EP0299353B1 - Method of making form elements for construction with permanent forms and elements made by same - Google Patents

Abstract

In one of the methods, connecting elements made by using concrete are produced by first pouring a fluid mortar, on the inside of a wall (1), into openings (5) of a template (2), with the addition of an adhesion promoter. A bell- or disc-shaped casting mould, which is filled with earth-moist concrete and is centred by the openings, is then placed upon this fluid mortar. The form elements thus produced can be stacked for hardening, with the interposition of thin plates, and subsequently joined to form form-element halves, for example by adhesive bonding. Modified methods produce the form elements by using dumbbell-shaped connecting elements made with the aid of axially separated mould halves. Form elements produced according to the method permit numerous modifications. <IMAGE>

Description

The invention relates to a method for the production of formwork elements for the shell concrete construction according to the preamble of claim 1.

Large-format formwork elements made of rigid foam are used for the shell-concrete construction, which are provided with grooves and tongues on their edges for mutual securing and have internal connection elements between the side walls to absorb the forces that occur when pouring concrete. Such formwork elements are known, for example, from DE-AS 26 18 125 and DE-OS 34 05 736. As connecting elements, dumbbell-shaped elements made of concrete with two opposing flanges and an intermediate piece are used in a known manner, which have grooves and tongues can be inserted into the corresponding grooves and tongues on the inside of the formwork element walls on the free flange surface. When pouring the formwork elements with concrete, the connecting elements combine homogeneously with the filled concrete. Unlike metal fasteners, there are no thermal bridges. Compared to connecting elements made of rigid foam, which are, for example, formed in one piece with the walls, fire penetration and sound bridges in the area of the connecting elements are avoided. In addition, the relatively heavy connecting elements made of concrete or similar material prevent the formwork elements from floating, so to speak, when filling in lightweight concrete. The contact pressure of the stacked formwork elements, achieved by the weight of the connecting elements, seals the joints so that the cement milk, which is important for setting, cannot run out. The weight of the connecting elements also ensures high stability, for example during a storm.

The known dumbbell-shaped connecting elements made of concrete are cast in one piece separately from the rigid foam formwork elements and then later inserted into the inner grooves of the formwork element walls in the factory or at the construction site, or also latched or glued. It is also known to manufacture the dumbbell-shaped connecting elements by separate casting of two halves, which are then later connected via intermediate pieces in the form of eyelets, hooks, rods, wires or screws (DE-OS 36 01 878).

Formwork elements of the type described above have proven themselves. However, their production is relatively complex and requires a lot of space and time because of the hardening time for the concrete parts of the connecting elements.

The invention has for its object to provide a method for the production of formwork elements for the sheath concrete construction according to the preamble of claim 1, which reduces the manufacturing costs and also leads to a better, more resilient and cheaper formwork element. The solution to the problem is specified in claim 1. Developments of the method and formwork and connecting elements produced by the method are the subject of the dependent claims.

If the connecting elements are cast directly on the walls of the formwork elements, there is no separate production. The use of the flow mortar with an adhesive promotes an extraordinarily good, permanent and tensile connection with the walls of the formwork element. The coupling agent can be added to the flowing mortar in a simple manner. However, there is also the possibility of applying the adhesion promoter to the walls at least in the area of the stencil openings, for example by spraying or painting in the form of a coating. Finally, the adhesion promoter can be applied by immersing the walls in a bath.

In a particularly advantageous manner, the addition of a color can simultaneously ensure that the otherwise snow-white exterior is covered by the color, in particular in the case of rigid foam. The bright white appearance is particularly annoying in sunshine and leads to complaints similar to the well-known snow blindness. The casting of the flanges from concrete or a similar material is considerably simplified because the concrete can be poured into the relatively large opening from above, which defines the subsequent connection surface of the connecting element to its associated wall. The forms are reusable and the stencils ensure very good dimensional accuracy and reproducibility of the formwork elements. In a further development of the invention, it is possible to stack the freshly manufactured walls on top of one another for curing the concrete and for storage, so that the space required for production and storage is significantly reduced. For this purpose, the manufactured walls with their flanges facing upwards are laid out in one layer on a flat surface, then an intermediate layer of thin panels, for example plywood panels, is placed on the flanges and then another layer of walls is placed on the panels. In this way, stacks with a height of several meters can be formed. After laying out a layer, the concrete of the connecting elements at the beginning of the layer has solidified to such an extent that no deformation of the connecting elements occurs when the next layer is placed on the thin plates. The layers of walls lined up in each case must have a certain length so that sufficient time passes before the next layer is placed on top. Before the walls are stacked, the free ends of the flanges are expediently set to a predetermined height by pulling them off or slightly pushing them in using a template which is, for example, bridge-shaped. The later formwork elements then have very precise external and internal dimensions.

