CONCRETE DOUBLE WALL ELEMENT AS WELL AS SEMI-CONTACT PRODUCT AND SUPPORTING DEVICE FOR ITS MANUFACTURE

Description

[0001] The invention relates to a support device for the production of a concrete double-wall element according to the preamble of claim 1. The invention further relates to a semi-finished product produced using this support device and to a concrete double-wall element.

[0002] The production of precast concrete elements often takes place in two steps at separate locations. First, so-called double-wall concrete elements are produced in a precast concrete plant. These elements consist of a first shell and a second shell made of reinforced concrete. A cavity exists between the two shells, which may be filled with insulation. These prefabricated double-wall elements are then transported to the construction site and fixed in their final position. Finally, the cavity between the first and second shells is filled with concrete.

[0003] The production of double-wall elements in the precast concrete plant typically takes place in several process steps using a pallet circulation system. In the first step, a so-called first shell is produced and cured in a drying chamber. Bonding agents and / or double-wall spacers are embedded in this first shell. These are typically distributed across the entire wall element, act as spacers, and define the wall thickness of the finished component. Once the first shell has cured, it is rotated 180° and placed onto a layer of liquid concrete (fresh concrete), which forms the (still uncured) second shell. The spacers or double-wall spacers embedded in the first shell rest on the lower formwork when the first shell is placed into the fresh concrete of the second shell. The assembly of the first and second shells is then returned to the drying chamber to cure the second shell.The concrete double-wall element produced in this way is then removed from the pallet at a demolding station.

[0004] To enable adjustment of the distance between the two shells during the production of the concrete double-wall element, DE 11 2010 003 523 T5 proposes embedding a sleeve with an internal thread in the first shell, into which a bolt with an external thread can be screwed. This bolt is screwed into the first shell until its tip protrudes to a depth corresponding to the desired shell spacing. When the first shell is then placed onto the uncured second shell, the bolt acts as a spacer between the first and second shells during the curing process. This document discloses a concrete double-wall element according to the preamble of claim 9 and a semi-finished product according to the preamble of claim 12. A similar design for adjusting the shell spacing is also known from EP 2 775 063 A1.

[0005] In the production of double-wall concrete elements in the pallet circulation system, the concrete shells and elements to be manufactured are stored on movable pallets, which are moved to different workstations for the various work steps. This procedure enables very efficient production, but presents a difficulty during the step of placing the first shell onto the fresh concrete of the second shell: the hardened first shell rests with its entire weight on the point-shaped spacers or double-wall spacers.While the process of placing the first shell is machine-controlled and highly precise, the subsequent compaction process, and especially the transfer of the pallet carrying the fresh concrete to the next workstation, can lead to displacement of the hardened first shell relative to the fresh concrete of the second shell. This displacement is caused by the braking and acceleration forces combined with the inertia of the first shell. If such misalignments are noticed before the second shell of the double-wall section has hardened, they can be corrected manually, but this is a very time-consuming process. Often, however, such misalignments are only noticed during the assembly of the walls on the construction site. At this point, the misalignments can no longer be corrected and must be compensated for by increased assembly effort.

[0006] A method for avoiding or reducing the misalignment of the two concrete shells described above is described in DE 10 2018 124 980 B3. This publication discloses a support device for the precise relative positioning of two concrete shells during the production of a double-wall concrete element according to the preamble of claim 1.

[0007] A fixing device is used to position the two individual shells relative to each other. The first end section of this device is embedded in the first concrete shell during its production, along with the connecting elements. A second end section of the fixing device extends both laterally and vertically beyond the first concrete shell. An anchor element is attached to this second end section. When the first concrete shell is turned over and placed on the fresh concrete layer of the second concrete shell, this anchor element engages with the pallet supporting the fresh concrete layer, thus securing the first concrete shell to the pallet and preventing any displacement. This ensures that no further changes in the position of the first concrete shell relative to the pallet can occur during the vibrating process and during the transport of the pallet to the curing station or drying chamber.

