DE102008061623A1 - formwork beams - Google Patents

Abstract

The invention relates to a formwork support (10) with a web (12) which is connected at its first long side to a first belt (14) and at its second long side to a second belt (16). At least one of the two straps (14; 16) has a layer of hardwood, in particular a layer of birch wood.

Description

Technical area

The The invention relates to a formwork support. In the area of building are used for enclosing building ceilings or Used walls shuttering panels. These formwork panels be desired by formworks in the desired Position held. When formworking ceilings, the formwork panels are used towards the bottom through lattice-shaped formwork beams supported and supported by supports. Dependent on the size and severity of the to be supported Ceiling or object to be supported Formwork carriers can accommodate different high loads.

State of the art

From the US 6,012,262 is a formwork support known, which has a web and two straps. In this case, both the web and the straps each consist of coarse particle boards or from chips or similarly produced plates. Furthermore, formwork supports are known in which the straps have a plurality of layers, wherein individual layers can be reinforced by fibers, in particular by glass fibers. These carriers are characterized by a particularly high load capacity and, due to complex manufacturing processes, high costs.

Presentation of the invention

Of the Invention is based on the object, a formwork support to provide the known problems of the prior art solves and further favorable in its production is and is suitable to absorb high loads.

The Solution of the problem is achieved by the subject of the claim 1. Preferred embodiments will become apparent from the dependent claims.

As a result, has the formwork support according to the invention a bridge on, on its first long side with a first Strap and the second long side with a second strap connected is. In this case, at least one of the two straps one Layer of hardwood, especially a layer of birch wood on. Hardwood, especially birch, is characterized by the fact that it is particularly tough and elastic and good mechanical-technological Has properties to withstand the high loads and So a particularly resilient formwork beam available to deliver. Furthermore, due to the increased cultivation share of Hardwood compared the prices of hardwood in recent years remained stable with the prices of softwood, so that economical use of hardwood, in particular birch wood, advantageous for the use of formwork beams is. Previous experiments also showed that the inventive Formwork beams compared with those by the applicant under the name H20 offered carrier twice the carrying capacity Having a standardized test procedure.

According to one preferred embodiment is the fiber direction of the layer of hardwood substantially parallel to the longitudinal direction of the formwork support. Due to this parallel alignment of the wood layer It is particularly advantageous possible on the formwork support acting load forces, in particular the vertical forces, take.

In Another preferred embodiment is the layer of hardwood at least 2 mm thick. By using one already 2 mm thick layer, so-called veneer, made of hardwood becomes one enormous improvement of the load capacity of the formwork support reached.

According to one another particularly preferred embodiment, the Formwork support as outermost layer a layer of hardwood on. Due to its elastic properties The hardwood, especially the birch wood, is very good as the outermost Layer and it is also very good for recording the high load forces especially in the area of Support.

According to one Another embodiment, the formwork support a connected to the web first layer, which by at least a connection layer in at least a portion between the first layer and a second layer in adhesion with the second layer is. By using a layered Construction, with a particular layer of hardwood, is a special resilient formwork support created.

In a further preferred embodiment of the formwork support, the center of the annual rings of the layer of hardwood, around which the annual rings are arranged substantially concentric, preferably in the region of the outer, the web opposite side of the belt is formed approximately centrally. By this arrangement, it is possible to optimally absorb the forces acting on the formwork support, since the hardwood layer, in analogy to a vault, distributes the centrally occurring vertical forces particularly advantageous to the entire belt width and the formwork support is particularly resilient. Furthermore, in particular birch wood in its main growing area in Scandinavia, especially in small trunk diameters available, which accommodates this arrangement.

According to one preferred embodiment are at least two layers bonded, in particular polyurethane being used as adhesive. Polyurethane is a very good adhesive.

Further it is conceivable that the formwork support in the connecting layer Reinforcing fibers, in particular glass fibers. fibers, especially glass fibers, are particularly advantageous to Loads which are applied to the formwork support, evenly distributed. This can be done at a unevenly applied load a uniform Load distribution over the entire formwork beam be ensured.

Further are in a further preferred embodiment the Fibers of the connecting layer largely to one in the carrier longitudinal direction and arranged on the other in the carrier transverse direction. there In particular, about 20% are longitudinal fibers and about 80% transverse fibers available. As a result, it is particularly advantageous in the connection layer possible loads, which are introduced through the web evenly over the entire width of the first layer and the second layer to distribute. Especially the high proportion of transverse fibers, with other shares, such. B. up to 100% of transverse fibers are conceivable, it allows Particularly advantageous load particularly evenly over to distribute the entire width of the layers. In case of stress Thus, a penetration of the web in the layers of the straps due Too much stress avoided because the introduced through the web Vertical forces distributed over the width of the tie layer become.

According to one preferred embodiment, the fibers are the tie layer and / or the reinforcing layer arbitrarily arranged. By the arrangement of the fibers in a diagonal direction or as a tissue, Scrim or fleece, it is particularly advantageous possible the vertical forces introduced into the formwork support to distribute over the entire belt width.

