WO2020074617A1

WO2020074617A1 - Method and semi-finished product for the production of a concrete double-wall element

Info

Publication number: WO2020074617A1
Application number: PCT/EP2019/077427
Authority: WO
Inventors: Martin Schwarzenbeck; Otto Schwarzenbeck; Josef Binsteiner
Original assignee: Martin Schwarzenbeck & Co. Bauunternehmen Und Betonwerk Gmbh & Co. Kg
Priority date: 2018-10-10
Filing date: 2019-10-09
Publication date: 2020-04-16
Also published as: EP3863820C0; EP3863820A1; EP3863820B1

Abstract

The invention relates to a method for producing a concrete double-wall element comprising two spaced-apart concrete shells (2a, 2b) that are connected to one another via connecting means (3). In order to prevent the first concrete shell (2a) from shifting relative to the fresh concrete (10b) of the other concrete shell during the production of the double-wall element (1), a fixing device (20) is set into the concrete of the first concrete shell (2a), which has an anchoring element (23) on a second end section (22) spaced apart from the concrete shell (2a). When placing the first concrete shell (2a) on the fresh concrete layer (10b), this anchoring element (23) forms a secure connection to a pallet (5b) carrying the fresh concrete layer (10b) and thereby secures the first concrete shell (2a) relative to the fresh concrete layer (10b).

Description

Process and semi-finished product for the production of a concrete double wall element

The invention relates to a method for the production of concrete double wall elements according to the preamble of claim 1. Furthermore, the invention relates to a semi-finished product which is used in the production of such a concrete double wall element.

Precast concrete parts are often manufactured in two steps, which take place in spatially separate locations. First of all, so-called concrete double-wall elements are produced in a precast plant, which comprise a first shell and a second shell made of reinforced concrete. There is a cavity between the two shells, which can optionally be provided with insulating materials. These prefabricated double-wall elements are transported to the construction site and fixed there in the desired end position. The cavity between the first and second shell is then filled with concrete.

The production of the double wall elements in the precast concrete plant typically takes place in several process steps using a so-called pallet circulation system. In a first step, a so-called first shell is produced and cured in a drying chamber. In this first shell composite materials are concreted, which are typically distributed over the entire wall element, act as spacers and define the wall thickness of the component in the later component. Once the first shell has hardened, it is turned through 180 ° and placed on a layer of liquid concrete (fresh concrete) that forms the (still unhardened) second shell. The spacers concreted into the first shell rest on the lower formwork when the first shell is placed in the fresh concrete of the second shell. The assembly of the first and second shell is again brought into the drying chamber in order to harden the second shell. The concrete double wall element produced in this way is then removed from the pallet in a demoulding station. In the production of concrete double wall elements in the pallet circulation system, the concrete shells and concrete elements to be produced are stored on movable pallets that are moved to different work stations for the different work steps. This procedure enables very efficient production, but in the work step of placing the first shell on the fresh concrete of the second shell there is the difficulty that the hardened first shell rests with its entire weight on the punctiform spacers. While the process step of placing the first shell is machine-controlled and highly precise, it can be combined in the subsequent compacting process and in particular when the pallet carrying the fresh concrete is transferred to a next work station due to the braking and acceleration forces that occur the inertia of the first shell causes the hardened first shell to shift relative to the fresh concrete of the second shell. If such misalignments are noticed before the second shell of the double wall part has hardened, they can be corrected by hand, but this involves a great deal of effort. Such misalignments are often only noticed when the walls are installed on the construction site. At this point in time, the incorrect positions can no longer be corrected, but must be compensated for by increased assembly effort.

The invention is therefore based on the object of proposing a method in which the above-described misalignments of the two individual concrete shells with respect to one another are avoided or at least reduced. Furthermore, a flat sheet in the form of a specially designed single shell is to be provided, which is designed in such a way that when a further single shell is attached to this flat sheet, misalignments of the two single shells relative to one another are avoided.

