WO2023089058A1

WO2023089058A1 - Concrete slab construction having a joining element made of concrete for joining concrete slabs together, and method for producing a concrete slab construction

Info

Publication number: WO2023089058A1
Application number: PCT/EP2022/082329
Authority: WO
Inventors: Josef Peter Kurath-Grollmann
Original assignee: Cpc Ag
Priority date: 2021-11-17
Filing date: 2022-11-17
Publication date: 2023-05-25
Also published as: WO2023088555A1; CA3237759A1

Abstract

The present invention relates to a concrete slab construction (14) comprising at least one concrete slab (2, 2') and at least one joining element (1) which is made of concrete for connecting concrete slabs (2, 2') and which is to be fastened in or on a concrete slab (2, 2'). The joining element (1) has a joining body with an upper region and a lower region, and a cross section of the joining body between the upper region and the lower region has, on one side, and in particular also on another side, at least one notch or indentation. The concrete slab (2, 2') has, along the lateral circumference thereof and/or in a cut-out (15) between the top side and bottom side, at least one similarly shaped indentation (20, 20') or notch corresponding to the joining element (1). In an intermediate space between the cut-out (15) in the concrete slab (2, 2') or between the two concrete slabs (2, 2') and the joining element (1) there is a filler material. Also disclosed are a method for producing a concrete slab construction with the aid of a joining element, a method for producing a joining element, a method for producing a concrete slab for the concrete slab construction, and a use of the joining element and the concrete slab construction.

Description

CONCRETE PANEL CONSTRUCTION WITH A CONCRETE JOINT FOR JOINING CONCRETE PANELS AND METHOD OF MAKING A CONCRETE PANEL CONSTRUCTION

TECHNICAL FIELD OF THE INVENTION

The present invention relates to a concrete slab construction with a joining element for joining or Joining concrete slabs. Furthermore, the invention relates to a method for producing a concrete slab construction with the aid of a joining element, a method for producing a joining element and a method for producing a concrete slab for the concrete slab construction. Furthermore, the invention relates to the use of the joining element and the concrete slab construction.

BACKGROUND OF THE INVENTION

In construction, the classic reinforced concrete construction method is still very widespread. Typical reinforced concrete components include components subject to bending stress, such as ceilings, beams or floor slabs. In particular, massive, large-volume components such as bridge pillars or retaining walls are usually made of reinforced concrete, since concrete is a relatively inexpensive material. is disadvantageous The fact that such solid components have a high dead weight and that a great deal of carbon dioxide is released to produce cement for the large quantities of concrete required (approx . 590 kg CO2 per 1000 kg cement ), which in view of the current climate protection discussion is seen as problematic. Therefore, instead of large-volume components, attempts are increasingly being made to use thin and therefore lighter concrete slabs as components, which require significantly less concrete and thus cement for production. These concrete slabs are often referred to as FRC slabs (where FRC is an abbreviation for "fiber reinforced concrete"), in particular as CPC slabs (where CPC is an abbreviation for "carbon prestressed concrete"), which are particularly resilient and load-bearing, realized . This also has the advantage that the concrete slabs can be produced in a factory under optimal conditions as prefabricated components (semi-finished products) in the desired sizes and then later only have to be joined or assembled on the construction site. On the other hand, the complete erection of massive reinforced concrete structures on site does not always run smoothly due to a certain dependence on the prevailing weather conditions. Frost , extreme heat or heavy precipitation can affect the setting process of the concrete and thus have an impact on the quality of the reinforced concrete structure, so that weather conditions must be taken into account during their manufacture. There is therefore a need for means for the simple and rapid creation of resilient and sustainable structures and for suitable manufacturing processes for these means, which in particular require fewer resources and pollute the environment less.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide means which make it possible to create loadable and stable structures from concrete slabs in a simple and quick manner. For this purpose, a joining element for connecting or joining concrete slabs and/or for fastening in or proposed on a concrete slab.

It is an aim of the present invention to propose a concrete slab construction comprising at least one concrete slab and at least one joining element. Various alternatives of such concrete slab constructions are given in claims 1-3.

Furthermore, it is an object of the present invention to provide a method for producing a concrete slab structure by inserting a joining element into a concrete slab or between two concrete slabs. Such a Manufacturing method is proposed in claims 26 and 28 .

Furthermore, it is an aim of the present invention to propose uses of the joining element and of the concrete slab construction. Such uses are set out in claims 39 and 40 .

Finally, an aim of the present invention is to specify a method for producing a joining element and a concrete slab for a concrete slab construction. Such manufacturing methods are proposed in claims 41 and 44 .

Specific variant embodiments of the various aspects of the present invention are set out in the dependent claims.

As part of a concrete construction according to the invention, a joining element made of concrete, in particular made of FRC or CBC, is used for connecting or joining concrete slabs and/or for fastening in or proposed on a concrete slab. The joining element has a joining body with an upper area or a top and a bottom area or an underside, with a cross section (or profile) of the joining body between the upper side and the underside on one (left, right, front or rear) side, and in particular also on another, in particular opposite (right, left, rear or front), side (each) has at least one notch or bulge. The indentation or bulge has in particular two flanks or surfaces tapering to an (optionally rounded but not necessarily pointed) point, in particular flat flanks/surfaces, with the two flanks/surfaces forming or enclosing an obtuse or acute angle cp . For example, the cross section of the joining body is hourglass-shaped. In particular, the joining body is hourglass-shaped (ie rotationally symmetrical between the top and bottom), the top and bottom of the joining element being round or oval, for example. An hourglass-shaped cross-section is one that starts out wide, narrows to a taper, and then widens again. An hourglass-shaped body has a characteristic "constriction" or "constriction" in the middle and has a mirror-symmetrical cross-section with respect to its (vertical) longitudinal axis. Hourglass-shaped bodies are often also rotationally symmetrical about the (vertical) longitudinal axis. A bicone with opposite points is an example of an hourglass-shaped body.

There can be one or more notches or bulges on one or more sides of the joining element—in the case of a cuboid joining element, for example on a left, right, front and/or rear side, in particular on opposite sides such as on the left and right side and/or on the front and rear side. In particular, a joining element can only have indentations or only bulges. In a concrete slab construction, for example, joining elements that only have indentations or those that only have bulges can be used. Alternatively, in a concrete slab construction, for example, both joining elements that only have indentations and those that only have bulges can be used.

Further embodiments of the joining element for use in the concrete slab construction according to the invention are given below.

In one embodiment of the joining element, which with each of the already mentioned and still to be mentioned

Embodiments can be combined, unless conflicting therewith, the indentation or bulge on one side and the indentation or bulge on the other (opposite) side are (substantially) uniform. In particular, the cross section is mirror-symmetrical or point-symmetrical.

In a further embodiment of the joining element, which can be combined with any of the embodiments already mentioned and those to be mentioned, provided it does not contradict this, the indentation or bulge has an upper flank and a lower flank, the upper flank and the lower flank being (substantially) of the same length or of different lengths. In particular, the length ratio of the shorter (/upper) flank to the longer (/lower) flank is in a range from 1:16 to 1:1 or from 1:8 to 1:1 or from 1:4 to 1:1 . The angle a between the upper side and the shorter, upper flank is, for example, in a range from >0° to 89°, in particular from 10° to 89°, even more particularly from 30° to 86°. The angle β between the underside and the longer, lower flank is, for example, in a range from 45° to 89°, in particular from 60° to 89°, even more particularly from 70° to 86°. The length ratio between the upper and lower flank and the angle a between the upper side and the upper flank as well as the angle ß between the lower side and the lower flank are selected in such a way that force can be transmitted from the concrete slab to or from the concrete slabs between where the joining element is arranged on the joining element (and vice versa from the joining element to the concrete slab(s)) takes place in a desired direction or the flow of force through the joining element takes place in a desired way. In many practical cases, the short flank is only a few millimeters long, for example around 4 mm long.

In a further embodiment of the joining element, which can be combined with any of the embodiments already mentioned and those to be mentioned, provided this does not contradict them, the height of the joining body is between the upper side and the lower side is in a range of 2 cm to 10 cm, and/or a width of the joined body between the left side and the right side (at the widest point) is in a range of 2 cm to 10 cm.

In a further embodiment of the joining element, which can be combined with any of the embodiments already mentioned and those yet to be mentioned, unless contradicted, a length of the joining element (perpendicular to the cross section/in the direction of the longest

Extension of the joining element) in a range from 5 cm to 20 m, in particular up to 1 m, more particularly up to 50 cm.

In a further embodiment of the joining element, which can be combined with any of the embodiments already mentioned and those yet to be mentioned, unless contradicting them, a ratio of a diameter of an opening of the notch or of an exit of the bulge to the height of the joining body is in one Range from 1:1 (i.e. 100%/full opening) to 0.5:1 (i.e. 50% opening) .

In a further embodiment of the joining element, which can be combined with any of the forms of execution already mentioned and to be mentioned, unless contradicted, the joining body has an extension on the upper side and/or the underside, the Extension designed in particular as a coupling element for coupling to another component i st.

In a further embodiment of the joining element, which can be combined with each of the embodiments already mentioned and those to be mentioned, provided that this is not contradicted, another joining body is arranged on the extension. In particular, the further joining body and the extension are formed together in one piece.

In a further embodiment of the joining element, which can be combined with any of the embodiments already mentioned and those to be mentioned, unless contradicted, the joining body has at least one other between the upper side and the underside, at least on one side notch or at least one further bulge on . In this case, further notches or further bulges can be added to the existing notches. The same applies to existing bulges, to which further bulges or further indentations can be added. So the joining element z. B. have an indentation and a bulge on the same side.

In a further embodiment of the joining element, which can be combined with any of the embodiments already mentioned and those to be mentioned, unless contradicted, the joining element has a reinforcement, eg a reinforcement made of steel. In particular, the reinforcement includes fibers such as carbon, glass, stone, natural or plastic fibers (eg aramid fibers). The reinforcement extends in particular essentially between the top and bottom (in particular in order to absorb tensile forces essentially perpendicular to the top and bottom). The individual fibers run in particular in one piece continuously between the top and bottom of the joining element. Alternatively, the individual fibers do not run continuously, ie the individual fibers are shorter than the height of the joining element, in which case several cross-linked/interlaced individual fibers then run together continuously between the top and bottom. The joining element can thus be a "Fiber Reinforced Concrete" (FRC) or a "Carbon Prestressed Concrete" (CPC) component, for example. An additional reinforcement can extend in a longitudinal direction of the joining element (from front to back) essentially parallel to the top and bottom.