A particular advantage of the formwork elements produced by the method according to the invention is that smooth walls cut from a block of preferably rigid foam can be used without grooves or other notches or recesses. The use of expensive injection molds is eliminated. Such formwork elements are therefore very cheap and can be placed in a bandage, such as hollow blocks. The relatively high dead weight of the concrete connecting elements ensures sufficient stability even of storey-high walls, which can then be filled with normal or lightweight concrete. Likewise, the weight of the concrete connecting elements prevents the formwork elements from floating when pouring lightweight concrete. If additional protection against the effects of wind or storm is to be achieved, the stacked formwork elements can be connected to each other by gluing before the filling with concrete takes place.

In the development of the invention, there are many possibilities for the formation of the connecting elements produced by the method according to claim 1 and its dependent claims. The flanges are preferably circular, but can also be oval, rectangular or square. The molds into which the concrete is poured can be bell-shaped in such a way that a shaft connects to the flange. To connect two walls to formwork elements, the free ends of the shafts are then glued together to form the intermediate piece. With the help of a simple device it can be ensured that the ends of the shafts meet exactly. Before curing, at least one groove-shaped indentation can be provided at the transition between the flange and the shaft as a later bearing point for a mounting bar, for example by pressing in such a mounting bar.

The shape for producing the flanges can also be designed so that a disk-shaped flange is formed. This is provided with a central, preferably circular cylindrical depression, and for Connecting two walls to formwork elements, you then glue shaft-shaped spacers between the floors of two opposing depressions. By changing the length of the shaft-shaped intermediate pieces, the internal dimensions of the formwork elements and thus the thickness of the later wall can be adjusted. The shaft-shaped intermediate piece can expediently be made of concrete by means of a cylindrical hollow mold. Before curing, grooved impressions can also be made in the area of the two ends as a later bearing point for mounting rods.

Another further development provides that in order to form the intermediate piece, further fastening means, such as mounting rods, hooks, eyes, screws, wires, sheet metal strips and the like, are embedded in the flange or in the subsequent shaft before curing. In the same way, bores can also be pressed in for the later attachment of further fastening means, for example with the aid of dowels.

A grid dimension is predefined by the uniform spacing of the connecting elements of, for example, 25 cm achieved with the templates. At the construction site, the formwork elements between the connecting elements can then be sawn apart in a grid dimension; but this is not easy in the area of the connecting bridges. In a further development of the invention, this limitation is overcome by inserting central separating plates into the molds for producing the flanges and, if appropriate, the shaft-shaped intermediate pieces, which run through the axis of the connecting elements and in the direction of the height of the formwork elements. The finished formwork element can then be cut off parallel to and in the extension of the dividing plates, so that work can then also be carried out in half the grid dimension. Since separation is usually only necessary in the area of the ends of the formwork elements, the separating plates are expediently used only in the flanges or shaft-shaped intermediate pieces adjacent to the two ends of the walls.

Another solution of the method according to the preamble of claim 1 is characterized in claim 16. The dumbbell-shaped connecting elements are thus produced with the help of half molds, the inner contour of which corresponds to half of an axially cut connecting element. After the two mold halves have been filled with concrete, the mold halves can either be placed on top of one another immediately, so that the concrete fillings firmly bond to one another. However, a release agent, for example a film, can also be inserted, so that connecting element halves are produced. These can either be used separately, placed next to each other or glued together to produce the formwork elements. Filling with concrete can be done manually or mechanically by pouring, pouring, pressing or shaking. Depending on the method used, the concrete is expediently earthy to liquid.

An additional solution for the method according to the preamble of claim 1 is given in claim 19. Here again two axially divided mold halves of the type described above are used, which, however, are placed flush against one another before filling to form a mold and are firmly connected to one another, for example by clips. In addition, the connection at the edges can be improved by tongue and groove formation. The filling with concrete can again be done by pouring, shaking or pressing in from above and below.

In the manufacturing processes for the connecting elements described above, reinforcement wires can be introduced into the mold or a mold half in an approximately axial position. This results in a significant increase in tensile strength, particularly when the wires are profiled and have swaged or welded thickened ends or are only bent. Even if the connecting elements then break during transport, for example, the tensile connection between the walls of the formwork element is retained.