This object is achieved by a method with the features of the independent claim 1. The object is further achieved by a flat fabric with the features of the independent claim 8. The subclaims relate to advantageous developments and variants of the invention. In a method according to the invention for producing a double wall concrete element, a fixing device with a first and a second end section is used for the relative positioning of the two individual shells. The first end section of the fixing device is concreted together with the connecting means in the course of the production of the first concrete shell. The first end section is embedded in the liquid concrete of the first concrete shell in such a way that the second end section of the fixing device, which is not concreted in, both projects laterally beyond the contour of the first concrete shell and also projects vertically above it. An anchor element is attached to the second end section. The second end section or the anchor element are dimensioned in such a way that the second end section provided with the anchor element protrudes from the first concrete shell approximately as far in the normal direction of the first concrete shell as the connecting means which together with the fixing device can be concreted into the first concrete shell. When the first concrete shell, which is turned by 180 °, is placed on the fresh concrete layer of the second concrete shell, the anchor element comes into engagement with the pallet carrying the fresh concrete layer and connects the first concrete shell to this pallet so that it cannot move. By means of the fixing device, the first concrete shell is thus fixed in relation to the pallet carrying the fresh concrete layer, so that no changes in position of the first concrete shell relative to the pallet can occur during the shaking of the first concrete shell and during the transport of the pallet into the hardening station or drying chamber. The connection of the fixing device with the one carrying the fresh concrete layer

The pallet is preferably an easily detachable connection, so that the anchor element can be detached from the pallet without great effort after completion of the double wall element and the pallet can be used without any residues from the fixing device. For example, the anchor element can in particular be a permanent magnet that can be fixed to the (metallic) pallet by means of magnetic force and is removed without residue after removal of the finished double wall element, for example by removing the formwork. The part of the fixing element comprising the two end sections is preferably a bent rod, in particular a bent steel rod. This enables a particularly simple and inexpensive design of the fixing element. The anchor element is preferably detachably fastened to the second end section of this steel rod and is only fastened to the second end section after the first end section has been concreted in (and the first concrete shell has hardened). This makes it easier to flatten the fixing element during the production of the first concrete shell, because only the steel rod (which is comparatively light in weight) needs to be concreted in, while the (heavier) anchor element attaches to the steel rod only later, before the first concrete shell is placed on the fresh concrete layer needs to be. The anchor element is preferably connected via a thread to the second end section of the fixing device or the steel rod. During the production of the first concrete shell, the first end section of the fixing device is introduced into the fresh concrete of the first shell in the desired position / orientation of the fixing device, and the fixing device is then brought together with the pallet carrying this fresh concrete into the hardening furnace in order to fix the fixing device in anchor this position / orientation in the first concrete shell. In order to ensure that the fixing device is reliably concreted in the desired installation position during transport and the curing process of the first individual shell, it can be fixed with the aid of a support device (eg mechanically or magnetically). When the first concrete shell is completely hardened, the anchor element is (or when using a detachable anchor element) placed on the second end section of the fixing device or plugged on or screwed on. The first concrete shell is then turned through 180 ° using a turning system and inserted into the fresh concrete of the second half shell. When the first half-shell is lowered, the anchor element of the fixing device establishes a (for example magnetic) connection with the pallet carrying the fresh concrete, as a result of which the fixing device and thus the first concrete shell is fixed relative to the pallet. Now moves the pallet after Turning process, the fixing device holds the first concrete shell in the correct position in relation to the fresh concrete layer applied to the pallet. A horizontal slipping of the first concrete shell compared to the fresh concrete of the second

This effectively prevents the concrete shell from being transported or curing the second concrete shell.

A folded sheet for fixing a double wall concrete element comprises a hardened, flat concrete layer with composite material embedded in sections in this concrete layer and a fixing device which is concreted into the concrete layer in a first end section and has a second end section which is laterally offset from the surface of the concrete layer protrudes. The second end section is provided with an anchor element (releasably or non-releasably connected to this second end section), which in particular can comprise a permanent magnet. The sheet is used as the first concrete shell when a concrete double wall element is positioned; the fixing device of the sheet makes it possible to fix the sheet on a pallet carrying a fresh concrete layer in the manner described above.

