. On the end faces 4, the formwork element has six connection devices or fluidic connections 7 which are each connected to a coaxial bore 8 in the plate plane of the base plate 1. Each bore 8 opens in a groove 9 running transversely to it. The groove 9 is milled from the direction of the upper side 6 into the base plate 1 and connects the adjacent bores 8 of the connections 7. With its open side, the groove 9 adjoins the cavity 3. There is thus a fluidic bond between the connection 7 and the cavity 3, which is used as a vacuum chamber after the application of negative pressure at the connections 7, via the connection 7, the bore 8 and the groove 9.

[0050] The side walls 2 run at the four edges of the rectangular base plate 1 and each composed of, in the direction orthogonal to the base plate 1, a strip-shaped and approximately 6 mm thick grating holder 10 made of PVC, a plate-shaped object support 11 supported thereon, and a strip-shaped clamping strip 12 approximately 21 mm thick. The object support 11, as a plate-shaped die, is a formwork shell of the formwork element 32 and is made of PVC with laminated EPDM. The clamping strips 12 are screwed into the base plate 1 by means of a plurality of M8×40 hexagonal screws. They clamp both the grating holder 10 and the object support 11 between them. While the grating holder 10 has largely the same width and length dimensions as the clamping strip 12, the object support 11 extends essentially over the same surface as the base plate 1. It thus projects into the cavity 3. Parallel to this, a spot welding grid 14 having a mesh width of 25×25 mm is fastened in the grating holder 10. It extends between the base plate 1 and the object support 11 over the entire surface of the base plate 1, is exposed in the region of the cavity 3, and supports the object support 11 on the lower side. It is thus used as a spacer between the object holder 11 on the one hand and the base plate 1 on the other hand, which maintains the cavity 3. It prevents a possible bulging of the object support 11 as a result of the vacuum which occurs later by the evacuation. Four round cords 15 with a diameter of 4 mm each seal in pairs the grating holder 10 opposite the object support 11 on the one hand and the base plate 1 on the other hand.

[0051] The additive construction of the formwork element enables, on the one hand, the modular joining of several individual elements to enlarge formwork elements, and on the other hand, to exchange individual components. The possibility of exchanging the object support 11 is of particular advantage. Depending on the application, it can be optimized with regard to the number of recesses, its cross-section or its material properties.

[0052] Depending on the design desire of the concrete slab 30 to be produced, the object support 11 is thus designed or provided with openings. In the present case, the object support 11 has, as a rigid piercing die, regularly arranged through holes 16 with a diameter of 6 mm, which lead into the cavity 3 as a spacer through the spot welding grid 14. The object support 11 is used to be coated with the glass beads 35, which are cast into the surface of the concrete slab 30.

[0053] Through the embedding of the glass beads 35 in the manner shown, each bead 35 also receives particular reflection properties. Incident radiation is reflected largely independently of the orientation of the bead 35 mostly in the direction back to the radiation source. This reflection behavior arises due to the embedding, i.e., without additional modifications of the bead 35. The reflection behavior of the beads 35 embedded in the concrete surface is the one retroreflector.

[0054] The production of the concrete slab 30 takes place by first coating the object support 11 with glass beads 35. As soon as the object support 11 is completely coated and each of its through holes 16 is closed by means of a glass bead 35, vacuum is applied to the connections 7. The EPDM lamination on the object support 11 ensures reliable sealing of the through holes 16 by the beads 35. The vacuum reduces or evacuates the pressure in the cavity 3, the groove 9 and the bore 8. As a result, the glass beads 35 are sucked on and held on the object support 11 in a captive manner or immovably. Now the formwork element 32 may even be erected and possibly integrated into a conventional system formwork. The vacuum is sufficiently strong that the glass beads 35 are also held in a vertical position of the formwork element 32, but they can resist a concrete thrust in any case during the introduction of the concrete.

[0055] The vacuum generation can be reduced and finally switched off while the concrete is setting. That is because with increasing hardening of the concrete, the glass beads 35 are held by it and no longer need any adhesion to the object support 11. After the concrete has set, the formwork can finally be removed and with it the formwork element 32. The glass beads 35 detach easily from the object support 11 at the same time. They are now permanently incorporated and fastened in the concrete slab 30.

