EP0832335B1 - Concrete shuttering panel - Google Patents

Abstract

To give a lightweight lost concrete shuttering panel (1) adequate strength it is proposed to lay threads (5, 6), especially glass fibres, in criss-cross array in the region of the shuttering panel subject to tensile stress in use. In order to increase the strength of the shuttering panel further, fibres may be also be laid in the regions subject to compressive stress. It is proposed that glass fibres be used as they have the advantage of higher tensile strength for a given weight and are resistant to corrosion in the concrete. The side (9) of the shuttering panel facing the in-situ concrete (18) is to form an intimate bond therewith and is chamfered at its edges (13).

Description

The invention relates to a thin, manually transportable and Layable formwork panel made of concrete for a reinforced concrete component.

Under a lost formwork here is a formwork for one understood on site in cast concrete, the after setting the concrete is not removed, but with the Structure remains connected - be it that it lies in the ground and cannot be removed, be it as a load bearing or shaping part of the building is used.

A lost formwork panel is known (EP 0 110 874 B1), where a flat or spatial reinforcement steel mesh between two prefabricated, correspond to the reinforcing steel mesh grooved Panels embedded and this ensemble to concrete is cast in a monolithic supporting structure. The procedure to produce this formwork panel is very complex and therefore the plate is expensive. Because reinforcement steel according to regulations the plate must be covered by at least 2 cm of concrete inevitably so thick that it changes the dimensions and closes is difficult than being handled by a single person, for example can be.

Other common lost (sub) formwork panels for so-called Slab ceilings with concrete consist of the for the statics of the Required spatial reinforcement from steel bars, the only in their lower, when installed, stressed train Area is cast in concrete. After installation, too the upper area of the reinforcement is cast with in-situ concrete and so that the ceiling is created. Because the reinforcement for every building is calculated statically individually, formwork panels for such slab ceilings are made to order. This not only makes their production more expensive, it also complicates them Disposition during manufacture, storage, transport and on the construction site.

It is also a concrete formwork that can be used as a building element known (DE 1 705 248 U), but which has no reinforcement. Around sufficient strength not only when handling, but also to ensure when pouring with in-situ concrete, such a Formwork panel, however, so thick and therefore so heavy that it would no longer be manageable manually.

Another known lost formwork panel (DE 25 21 577 A1) has knobs on its surface facing the in-situ concrete which is supported by steel reinforcement and therefore in the Corrosion-preventing distance from that facing away from the in-situ concrete Surface of the formwork panel is held. A formwork panel with such But pimples are more difficult to manufacture and also more difficult as a formwork panel consisting of a flat plate: the Nubs do not contribute to them only due to the panel thickness between the knobs have certain strength, but contribute to their weight.

The object of the invention was therefore to create a lost one Formwork panel to create the applicable building standards and rules the standard part taking into account the architecture in large quantities Manufactured cheaply, stocked and for all applications is equally applicable. It solves this task through Features of the main claim.

The fact that the formwork panel consists of a flat plate achieves the advantage that it is easy to manufacture and that their material volume and thus their weight is not greater than the panel thickness required for the strength of the formwork panel necessary is.

The reinforcement of the formwork panel according to the invention is not that the structure of the structure causing steel reinforcement, but one reinforcement that only brings about the strength of the formwork panel. The Reinforcement of the formwork panel according to the invention is not that the structure of the structure causing steel reinforcement, but one the strength of the reinforcement only for the formwork panel. The the structure's structural reinforcement is above and thus installed independently of the formwork panel according to the invention. With this, the formwork panel is reinforced by the structure independent and can be used universally in all structures become.

There are already boards, preferably made of plaster, for production a lost formwork known (DE-GM 77 14 361), the or embedded on both sides in the surfaces of the plates Have inlays made of a fabric or a fleece. This Inlays protrude from the panel on the narrow sides, around the Bond effect between the plates and the one to be inserted To increase core concrete. While it is mentioned that these deposits are the Increase the tensile strength of the plates. A fleece, but also a However, any type of tissue cannot be combined with plaster Formwork panel achieve the sufficient strength for formwork of steel-reinforced ceilings to be created in cast concrete. Accordingly, the panels are only used to form walls proposed. In addition, the material-related chemical properties of gypsum on the one hand and steel reinforcement on the other hand to the steel processes that corrode steel, not only does the reinforcing steel lose its strength, but also the structure of the building is impaired.