Exemplary embodiments and variants of the invention are explained in more detail below with reference to the drawing. Show it:

FIG. 1 shows a schematic sectional illustration of a concrete double wall element produced using the method according to the invention;

FIG. 2 shows a schematic flow diagram of a method for setting the

Concrete double wall element of Figure 1;

3a shows a schematic sectional illustration of a cast first shell on a pallet (corresponding to method step A in FIG. 2);

FIG. 3b shows a schematic sectional illustration of a sheet made by curing the cast first shell of FIG. 1; FIG. 3 c shows a schematic sectional illustration of the hardened flat sheet turned by 180 ° over a cast second shell (corresponding to method step C in FIG. 2);

FIG. 3d shows a schematic sectional illustration of the turned sheet-metal product deposited on the cast second shell (corresponding to method step D in FIG. 2).

FIG. 3e shows a schematic sectional illustration of the assembly of first and second shells produced by curing the second shell;

FIG. 1 shows a schematic representation of a concrete double-wall element 1 with two flat shells 2a, 2b made of hardened concrete 1, which are connected by means of composite 3 and fixed at a predetermined distance from one another by means of composite 3. A flute space 29 is formed between the two concrete shells 2a, 2b and is filled with liquid concrete in a later process step, not described here, at a place of installation, in particular at a construction site, to form a concrete wall.

FIG. 2 illustrates a basic process sequence when the concrete double wall element 1 of FIG. 1 is set; Individual process steps are shown in FIGS. 3a-3e. The concrete position of the double-walled concrete element 1 takes place with the aid of pallets 5a, 5b, which successively pass through several stations of a production line (not shown in the figures). The displaceability of the pallets 5a, 5b in the course of the freezing position of the concrete double-wall element 1 is indicated in FIGS. 3a-3f by transport rollers 8 below the pallets 5a, 5b.

In a first process step (step A), formwork elements 6a 'are attached to a first pallet 5a; the entirety of these formwork elements 6a 'forms a formwork 6a which encloses an interior space 7a to be filled with liquid concrete and thus corresponds to the outer and inner contour of the concrete double wall element 1 to be produced (step A). In the formed by the formwork elements 6a ' Interior space 7a (reinforcement mats not shown in the figures) can be inserted before liquid concrete 10a (so-called fresh concrete) is poured into interior space 7a (step B, see FIG. 3a). In the still unhardened liquid concrete 10a, compound means 3, for example lattice girders, are inserted, which later, in the concrete double wall element 1 to be manufactured, connect the two concrete shells 2a, 2b with one another (see FIG. 1). Peaks 4 of these composite means 3 protrude upward from the liquid concrete 10a and in this way define the width of the flute space 29 inside the concrete double wall element 1 to be produced. Furthermore, a fixing device 20 with two end sections 21, 22 is placed in the still uncured liquid concrete 10a introduced in such a way that the first end section 21 is embedded in the liquid concrete 10a, while the second end section 22 projects both vertically (in a connecting direction 15) and laterally (perpendicular to the connecting direction 15) over the formwork 6b. The

In the exemplary embodiment in FIG. 3a, fixing device 20 comprises an S-shaped metal rod 26 with two approximately parallel, spatially offset end sections 21, 22, the first end section 21 of which is inserted into the liquid concrete 10a, while the second end section 22 is approximately protrudes parallel to the connection direction 15 from the pallet 5a and is located outside the outer contour of the formwork 6a (see FIG. 3a). The second end section 22 has a fastening region 25 for fastening an anchor element 23, for example a permanent magnet. The anchor element 23 can be firmly connected to the second end section 22 (for example by means of an adhesive or compression connection). Preferably, however, the anchor element 23 is - as shown in the exemplary embodiment of FIGS. 3b - 3e - releasably attached to the second end section 22 and is only attached to the second end section in a later process step (see FIG. 3c). In the present exemplary embodiment, the second end section 22 in the fastening region 25 is provided with an external thread onto which the anchor element 23 can be screwed.