[0056] The object support 11 according to FIG. 1, just like the glass beads 35, is a forming means for the concrete slab 30 to be produced. In addition, the glass beads 35 themselves form a type of lost formwork or lost forming means because they remain in the concrete slab 30 after completion of the concreting operation. Moreover, they also cause a functionalization of the concrete component because they together form a reflector on the concrete surface in the above manner. According to the same principle, opposing formwork elements for electrotechnical installations can also be positioned on the formwork element 32 according to the invention and installed in a concrete component:

[0057] FIG. 3 shows a section comparable to FIG. 1, wherein, in contrast, glass beads 35 are not applied to the object support 11, but rather an opposing formwork element 20. It covers a plurality of through holes 16 of the object support 11 and rests with a rubber seal 21 on the object support 11 so that it is reliably sucked through the through holes 16 of the object support 11 on it. The remaining through holes 16 which are not covered by the opposing formwork element 20, conceal a wooden support 22 so that all the through holes 16 of the object support 11 are closed. During the subsequent concreting process, which in principle takes place in the same way as already mentioned above, the formwork element 32 according to the invention holds the opposing formwork element 20 in the correct position during the concreting. After switching off the vacuum generation, the opposing formwork element 20 and the wooden support 22 can be easily released from the object support 11 of the formwork element 32 without using tools. This can then be re-used for a further concreting operation without any significant cleaning or other post-processing operations.

[0058] The formwork element according to the invention can also be used without the use of functional elements for the design of a surface of a concrete component. FIG. 5h shows a concrete component 30 with a curved surface 31, from which a passage 36 completely penetrates the concrete component 30. It can be produced with a formwork element according to FIG. 4, using a closed, flat and corrugated object holder, which carries an opposing formwork element 20 according to the principle shown in FIG. 3 for the configuration of the passage 36.

[0059] FIG. 4 shows a partial section through a further example of a formwork element according to the invention. In principle, similar to those of FIGS. 1 to 3, it is composed of a base plate 1 having a vacuum connection comprising the bores 8 and the groove 9. However, its side walls 2 protrude further and, by means of the clamping strip 12 and the hexagonal screw 13, clamp a three-dimensionally shaped die as an object support 11′, which has a plurality of through holes 16. In them, glass beads 35, which occupy the future surface of a concrete component 30 as functional particles, are predominantly on the concrete side.

[0060] A spacer 17 is inserted at those locations at which the object support 11′ approaches the base plate 1 and a risk therefore exists that the object support 11′ is pressed onto the base plate 1 under the influence of the weight of the fresh concrete. It is already formed on the object support 11′ and is supported on the base plate 1. Thus, the spacer 17 ensures that the cavity 3 remains open between the object holder 11′ and the base plate 1 and is not interrupted by the contact of the object holder 11′ on the base plate 1. Otherwise, the vacuum could possibly not spread uniformly on the underside, which faces away from the concrete, of the object support 11′ in the formwork element and does not hold the glass beads 35 in the desired position during the concreting process.

[0061] FIGS. 5a to 5i show a selection of possible forms of surfaces 31, 37 or concrete components 30 designed according to the invention: FIG. 5a schematically shows a plate-shaped concrete component 30 whose one surface 31 is occupied by glass beads 35. The glass beads 35 are permanently incorporated and fastened into the concrete component 30 and are used as reflectors of incident light. Thus, they not only shape the surface 31, but also functionalize it, by giving it a reflective function. Their reflective function is thus much more durable than that of reflective paints.

[0062] FIG. 5d also shows a flat concrete component 30 whose one surface 31 is not even but rather corrugated in section and is also occupied by glass beads 35. Thus, the reflecting effect of the surface 31 can be extended to a larger angular range. The production of the concrete component 30 of FIG. 5d with a formwork element according to the invention is shown schematically in FIG. 4.

[0063] FIGS. 5b and 5e show a cross-section through a square concrete component, the extension of which can be arbitrarily large, orthogonal to the drawing plane. The concrete components 30 can accordingly be, for example, a support or a stair step, according to FIG. 5b also a support beam. The concrete components 30 according to FIGS. 5b and 5e can be produced by formwork elements according to FIGS. 1 to 3, wherein they can be produced in any case with vertically standing functionalized surfaces 31, the component 30 according to FIG. 5b possibly also horizontal. That is because the formwork element according to the invention makes it possible to also hold the glass beads 35 on a vertical surface before and during the concreting operation.

