DE102016113190A1 - Process for the production of concrete spacers - Google Patents

Abstract

The invention relates to a method for the production of concrete spacers. It is an object of the invention to produce spacers using cast concrete, at least one casting mold and spacer fastening means inserted into the spacer. This is achieved by four process steps. First, a flat concrete slab is produced in a mold. Subsequently, the spacer fasteners are inserted into the open top of the poured concrete slab. After curing, the concrete slab is demolded, so that finally by machine breaking the concrete slab a plurality of spacer bodies are generated.

Description

The invention relates to a method for producing concrete spacers according to the preamble of patent claim 1.

In the construction industry spacer body eg. When creating concrete walls and beams used to secure a defined distance between the formwork on the one hand and the reinforcement or the reinforcing mats on the other. The spacers also ensure that the reinforcement is covered with a certain layer thickness of concrete, the spacer being fully integrated into the cured concrete mass of the component. Cement-bonded spacers therefore have the elementary advantage over, for example, those based on plastics that they can be fully integrated in the concrete and thus do not represent any foreign bodies in the concrete.

Concrete spacers are usually produced either in a casting process in different forms trained in mass or obtained in a concrete extrusion process.

Known is an extrusion process for producing spacers made of cement-bonded material, preferably fiber concrete, in which a profile strand is extruded from this cement-bonded material and then cut into individual spacers ( DE-PS 30 47 116 ). This known method is used for the production of plate-shaped or disc-shaped spacers which have a slot open towards the periphery of the spacer, with which the respective spacer can be pushed onto a reinforcing steel for fastening.

Another publication is a procedure ( DE-OS 34 42 918 ), in which a binding wire is inserted in such an extruded profile strand of cement-bonded material from one side and then cut off.

Instead of, for example, to be carried out with an extruder extrusion process for the production of spacers, it is also known to produce spacers by a casting process in molds ( DE-GM 19 96 751 ). Such a molded product is clearly defined in its dimension and can not, like an extruded spacer, be made from a profile strand through sections of selectable length in individually different, needs-based dimensions. Such casting manufacturing of the spacers is relatively time consuming and costly over the extrusion process, but allows for an unrestricted design in terms of molding.

Both procedures are subject to fundamental restrictions and procedural necessities, which will be considered in more detail below.

The production of spacer bodies in concrete casting is a widely used and proven technique in which each spacer originates from a separate mold. After entering the concrete into the mold holding body are inserted into the not yet fully solidified spacer, with which the spacer is attached at a later date then to be determined in their distance to a casing reinforcement. These may be metallic bodies such as retaining wires as well as plastic bodies which are designed, for example, as clamps.

In this process, a defined time sequence is required, since only a certain hardening of the cast concrete must be done before a Ausschalung the individual spacers from the molds is possible. After that, it often comes to a post-treatment and maturation, for example, in a thermal aftertreatment, which should favor, for example, the maturation process of the concrete body.

The extrusion process provides that spacer bodies are extruded by machine, with considerable limitations in terms of shaping and other conditions for the introduction of holding bodies in the spacer body.

Another aspect of the present invention is that experimentally working with spacers has shown that a roughened outer surface of a spacer body basically has a positive effect on the connection of a prefabricated spacer to the in-situ concrete, for example, in a concrete wall, still as liquid concrete is brought into connection with the already cured spacer. Here, in conventional spacers produced by casting, there is basically the problem that the cement paste applied externally to casting bodies counteracts an ideal chemical-physical connection of the preproduced spacer with the in situ surrounding concrete in the later concrete wall to some extent, thereby increasing the risk of immigration of chemical substances in a fine gap area between spacer body shell and surrounding in-situ concrete is favored.

From the publication DE 4120215 A1 is already known spacer body, which have been produced in the casting process by a roughening subsequent surface treatment and so to achieve a surface that can form a better connection to the in-situ concrete. This is a treatment that can be done only after curing of the spacer and also means a significant technical effort.

Against this background, it is the object of the present method to simplify the production of spacer bodies on the one hand and thus to allow an acceleration of the manufacturing process, especially in mass-produced spacer bodies. On the other hand, the connection of the spacer with the in-situ concrete is also to be improved in that the finished spacer body has a rough surface and thus better teeth of the spacer body on its outer shell with the in-situ concrete is possible.

This is achieved with the method according to claim 1 and a spacer, which is produced by the inventive method, according to claims 7 successive.