[0008] After the double-wall element has fully hardened, a portion of the embedded fixing device protruding from the element is cut off, leaving a stub of the fixing device inside the double-wall element. The fixing device is thus destroyed, necessitating the production of a new one for each subsequent double-wall element. This is costly and incurs additional material expenses. Therefore, there is an interest in further developing the fixing device to ensure maximum reusability.

[0009] The invention is based on the objective of further developing the fixing device known from DE 10 2018 124 980 B3 in such a way that it can be reused with minimal material and labor expenditure and used to manufacture various double-wall elements. Furthermore, a concrete double-wall element and a semi-finished product in the form of a specially designed single shell are to be provided, which are manufactured using such an improved fixing device.

[0010] This problem is solved by a support device with the features of independent claim 1. The problem is further solved by a concrete double-wall element with the features of independent claim 9 and a semi-finished product with the features of independent claim 12. The dependent claims relate to advantageous further developments and variants of the invention.

[0011] The support device according to the invention, which serves for the precise relative positioning of two concrete shells during the production of a double-wall concrete element, comprises a fixing element with a first end section that is embedded in the first concrete shell during its production / curing. The support device further comprises an anchor element with which the fixing element can be detachably attached to a pallet supporting the second concrete shell. When the first concrete shell, rotated by 180°, is placed onto the fresh concrete layer of the second concrete shell, a firm connection is established between the two pallets supporting the concrete layers by means of the fixing element and the anchor element.The fixing element and anchoring element thus work together in such a way that they fix the first concrete shell relative to the pallet supporting the fresh concrete layer, so that no changes in position of the first concrete shell relative to the pallet can occur during the vibration of the first concrete shell and during the transport of the pallet to a hardening station or drying chamber.

[0012] To ensure high reusability of the support device, the first end section of the fixing element, which is to be embedded in the first concrete shell, is equipped with a sleeve that is detachably attached to the end section of the fixing element. The sleeve is designed and positioned in such a way that when the fixing element is cast into the first concrete shell, only this sleeve, and not the rest of the fixing element, comes into contact with the concrete. After the concrete shell has hardened, this sleeve is embedded in the concrete shell and thus remains there. The fixing element can then be pulled out of the sleeve and, after completion of the manufacturing process of the double-wall concrete element, is available for the production of further concrete shells.

[0013] The sleeve is preferably made of a plastic material and is provided with longitudinal and / or transverse ribs on its outer surface. The ribs stabilize the sleeve against deformation and ensure good anchoring of the sleeve in the first concrete shell.

[0014] To ensure that the fixing element, or the sleeve attached to it, is reliably embedded in the desired position during the curing process of the first concrete shell, it is advantageous if the fixing element can be detachably attached (magnetically and / or mechanically) to a pallet supporting the first concrete shell in a support area. Advantageously, the fixing element has a permanent magnet in the support area, so that it can be fixed to the (metallic) pallet or a (metallic) formwork located on this pallet by magnetic force and held in the desired position relative to the pallet and the first concrete shell on it.

[0015] The fixing element and anchor element can be permanently connected. Advantageously, however, the fixing element and anchor element are separate elements that can be detachably connected. In this case, the fixing element has a base section where it can be attached to the anchor element. This base section advantageously has the shape of a hemisphere, which allows for simple, secure clamping of the base section in the anchor element. The connection is preferably made using a snap-fit ​​connector.

[0016] The anchor element is preferably attached to the pallet supporting the fresh concrete layer by means of an easily detachable connection, so that the anchor element can be removed from the pallet without much effort after completion of the double-wall element and the pallet can be reused without leaving any residue from the fixing device. In particular, the anchor element can include a permanent magnet that can be fixed to the (metallic) pallet by magnetic force and is removed without residue after removal of the finished double-wall element – ​​for example, when removing the formwork.

[0017] A semi-finished product according to the invention, produced using such a support device, comprises a planar concrete shell in which shear connectors are embedded in such a way that the crests of these shear connectors protrude from the concrete shell in a connection direction. The semi-finished product further comprises, in an area near the edge, a sleeve embedded in the concrete shell for receiving a fixing element, which serves to fix the semi-finished product during a further processing step for the production of a concrete double-wall element.