The Portions of the fibers in the tie layer are up to 50 Vol .-%, in particular up to 35 vol .-%. This will be a special load-bearing formwork support provided, which also has particularly well bonded together layers.

Further the bonding layer comprises polypropylene. Polypropylene draws especially when used in a formwork support advantageous in that it is a very light plastic, which, however, a particularly high rigidity and hardness having.

It further suggests that the outermost layer at least partly to color. This is the utmost Layer on their outer surfaces encased with a suitable plastic.

According to one Another preferred embodiment has the surface the outermost layer at least in sections an anti-slip coating on. This anti-slip coating can be through notches and / or protrusions in the surface of the outermost Layer be formed. This makes it possible to get one particularly safe formwork beams available to put, as a slipping on the formwork support or slipping when gripping the formwork support prevented becomes.

The Notches and the projections of the anti-slip coating in the surface of the outermost layer can be arranged so that they are in a subarea a lettering or a graphic represent. That's the way it is advantageously possible, a particularly safe formwork support to provide at the same time over has a high recognition value.

According to one particularly preferred embodiment of the formwork support the first layer or the second layer is made of spruce wood, in particular from sorted spruce wood. Spruce wood stands out by that it is well available and cheap is.

Of the Bridge, which serves to connect the two straps, is in one preferred embodiment formed of plywood, in particular of cross-ply poplar plywood. poplar as well as poplar plywood are characterized by good static properties and a cheap price. That's what makes it special advantageously possible, a particularly durable formwork support to make available, which in return also inexpensive is.

According to one further particularly preferred embodiment the strength of the bonding layer maximum up to 4 mm, in particular up to 1.5 mm. By using layers of these Thickness is a particularly strong formwork support for Provided.

The Shutterings according to the invention are suitable particularly advantageous for use in a variety of formwork beams, shuttering panels and formwork supports comprising formwork system.

Short description of the drawing

following the invention is illustrated by way of example in the drawing Embodiment explained in more detail.

The FIG. 1 shows a cross section through an inventive device Formwork support.

Detailed description a preferred embodiment of the invention

In the figure is a formwork support 10 represented, which at least one web 12 and two straps connected to it 14 and 16 having.

The jetty 12 is preferably formed of cross-ply poplar plywood, resulting in the stability of the web 12 improved. On the two long sides of the bridge is in each case at least one wedge 26 educated. The wedge 26 or the wedges form a finger joint and engage the two straps 14 and 16 , The wedge or wedges 26 of the footbridge 12 are substantially V-shaped and have a flattened tip 28 on.

The two straps 14 . 16 have in the case shown an identical layer structure from the inside out. To make the description easier to understand, only one of the identical straps will be used 14 and 16 described. Alternatively, it is also possible to carry out the formwork support with different straps, wherein at least one of the two belts has an approximately identical structure with the described.

The finger joint is engaged with a first layer 18 , The engagement of the wedge or wedges 26 is ensured by an adhesive. Alternative anchoring of the bridge in the straps are possible.

The first shift 18 is made of spruce wood. Alternatively, a design of hardwood, especially birch wood, possible. To the first shift 18 closes a connection layer 20 at. This connection layer 20 is preferably constructed of a fibrous material and used as an adhesive to provide a bond between the first layer 18 and the second layer 22 to produce polyurethane. In the connection layer 20 are fibers with a fiber content of up to 50 vol .-%, in particular up to 35 vol .-%. On the one hand, this ratio between fibers and binder ensures particularly well that the first layer 18 and the second layer 22 good adherence, and on the other hand, that a particularly good carrying capacity of the carrier is produced.

The fibers within the tie layer 20 are arranged so that 20% of the fibers are aligned in the longitudinal direction of the carrier, that is, the fibers are substantially parallel to each other in the longitudinal direction. The remaining 80% of the fibers are arranged transversely to the carrier longitudinal direction. The transverse fibers of the tie layer 20 contribute in the advanced load condition, so with a high load on the formwork support that the centrally occurring vertical forces are distributed evenly over the entire belt width. Thus, penetration of the wedge into the belt can be avoided particularly well and the formwork support is more resilient.

In another embodiment, the fibers are in the tie layer 20 arbitrarily with respect to the longitudinal and transverse alignment, in particular in a diagonal orientation, arranged. In all cases, in this case, the shape of a fabric, a fabric or a nonwoven with optionally different fiber components in different directions proves to be particularly advantageous, wherein the fibers are arranged in each case substantially parallel to the surface of the individual layers.

To the connection layer 20 closes a second layer 22 at. This layer 22 is made of birch or birch veneer, this layer 22 at least 2 mm thick.

The layer of birch wood or birch wood veneer has annual rings 30 on. The circular center of the annual rings 30 around which the annual rings are arranged substantially concentric, is located at the outer, the bridge 12 opposite side of the second layer 22 or outside the second layer 22 , The annual rings 30 are preferably centered in the second layer 22 arranged. In this way, the annual rings form a vault-like structure, which makes it possible to absorb the introduced vertical forces and evenly over the entire width of the second layer 22 to distribute.