The following concrete slab construction according to the invention comprising at least one concrete slab, in particular at least one "Fiber Reinforced Concrete" (FRC) or "Carbon Prestressed Concrete" (CPC) slab, and at least one joining element (according to one of the above-mentioned embodiments) made of concrete, in particular made of FRC or CPC, for connecting concrete slabs and/or for fastening to a concrete slab as an intermediate product. Along a lateral perimeter of the concrete slab is between a top and a bottom of the concrete slab at least one bulge or indentation is present, the bulge or indentation in particular having two flanks tapering to an (optionally rounded but not necessarily pointed) tip or wedge-shaped flanks, in particular flat flanks, and the joining element being arranged on the lateral periphery of the concrete slab, wherein the indentation or bulge on one side of the joining element and the bulging or indentation of the concrete slab (roughly) face each other, and there is a filling material in a gap between the concrete slab and the joining element, the filling material being, for example, mortar or an adhesive. In particular, the concrete slab has reinforcement, for example reinforcement made of steel. The reinforcement can include fibers such as carbon, glass, stone, natural or plastic fibers (eg aramid fibers). In particular, the reinforcement is aligned substantially parallel to the top and bottom of the concrete slab. In particular, the reinforcement is aligned essentially perpendicularly to the left and right side of the joining element. The reinforcement serves in particular to absorb tensile forces essentially in the plane of the concrete slab (ie parallel to the top and bottom of the concrete slab). In particular, the reinforcement in the concrete slab is (roughly) perpendicular to a possible reinforcement in the joining element. The concrete slab can have additional reinforcement, which is approximately perpendicular to the above-mentioned reinforcement, with both being aligned essentially parallel to the top and bottom of the concrete slab (-> lattice-like reinforcement). There is also the following concrete slab construction according to the invention, comprising at least one concrete slab, in particular at least one "Fiber Reinforced Concrete" (FRC) or "Carbon Prestressed Concrete" (CPC) slab, and at least one joining element (according to one of the above-mentioned embodiments) made of concrete, in particular from FRC or CPC, proposed for connecting concrete slabs and/or for fastening in a concrete slab. The concrete slab has at least one recess, with a cross section of the recess between an upper side and an underside of the concrete slab on one (left, right, front or rear) side, and in particular also on another, in particular opposite (right, left, rear or front), side, (each) has at least one bulge or notch, wherein the bulge or notch in particular two to one

(Optionally rounded but not necessarily pointed) has tapering or wedge-shaped flanks (surfaces), in particular flat flanks, and wherein the joining element is arranged in the recess, with the respective notch or bulge of the joining element and the respective bulge or notch of the recess (Approximately) opposite one another, and with a filler or filling material being located in a space between the recess and the joining element, the filler or filling material being, for example, at least one fitting piece, such as a wedge, or (casting) mortar, (coarse) sand or an adhesive. The filling material forms in particular a permanent connection between the concrete slab and the Joining element, which is mainly loaded with pressure. Depending on the filling material, the connection is either non-detachable or detachable (again) (e.g. when using sand). In particular, the concrete slab has reinforcement, for example reinforcement made of steel. The reinforcement can include fibers such as carbon, glass, stone, natural or plastic fibers (eg aramid fibers). In particular, the reinforcement is aligned substantially parallel to the top and bottom of the concrete slab. In particular, the reinforcement is aligned essentially perpendicularly to the left and right side of the joining element. The reinforcement serves in particular to absorb tensile forces essentially in the plane of the concrete slab (ie parallel to the top and bottom of the concrete slab). In particular, the reinforcement in the concrete slab is (roughly) perpendicular to a possible reinforcement in the joining element. The concrete slab can have additional reinforcement, which is approximately perpendicular to the above-mentioned reinforcement, with both being aligned essentially parallel to the top and bottom of the concrete slab (-> lattice-like reinforcement).

According to an alternative according to the invention, the concrete slab construction comprises at least two concrete slabs, in particular at least two FRC or CBC slabs, and at least one joining element (according to one of the above-mentioned embodiments) made of concrete, in particular of FRC or CPC, for connecting concrete slabs and /or for attachment to a concrete slab, being along a lateral At least one bulge or indentation is present around the circumference of the concrete slabs between an upper side and an underside of the concrete slabs, with the bulge or indentation in particular having two or wedge-shaped flanks (surfaces) tapering to an (optionally rounded, not necessarily pointed) tip, in particular flat flanks, and wherein the joining element is arranged in a recess between the two concrete slabs, with the respective indentation or bulge of the joining element and the respective bulge or indentation of the concrete slabs (roughly) facing each other, and with a gap between the concrete slabs and the Joining element is a filler or a filling material, the filler or the filling material being, for example, at least one fitting, such as a wedge, or (grouting) mortar, (coarse) sand or an adhesive. In particular, the filling material forms a permanent connection between the concrete slabs and the joining element. Depending on the filling material, the connection is either non-detachable or detachable (again) (e.g. when using sand). In particular, the concrete slabs have reinforcement, for example reinforcement made of steel. The reinforcement can include fibers such as carbon, glass, stone, natural or plastic fibers (aramid fibers). The reinforcement is particularly

Substantially aligned parallel to the top and bottom of the concrete slabs. In particular, the reinforcement is aligned essentially perpendicularly to the left and right side of the joining element. In particular, the reinforcement in the two concrete slabs is essentially aligned. The reinforcement is used in particular to tensile forces in Substantially in the plane of the concrete slab (i.e. parallel to the top and bottom of the concrete slab). In particular, the reinforcement in the concrete slabs is perpendicular to a possible reinforcement in the joining element. The concrete slabs can have additional reinforcement, which is approximately perpendicular to the above-mentioned reinforcement, both of which are aligned essentially parallel to the top and bottom of the concrete slab (> lattice-like reinforcement).

As indicated above, indentations and bulges between the fastener and the concrete slab are approximately opposite, but do not touch or only marginally touch (see Fig. 10c), where the lower flanks of the indentations of the fastener and the lower flanks of the bulges touching the two concrete slabs to seal the space below only slightly). Consequently, the opposing indentations and bulges alone do not form a form fit. The positive and non-positive connection required for the concrete slab construction is only created by the filling material that has been introduced into the space and has hardened. It should also be noted that for the assembly of the concrete slab construction, the recess in the concrete slab must be large enough to be able to insert the joining element into the recess without the indentations and bulges on the joining element and the recess impeding this. In one embodiment of the concrete slab construction according to the invention, which can be combined with each of the embodiments already mentioned and those to be mentioned, unless contradicted, the recess is at least as wide as the width of the joining element or joining body .

In a further embodiment of the concrete slab construction according to the invention, which can be combined with any of the embodiments already mentioned and those to be mentioned, unless contradicted, the cutout runs continuously through the (respective) concrete slab or the cutout only partially into the (respective) concrete slab and thus forms a blind hole.

In a further embodiment of the concrete slab construction according to the invention, which can be combined with any of the embodiments already mentioned and those to be mentioned, provided they do not contradict this, the two flanks of the indentation or bulge of the joining element and the two flanks of the Bulge or indentation in or on the concrete slab (approximately) opposite, one flank of the bulge or indentation in or on the concrete slab emanating from an upper side of the concrete slab and the other flank emanating from a lower side of the concrete slab, these two flanks the bulge or indentation form an obtuse or acute angle cp ' or lock in . This angle cp' is equal or usually only approximately equal to the angle cp between the two flanks of the opposite indentation or bulge of the joining element. In particular, the angular difference cp*-cp is in the range of +/-20 ^° , in particular +/-10 ^° or only +/-5° . This difference in angle can be deliberately selected in order to influence the force transmission between the joining element and the concrete slab(s).

In a further embodiment of the concrete slab construction according to the invention, which can be combined with any of the embodiments already mentioned and those to be mentioned, provided this is not inconsistent with them, the joining element is an integral part of a concrete slab, in particular on an edge/lateral circumference the concrete slab formed in one piece with the concrete slab.

In a further embodiment of the concrete slab construction according to the invention, which can be combined with any of the embodiments already mentioned and those to be mentioned, unless in conflict with this, the at least one notch or bulge, in particular the two flanks, is located at least Part, in particular complete, within, in particular between the top and bottom, of the concrete slab(s). In a further embodiment of the concrete slab construction according to the invention, which can be combined with any of the embodiments already mentioned and those to be mentioned, unless in conflict with this, on or in the upper side and/or the underside of the concrete slab(s) , In particular (at least partially or completely) on the joining element, a connecting element, in particular a plate, strei fen- or hourglass-shaped connecting element, arranged, which with the concrete slab or. is connected to the two concrete slabs, for example screwed, dowelled or glued, the connecting element being particularly suitable for absorbing tensile forces (in the longitudinal direction). The connecting element can be made of metal, a fiber composite material or an FRC or CPC element. In particular, the connecting element on the concrete slab or the two concrete slabs will be laminated. Alternatively, the connecting element can be embedded in the concrete slab(s) and/or cast in concrete or mortared to the concrete slab(s).

In a further embodiment of the concrete slab construction according to the invention, which can be combined with any of the embodiments already mentioned and those to be mentioned, provided they do not conflict with this, a plurality of joining elements are arranged along a straight line at intervals, in particular at regular intervals, in ( or on) the concrete slab or between the concrete slabs. In a further embodiment of the concrete slab construction according to the invention, which can be combined with any of the embodiments already mentioned and those to be mentioned, provided they do not contradict this, several joining elements are spaced along a serpentine line or a zigzag line, in particular at regular intervals , in (or on) the concrete slab or between the concrete slabs, the serpentine line being composed in particular of curved sections and the zigzag line being composed in particular of straight sections.

In a further embodiment of the concrete slab construction according to the invention, which can be combined with any of the embodiments already mentioned and those to be mentioned, unless in conflict with this, the joining elements are arranged alternately essentially orthogonally with respect to their longest dimension.

In a further embodiment of the concrete slab construction according to the invention, which can be combined with any of the embodiments already mentioned and those to be mentioned, unless this contradicts this, both joining bodies with and without an extension in the concrete slab or arranged between the concrete slabs, in particular in a regular pattern, in particular are alternately arranged joining body with and without extension.

In a further embodiment of the concrete slab construction according to the invention, which can be combined with any of the embodiments already mentioned and those to be mentioned, unless in conflict with this, the joining element is located between two spaced stacked (i.e. parallel hori zontal one above the other or arranged vertically next to each other) concrete slabs, wherein the two concrete slabs are in particular connected to one another or supported on one another by means of the joining element.

In a further embodiment of the concrete slab construction according to the invention, which can be combined with any of the embodiments already mentioned and those to be mentioned, unless in conflict with them, the two concrete slabs stacked at a distance (in the direction of their greatest extent) are arranged offset to one another .

In a further embodiment of the concrete slab construction according to the invention, which can be combined with any of the embodiments already mentioned and those to be mentioned, unless in conflict with them, some, in particular a majority (>50%), of the recesses do not run completely continuously through the concrete slab or through the concrete slabs ( i .e . only partially extending into the concrete slab ) , and that some , especially a minority (< 50%) , of the recesses go completely through the concrete slab or the concrete slabs run, with at least one non-continuous recess being located in particular between each two continuous recesses.

In a further embodiment of the concrete slab construction according to the invention, which can be combined with any of the embodiments already mentioned and those to be mentioned, provided this does not contradict this, the concrete slab construction is a concrete ceiling element or a concrete ceiling comprising several concrete ceiling elements or a bridge element or a concrete bridge comprising several bridge elements.

In all of the above-mentioned embodiments of a concrete slab construction according to the invention, the joining element preferably has only indentations and the counterpart on one side or in a recess of the concrete slab only bulges, because this results in better force transmission from the joining element to the concrete slab. If, on the other hand, the joining element only has bulges and the counterpart on or in the concrete slab only has indentations, it can happen under heavy loads that a crack forms in the concrete slab, starting from the tip of the indentation. The joining element preferably has indentations on two opposite sides on . Correspondingly, the recess in the concrete slab has bulges on two opposite sides. The two flanks of the indentation and bulges preferably enclose an obtuse angle, the angle being in particular in a range between 90° and 130°.