The formwork panel according to the invention is therefore made of concrete and has a type of reinforcement that is in connection with the concrete the required strength when the plate is thin gives. The reinforcement in the lower, in the horizontal installation state the area subjected to tension has the necessary work processes connected traffic load plus the load of the applied in-situ concrete. Another, in the one provided Installation condition under pressure, upper area of the Formwork panel inserted reinforcement serves the formwork panel to make it shatterproof when handling. This reinforcement can therefore be weaker than that in the area under tension.

In accordance with the invention, intersecting shares serve as reinforcement parallel, one-dimensional body like (monofilament) wires or (multifile) threads made of corrosion-resistant material high Tensile strength and low elongation. Meet these conditions especially wires or threads made of inorganic substances such as Glass. With particularly high demands on strength and low Weight can be justified by the use of carbon fibers be.

• daß es infolge seiner im wesentlichen mineralischen Bestandteile ein dem Beton sehr ähnliches Material ist, das sich daher auch sehr innig mit dem Beton verbindet, auf Temperaturänderungen ähnlich reagiert wie Beton usw.;
• daß es eine sehr hohe Zugfestigkeit besitzt, die bereits mit geringer Masse und damit Gewicht eine hohe Festigkeit bewirkt;
• daß es einen E-Modul ähnlich demjenigen von Beton aufweist und daher im Belastungsfall sich ähnlich verhält wie Beton;
• daß Fäden und Gewebe aus Glasfasern ein handelsübliches und damit ohne weiteres verfügbares und wohlfeiles Halbzeug sind.

For the present application, glass has the advantages

• that due to its essentially mineral components it is a material very similar to concrete, which therefore also binds very intimately to the concrete, reacts to temperature changes in a similar way to concrete, etc .;
• that it has a very high tensile strength, which results in high strength even with low mass and thus weight;
• that it has a modulus of elasticity similar to that of concrete and therefore behaves similarly to concrete when loaded;
• that threads and fabrics made of glass fibers are a commercially available and therefore readily available and inexpensive semi-finished product.

According to the invention, the formwork panel is reinforced at least two, then preferably at an angle of Crossing 90 ° and parallel to the sides of the formwork panel trending sheets of thread. If formwork panels in other than mutually perpendicular directions are most heavily loaded or if the formwork panels are not rectangular (e.g. equilateral triangular in buildings with a floor plan in a 60 ° grid) the thread coulters can also be used in others Cross angles. However, the thread sheets preferably run in Direction of the heaviest strain on the train.

For higher demands on the strength of the formwork panel or when the formwork panel is loaded in several directions can also use more than two, for example three sets of threads be, which are then advantageously at angles of approximately 60 ° cross.

The individual threads of the thread sheets have a mutual one Distance that the passage of liquid concrete through by the crossing stitches formed stitches allowed. Each after the grain of the concrete used, this distance can be from a few mm up to about 15 mm.

The strength of the reinforcements can be selected according to the strength requirements by choosing both the thread thickness and the mutual spacing of the threads in the thread sheets. It has been shown that the required strength of the formwork panel according to the invention can be achieved with a reinforcement in the form of a textile fabric (fabric or cross-linked sheets) with a weight per unit area of about 100 g / m ² . In some cases, for example with other plate dimensions or other load values, higher or lower m ² weights can also be advantageous. Different or the same basis weights can be achieved with threads of different fineness and / or different spacing between the threads.

As a rule, the upper reinforcement can be chosen weaker than the lower reinforcement, its basis weight, i.e. the concentration and / or the strength of their threads may be less than that in the thread sheets of the reinforcement in the lower area.

The crossing thread sheets can be independent of each other be. For the sake of easier, in particular joint handling however, they are connected or networked and form a two-dimensional, flat structure. There the tensile stress, however, only ever from the individual threads is included, the links of the reinforcement are one-dimensional to address. The threads can be crosslinked by gluing, Welding or enveloping coating can be achieved. Preferably are the thread cords as a warp and a weft with each other interwoven, but for the purpose of the sliding resistance of the very light (with a large mutual distance between the threads) Fabric also a coating, welding or gluing is advantageous.

By using the thin thread coulters as reinforcement, the Thickness of the formwork panel according to the invention kept so small be that the overall height of a ceiling despite installing a steel reinforcement is not raised above the formwork panel. Preferably the lost formwork panel is just so thick that the prescribed one Concrete thickness below or above the steel reinforcement of 2 cm given is. This means that the steel reinforcement can be used directly without the otherwise required spacers, placed on the formwork panel become.