[0018] The sleeve is embedded in an area near the edge and projects obliquely into the concrete shell. It has an opening located on the inner side of the concrete shell facing the domes of the shear connectors. The sleeve is preferably made of a plastic material and is provided with stabilizing longitudinal and / or transverse ribs.

[0019] A concrete double-wall element according to the invention, manufactured using such a semi-finished product, comprises two flat concrete shells in which shear connectors are embedded in sections. These connectors serve to join and space the concrete shells. A sleeve for receiving a fixing element is cast into one of these concrete shells in a region near the edge. This sleeve is located in a region near the edge of the concrete shell and projects obliquely from the inner surface of the first concrete shell facing the second concrete shell. It has an opening located on an inner surface facing the opposite concrete shell and oriented towards the edge of the first concrete shell. The sleeve is preferably made of a plastic and is provided with stabilizing longitudinal and / or transverse ribs.

[0020] Exemplary embodiments and variants of the invention are explained in more detail below with reference to the drawing. The drawing shows: Figure 1 is a schematic sectional view of a concrete double-wall element according to the invention, which is constructed using a Figure 2a - 2c shown support device was manufactured; Figures 2a, 2b schematic representations of a support device according to the invention with fixing element and anchor element in separate ( Figure 2a ) and associated ( Figure 2b ) State; Figure 2c: a schematic perspective view of the anchor element of Figure 2a; Figures 3a - 3e: individual steps in the production of a double-wall element: Figure 3a: a schematic sectional view of a first concrete shell on a pallet; Figure 3e: a schematic sectional view of a double-wall element formed by the hardening of the cast first concrete shell. Figure 3a produced semi-finished product; Figure 3 shows a schematic sectional view of the hardened semi-finished product turned 180°. Figure 3bover a layer of fresh concrete; Figure 3 a schematic sectional view of the inverted semi-finished product placed on the layer of fresh concrete; Figure 3 a schematic sectional view of the concrete double-wall element produced by hardening the fresh concrete.

[0021] Figure 1 Figure 1 shows a schematic representation of a concrete double-wall element 1 with two flat shells 2a, 2b made of hardened concrete, which are connected by shear connectors 3 and fixed at a predetermined distance from each other using double-wall spacers 3'. A cavity 15 is formed between the two concrete shells 2a, 2b, which is filled with liquid concrete in a later process step, not described in detail here, at a construction site to form a concrete wall.

[0022] In the first concrete shell 2a of the concrete double-wall element 1, a sleeve 23 made of a plastic is embedded, which - as described in detail below - is designed to receive a Figures 2a and 2b The support device 40 shown serves as a support device during the manufacture of the concrete double-wall element 1. The sleeve 23 is embedded in an area 11a near the edge of the concrete shell 2a in such a way that the outer surface 26 of the sleeve 23 is partially encased in concrete. The opening 26' of the sleeve 23 faces the edge 12a of the concrete shell 2a, and the sleeve 23 projects obliquely from the inner surface 13a of the first concrete shell 2a, which faces the second concrete shell 2b.

[0023] Figures 2a and 2bFigure 1 shows schematic representations of the support device 40 with a fixing element 20 and an anchor element 30, which are detachably connected to each other. For this purpose, the fixing element 20 is provided with a foot part 25, which can be locked into the anchor element 30 in a displacement-proof manner. Figures 2a shows fixing element 20 and anchor element 30 in a separate state, Figure 2b in a state in which fixing element 20 and anchor element 30 are connected and locked. Figure 2c shows a perspective detail view of anchor element 30.

[0024] Figures 3a to 3e illustrate individual process steps of a process flow for the production of the concrete double-wall element 1 of the Figure 1 and as well as the use of the support device 40 used therein Figures 2a, 2b and 2cThe concrete double-wall element 1 is manufactured using pallets 5a, 5b, which successively pass through several stations of a production line (not shown in the figures). The mobility of the pallets 5a, 5b during the manufacture of the concrete double-wall element 1 is shown in the Figures 3a - 3e indicated by transport rollers 8 below pallets 5a, 5b.