The pallet 5a equipped in the manner described is now brought into a curing station, in which the liquid concrete 10a forms a first concrete shell 2a (first shell) hardens (step C). In order to hold the fixing device 20 in the desired position and orientation prior to the hardening of the liquid concrete layer 7a, a supporting device 30 is provided, which fixes the fixing device 20 during transport into the flare station and during the hardening of the liquid concrete 10a in the desired position and orientation. In the course of the hardening of the concrete, the fixing device 20 is firmly concreted into the first shell 2a in the region of its first end section 21. In order to ensure good anchoring of the first end section 21 in the first shell 2a, the first end section 21 can have bends / curvatures and / or material thickenings, be provided with a surface structure, etc.

After the liquid concrete 10a has hardened, the support device 30 can be removed, since the fixing device 20 is now firmly anchored in the hardened concrete layer 2a. Furthermore, the magnetic armature element 23 is screwed onto the free end of the second end section 22 of the fixing device 20.

Process steps A to C create a semifinished product 9 (intermediate product) for producing the concrete double wall element 1 of FIG. 1. The semifinished product 9 comprises the hardened first shell 2a with the composite means 3 concreted in sections, the tops 4 of which in the connecting direction 15 from the

Protruding concrete layer 2a, as well as the fixing device 20 concreted in sections, the second end section 22 of which projects laterally offset in relation to the surface of the concrete layer 2a in the connection direction 15. Such a semi-finished product 9 is shown in FIG. 3b.

In a process step A ', formwork elements 6b' for formwork 6b are attached to a second pallet 5b, which also corresponds to the outer and inner contour of the concrete double wall element 1 to be produced, but which is arranged in the opposite direction to the formwork 6a of the first pallet 5a. Reinforcement mats can first be inserted into the interior space 7b formed by the shuttering elements 6b '. Liquid concrete 10b is then poured into the interior 7b (process step D). In a process step E taking place simultaneously or at different times, the hardened first shell 2a located on the first pallet 5a is turned by 180 ° with the aid of a turning device, so that the tips 4 of the composite means 3 project downward (see FIG. 3b). Subsequently, the first shell 2a is placed in a precalculated manner on the liquid concrete layer 10b of the second pallet 5b (process step F). The crests 4 of the composite means 3 sink into the liquid concrete layer 10b (see FIG. 3d). At the same time, the anchor element 23 of the fixing device 20 comes into contact with the surface of the second pallet 5b. In order for this contact between the anchor element 23 and the surface of the second pallet 5b to take place, the length of the second end section 24 or the anchor element 23 is dimensioned such that the side 24 of the anchor element facing away from the first shell 2a is at approximately the same height above the level of the first - Shell 2 protrudes like the tips 4 of the composite means 3.

Since the anchor element 23 is designed as a permanent magnet and the second pallet 5b (at least in the area of impact of the anchor element 23) consists of a magnetic material, the anchor element 23 is magnetically attracted to the surface of the pallet 5b and thus the entire fixing device 20 is magnetically firmly connected to the second pallet 5b. And since the fixing device 20 is embedded in the first concrete shell 2a, the first concrete shell 2a is thus also fixed to the second pallet 5b.

The second pallet 5b with the liquid concrete layer 10b and the first shell 2b mounted thereon is then brought into the hardening station. Due to the fixing of the first concrete shell 2b to the second pallet 5b by means of the fixing device 20, displacements of the first concrete shell 2b with respect to the second pallet 5b are prevented during this transport. In the hardening station, the liquid concrete 10b poured into the interior 7b of the second pallet 5b is hardened into a second concrete shell 2b (second shell) (step G). First shell 2a and second shell 2b are now firmly connected to each other, displacements of the two Shells 2a, 2b relative to one another are prevented by the composite means 3 concreted in on both sides (FIG. 3e).