A steel reinforcement must be replaced by at least one 2 cm thick concrete layer must be covered. This is due to the minimum thickness the formwork panel ensures. So that condition is also met at the joints of the formwork panel provided the edges of the formwork panel on top of the in-situ concrete chamfer facing side. This ensures that the height the remaining butt joint between the formwork panel is reduced and that thin concrete glue seep into this butt joint can and it fills in and so the prescribed concrete thickness under or above the reinforcement.

Since the formwork panel and in-situ concrete are only on one level surface touch, it is provided, the formwork panel on the in-situ concrete facing side so that an intimate connection arises between the formwork panel and the in-situ concrete. This can be due to the rough surface design of the formwork panel can be achieved. This surface of the formwork panel can also be used have undercut recesses in a known manner, in which the in-situ concrete enters and anchors. Grooves in the Surface of the formwork panel have proven to be a means of reaching Proven connection between formwork panel and in-situ concrete.

The dimensions of the formwork panel can be chosen arbitrarily become. A standard size of 100 cm x 50 cm corresponds to the standard size usual formwork panels. In some cases, however dimensions deviating from this may be advantageous.

The intended thickness of the formwork panel of about 2 cm and one preferred length and width dimensions of 100 cm and 50 cm lead to a weight of the formwork panel of about 25 kg, the only one person can handle the formwork panel.

The intended thickness of the formwork panel of about 2 cm allows also easy cutting of the panels to partial dimensions stone-cutting release agents such as stone saws or cutting discs. It has been shown that a lower armouring is used for this purpose An incision is sufficient to make the formwork panel along the To be able to break incisions.

It is known that due to its alkalinity, glass is particularly liquid, concrete that has not yet set can be attacked. Around an impairment of the strength of the reinforcement in the formwork panel preventing this reaction continues proposed to use threads made of alkali-resistant glass fibers. Such threads are offered by specialist companies.

In a further embodiment of the invention it is proposed that Formwork panel on its side facing away from the in-situ concrete with a Insulation layer against heat / cold, against sound or other To provide actions. This has the advantage that such an insulation layer not in a separate operation must be attached to the building. Rather, you can already at Manufacture of formwork panels in a more economical way Way.

The formwork panel according to the invention is mainly for creating of cast, reinforced concrete ceilings. she can but also as lost formwork for walls, for beams, serve for recesses, for foundations etc.

Fig. 1

den Querschnitt durch eine Schalungstafel;

Fig. 2

das Schalen einer Decke unter Verwendung der Schalungstafel im Schnitt;

Fig. 3

das Schalen eines Unterzuges unter Verwendung der Schalungstafel im Schnitt;

Fig. 4

das Schalen eines Gebäudefundamentes mittels der Schalungstafel im Schnitt;

Fig. 5

das Schalen einer Aussparung mittels der Schalungstafel im Schnitt;

Fig. 6

eine mittels der Schalungstafeln erstellte Wand im Schnitt;

Fig. 7

eine Schalungstafel mit Dämmschicht im Schnitt.

In the figures of the drawing, two embodiments of the formwork panel according to the invention and several possible uses of the same are shown by way of example. Show it

Fig. 1

the cross section through a formwork panel;

Fig. 2

formwork of a ceiling using the formwork panel in section;

Fig. 3

the formwork of a beam using the formwork panel in section;

Fig. 4

Forming a building foundation using the formwork panel on average;

Fig. 5

the formwork of a recess by means of the formwork panel in section;

Fig. 6

a section of a wall created using the formwork panels;

Fig. 7

a formwork panel with an insulation layer on average.

As can be seen in particular from FIG. 1, there is the inventive Formwork panel 1 preferably made of a flat plate 2 made of concrete with a grain size not coarser than 8. In the case of horizontal installation on the stressed area of the formwork panel 1 close to the bottom 3, this plate contains one Reinforcement 4 in the form of an insert made of two intersecting Shares 5, 6, each with parallel threads. In the Embodiment to the left of the breaking line 7 form these thread groups 5, 6 a fabric 8, in the embodiment on the right of the break line the cords of thread lie one above the other. To move the To prevent threads in the manufacture of plate 2 are the threads at least of the thread coulters lying on top of each other on theirs Crossing points are connected to each other so that they cannot slide.