[0025] In a first process step, formwork elements 6a and double-wall spacers 3' are attached to the first pallet 5a. The entirety of the formwork elements 6a forms a formwork that encloses an interior space 7a to be filled with liquid concrete and corresponds to the outer and inner contours of the concrete double-wall element 1 to be produced. Liquid concrete 10a (so-called fresh concrete) is poured into this interior space 7a ( Figure 3a). Composite elements 3, for example lattice girders, are inserted into the still unhardened liquid concrete 10a, which later, in the concrete double-wall element 1 to be produced, connect the two concrete shells 2a, 2b to each other (see Figure 1 ). The domes 4 of these composite elements 3 protrude upwards from the liquid concrete 10a.

[0026] Furthermore, the fixing element 20 of the in is placed on the formwork 6a. Figure 2aThe support device 40 shown is positioned such that a first end section 21 of the fixing element 20 – as well as the shear connectors 3 and the double-wall spacers 3' – projects section by section into the fresh concrete 10a of the first concrete shell 2a. The first end section 21 is inserted at its end into a sleeve 23, and the end section 21 and the sleeve 23 are dimensioned such that only portions of the sleeve 23, and not the remainder of the first end section 21, are immersed in the fresh concrete 10a. The sleeve 23 is preferably made of a plastic and provided with longitudinal and / or transverse ribs 24 (see Figure 1). Figure 2a These ribs 24 provide mechanical stabilization of the sleeve 23, but also serve to ensure anchoring and thus the retention of the sleeve 23 in the first concrete shell 2a after removal of the fixing element 20.

[0027] A second end section 22 of the fixing element 20, designed as a curved metal rod 29, projects both vertically (in a Figure 3a The fixing element 20 extends both in the direction of connection 14 (shown as an arrow) and laterally (perpendicular to the direction of connection 14) beyond the formwork 6a and has a foot section 25 at its end, which serves to attach the fixing element 20 to the anchor element 30. For temporary attachment of the fixing element 20 to the pallet 6a, which carries the fresh concrete 10a, a permanent magnet 28 is also provided on the fixing element 20. This magnet is located in a support area 27 of the fixing element 20 opposite the formwork 6a. In the present embodiment, the support area 27 is placed on the formwork 6a, which is made of a magnetizable material (e.g., steel), and ensures a stable hold of the fixing element on the pallet 6a.

[0028] The one equipped in the manner described, in Figure 3aThe pallet 5a shown is now moved to a curing station where the liquid concrete 10a hardens to form a first concrete shell 2a (initial shell). During transport to the curing station and during the curing of the liquid concrete 10a, the fixing element 20 is held in the desired position and orientation on the pallet 5a by the permanent magnet 28. As the concrete cures, the bonding elements 3, the double-wall spacer 3', and the fixing element 20 are firmly embedded in the initial shell 2a in the area of ​​the sleeve 23.

[0029] In this way, a Figure 3b Semi-finished product 9 (intermediate product) shown for the production of the concrete double-wall element 1 of the Figure 1created. The semi-finished product 9 comprises the hardened first shell 2a with the composite elements 3 embedded in sections, whose domes 4 protrude from the concrete layer 2a in the connection direction 14, the double wall spacers 3' and the sleeve 23 of the fixing element 20 embedded in sections.

[0030] Parallel to or following the production of the semi-finished product 9, formwork elements 6b are attached to a second pallet 5b. These formwork elements also correspond to the outer and inner contours of the concrete double-wall element 1 to be produced, but are arranged in reverse to the formwork 6a of the first pallet 5a. Furthermore, the anchor element 30 is attached to the base 25 of the fixing element 20 (see Figure 2a ) and connected to it (see Figure 2bThe foot 25 of the fixing element 20 is first inserted into a recess 33 provided for this purpose in the housing 31 of the anchor element 30 and pre-fixed there by a magnet 32 ​​mounted in the anchor element 30. For subsequent displacement-proof fixing of the foot 25, the anchor element 30 includes a locking slide 34, which moves in a locking direction 38 (i.e., in a direction perpendicular to the drawing plane). Figures 2a, 2b ) is movably mounted relative to the housing 31 of the anchor element 30. The longitudinal guidance of the locking slide 34 relative to the housing 31 of the anchor element 30 is effected by a projection 36 in the housing 31 of the anchor element 30, which engages in a groove or slot 35 of the locking slide 34 and thus effects a guided movement without unintentional release of the locking slide 34 (see Figure 2cThe groove or slot 35 runs at a slight angle; this results in the base 25 of the fixing device 20 being pressed against the anchor element 30 during a translational movement of the locking slide 34 in the closing direction 38 and thus being locked in the anchor element 30. The mechanical locking of the fixing element 20 relative to the anchor element 30 beyond the magnetic attraction force is thus achieved by a displacement of the locking slide 34 along the closing direction 38, so that – due to a trapezoidal opening 37 in the locking slide 34 and the opposite hemispherical shape of the base 25 of the fixing element 20 – the base 25 is clamped in the anchor element 30.