The back claims have advantageous embodiments of the method to the subject.

The method according to the invention for producing the concrete spacer body provides for different process steps that take place one after the other. In the first process step, the starting material for the later spacer body, namely a plate-shaped cast concrete cuboid, is pre-produced. It is relevant in this case that this pre-produced flat cast concrete slab makes it possible to break this slab later into the individual spacer bodies, which is why it is expedient to introduce predetermined breaking points in the cast concrete slab via the casting mold, which correspond to the later mechanical cleaning of the break edges of the spacer bodies.

In an exemplary solution is provided here to arrange at the bottom of the mold for the production of the plates grid-like webs, which protrude into the cast concrete slab on the underside and run after the shuttering as groove-like depressions on the underside in the concrete slabs and thus favor a break at these points.

However, it is relevant that these predetermined breaking points only in a small depth in the pre-produced concrete slab, since a stated object of the invention is to effect the largest possible area outer shell of the spacer body, which consists of a free-broken concrete material, which is ideally with a later cast in situ concrete in a concrete building connects. In this way it is achieved that an entry of pollutants, in particular of salts in the range of application of the concrete body, for example, under water is prevented by the better connection of spacer body and actual concrete structure.

Another essential aspect of the method according to the invention is that the bottom plate of the mold for the base plate to be crushed already has shapes in the form of depressions, which define the subsequent bearing surface of the spacer body on a shuttering wall and thus also the area later recognizable in exposed concrete. This is a strength conventionally produced in the casting process concrete spacers that here the bearing surfaces, points or lines can be produced very accurately and as desired.

The inventive method now allows, despite the broken outer surfaces of the spacer body to produce a defined cast support point on the casing and thus on the outer surface of the concrete building. This can be done in the form of a point contact point or in the form of several projections or a small contact surface. Here is basically any shape design on the definition of the bottom plate of the mold possible. The bottom plate of the mold comprises, according to the number of the spacer to be broken from the mold a corresponding analog number of wells to form the support surface in the desired shape, wherein the wells are each assigned to a broken in the last step from the plate spacer, whereby the arrangement of these wells , the placement of the spacer fastening means in the concrete slab and the course of the fault lines in the production of the single spacers from the plate in coordination with each other

In terms of process technology, after the cast concrete has been introduced into the above-described receiving mold and the previously described casting mold, the fastening means are introduced. These are introduced on the upper side into the surface of the cast starting plate and arranged according to the number of spacer bodies to be broken in a defined grid.

In an advantageous embodiment of the method, this introduction of the fastening means is carried out automatically in the surface of the not yet cured cast concrete and after a precisely predetermined grid.

Basically, it is provided here that the method according to the invention allows a maximum of automation. That is, it is intended to perform the filling of the molds with the cast concrete, the loading of the molds with fastening means as well as the breaking of the spacers from the plate automatically on corresponding conveyors such as conveyor belts and the like.

Analogously, it is also envisaged to carry out the further method steps as automated as possible. After a defined curing process in terms of duration but also temperature and humidity, the starting plate is completed in a maturity, which allows the actual breaking of the spacer body. For this purpose, the plate of a machine device for breaking the concrete slab is fed into individual sections, ideally also automated via conveyor belts.

There is now the application of a breaking force in the cast output plate. In this case, different process paths are alternatively possible. A solution according to the invention provides in this case that the plate is broken in a first step in the transverse or longitudinal direction by a linear breaking device in strip sections. These now mutually parallel strip portions are fed in a second process step of another linearly extending breaking device which is arranged approximately at right angles to the first breaking device and thus breaks from the strip-shaped sections of the cast concrete slab cuboid or rectangular spacer body in the desired size.

Guiding means are provided for this purpose, which press the strip-broken sections of the starting plate against one another and feed them to the next method step and thus also convey the starting plate in the method.

Furthermore, it is relevant, in order to achieve circumferential broken edges on the spacer bodies, to break the outer edges of the precast concrete slab in one process step. That is, for example, in the use of the above-described linear fracture devices successively break a narrow edge region at the outer edges of the cast plate and thus to ensure that also the spacer body, which are arranged on the output plate outboard circumferentially broken outer surfaces. An alternative solution of the method provides that in a single fracture operation by a grid-like breaking device, the spacer body are broken from the plate. For this purpose, the breaker grid is lowered completely onto the starting plate and pressed onto the starting plate with a defined pressure. As a result, the voltage is registered in the region of the overlying grid lines in the cast plate and there are defined breaklines, which extend approximately vertically through the cast plate and thus break the desired spacer body out of the plate. In this way, a complete plate can be broken into individual spacers advantageously with a single step.