Fig. 1

schematisch die Herstellung der Wand eines Schalungselements nach dem erfindungsgemäßen Verfahren nach Anspruch 1;

Fig. 2

schematisch die einzelnen Schritte des Verfahrens gemäß Fig. 1;

Fig. 3

das Aufeinanderstapeln von Schalungselementwänden, die nach dem Verfahren gemäß Fig. 1 und 2 hergestellt worden sind;

Fig. 4

die Seitenansicht eines Ausführungsbeispiels für ein Schalungselement nach der Erfindung;

Fig. 5

die Seitenansicht eines weiteren Ausführungsbeispiels für ein Schalungselement nach der Erfindung;

Fig. 6

im Querschnitt eine geteilte Gießform für den Flansch eines Verbindungselements nach dem erfindungsgemäßen Verfahren gemäß Anspruch 1;

Fig. 7

schematisch die Möglichkeit einer Auftrennung eines Schalungselements im halben Rastermaß;

Fig. 8

die Seitenansicht eines weiteren Ausführungsbeispiels für ein Schalungselement nach der Erfindung;

Fig. 9

die Seitenansicht für ein Ausführungsbeispiel eines Schalungselements nach der Erfindung;

Fig. 10

eine Eckverbindung mit kontinuierlichem Betonanschluß;

Fig. 11

einen Wandanschluß mit kontinuierlicher Betonverbindung.

The invention is described below using exemplary embodiments in conjunction with the drawings. Show it:

Fig. 1

schematically the manufacture of the wall of a formwork element according to the inventive method according to claim 1;

Fig. 2

schematically the individual steps of the method according to FIG. 1;

Fig. 3

the stacking of formwork element walls which have been produced by the method according to FIGS. 1 and 2;

Fig. 4

the side view of an embodiment of a formwork element according to the invention;

Fig. 5

the side view of another embodiment for a formwork element according to the invention;

Fig. 6

in cross-section a split mold for the flange of a connecting element according to the inventive method according to claim 1;

Fig. 7

schematically the possibility of separating a formwork element in half the grid dimension;

Fig. 8

the side view of another embodiment for a formwork element according to the invention;

Fig. 9

the side view of an embodiment of a formwork element according to the invention;

Fig. 10

a corner connection with continuous concrete connection;

Fig. 11

a wall connection with continuous concrete connection.

1 and 2 illustrate the method according to the invention with its individual steps. A template 2 made of, for example, plastic or sheet metal is placed on a wall 1 of a formwork element formed from two such walls, centering pins 3 ensuring a precisely defined position of both parts on, for example, a work table. The plate 1 consists for example of rigid foam. 1, the plate 1 according to FIG. 2 has grooves 4 with a dovetail cross section which, however - as explained above - can only be present in addition.

The template 2 is provided with circular recesses 5 which have a uniform spacing from one another which determines the grid dimension. However, they can also have a different shape, have an irregular spacing and be arranged off-center. After placing the template 2 on the wall 1, the cross-sectional image according to FIG. 2a results in the area of an opening. Then you pour a flow mortar 6 provided with an adhesion promoter into the openings 5 and pull the mortar off smoothly. The adhesion promoter can also be applied to the wall as a coating, for example by dipping, and optionally colored.

2b and the two openings 5 on the right in FIG.

Subsequently or parallel to this process step, a casting mold 7 with approximately the shape of a bell is filled with earth-moist concrete 8. The shape has its large opening upwards (reverse position as in Fig. 2d), so that the concrete 8 can be filled easily.

Then you put the form 7 with the still moist concrete 8 on the flowing mortar 6, the edge of the form 7 being received by the openings 5, so that an exact centering is given, cf. Fig. 2c. The molds 7 can then be removed, if necessary with gentle shaking, and the template 2 can also be removed later (see FIG. 2d).

The walls 1 with the molded-on connecting element halves 10, which consist of the concrete 8 and the flowing mortar 6, are - as shown schematically in FIG. 3 - side by side on a flat surface, for example the concrete floor of a hall, in a length between 10 and 30 m or lined up more. When a layer is finished, lay to protect the fresh connecting element halves 10 thin plywood panels 11 or panels made of another material with dimensions of 100 x 200 x 0.3 cm, for example. The next layer of connecting element halves 10 can then be put on. In this way, stacks with a total height of 2 to 3 m can be placed. Sufficient time must only pass so that the concrete 8 of the connecting element halves 10 becomes so strong that sufficient loads can be carried.