The top 9 of the plate 2 has a profile that in the embodiment left of the break line 7 as in cross section dovetail-shaped, longitudinal or transverse grooves 10, in the embodiment to the right of the break line as longitudinal or transverse running or crossing grooves 11 is formed. Below this profile 10, 11, the plate 2 contains another Reinforcement 12 also in the form of an insert from intersecting Shares 5, 6 with threads parallel to each other, also be interwoven or can only lie on top of each other.

The edges 13 of the plate 2 are against the top 9 in Art a chamfer 14 reaching about half the thickness of the plate beveled. The thickness of the plate 2 is preferably 2 cm.

To produce a ceiling 15 with formwork panels 1, these are 2 on a support structure indicated by dashed lines 16 with the narrowest possible gaps in that shown in FIG. 1 Designed up / down orientation. On this formwork sheet layer the steel reinforcement 17 becomes immediate, without spacers hung up. On this underlay, 18 the ceiling 15 are cast.

During this pouring, concrete flows into the bevels 14 Grooves 19 and low-viscosity concrete glue in the gaps between the edges 13 of the formwork panels 1. This is - starting of the thickness of the formwork panels 1 by 2 cm - ensures that the steel reinforcement 17 at all points by at least 2 cm Concrete is covered. After the concrete has set, only that Support structure 16 to be removed. A kick off from Formwork panels of concrete surfaces and plastering of pouring bars is unnecessary.

3 formwork panel strips 21 cut to size and fastened by means of the protrusion 22 indicated by dashed lines. After inserting the beam reinforcement 23 (and one here ceiling reinforcement, not shown), the ceiling 15 and Beam 20 cast. As can be seen, is also through here Influence of concrete in the chamfers 14 and of concrete glue in the subsequent columns the prescribed coverage of the Reinforcement 23 guaranteed by concrete.

Also for making a foundation strip 24 in the ground 4 lost formwork panel according to the invention can be used with advantage. This can be done on the outside of the foundation strip 24 formwork panel 1, for example a nail 25 or other suitable sprouting in excavated foundation trench. Even the inside of the foundation strip 24 can be by means of a formwork strip 26 be limited if they are not from the embankment of the excavated foundation trench should be limited.

In-situ concrete 18 can then be poured into the space thus defined. After it has set, the bottom nail 25 can be pulled, making the foundation without the need to remove one Formwork is completed.

5 shows, in reverse, the formwork of a beam according to FIG. 3 the formation of a recess 27 in a concrete cast 15 ceiling or wall. The space of the provided recess 27 is on all sides with appropriately cut strips 21 of formwork panels dressed, which are held by support members 16. The strips 21 of the formwork panels are chamfered 14 arranged so that by the inflow already described of in-situ concrete in the grooves formed by the chamfers or thin concrete glue in the remaining columns the concrete layer over a lying in the ceiling 15, not shown here Reinforcement is ensured.

One created using the formwork panels according to the invention Wall 28 is shown in FIG. 6. The formwork panels 1 are in Fix gutters 29 in the floor 31, for example by means of nails 30 Bottom rail 32 placed or in a corresponding cover rail 33 held. At the correspondingly drilled out areas of the butt joints the formwork panels 1 steel tie rods 34 are inserted, the as well as the bottom rail 32 and the top rail 33 the pressure of the filled, liquid in-situ concrete. The wall 28 also has steel reinforcement 17. A support structure for Holding the formwork until the in-situ concrete solidifies is here already removed.

A formwork panel provided with an insulation layer 35 is shown in Fig. 7 shown. It consists of the actual one Formwork panel 1 as shown and described in Fig. 1. On its underside 3, that is, the side facing away from the in-situ concrete to be applied Side is an insulation layer 35 against the passage of Heat, sound or other influences such as electromagnetic Radiation or fire arranged. The insulation layer 35 can also be used to absorb influences such as sound and be trained.

The insulation layer 35 consists of material known to the person skilled in the art, that has the intended insulation effect, e.g. from hard foam such as Styrodur, made of fiber material such as felt or rock wool Multi-layer panels, the combinations of these materials with Flat structures such as cardboard, foils or sheet metal can contain or from other. The insulation layer 35 is fixed to the actual one Formwork panel 1 connected, e.g. by means of (plastic) Nails 36 or by gluing.