[0031] Liquid concrete 10b is now poured into the interior space 7b formed by the formwork elements 6b on the second pallet 5b, and the hardened first shell 2a located on the first pallet 5a is turned 180° using a turning device (not shown in the figures) so that the domes 4 of the shear connectors 3 point downwards (see Figure 3c The first shell 2a, with the fixing element 20 held within it and the anchor element 30 attached to the fixing element 20, is then placed precisely in a pre-calculated manner onto the liquid concrete layer 10b of the second pallet 5b. The domes 4 of the bonding elements 3 sink into the liquid concrete layer 10b (see 3D figure), and the anchor element 30 comes into contact with the surface of the second pallet 5b. Since the second pallet 5b (at least in the fastening area of ​​the anchor element 30) is made of a magnetizable material, usually steel, the anchor element 30 is magnetically attracted to the surface of the pallet 5b by means of the permanent magnet 32 ​​and is therefore firmly connected to the second pallet 5b by magnetic force. Since the fixing element 20 is embedded in the first concrete shell 2a in the area of ​​the sleeve 23 and the anchor element 30 is firmly attached to the second pallet 5b, the support device 40 thus fixes the first concrete shell 2a relative to the second pallet 5b.

[0032] The second pallet 5b, containing the liquid concrete layer 10b and the first shell 2b placed on it, is then moved to the curing station. Due to the first concrete shell 2b being fixed to the second pallet 5b by means of the support device 40, any displacement of the first concrete shell 2b relative to the second pallet 5b is prevented during this transport. In the curing station, the liquid concrete 10b poured into the interior 7b of the second pallet 5b is cured to form a second concrete shell 2b (second shell). The first shell 2a and second shell 2b are now firmly connected to each other; displacement of the two shells 2a and 2b relative to each other is prevented by the bonding elements 3 embedded on both sides. 3D figure ).

[0033] The locking slide 34 of the anchor element 30 is then released, allowing the fixing element 20 to be pulled out of the anchor element 30. The finished concrete double-wall element 1 is then removed from the second pallet 5b (arrow 41), with the anchor element 30 initially remaining on the second pallet 5b and being removed later (see figure). Figure 3e The fixing element 20 is then released from the sleeve 23 fixed in the first concrete shell 2a. The sleeve 23 remains in the concrete double-wall element 1.

[0034] The anchor element 30 and the fixing element 20 can be used to produce another concrete double-wall element after sliding a further sleeve 23 onto the first end section 21 of the fixing element 20. Reference symbol list

[0035] 1 Concrete double-wall element 2a, 2b First, second concrete shell 3 Bonding element 3' Double-wall spacer 4 Projecting areas of the bonding element 5a, 5b Pallet 6a, 6b Formwork 7a, 7b Interior of the formwork 8 Transport roller 9 Semi-finished product 10a, 10b Liquid concrete 11 Area near the edge of the first concrete shell 12a Edge of the concrete shell 13a Inside of the concrete shell 14 Connection direction 15 Cavity of the concrete double-wall element 20 Fixing element 21 First end section of the fixing element 22 Second end section of the fixing element 23 Sleeve 24 Ribs 25 Base of the fixing element 26 Outside of sleeve 26' Opening of the sleeve 27 Support area 28 Permanent magnet in the support area 29 Bent metal rod 30 Anchor element 31 Housing anchor element 32 Magnet 33 Recess in housing - receptacle for fixing element 34 Locking slide 35 Slot or groove in locking slide 36 Extension on the housing 37 Trapezoidal recess in locking slide 38 Closing direction 40 Support device 41 Removal direction