In a next process step H, the anchor element 23 of the fixing device 20 is mechanically separated in order to be able to remove the concrete double wall element 1 from the pallet 5b. The fixing device 20 is preferably severed at a location 27 in the hollow space 29 of the concrete double wall element 1 (see FIGS. 3e and 1). In this way it is ensured that the stub 28 of the fixing device 20 remaining on the concrete double wall element 1 is completely embedded in concrete during the subsequent filling of the hollow space 29 at the construction site and corrosion of the stub 28 is avoided.

The anchor element 23 magnetically fixed on the second pallet 5b can then be removed - together with the formwork elements 6b '-, unscrewed from the separated end of the fixing device and used as part of a further fixing device when another concrete double-wall element is fixed.

Claims

1. A method for producing a concrete double wall element (1), comprising a first concrete shell (2a) and a second concrete shell (2b) with the steps: a. Pouring liquid concrete (10a) and inserting composite means (3) projecting from this liquid concrete (10a) in sections into an interior (7a) formed by a formwork (6a) on a first pallet (5a) (step B);

b. Curing this liquid concrete layer (10a) provided with the composite means (3) to create a first concrete shell (2a) (step C); c. Pouring liquid concrete (10b) into an interior space (7b) formed by a formwork (6b) on a second pallet (5b) (step D); d. Turning the first concrete shell (2a) (step E) and placing it on the liquid concrete layer (10b) of the second pallet (5b) (step F);

e. Hardening of the liquid concrete layer (10b) located on the second pallet (5b) to create a second concrete shell (2b) firmly connected to the first concrete shell (2a) via the connecting means (3) (step G),

characterized,

f. that in step B a fixing device (20) is inserted into the liquid concrete (10a) in such a way that a first end section (21) of the fixing device (20) is embedded in the liquid concrete (10a) and a second end section (22) laterally the formwork (6a) protrudes,

G. and that in the course of depositing the first concrete shell (2a) on the liquid concrete layer (10b) of the second pallet (5b) (step F), an anchor element (23) provided on the second end section (22) of the fixing device (20) on the second pallet (5b) is attached.

2. The method according to claim 1,

characterized in that the anchor element (23) provided on the second end section (22) of the fixing device (20) is releasably attached to the second pallet (5b).

3. The method according to claim 1 or 2,

characterized in that the anchor element (23) provided on the second end section (22) of the fixing device (20) comprises a permanent magnet which is attached to the second pallet (5b) by means of magnetic force.

4. The method according to any one of claims 1 to 3,

characterized in that a steel rod (26) with an anchor element (23) attached to the end (25) of this steel rod (26) is used as the fixing device (20).

5. The method according to any one of claims 1 to 4,

characterized in that the anchor element (23) is releasably attached to the second end section (22) of the fixing device (20).

6. The method according to claim 5,

characterized in that the anchor element (23) is fastened via a thread to the second end section (22) of the fixing device (20).

7. The method according to any one of claims 1 to 6,

characterized in that the fixing device (20) is fixed in position by means of a support device (30) during the hardening of the first concrete shell (2b) (step C).

8. flaling product (9) for the positioning of a concrete double-wall element (1), the flaling product (9) comprising a hardened, flat concrete shell (2a) and, in sections, composite means (3) embedded in this concrete shell (2a), wherein Protrusions (4) of these composite means (3) protrude from the concrete shell (2a) in a connecting direction (15),

characterized,

a. that the semifinished product (9) further comprises a fixing device (20) with a first end section (21) and a second end section (22), b. the first end section (21) being embedded in the concrete shell (2a) c. and the second end section (22) projects laterally offset to the surface of the concrete shell (2a) in the connecting direction (15).

9. semi-finished product (9) according to claim 8,

characterized in that a fastening area (25) of the second end section (22) is provided with an anchor element (23), the side (24) of the concrete shell (2a) facing away from it in the connecting direction (15) approximately the same distance from the concrete shell (2a) protrudes like the composite means (3).

10. semi-finished product (9) according to claim 9,

characterized in that a magnetic armature element (23) is fastened in the fastening region (25) of the second end section (22).

11. semi-finished product (9) according to claim 10,

characterized in that the anchor element (23) is detachably, in particular by means of a thread, fastened in the fastening region (25) of the second end section (22).