According to a further aspect of the present invention, a method for producing a concrete slab construction according to the invention as an intermediate product is proposed. The method according to the invention comprises the following steps:

- providing at least one joining element (according to one of the above-mentioned embodiments);

- Providing at least one concrete slab, in particular at least one ERG or CBC slab, with at least one bulge or indentation being present along a lateral circumference of the concrete slab between an upper side and an underside of the concrete slab, the bulge or indentation being in particular two to one (optionally rounded not necessarily pointed) tip tapering or . has wedge-shaped flanks, in particular flat flanks;

arranging the joining element on the lateral periphery of the concrete slab, with the indentation or bulge on one side of the joining element being (approximately) opposite the bulge or indentation of the concrete slab; - Filling an intermediate space between the concrete slab and the joining element with a filling material, the filling material being, for example, mortar or an adhesive.

According to a further aspect of the present invention, a method for producing a concrete slab construction according to the invention is proposed. The method according to the invention comprises the following steps:

- Providing at least one concrete slab, in particular at least one FRC or CBC slab, the concrete slab having at least one recess, a cross section of the recess between a top and a bottom of the concrete slab on a (left/right/front/rear) Side and optionally on another (opposite right/left/rear/front) side je has at least one bulge or notch, the bulge or notch in particular two to one

(optionally rounded not necessarily pointed) tip tapering or . has wedge-shaped flanks (surfaces), in particular flat flanks, with the recess in particular running continuously through the concrete slab or running only partially into the concrete slab;

- Arranging the joining element in the recess so that the respective notch or bulge of the Joining element and the respective bulge or indentation of the recess (roughly) face each other;

- Filling of a space between the recess and the joining element with a filler or a filling material, wherein the filler or the filling material is, for example, at least one fitting, such as a wedge, or mortar, sand or an adhesive.

The filling material should in particular form a permanent connection between the concrete slab and the joining element. Depending on the filling material, the connection is either non-detachable or detachable (again) (e.g. when using sand). In particular, the filling material should be pressure-resistant (when it has hardened) because it mainly takes on compressive forces (i.e. it should not be able to be compressed in the space under pressure in such a way that the filling material yields too much and it shifts or its shape or volume changes significantly - because the filling material is intended to forward or transmit the compressive forces to the concrete slab(s) connected to the joining element).

In one embodiment of the method according to the invention, the joining element is arranged in the recess by inserting the joining element into the recess in the direction (essentially perpendicular) to an upper side or an underside of the concrete slab or by pushing the joining element into the recess on a lateral periphery of the Concrete slab in the direction parallel to the top or bottom of the concrete slab. According to an alternative according to the invention, the method for producing a concrete slab structure according to the invention comprises the following steps:

- Provision of at least two concrete slabs, in particular at least two FRC or CBC slabs, with at least one bulge or at least one indentation being present along a lateral circumference of the concrete slabs between an upper side and an underside of the concrete slabs, the bulge or indentation in particular two to one

(optionally rounded but not necessarily pointed) tip tapering or wedge-shaped flanks (surfaces), in particular flat flanks;

- Arranging the joining element between the two concrete slabs in a recess, so that the respective indentation or bulge of the joining element and the respective bulge or indentation of the concrete slabs (roughly) face each other;

- Filling of a space between the concrete slabs and the joining element with a filler or a filling material, the filler or the filling material being, for example, at least one fitting, such as a wedge, mortar, or sand or an adhesive.

The filling material should in particular form a permanent connection between the concrete slab and the joining element. Depending on the filling material, the connection is either non-detachable or detachable (again) (e.g. when using sand). In particular, the filling material should be pressure-resistant (when it has hardened) because it primarily absorbs compressive forces.

In one embodiment of the method according to the invention, the joining element is arranged between the two concrete slabs by the following steps:

- arranging the two concrete slabs on a plane;

- Insertion of the joining element in the recess between the two concrete slabs;

- Bringing the two concrete slabs together in the direction parallel to the plane until there is a distance in a range of 1 cm to 5 cm between the respective bulge or indentation of the concrete slabs and the respective indentation or bulge of the joining element.

Alternatively, the joining element is arranged between the two concrete slabs using the following steps:

- Arranging the two concrete slabs on a plane at a distance which is less than the widest dimension of the joint body or. of the joining element from the left to the right side;

- Insertion of the joining element in the recess between the j eweilige bulge or notch of the two concrete slabs in a direction parallel to the top or. Underside of the two concrete slabs.

The liability between tween the joining element and the concrete slabs can be improved by the contact surfaces between the concrete slabs and the joining element can be roughened, eg by means of sandblasting.

In one embodiment of the method according to the invention, which can be combined with any of the embodiments already mentioned and those to be mentioned, unless contradicted, a filler or a quantity of Filling material introduced into the gap in such a way that inaccuracies in the shape and/or dimensions of the concrete slabs and the joining element, in particular the notches and bulges and their arrangement, i.e. deviations from their desired shape or size, are (largely) compensated for. This means that the components are manufactured with large tolerances, i.e. with a lot of play to "undersize", whereby the loose fit is then filled with the filling material, such as mortar.

In a further embodiment of the method according to the invention, which can be combined with any of the embodiments already mentioned and those to be mentioned, unless in conflict with them, the method comprises the following further step:

- Fastening a connecting element, in particular a plate, strip or hourglass-shaped connecting element, on or in the top and / or bottom of the concrete slab (s), especially on the Joining element (1), for example by means of one or more fasteners, such as screws, or by means of an adhesive.

The connecting element can be made of metal or a fiber composite material. In particular, the connecting element on the concrete slab or the two concrete slabs will be laminated. Alternatively, the connecting element can be concreted into the concrete slab(s) or mortared to the concrete slab(s).

In a further embodiment of the method according to the invention, which can be combined with any of the embodiments already mentioned and those to be mentioned, unless contradicted, several joining elements are spaced along a straight line, in particular at regular intervals, in (or at) the concrete slab or arranged between the concrete slabs.

In a further embodiment of the method according to the invention, which can be combined with any of the embodiments already mentioned and those to be mentioned, unless contradicted, several joining elements are spaced along a serpentine line or a zigzag line, in particular at regular intervals , arranged in (or on) the concrete slab or between the concrete slabs, the serpentine line being composed in particular of curved sections and the zigzag line being composed in particular of straight sections. In a further embodiment of the method according to the invention, which can be combined with any of the embodiments already mentioned and those to be mentioned, provided they do not contradict this, the joining elements are arranged alternately essentially orthogonally with respect to their longest dimension.

In a further embodiment of the method according to the invention, which can be combined with each of the embodiments already mentioned and those to be mentioned, unless in conflict with this, joining elements are used both with and without an extension in the concrete slab or arranged between the concrete slabs, in particular in a regular pattern. In particular, joining elements are alternately with and without extension in the concrete slab or. placed between the concrete slabs.

In a further embodiment of the method according to the invention, which can be combined with any of the embodiments already mentioned and those to be mentioned, unless in conflict with them, at least one joining element is arranged between two concrete slabs that are stacked (on top of one another or next to one another) at a distance and connected to at least one of the concrete slabs so that the concrete slabs are connected or supported on each other. In a further embodiment of the method according to the invention, which can be combined with any of the embodiments already mentioned and those to be mentioned, unless in conflict with this, the two concrete slabs stacked at a distance from one another are arranged in an offset manner (in the direction of their greatest extent ) .

In a further embodiment of the method according to the invention, which can be combined with each of the embodiments already mentioned and those to be mentioned, some, in particular a majority, of the recesses do not run completely through the concrete slab or the concrete slabs, and some, especially a minority, of the recesses run completely through the concrete slab or the concrete slabs, in particular between each two continuous recesses at least one non-continuous recess is to be arranged in each case.

According to a further aspect of the present invention, use of the joining element in which the upper flank and the lower flank are of different lengths is specified. It is then proposed to use the joining element to absorb forces on the joining element and to transfer forces to the concrete slab(s) connected to the joining element, with the shorter of the two flanks mainly being used to absorb and transfer compressive forces and the longer of the both flanks mainly for absorbing and passing on tensile forces. According to a further aspect of the present invention, a use of the concrete slab construction according to the invention is specified. It is then proposed to use the concrete slab construction according to the invention as part of the following structures:

- ERG or CPC supporting structures of buildings, such as wall/ceiling connections, roof structures, wall structures, (suspended) ceilings, stairs, wall/wall connections in building cores also for seismic reinforcement, basements in the ground, hollow columns, entire wall systems, self-supporting balconies, tower structures, staircases, folded structures;

- Entire simple buildings, such as community utility buildings, vehicle shelters, electrical distribution boxes, container shelters, platform roofs, tram and bus shelters;

- a concrete pavement or bridge for roads, railways, pedestrians and cyclists, pipelines, aqueducts;

- Structures in civil engineering such as retaining walls, ramp structures, shelters;

- load-bearing components such as bending beams in T, H and U shapes or box girders;

- Supporting structures in shipbuilding. According to a further aspect of the present invention, a method for producing a joining element is proposed. The method according to the invention comprises the following steps:

- Providing a concrete slab, in particular an FRC or CBC slab, with a top and a bottom and with a length dimension and a width dimension;

- Milling notches in the upper side and oppositely on the underside of the concrete slab in the direction of the width extension, in particular at regular intervals;

- Cutting, in particular sawing, the concrete slab between or in the notches, in particular between adjacent notches or between several adjacent notches, more particularly at the beginning and/or at the end of the notches, in the direction of the widthwise extension and in the direction of the lengthwise extension, by a large number to obtain from individual joining elements.

Alternatively, the method according to the invention comprises the following steps:

- Providing a concrete cylinder with a cylinder axis, in particular an ERG or CPC cylinder, in particular with a round, oval/elliptical or polygonal/polygon-shaped (i.e. prism-shaped cylinder) cross-section;

- Milling notches in a part of the concrete cylinder and in an opposite part of the circumference of the concrete cylinder or in the entire circumference of the concrete cylinder, in particular perpendicular to the cylinder axis, in particular at regular intervals;

- Cutting, in particular sawing, the concrete cylinder between or in the notches, in particular between adjacent notches or between several adjacent notches, more particularly at the beginning and/or at the end of the notches, perpendicular to the cylinder axis (in slices) by a large number of to obtain individual joining elements.

In one embodiment according to the invention, the method further comprises at least one of the following steps:

- Surface treatment of the individual joining elements, in particular by means of sand or water blasting, roughing or coating, in particular for roughening a surface of the individual joining elements;

- Insertion of reinforcement in the concrete slab or the concrete cylinder during the manufacture of the concrete slab or the concrete cylinder in the direction of linear expansion or the cylinder axis ;

Face milling of a part of the circumference of the concrete cylinder, in particular before milling indentations;

- Forming of different notches as part of notch milling, e .g . B. by using differently shaped milling heads to form different parts of the fasteners, such as indentations, bulges, and projections; - Grinding or turning of the individual joining elements, in particular for further shaping.

Furthermore, a method for producing a joining element is proposed with the step:

- Cutting out several joining elements (1) from a concrete slab, in particular an FRC or CPC slab, by means of a high-pressure water jet and/or a

Milling cutter and / or a jigsaw or circular saw and / or a punching tool, this being done in particular by a CNC machine (Computerized Numerical Control).

Finally, a method for producing a concrete slab for a concrete slab construction is proposed with at least one of the two steps:

- Cutting out a joining element (1) from the concrete slab, in particular an FRC or CPC slab;

- Cutting the recess out of the concrete slab, in particular an FRC or CPC slab, using a high-pressure water jet and/or a

It should be expressly noted that combinations of the above variants are possible, which in turn to more specific execution variants of the present

lead invention.