The second layer 22 is designed so that the circular center of the annual rings 30 over the entire length of the second layer 22 relative to the jetty 12 essentially not shifts. In other words, you would use the formwork girder 10 in longitudinal direction at any point, so would on all side profiles, so the side profile of the front and the rear end of the formwork support 10 and the two side profiles created by sharing, the circular center of the annual rings 30 do not shift and the course of the annual rings 30 look essentially the same.

The outermost layer 22 is preferred with egg dyed color. This is the outermost layer 22 at least partially encased with a suitable plastic. This plastic can be chosen to have good anti-slip properties.

Alternatively, it is possible the formwork support 10 to stain completely or at least partially with a paint or to coat it with the plastic.

Furthermore, it is possible the outermost layer 22 provided with indentations and / or protrusions in the surface. This gives the outermost layer 22 a non-smooth surface profile and slipping on the outermost layer is prevented. Furthermore, it is prevented that formwork panels on the outermost layer 22 accidentally slip. The indentations and / or projections may be arranged so that they form a lettering or a graphic in a partial area. The lettering or graphics may include the name of the manufacturing company and / or instructions for use of the formwork support 10 contain.

The connection layer 20 has a layer thickness of up to 4 mm, in particular up to 1.5 mm. The first shift 18 and the outermost layer 22 By contrast, have a layer thickness of up to several centimeters, in particular up to 39 mm per layer. It is also possible a formwork support with a plurality of layers 18 and 20 if at least one layer 22 hardwood, in particular birch wood, preferably used as outermost layer.

In a further embodiment, it is possible the formwork support 10 with a first layer 18 of hardwood, in particular birch, an outer layer 22 made of a different material and a bonding layer 20 to produce with the aforementioned properties.

It is also possible a formwork support with a single layer 18 existing belt 14 . 16 produce, which is particularly resilient due to the birch wood.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - US 6012262 [0002]

Claims (19)

Formwork support ( 10 ) with a bridge ( 12 ), which at its first long side with a first strap ( 14 ) and on its second long side with a second strap ( 16 ), wherein at least one of the two straps ( 14 ; 16 ) comprises a layer of hardwood, in particular birch wood. Formwork support according to claim 1, characterized in that the fiber direction of the layer of hardwood substantially parallel to the longitudinal direction of the formwork support ( 10 ). Formwork support according to claim 1 or 2, characterized in that the layer of hardwood at least 2 mm thick. Formwork support according to one of the preceding Claims, characterized in that the outermost Layer of hardwood. Formwork support according to one of the preceding claims, characterized in that one with the web ( 12 ) first layer ( 18 ) by at least one connecting layer ( 20 ) in at least a portion between the first layer ( 18 ) and a second layer ( 22 ) in adhesion with the second layer ( 22 ) stands. Formwork support according to one of the preceding claims, characterized in that the center of the annual rings ( 30 ) of the layer of hardwood around which the annual rings ( 30 ) are arranged substantially concentrically, in the region of the outer, the web ( 12 ) opposite side of the belt is preferably formed approximately centrally. Formwork support according to claim 5 or 6, characterized in that at least two layers ( 18 - 22 ), in particular polyurethane being used as the adhesive. Formwork support according to one of claims 5 to 7, characterized in that the connecting layer ( 20 ) Reinforcing fibers, in particular glass fibers or the connecting layer ( 20 ) consists of a layer of hardwood, whose fibers are preferably arranged transversely to the longitudinal direction consists. Formwork support according to claim 8, characterized in that the connecting layer ( 20 ) has longitudinal reinforcing fibers arranged largely in the longitudinal direction of the carrier and transversely extending transverse reinforcing fibers in unequal proportions, with in particular about 20% longitudinal reinforcing fibers and about 80% transverse reinforcing fibers being present. Formwork support according to claim 8, characterized in that the fibers of the bonding layer ( 20 ) are arranged arbitrarily. Formwork support according to one of claims 8 to 10, characterized in that the proportion of reinforcing fibers in the bonding layer ( 20 ) up to 50% by volume, in particular up to 35% by volume. Formwork support according to one of claims 5 to 11, characterized in that the connecting layer ( 20 ) Polypropylene. Formwork support according to one of the preceding Claims, characterized in that the surface the outermost layer at least partially colored is. Formwork support according to one of the preceding Claims, characterized in that on the surface the outermost layer formed an anti-slip coating is. Formwork support according to claim 14, characterized in that that the anti-slip coating by notches and / or protrusions is formed, wherein at least a portion of the notches and / or the projections represents a lettering or a graphic. Formwork support according to one of claims 5 to 15, characterized in that the first layer ( 18 ) is made of spruce wood, in particular of assorted spruce wood. Formwork support according to one of the preceding claims, characterized in that the web ( 12 ) is formed of poplar plywood, in particular from crosswise layers having poplar plywood. Formwork support according to one of claims 5 to 17, characterized in that the layer thickness of the bonding layer ( 20 ) is up to 4 mm, in particular up to 1.5 mm. Formwork system with at least one formwork support ( 10 ) according to any one of the preceding claims.