[0064] The concrete components 30 shown in section according to FIGS. 5c and 5f can be, for example, stair steps, moldings for a façade or support linings. They enable existing components to be retrofitted with a functionalized surface 31, in the present case with coated with glass beads. Its production effort is consequently less than that of a complete support or stair step with the desired functionalized surface. Together with a concrete component 30 according to FIG. 5a, it is also possible to functionalize large or strongly profiled surfaces, in which they are coated by concrete components 30 according to FIGS. 5a, 5c, and 5f (and, if appropriate, further, for example, convex or concave curve-shaped finished parts).

[0065] FIG. 5g shows a concrete component 30 with an inlet niche 33 and an empty pipe 34 connected thereto and concreted. The inlet niche 33 can be produced in a formwork element according to the method described in FIG. 3 for positioning an opposing formwork element 20 on the object carrier 11 (see FIG. 3).

[0066] Finally, FIG. 5i shows a concrete component 30 having a surface 31 which is shaped as a saw-tooth or shed-roof shape and carries several identically shaped riders 37. In principle, vacuum formworks according to the invention are not absolutely necessary, but are useful, for this and for the concrete component 30 according to FIG. 5h. Because the advantage of their use in the production of concrete components 30 according to FIGS. 5g to 5i lies in their flexibility, in their simple equipping with opposing formwork elements for the configuration of the recess 33, of the passage 36 (FIG. 5g) or the uniform or even non-uniform shape of the rider 37 according to FIG. 5i and its problem-free multiple usability. When flexible dies are used as object holders 11 or 11′ (see FIGS. 1, 3 and 4), their two- or three-dimensional shapes can also be simply altered and thus also be flexibly used for a large number of different concrete moldings.

[0067] FIG. 6 illustrates the use of the formwork element according to the invention within a conventional system formwork 40: between two vertically projecting formwork walls 41, which are supported by means of conventional anchors 42 at a uniform distance from each other and via push-pull props 43 like a positional securing on a subgrade, formwork elements 45 according to the invention are attached to the concrete-facing inner sides of the formwork walls 41. They are connected to a vacuum generating device via vacuum lines 46 through the conventional formwork shell of the formwork walls 41. The anchors 42 clamp down the formwork elements 45 and are therefore sealed pressure-tight with an anchor passage in the form of a rubber seal or a fluid-tight sleeve. After assembly of the formwork elements 45 of the system shell 40 and the application of vacuum via the vacuum lines 46, the concrete can be introduced into the system shell 40 in a conventional manner and compressed. Even before reaching its green strength, the vacuum generation can be switched off and the concrete can continue to harden. The concrete wall to be created can then be conventionally switched off. The formwork elements 45 can be used for a further use after a cleaning.

[0068] Since the preceding formwork elements described in detail are exemplary embodiments, they can be modified in a conventional manner by a person skilled in the art without departing from the scope of the invention. In particular, the concrete embodiments of the object holders can also follow a different form from the one described here. Likewise, the spacer can be designed in a different form if this is necessary for space or design reasons. Furthermore, the use of the indefinite articles “a” or “an” does not exclude the fact that the relevant features can also be present several times or more.

LIST OF REFERENCE NUMBERS

[0069] 1 Base plate [0070] 2 Side walls [0071] 3 Cavity [0072] 4 Front side [0073] 5 Surface [0074] 6 Upper side [0075] 7 Connection [0076] 8 Bore [0077] 9 Groove [0078] 10 Grating holder [0079] 11, 11′ Object support [0080] 12 Clamping bar [0081] 13 Hexagon screw [0082] 14 Spot welding mesh [0083] 15 Round cord [0084] 16 Through holes [0085] 17 Spacer [0086] 20 Opposing formwork element [0087] 21 Rubber seal [0088] 22 Wooden support [0089] 30 Concrete component [0090] 31 Surface [0091] 32 Formwork element [0092] 33 Niche [0093] 34 Empty pipe [0094] 35 Glass bead [0095] 36 Passage [0096] 37 Rider [0097] 40 System formwork [0098] 41 Formwork wall [0099] 42 Anchor [0100] 43 Push-pull prop [0101] 45 Formwork element [0102] 46 Vacuum line