BRIEF DESCRIPTION OF THE DRAWINGS

Non-limiting embodiments of the present

Invention are explained in more detail below with reference to figures. Show it:

1a) shows a schematic cross section through a first exemplary embodiment of a joining element for the invention;

1b) shows a schematic cross section through a second exemplary embodiment of a joining element for the invention;

1c) shows a schematic cross section through a third exemplary embodiment of a joining element for the invention;

1d) shows a schematic cross section through a fourth exemplary embodiment of a joining element for the invention;

le) shows a schematic cross section through a fifth exemplary embodiment of a joining element for the invention;

1f) shows a schematic cross section through a sixth exemplary embodiment of a joining element for the invention; 2a) shows a schematic cross section through a seventh exemplary embodiment of a joining element for the invention;

2b) shows a schematic cross section through an eighth exemplary embodiment of a joining element for the invention;

3a) shows a schematic cross section through a ninth exemplary embodiment of a joining element for the invention with an extension on the joining element according to FIG. 1b) ;

3b) shows a schematic cross section through a tenth exemplary embodiment of a joining element for the invention with an extension on the joining element according to FIG. Id) ; 4a) shows a schematic cross section through an eleventh exemplary embodiment of a joining element for the invention with an extension between two joining elements according to FIG. 1b);

4b) shows a schematic cross section through a twelfth exemplary embodiment of a joining element for the invention with an extension between two joining elements according to FIG. 1d);

5a) shows a schematic cross section through a thirteenth embodiment of a joining element for the invention with two notches on both sides;

Fig. 5b) is a schematic cross section through a fourteenth embodiment of a Joining element for the invention with two bulges on both sides;

FIG. 6a) shows a schematic perspective view of the second exemplary embodiment of a joining element for the invention from FIG. 1b);

FIG. 6b) shows a schematic perspective view of the fourth exemplary embodiment of a joining element for the invention from FIG. 1d);

FIG. 6c) shows a schematic perspective view of the eighth exemplary embodiment of a joining element for the invention from FIG. 2b);

FIG. 6d) shows a schematic perspective view of the seventh exemplary embodiment of a joining element for the invention from FIG. 2a); 7a) shows a schematic cross section through a first exemplary embodiment of a concrete slab construction according to the invention;

7b) shows a schematic cross section through a second exemplary embodiment of a concrete slab construction according to the invention;

7c) shows a schematic cross section through a third exemplary embodiment of a concrete slab construction according to the invention;

8a) shows a schematic cross section through a fourth exemplary embodiment of a concrete slab construction according to the invention; Fig. 8b) a schematic cross section through an alternative fourth exemplary embodiment of a concrete slab construction according to the invention;

Fig. 8c) a schematic cross section through a fifth exemplary embodiment of a concrete slab construction according to the invention;

Fig. 9a) a schematic plan view of a sixth embodiment of a concrete slab construction according to the invention;

Fig. 9b) a schematic plan view of a seventh embodiment of a concrete slab construction according to the invention;

Fig. 9c) a schematic plan view of an eighth exemplary embodiment of a concrete slab construction according to the invention;

Fig. 9d) a schematic plan view of a ninth embodiment of a concrete slab construction according to the invention;

Fig. 9e) a schematic plan view of a tenth embodiment of a concrete slab construction according to the invention;

Fig. 9'a) a schematic sectional view along line AA' in FIG. 9'b) of an alternative sixth embodiment of a concrete slab construction according to the invention;

Fig. 9'b) shows a schematic sectional view along line BB' in FIG. 9'a) of the exemplary embodiment as in FIG. 9'a); Fig. 9'c) a schematic sectional view along the

Route C-C in Fig. 9'b) of the embodiment as in Fig. 9'a);

10a) shows a schematic cross section through an eleventh exemplary embodiment of a concrete slab construction according to the invention;

10b) shows a schematic cross section through a twelfth embodiment of a concrete slab construction according to the invention;

10c) shows a schematic cross section through a thirteenth exemplary embodiment of a concrete slab construction according to the invention;

10d) shows a schematic cross section through a fourteenth exemplary embodiment of a concrete slab construction according to the invention;

11a) shows a schematic perspective view of a fifteenth embodiment of a concrete slab construction according to the invention;

11b) shows a schematic perspective view of a sixteenth embodiment of a concrete slab construction according to the invention;

11c) shows a schematic perspective view of an alternative fifteenth embodiment of a concrete slab construction according to the invention;

Fig. lld) a schematic perspective view of another alternative fifteenth From exemplary embodiment of an inventive concrete slab construction;

Fig. Ile) is a schematic perspective view of an alternative sixteenth embodiment of a concrete slab construction according to the invention;

Fig. l l f) a schematic perspective view of another alternative sixteenth embodiment of a concrete slab construction according to the invention; and

Fig. 12a-g) schematic cross sections through a seventeenth to twenty-third exemplary embodiment of a concrete slab construction according to the invention.

In the figures, the same reference symbols stand for the same elements.

DETAILED DESCRIPTION OF THE INVENTION

In Fig. 1 shows various exemplary embodiments of joining elements 1 in cross section, which can be used for a concrete slab construction according to the invention. The joining elements 1 are made of concrete, in particular with reinforcement 13 . The joining elements 1 are then designed, for example, as ERG or, in particular, as CPC components. 1a) shows a profile of a first exemplary embodiment of a joining element 1 with a joining body 3, which has a notch 8, 8' on the left-hand side 6 and on the right-hand side 7. In principle, the notch 8' on the right-hand side 7 is optional--this is indicated by the dotted line on the right-hand side 7 (as is also the case in the other figures 1b)-1f) & 2-6). The two notches 8, 8' each have an upper flank 11 and a lower flank 11', which converge in a wedge shape to form a tip 10 and form an obtuse angle cp. The profile or the cross section of the joining element 1, which here consists only of the joining body 3, is mirror-symmetrical both with respect to the vertical central axis and with respect to the horizontal central axis. This means that the cross section is point symmetrical, since all four flanks are of the same length. Reinforcement 13 is placed in the joining element 1 in the direction of the vertical central axis between the upper side 4 and the lower side 5 . The reinforcement 13 ensures, in particular, that the joining element 1 can absorb tensile forces which act on the joining element 1 essentially perpendicularly to the top and bottom. Such vertical external forces with a horizontal force component act through the two notches 8, 8' on the concrete slab into which the joining element 1 is inserted, or the concrete slabs which the joining element 1 joins (see FIGS. 7 ff). In this case, vertical external forces are directed towards the horizontal central axis (resulting in a Compression effect of the notches on the concrete slab (s) leads).

FIG. 1b) shows a second, slightly modified embodiment of a joining element 1 from FIG. The cross section of the joining element 1 remains mirror-symmetrical with respect to the vertical central axis, but is no longer mirror-symmetrical with respect to the horizontal central axis (and thus also no longer point-symmetrical). By changing the length of the flanks 11, 11', the angle cp can be adjusted in such a way that when the joining element 1 is subject to an external load, the flow of force runs through the joining element 1 in the desired manner.

1c) shows a profile of a third exemplary embodiment of a joining element 1, which has a bulge 9, 9' on the left-hand side 6 and on the right-hand side 7 instead of indentations. This shaping of the joining element 1 directs vertical external forces in the direction of the top and bottom of the concrete slab or slabs into which the joining element 1 is inserted or joined.

FIG. 1d) shows a profile of a fourth, slightly modified embodiment of a joining element 1 from FIG. 1c), in which the upper flank 11 is somewhat shorter than the lower flank 11′, as a result of which the angle cp becomes smaller. this leads to to a changed force flow through the joining element 1 in the event of an external load.

Fig. le) shows a profile of a fifth embodiment of a joining element 1, which instead of two notches or bulges on the left side 6 has a notch 8 and on the right side 7 has a bulge 9'. All flanks 11, 11' of the notch 8 and the bulge 9' are of the same length here. Due to this shape of the joining element 1, vertical external forces are directed on the left-hand side 6 in the direction of the horizontal center axis and on the right-hand side 7 in the direction of the top and bottom of the concrete slab or slabs into which the joining element 1 is or is inserted. which joins the joining element 1 together, passed.

Fig. If) shows in profile a sixth, slightly modified embodiment of a joining element 1 from Fig. le), in which the upper flank 11 is somewhat shorter than the lower flank 11 ', whereby the angle cp is smaller. This leads to a changed flow of forces through the joining element 1 in the event of an external load.

The joining elements according to FIG. 1 can be made, for example, from a concrete slab, in particular an FRC or CPC slab, by milling notches in the upper side and oppositely on the underside of the concrete slab and then Cutting the concrete slab into individual joining elements are produced (as stated above).

2a) shows a profile of a seventh, slightly modified embodiment of a joining element 1 from FIG. The flanks 11, 11' of the two indentations 8, 8' are all of the same length here. This joining element 1 can, for example, be rotationally symmetrical about the vertical central axis and thus an hourglass-shaped body (see FIG. 6d)).

FIG. 2b) shows the profile of an eighth, slightly modified embodiment of a joining element 1 from FIG. 2a), in which the upper flank 11 is somewhat shorter than the lower flank 11', as a result of which the angle cp becomes smaller. This leads to a changed flow of forces through the joining element 1 in the event of an external load.

3a) shows a profile of a ninth exemplary embodiment of a joining element 1, in which an extension 12 is attached to the upper side 4 of the joining body 3 (according to FIG. 1b). The joining body 3 and the extension 12 are in one piece (ie they consist of one piece or are formed integrally) and together form the joining element 1 as a unit. The extension 12 can alternatively also be attached to the underside 5 of the joining body 3 . The extension 12 as Coupling element can be used for coupling to another component, eg for hanging concrete slabs in/between which the joining element is inserted. However, it can also serve as a support for supporting concrete slabs in/between which the joining element is inserted. The joining body 3 can have any form, for example as shown in FIG. 1 or 2. 3b) accordingly shows a profile of a tenth exemplary embodiment of a joining element 1, in which an extension 12' is attached to the underside 5 of the joining body 3 (according to FIG. 1d)). It is also possible for an extension 12, 12' to be attached both to the upper side 4 of the joining body 3 and to the lower side 5, as is the case in FIGS. 8b) & 8c) by way of example. The length of the two extensions 12, 12' can be different.

4a) shows a profile of an eleventh exemplary embodiment of a joining element 1, in which an extension 12 is inserted between two identical joining bodies 3, 3' (according to FIG. 1b). Another joining body 3' was integrally attached to the free end of the extension 12 on the joining element 1 with the extension 12 according to FIG. The joining body 3 can have any form, for example as shown in FIG. 1 or 2. 4b) accordingly shows a twelfth exemplary embodiment of a joining element 1 in profile, in which the joining bodies 3, 3' according to FIG. 1d) are integrally joined together by the extension 12. There can also be differently shaped joining bodies 3, 3' at the two ends of the joining element 1. 5a) shows a profile of a thirteenth exemplary embodiment of a joining element 1, in which the joining body 3 has a further notch 8'', 8''' between the upper side 4 and the lower side 5 on the left side 6 and the right side 7 . 5b) shows a profile of a fourteenth exemplary embodiment of a joining element 1, in which the joining body 3 has two bulges 9, 9'' and 9'', 9''' on both sides.