It may be a special feature of the method in a special embodiment of the method that in the casting mold of the base plate, the feet serving as shuttering surfaces later are variable in that the base plate of the casting mold is made interchangeable. Thus, in a basic mold, a variety of bearing surfaces of the spacer bodies can be realized.

The height of the starting plate and thus the depth of the later spacer body and thus the distance between the casing and reinforcement can be according to the invention about 5-20 cm. This allows use of the spacer body in many technical applications and in a variety of later realizable concrete structures.

In the procedural solution of the fracture process with two subsequent axis directions of the cast plate, the invention provides, in the first method step, to feed the starting plate onto a conveying means of the fracture device. This is arranged transversely to the conveying direction of the starting plate above the conveyor in an advantageous embodiment of the method, wherein the output plate passed through the width of the spacer body to be broken under the strip-like breaking device thus gradually producing the strip-like portions of the starting plate. In the next process step, this now present in strips output plate is pressed together by holding arms and out, which are also arranged transversely to the original conveying direction and thus compress the generated strips of the output plate in the original conveying direction together.

In a second method step, these strips, which are pressed together in a plate-shaped manner by the holder arms, are then broken transversely to the original conveying direction. This is done either directly via the previous funding or the held output plate is continued transversely to the original conveying direction and fed to a second breaking device, which breaks transversely to the first breaking device, the now strip-shaped sections of the original output plate in single body. Finally, then these broken spacer body directly one continuing promotion, for example, in packaging units, such as transport bags or the like can be supplied.

From this method, go forth the novel spacer body according to the invention, which are characterized in that they are formed on their lateral in a concrete building over the entire surface built peripheral edges of broken concrete planks. However, the bearing surfaces for shuttering are produced by casting and thus formed in their shape variable and uniform and thus provide clean and aesthetically pleasing support points or surfaces on the outside of a concrete structure. The armoring pointing, provided with fastening means areas of the spacer body also have not broken and smooth surfaces, as here also no breakage occurs. That is, the opposite mounting surface to the reinforcement as well as the support surface to the shuttering have defined attractive and functional surfaces.

The lateral surfaces of the spacer body, with which the connection has to be made in the concrete building are roughly broken and thus ideal to ensure a connection between the castable concrete and the already prefabricated spacer bodies. Pollutant input through the fine gaps formed between, for example, conventional cast spacer bodies between the prefabricated spacer body and the later cast concrete can thus be avoided. In this way, the spacers according to the invention by the method according to the invention meet the highest requirements, especially in use in concrete structures, for example, should have existed in the sea, since in particular here the corrosion of the reinforcements installed in concrete represents a difficult solvable technical problem.

The invention will be described in more detail with reference to drawings. Show it

1 a perspective top view of the poured concrete slab 1 with grid-like spacers mounted therein fasteners;

2 the concrete slab according to the invention 1 in a side perspective view;

3 a detailed perspective view of the concrete slab top as well

4 a perspective bottom view of the poured concrete slab 1 with raster-like contact areas.

In the perspective plan view of the poured concrete slab 1 with grid-like spacer spacers placed therein 2 It becomes clear that the concrete slab is prefabricated as a starting material for a large number of later spacers. In the present example, the fasteners used are 2 around attachment wires, which are arranged in pairs in the spacers. In addition, on the surface of the concrete slab 1 Rupture lines visible, the grid-like concrete slab 1 cover and limit each a later spacer.

In 2 is also the concrete slab according to the invention 1 shown in a side perspective view, wherein the protruding from the top spacer fasteners 2 as well as those on the underside of the concrete slab 1 running footprints 3 , which are formed in this case half-shell-shaped and thus produce an approximately punctiform uprising in the finished concrete product.

As already described, this is merely an exemplary representation of the possible footprint. This can also be square, round and flat. It can also consist of several, for example 3 or 4 Stand feet exist, form a pyramidenformige or star-shaped footprint.

There are on the bottom between these footprints 3 also predetermined breaking joints 4 recognizable, which have already been introduced via the mold itself in the concrete slab. This is also in 4 to recognize.