Fig. 4 shows schematically how two walls 1 with connecting element halves 10 are later joined together by gluing on the end face to formwork elements. By using a simple device (not shown) it is ensured that the end faces of the connecting element halves 10 meet exactly. The dumbbell-shaped connecting elements 20 formed from two halves 10, each with two flanges 12 and a connecting intermediate piece 13, which in the present case has the shape of a shaft, are formed.

5, a shape (not shown) was used in the manufacture of the connecting element halves, which, in contrast to the shape 7 according to FIG. 2d, has the shape of a flat bowl, so that only flanges 22 are formed which have a central inner own kung 14. When joining two walls 1 with flanges 22, shaft-shaped intermediate pieces 23 are then glued into the depressions 14. In both exemplary embodiments according to FIGS. 4 and 5, the intermediate pieces 13 and 23 in the area of their transition into the flanges 12 and 22 have been provided with grooved indentations 15 before hardening, which serve as a bearing point for mounting rods (not shown).

FIG. 6 shows a casting mold 17, which essentially corresponds to the casting mold 7 according to FIG. 2d, but additionally has a central partition plate 16. The one with this shape The connecting element halves produced have the same shape as the halves 10, but are separated into two parts, so that a formwork element can later be separated at this point by sawing, as the dashed line 18 in FIG. 7 shows schematically. In addition to a separation between the connecting elements 20 in the area of the dashed line 19 and the resulting grid dimension of, for example, 25 cm, half a grid dimension can thus be separated, making it easy to adapt to the particular circumstances on a construction site.

Fig. 8 shows a further embodiment for a formwork element according to the invention. Again, flanges 22 according to FIG. 5 have been cast onto the walls 1 with a central depression 14. Before hardening, wires 24 have additionally been anchored in the flanges 22. A tubular intermediate piece 33, which can also consist of concrete, is used to join two walls 1 with flanges 22. The wires 24 are guided from both sides through the tubular intermediate piece 33, pulled outwards and then twisted together under tension. Recesses 25 on the edge of the intermediate pieces 33 enable the wires 24 to be guided out without interference.

9, sheet metal strips 26 have been anchored in the flanges 22. The connection of two walls 1 with flanges 22 then takes place via the metal strips 26, screws or wires being passed through bores 27, for example, or a connection being made by spot welding. An increase in the distance and thus the clear width of the formwork element can be achieved by an extension piece 28, which also has bores 27.

10 schematically shows the execution of a corner connection, the first layer and subsequent, odd-numbered layers in the left part a and the second layer and subsequent, even-numbered layers in the right part b Layers of formwork elements are shown. 10a, the inner wall 1 has been provided in the region of the left intermediate piece 20 with a cutout 29 which leads to the bottom of the flange 12. In the subsequent filling with concrete, there is a connection of the filled in-situ concrete to the flange 12 and overall a continuous concrete wall running continuously over the corner, which has no interruption through a hard foam layer of the walls 1 and can therefore constitute a firewall. The same applies to the next layer according to FIG. 10b, in which a cutout 29 also enables a continuous concrete connection.

11 shows a wall connection with alternating layers according to FIGS. 11a and 11b. Here, too, cutouts 29 ensure continuous concrete walls. Such a continuous concrete core not only avoids fire penetration and sound bridges, but is also more statically loadable.

Fig. 10a also shows an end piece 30 which is glued between the walls 1 and closes the formwork element to the outside.

The mold halves described above can be made from metal, for example sheet steel, but also from plastic.

Claims (20)

1. A method of manufacturing formwork elements for the haunching concrete construction method with walls (1) and connecting elements (20) of concrete or similar construction materials for the walls, the connecting elements (20) being dumbbell-shaped with two flanges (12) secured to mutually opposite walls (1) and an intermediate member (13, 23, 33),
   characterised by the method steps:

   a) on the interior of a wall (1) there is laid a template (2) having openings (5) corresponding to the shape of the flanges (12);

   b) a fluid mortar (6) is poured into the openings (5) and screeded smooth, a coupling agent appropriate to the material of the wall (1) ensuring connection of the mortar to the wall;

   c) moulds (7) corresponding to the design of the flanges (12), with their flange openings facing upwards, are filled with earth-moist concrete (8) and screeded;