Fig. 6a) shows a perspective view of the second

Exemplary embodiment of a joining element 1 from FIG. 1b) with two indentations 8, 8'. The dimensions of the joining element 1 can be seen here as an example, in particular it is shown how the joining element 1 expands in the longitudinal direction. Typically, the height H of the joining body 3 (between the top 4 and the bottom 5) is in a range from 2 cm to 10 cm, the width B of the joining body 3 (between the left side 6 and the right side 7) is in a range from 2 cm to 10 cm and the length L of the joining element 1 is in a range from 5 cm to 20 m, rather up to 1 m, most likely up to 50 cm. In any case, they are dimensioned in such a way that they are suitable for joining commercial concrete slabs, which are often available as semi-finished products. The length ratio of the upper, shorter flank 11 to the lower, longer flank 11' is in a range from 1:16 to 1:1 and the angle cp enclosed by the two n flanks 11, 11' can be an obtuse angle (90 °<<p<l 80 ° ) or an acute angle (0°<<p<90 ^o ), for example in a range of 60° to 160°. An upper extension 12 on the joining body 3 is drawn in dashed lines in FIG. 6a), both of which together form the joining element 1 in one piece.

FIG. 6b) shows a perspective view of the fourth exemplary embodiment of a joining element according to the invention from FIG. 1d) with two bulges 9, 9'. In FIG. 6 b ), a lower extension 12 ′ on the joining body 3 is drawn in with a broken line, both of which together form the joining element 1 in one piece.

Fig. 6c) shows a perspective view of the eighth embodiment of a joining element 1 from Fig. 2b) with two notches 8, 8' and rounded edges along the top and bottom 4, 5.

FIG. 6d) shows a perspective view of the seventh exemplary embodiment of a joining element according to the invention from FIG. 2a). This joining element 1 is rotationally symmetrical about the vertical central axis and has an hourglass-shaped body with a circumferential notch 8. The top and bottom 4, 5 in the illustration of FIG. 6d) appear flat, but the top and bottom edges can also be partial or be completely rounded, so that the top and bottom 4, 5, for example, oval or (semicircular) are shaped around. Any combination of the joining bodies 3, 3' and extensions 12, 12' shown in FIGS. 1 to 6 is possible in order to form joining elements.

The joining elements according to Fig. 1 to 6c) can, for example, be produced from a concrete slab, in particular an FRC or CBC slab, by milling notches in the upper side and oppositely on the underside of the concrete slab and then dividing the concrete slab into individual joining elements (as mentioned above) . Rotationally symmetrical joining elements, for example according to Fig. 6d), can be produced from a concrete cylinder, in particular an FRC or CPC cylinder, by milling notches along the concrete cylinder and then "slicing" the concrete cylinder into individual joining elements (as stated above).

7a) shows a cross section through a first exemplary embodiment of a concrete slab construction 14 according to the invention, consisting of two concrete slabs 2, 2′, which lie in one plane, and a joining element 1 according to the invention, which is arranged between the two concrete slabs 2, 2′. The joining element 1 has a notch 8, 8' on the left and right sides 6, 7 here. Correspondingly, the two concrete slabs 2, 2' have bulges 20, 20' along the (circumferential) side that faces the joining element 1.

The gap 24 between the indentations 8, 8' of the joining element 1 and the bulges 20, 20' of the two Concrete slabs 2, 2 'is filled with a filling material 25 such as (grout) mortar, (coarse) sand or an adhesive. Alternatively, one or more fitting piece(s), such as a wedge(s), can be used as a filler in the gap 24 as far as possible with a form fit. The filling material 25 is in particular pressure-resistant, in particular when it has hardened in the intermediate space 24 . In particular, FRC or CPC slabs are used as concrete slabs, with the reinforcement 26, for example in the form of fibers, in particular carbon fibers, being aligned (horizontally) in the plane of the concrete slabs 2, 2' in the direction of the joining element 1. A reinforcement 13 in the joining element 1, on the other hand, is aligned perpendicular to the reinforcement 26 in the concrete slabs 2, 2'. Above and/or below the joining element 1, a (tensile) connecting element 27 (shown in dashed lines) can optionally also be fastened to the surface of the concrete slabs 2, 2'. In order to insert the joining element 1 into a recess 15 in a concrete slab 2, the width B' of the recess must be at least as large as the width B of the joining element 1, so that the joining element 1 can be seen from above (see vertical arrow pointing downwards in Fig. 7a ) ) or can be introduced into the recess 15 from below. In the case of two separate concrete slabs 2, 2 'as here, the joining element 1 can be placed between the two concrete slabs 2, 2' during assembly, which are then pushed together against each other in the direction of the joining element 1 until the desired gap 24 for filling with Filling material 25 is still available or as far as the geometry of the joining element 1 allows pushing together (pushing the two together Concrete slabs 2, 2' in the horizontal direction of the arrow in Fig.

7a) shown). To simplify assembly, for example, the joining element 1 can be fastened to the bulge 20, 20' of one concrete slab 2, 2', e.g. by means of an adhesive or mortar (see Fig. 10d, hatched fastening area 28 top right).

Alternatively, however, the joining element 1 can also, as described above, be inserted vertically into the intermediate space 24 from above or below.

Fig. 7b) shows a cross section through a second

Embodiment of an inventive concrete slab structure 14, in which the two

Notches 8, 8' of the joining element 1 are not entirely identical due to manufacturing tolerances. The two bulges 20, 20' of the two concrete slabs 2, 2' are also not identical and the tip 10 of the bulge of the left concrete slab 2 is not at the same height as the tip 10 of the left notch 8 of the joining element 1, also due to inaccuracies in the Production of the concrete slab (or the joining element) . These inaccuracies in the shape and / or dimensions of the concrete slabs 2, 2 'and the joining element 1, in particular the notches 8, 8' and bulges 20, 20 'and their arrangement, ie deviations from their target shape or size, can by the filling material 25, such as mortar, are largely compensated. This means that the components can be manufactured to "undersize" with large tolerances, i.e. with a lot of play are, in which case the loose fit is filled by the filler material 25.

7c) shows a cross section through a third exemplary embodiment of a concrete slab construction 14 according to the invention, in which, as an alternative (to FIGS. 7a) & 7b)), a joining element 1 with two bulges 9, 9' is used, which have corresponding indentations 21, 21'. facing the concrete slabs.

It is expressly pointed out again that the indentations or bulges of the joining element do not have to be of the same shape as the corresponding bulges and indentations of the concrete slab(s) and in particular that they do not have to interlock positively, but that differences in shape and/or dimensions are caused by the Filling material to be accommodated in the space.

Fig. 8a) shows a cross section through a fourth exemplary embodiment of a concrete slab construction 14 according to the invention, in which the recess 15 between the two concrete slabs 2, 2' does not go completely from the top to the underside of the concrete slabs 2, 2', but rather a blind hole in the assembled state forms. In this way, in particular, the filling material 25 (e.g. also sand) is held in the intermediate space 25 and prevented from escaping through a lower opening of the Gap 25 can occur. Such a lower opening with a continuous recess 15 could be closed (temporarily or permanently) with a cover (see, for example, FIG. 10c)), for example also by means of a connecting element 27. Furthermore, in FIG. 8a) an optional (tensile) connecting element 27 is dashed drawn in, which is embedded under the joining element 1 in the concrete slabs 2, 2', for example mortared.

FIG. 8 b ) shows a cross section through an alternative fourth exemplary embodiment of a concrete slab construction 14 according to the invention, in which a joining element 1 with two notches 8 , 8 ′ is inserted in a recess 15 in a concrete slab 2 . The joining element 1 was introduced here from above (would also be possible from below) into the recess 15 (in the direction of the arrow shown). For this purpose, the narrowest point (width B′) of the recess 15 must be at least as wide as the width B of the joining element 1 so that it can be inserted completely into the recess 15 where the remaining intermediate space 24 is then filled with filling material 25 . In this example, an extension 12 is attached to the top 4 of the joining body 3 . Alternatively or additionally, an extension 12' could also be attached to the underside 5 (indicated by the dotted lines).

Fig. 8c) shows a cross section through a fifth

Embodiment of an inventive

Concrete slab structure 14, in which a joining element 1 with two bulges 9, 9 'in a recess 15 of a concrete slab 2 is inserted. The joining element 1 was introduced here from above (would also be possible from below) into the recess 15 (in the direction of the arrow shown). For this purpose, the recess 15 must be wider than the width B of the joining element 1 so that the latter can be inserted completely into the recess 15, where the remaining intermediate space 24 is then filled with filling material 25. In this example, an extension 12 is attached to the top 4 of the joining body 3 . Alternatively or additionally, an extension 12' could also be attached to the underside 5 (indicated by the dotted lines).

In all of the exemplary embodiments illustrated in FIGS. 7a)-c) & 8a)-c), the joining elements 1 are positioned vertically in or between the concrete slabs 2, 2'. However, it is also conceivable that the joining element is arranged (slightly) inclined in the concrete slab, or that the two concrete slabs are each arranged (slightly) inclined to the joining element (whereby the inclination only arises as a result of a load or e.g. then disappears). The inclination of the joining element can be deliberately selected in order to influence the force transmission between the joining element and the concrete slab(s).

9a) shows a plan view of a sixth embodiment of a concrete slab construction 14 according to the invention, in which several joining elements 1 are used to join two concrete slabs 2, 2' become. In this case, the straight sides of the two concrete slabs 2, 2' are joined together, there being recesses 15 at regular intervals along the sides of the two concrete slabs 2, 2', into which the joining elements 1 are inserted. Alternatively, a single long joining element can also be inserted into a correspondingly long recess 15 between the two concrete slabs 2, 2' (shown in dashed lines).

9b) shows a plan view of a seventh embodiment of a concrete slab construction 14 according to the invention, in which several joining elements 1 are used to join two concrete slabs 2, 2'. In order to increase the stability of the concrete slab construction 14 perpendicular to the line along which the two concrete slabs 2, 2' are joined, this line is designed as a wavy line along which the joining elements 1 are inserted at regular intervals. As a result, the alignment of the joining elements 1 is slightly different, so that tensile and compressive forces on the two concrete slabs 2, 2' in the plane of the slab and also perpendicular thereto can be better distributed by the joining elements 1 over the entire concrete slab structure 14. In Fig. 9b) the recess 15 extends along the entire serpentine line.

Fig. 9c) shows a plan view of an eighth embodiment of a concrete slab construction 14 according to the invention, in which the joining elements 1 are alternatively inserted along a zigzag line at regular intervals instead of along a serpentine line. In this case, for example, small rotationally symmetrical (eg hourglass-shaped) joining elements 1 and those with an (approximately) square outline are used in the narrow peaks of the zigzag line. Alternatively, instead of the four drawn-in elongated joining elements 1 with a rectangular outline, a large number of smaller eg rotationally symmetrical (hourglass-shaped) joining elements 1 could be used (similar to riveting two metal sheets together—see eg FIG. 9e)). In Fig. 9c) the recess 15 also extends along the entire zigzag line.

Fig. 9d) shows a top view of a ninth exemplary embodiment of a concrete slab construction 14 according to the invention, in which the joining elements 1 are again inserted along a zigzag line at regular intervals, with the recess 15 not extending along the entire zigzag line, but one recess in each case 15 per sections of the zigzag line. In this exemplary embodiment, instead of small joining elements 1 (with a round/square outline) in the narrow tips of the zigzag-shaped line (tensile) connecting elements 27, e.g. with an hourglass-shaped outline, are embedded in the surface of the two concrete slabs 2, 2', eg mortared. It should be noted that these connecting elements 27 are not arranged via a joining element, but in recesses 15 in the surfaces of the two concrete slabs 2, 2'. The flat hourglass-shaped connecting elements 27 fit into the somewhat larger hourglass-shaped recesses in the surfaces of the two concrete slabs 2, 2' and thus form strong connections between the two concrete slabs 2, 2' (in the direction of in Fig. 9d) horizontally Lying central axes of the connecting elements 27). In the event of horizontal compression and compression forces on the concrete slabs 2, 2', the flanks of the connecting elements 27 are each pressed onto the corresponding flanks of the recesses in the concrete slabs 2, 2', which absorb and transmit the compression and compression forces.