3 indicates that on the top of the concrete slab such Sollbruchfugen 4 are arranged in an exemplary representation square to each other in a grid extending. It can be seen hereby that the arrangement of the spacer fixing means used on the top 2 centered and also grid-like in the through the predetermined breaking joints 4 predetermined spacer body are used.

In 4 It is also clear that the arrangement of the contact areas as well as the predetermined breaking joints running between the contact areas 4 are arranged according to this grid as the fasteners inserted on the upper side, so that these structural elements are arranged in such a coordinated manner on the concrete slab that the final crushing process and thus the actual production process of the individual spacer body here clear assignments of footprint, actual concrete spacer body and arranged in this fasteners ,

Given by the method thus creates a standardized spacer body, which nevertheless deviates slightly in each spacer body from each other, as the 4 circumferential outer surfaces, which are surrounded by the Ortbeton when using the spacer, are formed differently due to the generation by a fracture process at each break and cause an ideal connection to the in-situ concrete.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 3047116 [0004]
• DE 3442918 [0005]
• DE 1996751 [0006]
• DE 4120215 A1 [0012]

Claims (12)

Method for producing concrete spacer bodies using cast concrete, at least one casting mold and spacer fastening means inserted into the spacer, characterized by the method steps: Producing a flat concrete slab in a casting mold, Inserting spacer fasteners into the open top of the poured concrete slab, - Curing and subsequent demolding of the concrete slab and - Machining the concrete slab to produce a plurality of spacer bodies from the concrete slab. A method for the production of concrete spacer bodies according to claim 1, characterized in that predetermined breaking points are introduced into the concrete slab, wherein the machine breaking of the concrete slab takes place along the predetermined breaking points. A method for producing concrete spacer bodies according to claim 2, characterized in that the mold for the concrete slab has specially shaped projections for forming the predetermined breaking points in the concrete slab. Method according to one of the preceding claims, characterized in that the mold for the concrete slab specially shaped recesses for forming bearing surfaces, points or edges on the opposite side of the spacer fastening means of concrete spacer body, said recesses each one in the last step the plate broken spacers are assigned, whereby the arrangement of these recesses, the placement of the spacer fastening means and the course of the fault lines in coordination with each other. Method according to one of the preceding claims, characterized in that the concrete slab plate has a thickness in the range of about 0.05 m to 0.20 m. Method according to one of the preceding claims, characterized in that the introduction of the spacer fastening means in the concrete slab automated and after a defined uniform grid immediately after the casting process or after curing of the cast concrete slab, whereby the fastening means formed in the after machine crushing Concrete spacer body are arranged centered aligned. Method according to one of the preceding claims, characterized in that the hardened cast plate is broken in a first step in the transverse or longitudinal direction by a linear breaking device in strip portions, which are arranged in parallel to each other in a second step another linearly extending breaking device, which is approximately is arranged at right angles to the first breaking device and thus breaks from the strip-shaped sections of the cast concrete slab cuboid or rectangular spacer body in the desired size. Method according to one of the preceding claims 1 to 6, characterized in that a plurality of spacer bodies of the plate to be broken in a single break operation by a grid-like design breaking tool, for which the lattice-like design breaking tool, the disk surface is completely spanning lowered onto the cast plate, and with a defined nip pressure is pressed onto the cast plate. Concrete spacer body for distance determination of reinforcements in concrete structures with fastener fasteners fastened in concrete produced according to one of the method claims 1 to 8, characterized in that the concrete spacer body on its lateral, enclosed in the concrete structure of in-situ concrete wall surfaces full-surface, formed by machine breaking from the flat concrete slab, has broken roughened surfaces and the spacer mounting means opposite side of the concrete spacer body is designed as exposed concrete design. Concrete spacer body according to claim 9, characterized in that the concrete spacer body has approximately a cubic or cuboidal shape. Concrete spacer body according to one of the preceding claims 9 or 10, characterized in that the on the spacer fastening means for reinforcing opposite, the shutter side surface arranged Sichtbetongestaltung half-shell, tapered, tapering in an edge or surface, in a plurality of support points, edges or surfaces tapered or formed as a combination of these forms. Concrete spacer body according to one of the preceding claims 9 to 11, characterized in that the concrete spacer body has a tapered shape starting from the reinforcing side towards the shuttering side.

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