Claims

1. Support device (40) for the positionally accurate relative positioning of two concrete shells (2a, 2b) in the course of the production of a concrete double-wall element (1), wherein the support device (40) comprises - a fixing element (20) having a first end portion (21) for partially embedding in the first concrete shell (2a), - and an anchor element (30) for directly or indirectly fastening the support device (20) to a pallet (5b) carrying the second concrete shell (2b), characterized in that the fixing element (20) has a sleeve (23) which is releasably fastened to the end portion (21) of the fixing element (20).

2. Support device (40) according to Claim 1, characterized in that the sleeve (23) at least partially consists of a plastic.

3. Support device (40) according to Claim 1 or 2, characterized in that an outer side (26) of the sleeve (23) is provided with ribs (24).

4. Support device (40) according to one of the preceding claims, characterized in that the fixing element (20) comprises a supporting region (27) for directly or indirectly supporting the fixing element (20) on a pallet (5a) carrying the first concrete shell (2a).

5. Support device (40) according to Claim 4, characterized in that the fixing element (20) has, in the supporting region (27), a permanent magnet (28) by means of which the fixing element (20) can be fixed directly or indirectly to a pallet (5a) carrying the first concrete shell (2a).

6. Support device (40) according to one of the preceding claims, characterized in that the fixing element (20) has a foot part (25) for releasable fastening to the anchor element (30).

7. Support device (40) according to Claim 6, characterized in that the fixing element (20) can be connected to the anchor element (30) by means of a latchable plug-in connection.

8. Support device (40) according to one of the preceding claims, characterized in that the anchor element (30) comprises a permanent magnet (32) by means of which the anchor element (30) can be fixed directly or indirectly to the pallet (5b) carrying the second concrete shell (2b).

9. Concrete double-wall element (1) having two cured, planar concrete shells (2a, 2b) and connecting means (3) which are partially embedded in the concrete shells (2a, 2b) and serve both for connection and as spacers of the concrete shells (2a, 2b), wherein the first concrete shell (2a) comprises a sleeve (23), which is at least partially embedded in this concrete shell (2), for receiving a fixing element (20), characterized in that the sleeve (23) - is closed on one side, - is embedded in a region (11a) of this concrete shell (2a) that is close to the edge, - projects obliquely from the inner side (13a) of the first concrete shell (2a) that faces the second concrete shell (2b), - and has an opening (26') which faces the edge (12a) of the first concrete shell (2a).

10. Concrete double-wall element (1) according to Claim 9, characterized in that the sleeve (23) at least partially consists of a plastic.

11. Concrete double-wall element (1) according to either of Claims 9 and 10, characterized in that an outer side (26) of the sleeve (23) is provided with ribs (24).

12. Semi-finished product (9) for the production of a concrete double-wall element (1) according to one of Claims 9 to 11, wherein the semi-finished product (9) comprises a cured, planar concrete shell (2a) and connecting means (3) partially embedded in this concrete shell (2a), wherein protuberances (4) of these connecting means (3) project in a connecting direction (14) from an inner side (13a) of the concrete shell (2a), and wherein the semi-finished product (9) comprises a sleeve (23), which is at least partially embedded in the concrete shell (2a), for receiving a first end portion (21) of a fixing element (20) for a support device (40), characterized in that the sleeve (23) - is closed on one side, - is embedded in a region (11a) of this concrete shell (2a) that is close to the edge, - projects obliquely from the inner side (13a) of the concrete shell (2a), - and has an opening (26') which faces the edge (12a) of the concrete shell (2a).

13. Semi-finished product (9) according to Claim 12, characterized in that the sleeve (23) at least partially consists of a plastic.

14. Semi-finished product (9) according to either of Claims 12 and 13, characterized in that an outer side (26) of the sleeve (23) is provided with ribs (24).