9e) shows a plan view of a tenth exemplary embodiment of a concrete slab construction 14 according to the invention, in which two concrete slabs 2, 2' are interlocked, the interlocking being effected by rectangular teeth instead of along a zigzag line. In this concrete slab construction 14, only the horizontally running sides of the concrete slabs 2, 2' are connected to one another by means of joining elements 1, the vertically running sides of the concrete slabs 2, 2' only abut one another and are without joining elements 1. In this concrete slab construction 14, various types of Joining elements 1 used: in the top row a variety of individual hourglass-shaped joining elements 1, which are each cemented in corresponding individual recesses 15; in the second top row there are also several individual hourglass-shaped joining elements 1, which are, however, mortared in a common recess 15; in the second row from the bottom there are several joining elements 1 with a rectangular outline, which in turn are cemented in a common recess 15 (alternatively, they could also be cemented in respective individual recesses 15); and in the bottom row it is a single long joining element 1 with a rectangular plan, which is mortared in a likewise elongated recess 15 .

Fig. 9'a) shows an alternative sixth exemplary embodiment of a concrete slab construction 14 according to the invention in a view from above. The sectional image along the line AA' in FIG. 9 ' b ) shown , i . H . the median plane in the single horizontal concrete slab 2 . The concrete slab 2 has three identical recesses 15 which have an elongated rectangular outline. In these three recesses 15 three elongate joining elements 1 are inserted for joining the concrete slab 2 with the concrete slab 2' arranged perpendicularly/vertically thereon and with a filling material 25, such as grout, which is introduced into the spaces between the recesses 15 and the joining elements 1 , tied together . The three joining elements 1 are an integral part of the concrete slab 2'. They are all at the bottom of the concrete slab 2' arranged where they are all integrally formed with the concrete slab 2'. In this example, both the recesses 15 and the joining elements 1 all have bulges or Notches, with sufficient space between the respective bulges of the recesses 15 to introduce the joining elements 1 from above into the recesses 15 without the notches of the joining elements on the concrete slab 2 ′ touching the bulges of the recesses in the concrete slab 2 . As mentioned above, the gaps are filled with filling material 25, such as grout, whereby the two concrete slabs 2, 2' are firmly connected as soon as the filling material 25 has hardened. The area between two adjacent joining elements 1 forms a web 29. It can be advantageous if the spaces 30 between the lower, horizontal concrete slab 2 and the webs 29 in the upper, vertical concrete slab 2' are open and thus the upper concrete slab 2' is not rests on the lower concrete slab 2. In this way it can be ensured, for example, that in the case of long concrete slabs 2, 2', all joining elements 1 project completely into the recesses 15, even with low manufacturing tolerances. In addition, the entire (compressive) load transfer takes place from the upper concrete slab 2' to the lower concrete slab 2 via the joining elements 1 and the recesses 15. In FIG. 9'b), the sectional view along the line BB' in FIG. 9' a) shown, ie the center plane of the upper, vertical concrete slab 2'. In addition, in FIG. 9'c) the sectional image along the line CC in FIG. 9'a) is shown, ie the Cross-sectional plane which runs transversely through the central recess 15 of the horizontal concrete slab 2 (shown hatched) and the joining element 1 on the vertical concrete slab 2'.

Fig. 10a) shows a cross section through an eleventh embodiment of a concrete slab construction 14 according to the invention, in which a joining element 1 according to Fig. 4a) with two identical joining bodies 3, 3' with notches (according to Fig. 1b)) which are connected to one another by an extension 12 are integrally connected. With this joining element 1, two upper and two lower concrete slabs 2, 2' are connected to one another and kept at a distance from one another. The vertical downward arrow indicates that the joining element 1 was introduced from above through the recess 15 between the two pairs of concrete slabs.

10b) shows a cross section through a twelfth embodiment of a concrete slab construction 14 according to the invention, in which the recesses 15 between the two pairs of concrete slabs do not run continuously through the two adjacent concrete slabs 2, 2', but rather form a blind hole. The horizontal arrows pointing to the left and right in FIG. Fig. 10 c ) shows a cross section through a thirteenth exemplary embodiment of a concrete slab construction 14 according to the invention, in which there is only one concrete slab 2 at the top and two concrete slabs 2 , 2 ′ at the bottom. The lower recess 15 between the two lower concrete slab pairs 2 , 2 ′ is continuous, as is the upper recess 15 in the individual upper concrete slab 2 . The vertical upward arrow indicates that the joining element 1 is guided from below into the recess 15 between the two lower concrete slabs 2 , 2 ′ and into the recess 15 of the individual upper concrete slab 2 . The free end of the lower joining body 3' is wider than that of the upper joining body 3 and completely closes the lower recess 15, so that when filling the filling material 25 into the intermediate space 24, no filling material 25 can escape downwards. The free end of the lower joining body 3' therefore serves as a cover for the lower recess 15. This concrete slab structure 14 can, for. B. be used in the anchoring of concrete slabs to a concrete ceiling (e.g. to form a cavity in the ceiling).

In general, the joining element can alternatively also be designed in such a way that it is wider at the bottom than at the top, so that the concrete slab(s) (e.g. after being pushed together) are flush with the joining element, so that the filling material can be filled into the intermediate space from above , without leak below. The same purpose is also achieved if the joining element has the same width at the top and bottom, but the recess in the concrete slabs is designed in such a way that it can flushly surround the joining element at the bottom, but leave a gap at the top into which the filling material can be filled.

10d) shows a cross section through a fourteenth exemplary embodiment of a concrete slab construction 14 according to the invention, in which, in contrast to the concrete slab construction 14 in FIG. 10c), the joining element 1 is arranged at the top between two concrete slabs 2, 2'. In order to facilitate assembly, the upper joining body 3 of the joining element 1 is fastened to the bulge 20' of the upper right concrete slab 2', e.g. by means of an adhesive or mortar (see hatched fastening area 28).

Fig. 11a) shows a perspective view of a fifteenth embodiment of a concrete slab construction 14 according to the invention, each with two notches 8, 8', 8'', 8''' on the left and right side 6, 7 (and an example of an extension 12' - optionally also an extension 12 shown in dashed lines at the top), which is used to connect two concrete slabs 2, 2' vertically spaced apart from one another. 11b) shows a perspective view of a sixteenth exemplary embodiment of a joining element 1 according to the invention, in which, in contrast to the joining element 1 in FIG. 12a), the length L is shorter than the width B. This too Joining element 1 has, for example, an extension 12—but here at the top (optionally also an extension 12′ shown in dashed lines at the bottom).

Fig. 11c) shows a perspective view of an alternative fifteenth embodiment of a concrete slab construction 14 according to the invention consisting of three concrete slabs 2, 2', 2'', wherein the perpendicular, vertical concrete slab 2' supports the two horizontal and parallel concrete slabs 2 & 2 '' connects. The vertical concrete slab 2' is arranged in the longitudinal direction to the other two concrete slabs 2, 2* and serves, so to speak, as a joining element between these two. For this purpose, the vertical concrete slab 2' as an integral component has (long) longitudinal notches on the lower and upper side (similar to the notches 8, 8', 8'', 8''' in FIG. 11a)). Correspondingly, the lower and upper concrete slab 2, 2* each have an incompletely continuous recess (ie a blind hole) on the upper or lower side of the upper or lower concrete slab 2, 2'' in the longitudinal direction away from the edge of the slab. The recess is filled with a filling material 25 such as grout. Fig. 11d) shows a perspective view of another alternative fifteenth embodiment of a concrete slab construction 14 according to the invention, in which, however, in comparison to the embodiment according to Fig. 11c) the upper concrete slab 2'' is missing and the vertical, vertical concrete slab 2' extends further upwards and has indentations (similar to indentations 8'', 8''' in Fig. 11a) only on the lower side, which are formed integrally with the vertical concrete slab 2'. The concrete slab 2' can basically be regarded as a joining element with an upper extension 12, which corresponds to the part of the concrete slab 2' protruding upwards from the concrete slab 2. Fig. Ile) & llf) show a perspective view of two further exemplary embodiments analogous to those of Fig. 11c) & lld), wherein the perpendicular, vertical concrete slab 2 'is arranged in the transverse direction to the lower concrete slab 2 and the upper concrete slab 2'' . Here, the vertical concrete slab 2 'as an integral part of the lower (and upper) side (short) notches between the

Front and rear of the concrete slab 2 '(analogous to the notches 8, 8', 8'', 8'' 'in Fig. 11b)). Alternatively, in the case of the exemplary embodiments illustrated in FIGS. 11c)-11f), notches could be present in the concrete slab 2' both in the longitudinal and in the transverse direction, with the result that the joint body would have notches on all four sides.

12 shows cross sections through seventeenth to twenty-second exemplary embodiments of a concrete slab construction according to the invention. In FIG. 12a), three concrete slabs 2, 2', 2*' are connected to one another by two joining elements 1 in one plane. In Fig. 12b) there are also three concrete slabs 2, 2', 2* * by two Joining elements 1 connected to one another in one plane, the joining elements 1 each having a lower extension 12', on which the concrete slab structure 14 can be supported, for example on the ground. In FIG. 12c), three concrete slabs 2, 2', 2*' are also connected to one another in one plane by two joining elements 1, the joining elements 1 each having an upper extension 12 with which the concrete slab structure 14 can be mounted, for example, on a ceiling . Fig. 12d) shows the two concrete slab structures 14 from Figs. 12b) & 12c) as they are supported on one another with the extensions 12, 12', the extensions 12, 12' also being used for the mutual anchoring of the two separate levels of concrete slabs can be used. For example, the upper concrete slabs can serve as a compression chord with the roadway and the lower concrete slabs as a tension chord of a light concrete bridge. In Fig. 12e) two spaced levels of concrete slabs 2, 2' are connected to one another with two joining elements 1, the joining elements 1 in turn each having a lower extension 12', with which the concrete slab constructions 14 can be supported, for example on the ground. The left joining element 1 is inserted in the two left concrete slabs 1 and serves as a spacer and support for the two left concrete slabs. Fig. 12f) shows, conversely, two spaced planes of concrete slabs, which are connected to one another with two joining elements 1, each of which has an upper extension 12 with which the concrete slab structure 14 can be anchored, for example, in a ceiling. As can be seen, the right lower concrete slab 2' is opposite to the left upper concrete slab 2 offset. FIG. 12g) shows, similarly to FIGS. 9'a)-9'c), a horizontal basic structure which is connected to a vertical concrete slab 2''. The basic structure consists of two horizontal concrete slabs 2, 2', which are connected to one another by the central joining element 1 on the vertical concrete slab 2''. The two horizontal concrete slabs 2, 2' are also connected to the vertical concrete slab 2'' by means of the two outer joining elements 1 on the left and right. In this way, long load-bearing structures such as bridges can be realized, whereby the basic structure, which bears the actual load, consists of several (or many) horizontal concrete slabs, which are connected by a single (or few) vertical concrete slab. The recesses in the horizontal concrete slabs can be designed either directly at the edge or slightly removed from the edge, partially or completely continuously (as shown in FIG. 12g)) in the horizontal concrete slabs.