   d) the moulds (7) are inverted with their flange openings facing the mortar (6) and into the template openings (5);

   e) the moulds (7) and templates (2) are removed for re-use; and

   f) after setting, two rolls (1) at a time are connected by means of the intermediate members (13, 23, 33).
2. A method as claimed in claim 1,
   characterised in that the coupling agent is mixed with the mortar (6).
3. A method as claimed in claim 1,
   characterised in that the coupling agent is applied to the walls (1) as a coating at least in the vicinity of the template openings (5).
4. A method as claimed in claim 3,
   characterised in that the coupling agent is applied by dipping the walls (1).
5. A method as claimed in claim 4,
   characterised in that the coupling agent is tinted.
6. A method as claimed in any of claims 1 to 5,
   characterised by the method steps:

   g) before step f), finished walls (1) are laid in a layer on a flat surface with their flanges (12, 22) pointing upwards;

   h) an intermediate layer of thin sheets (11) is laid on the flanges (12, 22);

   i) a further layer of walls (1) is laid on the sheets (11); and

   k) steps h) and i) are repeated.
7. A method as claimed in any of claims 1 to 6,
   characterised in that after removal of the moulds (7) in step e) the free ends of the flanges (12) are adjusted to a preset height by means of a template.
8. A method as claimed in any of claims 1 to 7,
   characterised in that the moulds (7) have a bell shape such that the flange (12) adjoins a stem (13), and to connect two walls (1) in step (f) the free ends of the stems (13) are bonded together to form the intermediate member.
9. A method as claimed in claim 8,
   characterised in that before setting at least one groove-like indentation (15) is made at the transition between the flange (12) and stem (13) to act subsequently as a bearing for a reinforcing rod.
10. A method as claimed in any of claims 1 to 7,
    characterised in that the moulds are so designed as to produce a disc-like flange (22), the flange is provided with a central, preferably right-cylindrical depression (14), and to connect two walls (1) in step (f) stem-like intermediate members (23) are bonded to the bottoms of the depressions (14).
11. A method as claimed in claim 10,
    characterised in that the stem-like intermediate member (23) is made from concrete by means of a cylindrical hollow mould, and before setting it is provided near both its ends with groove-like indentations (15) to act later as bearings for reinforcing rods.
12. A method as claimed in any of claims 1 to 9,
    characterised in that to form the intermediate member continuing fixing means such as reinforcing rods, hooks, eyes, screws, wires (24), metal strips (26) or the like are embedded in the flange (22) or in the adjoining stem before setting.
13. A method as claimed in claim 12,
    characterised in that bores for mounting the continuing fixing means are impressed in the flange (22) or the adjoining stem before setting.
14. A method as claimed in any of claims 1 to 11,
    characterised in that central separating sheets (16) are laid in the moulds (17) for manufacturing the flanges (12) and possibly the stem-like intermediate members, these sheets (16) extending through the axis of the connecting elements (20) and in the direction of the height of the formwork element, so that the finished formwork element can be cut off parallel to, and in the extension of, the sheets (16).
15. A method as claimed in claim 14,
    characterised in that the separating sheets (16) are used only for the flanges or stem-like intermediate members adjoining the two ends of the walls (1).
16. A method as claimed in the generic clause of claim 1,
    characterised by the method steps:

    m) mould halves of which the internal contour corresponds to half of an axially cut, dumbbellshaped connecting element are filled with concrete and screeded along the cutting plane;

    n) two mould halves at a time are laid with their cutting planes on top of one another;

    o) after at least partial setting the mould halves are removed; and

    p) the connecting elements are bonded to two mutually opposite walls using a coupling agent.
17. A method as claimed in claim 18,
    characterised in that before step n) separating means are introduced between the two mould halves.
18. A method as claimed in claim 16,
    characterised in that before step n) a reinforcing wire is laid in one of the mould halves along the axis of the connecting element.
19. A method as claimed in the generic clause of claim 1,
    characterised by the method steps:

    q) two mould halves of which the internal contour corresponds to half of an axially cut, dumbbellshaped connecting element are laid and aligned on one another along the cutting plane and rigidly connected together to form a mould;

    r) the mould is placed on a flat surface with its axis running vertical and is filled with concrete;

    s) after at least partial setting the mould halves are removed; and

    t) the connecting elements are bonded to two mutually opposite walls using a coupling agent.
20. A method as claimed in claim 19,
    characterised in that before step s) a reinforcing wire is introduced into the mould along the axis of the connecting element.

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