The formwork panel 1 according to the invention can thereby be produced be that in a pan-like, flat shape first the lower reinforcement 4 is inserted. Then the shape with the the specified amount of concrete. Due to the large meshes in the Reinforcing mesh passes and envelops concrete through the mesh on the bottom. The upper reinforcement is placed on this concrete filling 12 placed and then closed the mold with a lid. In this cover is the chamfer 14 and the grooves 10 or Grooves 11 forming the shape incorporated - which the grooves 10 forming cores can be drawn in the longitudinal direction as rails be trained. The projections in the lid press the upper one Reinforcement 12 in the concrete. By applying heat to the mold the setting of the concrete can be accelerated. With a A variety of ladles can formwork panels in series getting produced.

According to another method, a quasi-endless formwork panel belt can be used continuously manufactured and individual plates after Setting of the concrete.

List of reference numbers

1

Formwork panel

2nd

plate

3rd

bottom

4th

lower reinforcement

5, 6

Cords

7

Fault line

8th

tissue

9

Top

10th

Grooves

11

Grooves

12th

upper reinforcement

13

Edges

14

Chamfer

15

blanket

16

Support structure

17th

Steel reinforcement

18th

In-situ concrete

19th

Groove

20th

Beam

21

Formwork panel strips

22

Embarrassment

23

Beam reinforcement

24th

Foundation strips

25th

Soil nail

26

Formwork panel strips

27

Recess

28

wall

29

Gutters

30th

Soil nail

31

ground

32

Floor track

33

Cover rail

34

Tie rod

35

Insulation layer

36

nail

Claims (14)

1. Thin concrecte shuttering panel which can be transported and laid manually and is intended for a reinforced-concrete structural unit, which panel consists of a flat plate and exhibits a reinforcement (4) which provides only the strength of the shuttering panel (1) desired in the installed state, said reinforcement comprising at least two intersecting groups of filaments (5, 6), which consist of corrosion-resistant material and are embedded in the concrete at least in that region of the shuttering panel which, in the installed state, is subjected to tensile stressing, the borders (13) of the shuttering panel being chamfered on the side (9) facing the in-situ concrete by a chamfer extending to the upper side of the shuttering panel, such that the reinforcement (17) which is to be installed in the reinforced-concrete structural unit can be laid directly onto the shuttering panel and is thus also protected against corrosion in the joint region, and that surface of the shuttering panel which faces the in-situ concrete (18) and is substantially flat being designed such that, in the installed state, intimate bonding is ensured between the shuttering panel and the in-situ concrete.
2. Shuttering panel according to claim 1, characterized in that a reinforcement (12) comprising intersecting groups of filaments (5, 6) is also embedded in the concrete in that region of the shuttering panel (1) which, in the installed state, is subjected to compression.
3. Shuttering panel according to claim 1 or 2, characterized in that the groups of filaments (5, 6) run parallel to the sides (13) of the shuttering panel (1).
4. Shuttering panel according to claim 1 or 2, characterized in that the groups of filaments (5, 6) are connected to one another at the points of interception of their filaments by adhesive bonding, welding or coating.
5. Shuttering panel according to claim 1 or 2, characterized in that the groups of filaments (5, 6) are interwoven with one another.
6. Shuttering panel according to claim 1 or 2, characterized in that the groups of filaments (5, 6) comprise glass fibres.
7. Shuttering panel according to claim 1 or 2, characterized in that the weight per unit area of the reinforcement is from 50 g/m² to 200 g/m².
8. Shuttering panel according to one of the preceding claims, characterized in that the side (9) of the shuttering panel (1) which is provided for the application of the in-situ concrete (18) exhibits a shaping which increases the adherence between the shuttering panel and the in-situ concrete.
9. Shuttering panel according to claim 8, characterized in that the side (9) of the shuttering panel (1) which is provided for the application of the in-situ concrete (18) is provided with undercut recesses (10).
10. Shuttering panel according to one of the preceding claims, characterized in that the shuttering panel (1) has a thickness of at least 2 cm.
11. Shuttering panel according to one of the preceding claims, characterized in that the shuttering panel (1) preferably has a length of approximately 100 cm and a width of approximately 50 cm.
12. Shuttering panel according to one of the preceding claims, characterized in that the filaments inserted into the shuttering panel (1) consist of alkali-resistant glass fibres.
13. Shuttering panel according to one of the preceding claims, characterized in that, on the side (3) remote from the in-situ concrete (18), the shuttering panel (1) exhibits an insulating layer (35).
14. Shuttering panel according to claim 13, characterized in that the insulating layer (35) is fastened on the shuttering panel (1) by means of anchoring elements (36).

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