The concrete slab constructions shown can in turn serve as building blocks for entire concrete buildings. For this purpose, the different concrete slab constructions according to the invention can be combined with one another, so that the resulting concrete structure is also a concrete slab construction according to the invention. LIST OF REFERENCE MARKS

1 joining element

2, 2', 2'' concrete slab

3 joining bodies

3' Further joining body

4 upper area / top of the joining body

5 lower area / underside of the joining body

6 one side of the joining body (e.g. left, right, front, back; lengthwise, crosswise)

7 other/opposite side of the joining body (e.g. right, left, back, front; crosswise, lengthwise)

8.8' notch of the joining body (left/right)

8' ',8' ' ' Further indentation of the joining body (left/right)

9.9' bulge of the bonded body (left/right)

9' ' ,9' ' ' Further bulge of the joining body (left/right)

10 Tip of notch/bulge of bonded body

11,11' Flank of the indentation/bulge of the joining body

(upper/lower)

12,12' extension (upper/lower) on the joining body

13 Reinforcement of the joining element

14 concrete slab construction

15 Recess in the concrete slab / between the two concrete slabs 16 Top of concrete slab

17 Underside of the concrete slab

18 Left side of the recess

19 Right side of the recess

20,20' bulge in the recess / on the concrete slab (left / right )

21,21' Notch in the recess / on the concrete slab (left / right)

22 Tip of the bulge/indentation in the

Recess / on the concrete slab

23.23' Flank of bulge/indentation in recess/concrete slab (upper/lower)

24 Space between the recess / concrete slabs and the fastener

25 filling material in the gap

26 Reinforcement of the concrete slab

27 fastener (above the fastener)

28 mounting area

29 jetty

30 free space at the bridge (-> bridge does not sit on)

B Width of the joining body

B' Width of passage in/between the

Concrete slab(s) (to insert the fastener)

D diameter of an opening of the indentation or an exit of the bulge H Height of the joining body

L length of fastener a angle between the top and the top

(shorter) flank of the notch/bulge of the joining body ß Angle between the underside and the lower

(longer) flank of the notch/bulge of the joint body cp angle between the two flanks of the

Indentation/bulge of the joining body cp 'angle between the two flanks of the

Bulge/notch in or on the concrete slab (in the recess or on the edge/outer perimeter)

Claims

- 69 - CLAIMS

1. Concrete slab construction (14) comprising at least one concrete slab (2), in particular at least one FRC or CPC slab, and at least one joining element (1) made of concrete, in particular of FRC or CPC, for connecting concrete slabs (2,2' ) and / or for attachment to a concrete slab (2), wherein the joining element (1) has a joining body

(3) having an upper area (4) and a lower area (5), and a cross section of the joining body (3) between the upper area (4) and the lower area (5) on one side (6) and on one opposite side (7) each having at least one notch (8.8 ') or bulge (9.9'), wherein the notch (8.8 ') or

Bulge (9,9 ') in particular two to a tip (10) tapering or wedge-shaped flanks (11,11'), in particular flat flanks (11,11 '), wherein the two flanks (11,11') a form an obtuse or acute angle (cp), and wherein there is at least one bulge (20) or indentation (21) along a lateral periphery of the concrete slab (2) between a top (16) and a bottom (17) of the concrete slab (2). , wherein the bulge (20) or indentation (21) has in particular two or wedge-shaped flanks (23,23') tapering to a point (22), in particular flat flanks (23,23'), and wherein the joining element (1 ) is arranged on the lateral periphery of the concrete slab (2), the notch (8, 8 ') or bulge (9,9') on one side of the joining element (1) and the

bulge (20) or notch (21) of the concrete slab (2) - 70 - facing each other, and wherein a filling material (25) is located in an intermediate space (24) between the concrete slab (2) and the joining element (1), the filling material (25) being, for example, mortar or an adhesive.

2. Concrete slab construction (14) comprising at least one concrete slab (2), in particular at least one FRC or CBC slab, and at least one joining element (1) made of concrete, in particular of FRC or CPC, for connecting concrete slabs (2,2' ) and / or for fastening in a concrete slab (2), wherein the joining element (1) has a joining body

(3) having an upper area (4) and a lower area (5), and a cross section of the joining body (3) between the upper area (4) and the lower area (5) on one side (6), and in particular also has at least one indentation (8,8') or bulge (9,9') on another, in particular opposite, side (7), the indentation (8,8') or bulge (9,9') in particular two to a point (10) tapering or wedge-shaped flanks (11,11'), in particular flat flanks (11,11'), wherein the two flanks (11,11') form an obtuse or acute angle (cp). , and wherein the concrete slab (2) has at least one recess (15), a cross section of the recess (15) between an upper side (16) and an underside (17) of the concrete slab (2) on one side (18), and in particular also has at least one bulge (20,20') or indentation (21,21') on another, in particular opposite, side (19), wherein the bulge (20,20') or indentation - 71 -

(21,21'), in particular two tapering or wedge-shaped flanks (23,23'), in particular flat flanks (23,23'), and wherein the joining element (1) in the recess (15 ) is arranged, with the respective indentation (8,8') or bulge (9,9') of the joining element (1) and the respective bulge (20,20') or indentation (21,21') of the recess (15 ) face each other, and wherein a filler or a filling material (25) is located in an intermediate space (24) between the recess (15) and the joining element (1), the filler or the filling material (25) being, for example, at least one fitting piece, like a wedge, or mortar, sand or an adhesive.

3. Concrete slab construction (14) comprising at least two concrete slabs (2,2'), in particular at least two FRC or CPC slabs, and at least one joining element (1) made of concrete, in particular of FRC or CPC, for connecting concrete slabs (2 , 2 ') and / or for attachment to a concrete slab (2), wherein the joining element (1) has a joining body

(3) with an upper area (4) and a lower area

(5), and a cross section of the joining body (3) between the upper area (4) and the lower area (5) on one side (6) and on an opposite side (7) each having at least one notch (8,8' ) or bulge (9.9 '), wherein the notch (8.8') or

Bulge (9,9'), in particular two tapering or wedge-shaped flanks (11,11'), in particular flat flanks (11,11'), with the two flanks (11,11') form an obtuse or acute angle (cp), and along a lateral circumference of the concrete slabs (2,2') between a top (16) and a bottom (17) of the concrete slabs (2,2') at least one bulge (20,20') or indentation (21,21') is present, the bulge (20,20') or indentation (21,21') in particular two tapering or wedge-shaped to a point (22). Flanks (23,23 '), in particular flat flanks (23,23'), and wherein the joining element (1) between the two concrete slabs (2,2 ') is arranged in a recess (15), with the respective Notch (8, 8') or bulge (9,9') of the joining element (1) and the respective bulge (20,20') or notch (21,21') of the concrete slabs (2,2') face each other, and wherein there is a filler or filling material (25) in a space (24) between the concrete slabs (2,2') and the joining element (1), the filler or filling material (25) for example having at least one fitting piece, such as a Wedge, or mortar, sand or an adhesive.

4. concrete slab structure (14) according to claim 2 or 3, wherein the recess (15) is at least as wide as the width (B) of the joining element (1) or joining body (3).

5. Concrete slab construction (14) according to one of claims 2 to 4, wherein the recess (15) runs continuously through the concrete slab (2,2') or the recess (15) only partially runs into the concrete slab (2,2'). . - 73 -

6. Concrete slab construction (14) according to one of claims 1 to 5, wherein the two flanks (11,11') of the notch (8,8') or bulge (9,9') of the joining element (1) and the two flanks (23,23') of the bulge (20,20') or indentation (21,21') in or on the concrete slab (2,2'), and one flank (23,23') of the bulge (20 ,20') or notch (21,21') in or on the concrete slab (2,2') from an upper side of the concrete slab (2,2') and the other flank (23', 23) from a lower side of the concrete slab (2,2'), these two flanks (21,21') of the bulge (20,20') or indentation (21,21') forming an obtuse or acute angle (c').

7. Concrete slab construction (14) according to one of claims 1 to 6, wherein the joining element (1) is an integral part of a concrete slab (2,2'), in particular on a lateral periphery of the concrete slab (2,2') in one piece with the concrete slab ( 2.2') is formed.

8. Concrete slab construction (14) according to one of claims 1 to 7, wherein the at least one notch (8,8') or bulge (9,9'), in particular the two flanks (11,11'), at least in part, in particular completely, within, in particular between the top (16) and the bottom (17), the concrete slab (s) (2.2 ') are located. - 74 -

9. Concrete slab construction (14) according to one of claims 1 to 8, wherein a cross section of the joining body (3) between an upper side (4) and a lower side (5) is hourglass-shaped, in particular the joining body (3) is hourglass-shaped, more particularly that the top (4) and the bottom (5) of the joining element (1) are round or oval.

10. Concrete slab construction (14) according to one of claims 1 to 9, wherein the notch (8) or bulge (9) of the joining element (1) on one side (6) and the notch (8 ') or bulge (9') on the opposite side (7) of the joining element (1) are uniform, the cross-section is in particular mirror-symmetrical, further in particular point-symmetrical.

11. Concrete slab construction (14) according to one of claims 1 to 10, wherein the indentation (8,8') or bulge (9,9') of the joining element (1) has an upper flank (11) and a lower flank (11') ), wherein the upper flank (11) and the lower flank (11 ') are of the same length or different lengths, in particular the length ratio of the shorter flank (11) to the longer flank (11') in a range from 1:16 to 1:1.

12. concrete slab structure (14) according to any one of claims 1 to 11, wherein a height (H) of the joint body (3) between the upper area (4) and the lower area (5) or between the top (4) and the bottom (5) in one range from 2 cm to 10 cm, and/or wherein a width (B) of the joining body (3) between one side (6 and the opposite side (7) is in a range from 2 cm to 10 cm.

13. Concrete slab structure (14) according to one of claims 1 to 12, wherein a length (L) of the joining element (1) is in a range from 5 cm to 20 m, in particular up to 1 m, more particularly up to 50 cm.

14. Concrete slab construction (14) according to one of claims 1 to 13, wherein the joining body (3) is attached to the upper area (4) or to the top (4) and/or to the lower area (5) or to the underside (5 ) has an extension (12,12'), the extension (12,12') being designed in particular as a coupling element for coupling to another component.

15. Concrete slab construction (14) according to claim 14, wherein a further joining body (3') is arranged on the extension (12, 12'), and in particular the further joining body (3') and the extension (12, 12') together in one piece are trained.

16. concrete slab structure (14) according to any one of the claims

1 to 15, wherein the joining body (3) between the upper area (4) or the top (4) and the lower area

(5) or the underside (5) on at least one side (6) has at least one further indentation (8'', 8''') or at least one further bulge (9'', 9''').

17. Concrete slab construction (14) according to one of claims 1 to 16, wherein the joining element (1) has a reinforcement (13), e.g. a reinforcement made of steel, in particular a reinforcement (13) made of fibers, such as e.g. carbon, glass , Stone, natural or plastic fibers, wherein the reinforcement (13) is aligned in particular substantially perpendicular to the top (4) and bottom (5).

18. Concrete slab construction (14) according to one of claims 2 to 17, wherein on or in the upper side (16) and/or the lower side (17) of the concrete slab(s) (2, 2'), in particular above the joining element (1) , a connecting element (27), in particular a plate, strip or hourglass-shaped connecting element (27), is arranged, which is connected to the concrete slab (2) or the two concrete slabs (2,2'), for example screwed on, is dowelled or glued, the connecting element (27) being particularly suitable for absorbing tensile forces.

19. Concrete slab construction (14) according to one of claims 2 to 18, wherein a plurality of joining elements (1) are arranged along a straight line at intervals, in particular regular intervals, in the concrete slab (2) or between the concrete slabs (2, 2'). - 77 -

20. Concrete slab construction (14) according to one of claims 2 to 18, wherein a plurality of joining elements (1) along a serpentine line or a zigzag line at intervals, in particular regular intervals, in the concrete slab (2) or between the concrete slabs (2, 2 ') are arranged, the serpentine line being composed in particular of curved sections and the zigzag line being composed in particular of straight sections.

21. Concrete slab construction (14) according to claim 19 or 20, wherein both joining bodies (3) with and without extension (12,12') are arranged in the concrete slab (2) or between the concrete slabs (2,2'), in particular in a regular pattern, in particular joining bodies (3) with and without extensions (12, 12') are arranged alternately.

22. Concrete slab construction (14) according to one of claims 2 to 21 with at least one joining element (1) according to claim 15, in particular according to claims 15 and 17, wherein the joining element (1) is located between two spaced-apart stacked concrete slabs (2,2'). , wherein the two concrete slabs (2,2') are in particular connected to one another or supported on one another by means of the joining element (1).

23. Concrete slab construction (14) according to claim 22, wherein the two spaced-apart stacked concrete slabs (2, 2') are offset from one another.

24. Concrete slab construction (14) according to claim 22 or 23, wherein some, in particular a majority, of the recesses (15) do not run completely continuously through the concrete slab (2) or through the concrete slabs (2, 2 '), and that some, in particular a minority of the cutouts (15) running completely through the concrete slab (2) or the concrete slabs (2,2'), with at least one non-continuous cutout (15) being located in particular between each two continuous cutouts (15). .

25. Concrete slab structure (14) according to one of claims 2 to 24, wherein the concrete slab structure (14) is a concrete ceiling element or a concrete ceiling comprising a plurality of concrete ceiling elements or a bridge element or a concrete bridge comprising a plurality of bridge elements.

26. Method of making a

Concrete slab structure (14) according to claim 2, comprising the steps of:

- Providing at least one joining element (1);

- Providing at least one concrete slab (2), in particular at least one FRC or CBC slab, the concrete slab (2) having at least one recess (15), a cross section of the recess (15) between an upper side (16) and an underside (17) of the concrete slab (15) on one side (18) and optionally - 79 - another, especially opposite, page

(19) each has at least one bulge (20,20') or indentation (21,21'), wherein the bulge (20,20') or indentation (21,21') has in particular two tapering or has wedge-shaped flanks (23, 23'), in particular flat flanks (23, 23'), the recess (15) running in particular continuously through the concrete slab (2) or running only partially into the concrete slab (2);

- Arranging the joining element (1) in the recess (15) so that the respective notch (8.8') or bulge (9.9') of the joining element (1) and the respective bulge (20.20') or notch (21,21') face the recess (15);

- Filling an intermediate space (24) between the recess (15) and the joining element (1) with a filler or a filling material (25), the filler or the filling material (25) for example at least one fitting piece, such as a wedge, mortar , sand or an adhesive .

27. The method according to claim 26, wherein arranging the joining element (1) in the recess (15) by inserting the joining element (1) into the recess (15) in a direction perpendicular to an upper side (16) or an underside (17) of Concrete slab (2) or by inserting the joining element (1) into the recess (15) on a lateral periphery of the concrete slab (2) in the direction parallel to - 80 -

Top (16) or bottom (17) of the concrete slab (2) takes place.

28. A method of manufacturing a concrete slab structure (14) according to claim 3, comprising the following steps:

- Providing at least one joining element (1);

- Providing at least two concrete slabs (2,2'), in particular at least two FRC or CBC slabs, along a lateral circumference of the concrete slabs (2,2') between an upper side (16) and an underside (17) of the concrete slabs (2,2' ) at least one each

Bulge (20,20') or at least one indentation (21,21') is present, the bulge (20,20') or indentation (21,21') in particular two tapering or wedge-shaped to a point (22). flanks (23,23'), in particular flat flanks;

- Arranging the joining element (1) between the two concrete slabs (2.2 ') in a recess (15), so that the respective notch (8.8') or bulge (9.9') of the joining element (1) and the respective bulges (20,20') or indentations (21,21') of the concrete slabs (2,2') face each other;

- Filling a gap (24) between the concrete slabs (2,2 ') and the joining element (1) with a filler or a filler material (25), wherein the filler or the filler material (25) for example at least one - 81 -

Fitting piece, such as a wedge, or mortar, sand or a

glue is.

29. The method according to claim 28, wherein the joining element (1) is arranged between the two concrete slabs (2, 2′) by the following steps:

- Arranging the two concrete slabs (2,2 ') on one level;

- Insertion of the joining element (1) in the recess (15) between the two concrete slabs (2,2 ');

- Merging the two concrete slabs (2,2') in the direction parallel to the plane up to a distance in a range of 1 cm to 5 cm between the respective bulge (20,20') or notch (20,20') of the concrete slabs ( 2.2') and the respective indentation (8.8') or bulge (9.9') of the joining element (1) is present, or by the following steps:

- Arranging the two concrete slabs (2.2') on a plane at a distance which is less than the widest dimension of the joint body (3) from the left to the right side (6.7);

- Pushing the joining element (1) into the recess (15) between the respective bulge (20,20') or notch (21,21') of the two concrete slabs (2,2') in a direction parallel to the upper side (16) or Underside (17) of the two concrete slabs (2,2'). 82

30. The method according to any one of claims 26 to 29, wherein when filling the gap (24) between the two concrete slabs (2,2 ') and the joining element (1) in each case a filler or a quantity of filling material (25) such in the Space (24) is introduced that inaccuracies in the shape and / or dimensions of the concrete slabs (2.2 ') and the joining element (1) are compensated.

31. The method according to any one of claims 26 to 30, with the further step:

- Fastening a connecting element (27), in particular a plate, strip or hourglass-shaped connecting element (27), on or in the top (16) and/or the bottom (17) of the concrete slab(s) (2,2' ), In particular over the joining element (1), for example by means of one or more fastening means, such as screws, or by means of an adhesive.

32. The method of any one of claims 26 to 31, further comprising the step of:

- Arranging a plurality of joining elements (1) along a straight line at intervals, in particular regular intervals, in the concrete slab (2) or between the concrete slabs (2,2').

33. The method according to any one of claims 26 to 31, with the further step: - 83 -

- arranging a plurality of joining elements (1) along a wavy line or a zigzag line at intervals, in particular regular intervals, in the concrete slab (2) or between the concrete slabs (2,2'), the wavy line consisting in particular of curved sections and the zigzag line especially composed of straight sections.

34. The method according to claim 32 or 33, with the further step:

- Arranging the joining elements (1) alternately essentially orthogonally with respect to their longest extent to one another.

35. The method of claim 32 or 33, further comprising

Step :

- arranging joining elements (1) both with and without extension (12, 12') in the concrete slab (2) or between the concrete slabs (2,2'), in particular in a regular pattern, in particular arranging joining elements (1) alternately with and without extension (12,12') .

36. The method according to any one of claims 26 to 35, with the further step:

- Arranging at least one joining element (1) according to claim 8 between two stacked spaced - 84 -

Concrete slabs (2,2') and connecting the at least one joining element (1) to at least one of the concrete slabs (2,2'), so that the concrete slabs (2,2') are connected to one another or supported on one another.

37. The method according to claim 36, wherein the two concrete slabs (2, 2′) stacked at a distance from one another are offset in relation to one another.

38. The method according to claim 36 or 37, wherein some, in particular a majority, of the recesses (15) do not run completely through the concrete slab (2) or the concrete slabs (2, 2 '), and that some, in particular a minority, of the recesses (15) run completely continuously through the concrete slab (2) or the concrete slabs (2,2'), with at least one non-continuous recess (15) being arranged in particular between each two continuous recesses (15).

39. Use of the joining element (1) from one of claims 1 to 25, in particular from claim 11, in which the upper flank (11) and the lower flank (11') are of different lengths, for absorbing forces on the joining element (1 ) and transfer of forces to the concrete slab(s) connected to the joining element (1)

(2,2'), whereby the shorter of the two flanks (11,11') is mainly used for absorbing and passing on compressive forces - 85 - and the longer of the two flanks (11,11') mainly serves to absorb and transmit tensile forces.

40. Use of the concrete slab structure (14) according to one of claims 1 to 25 as part of the following structures:

FRC or CPC supporting structures of buildings, such as wall/ceiling connections, roof structures, wall structures, (suspended) ceilings, stairs, wall/wall connections in building cores also for seismic reinforcement, basements in the ground, hollow columns, entire wall systems, self-supporting balconies, tower structures, staircases , folding works;

- Whole simple buildings, such as communal utility buildings, vehicle shelters, electrical distribution boxes, container shelters, platform/platform roofs, tram and bus shelters;

supporting structures in shipbuilding. 86

41 . Method for producing a joining element (1) from one of claims 1 to 25, comprising the following steps:

- dividing, in particular sawing, the concrete slab between notches, in particular between adjacent notches or between a plurality of adjacent notches in the direction of width extension and in the direction of length extension, in order to obtain a large number of individual joining elements (1); or alternatively comprising the following steps:

- Providing a concrete cylinder with a cylinder axis, in particular an FRC or CPC cylinder, in particular with a round, oval or polygonal cross-section;

- Milling of notches in a part of the circumference of the concrete cylinder and in an opposite part of the circumference of the concrete cylinder or in the entire circumference of the concrete cylinder, in particular perpendicular to the cylinder axis, in particular at regular intervals; 87

- Cutting, in particular sawing, the concrete cylinder between notches, in particular between adjacent notches or between a plurality of adjacent notches perpendicular to the cylinder axis in order to obtain a large number of individual joining elements (1).

42. The method of claim 41, further comprising at least one of the following steps:

- Introducing a reinforcement into the concrete slab or the concrete cylinder during the manufacture of the concrete slab or the concrete cylinder in the direction of linear expansion or the cylinder axis;

face milling of a partial circumference of the concrete cylinder, in particular before milling indentations;

- forming different notches as part of notch milling, e.g. by using differently shaped milling heads to form different parts of the fasteners, such as notches, bulges, and protrusions;

- Grinding or turning of the individual joining elements, in particular for further shaping. 88

43. A method for producing a joining element (1) from one of claims 1 to 25, with the step:

- Cutting out several joining elements (1) from a concrete slab, in particular an FRC or CPC slab, using a high-pressure water jet and/or a milling cutter and/or a jigsaw or circular saw and/or a punching tool, this being done in particular by a CNC - Machine done.

44. Method for producing a concrete slab (2, 2') for a concrete slab structure (14) according to one of claims 2 to 25, in particular according to claim 7, with at least one of the two steps:

- Cutting out a joining element (1) from the concrete slab (2,2'), in particular an FRC or CPC slab;

- Cutting out the recess (15) from the concrete slab (2,2'), in particular an FRC or CPC slab, by means of a high-pressure water jet and/or a milling cutter and/or a jigsaw or circular saw and/or a punching tool, this being done in particular by a CNC machine.