EP0119652B1 - Connection and stress repartition element for concrete parts - Google Patents

Abstract

The element comprises a socket and a bar slidingly insertable into the opening of the socket. Disposed around and spaced from both the socket and the bar are at least two closed loops each, of generally rectangular shape and made from reinforcing rods. The loops are secured to the socket and the bar, respectively, in one case by welding, in another case by means of a holder. Because they are symmetrically spaced from the socket and the bar, they ensure good distribution of pressure within the concrete.

Description

The invention is based on a connecting and pressure distribution element for two components to be concreted in succession in the same plane, which are to be separated from one another by a joint, with a sleeve and a mandrel that can be slid into the opening of the sleeve, the sleeve for fastening an end formwork and for insertion into the component to be concreted first and the mandrel inserted into the sleeve hole for insertion into the component to be concreted later.

Such connection and pressure distribution elements are used to connect building or civil engineering components, such as roof panels, floor panels, ceilings, walls, supports, retaining walls, highways, which components are to be fixed in exactly the same plane. The components connected by such an element are exposed to the influence of different temperatures, so that they expand and contract in the direction of the joint.

An element of this type consisting of a mandrel and a sleeve is described in European patent application 00 32 105. The sleeve is provided with a reinforcement and a mounting plate. The mandrel that fits into the sleeve is also reinforced. The reinforcements, which are frustoconical or cylindrical on the outside, consist of an epoxy resin. The fastening plate has four holes through which the fastening plate is fastened during installation to an end formwork of the component to be concreted first. The mandrel is slidably inserted in the opening of the sleeve. The center of gravity of the gravitational forces between the mandrel and the sleeve is precisely placed on the joint between the component to be concreted first and the component to be subsequently concreted.

The reinforcements achieve a larger surface area than that of the sections of the mandrel or sleeve covered by the reinforcements. Thanks to their larger surfaces, the reinforcements distribute the forces across a larger area in the concrete. However, the larger area created in this way is still unable to fully absorb the considerable gravitational forces, so that in particular the mandrels which transmit the forces have to be made of stainless steel. The number of elements cannot be reduced to a level that would be desirable for economic reasons.

US Pat. No. 2,194,718 describes a connection and load transmission element for concrete sections of a web separated by a joint. The connection and load transmission element consists of two DÜbeJstücke, each of which is embedded in one of the construction side. An axially extending rod is inserted into the two dowel pieces. Instead of two identical dowel pieces and an axially installed rod, the rod can be integral with one of the dowel pieces. The two dowel pieces are provided on the side facing the joint with an end flange and a support flange which is integral with it and runs at right angles to it.

In this solution, it is disadvantageous that only one end flange with the supporting flange running at right angles to it is provided on the dowel piece. The axially extending rod then has no reinforcement. As a result, the surface of the element is only increased to a limited extent.

The object of the invention specified in claim 1 is to provide a connection and pressure distribution element which is equipped in such a way that it has a much larger surface area than the known elements. The better distribution of the forces should also reduce the number of such elements compared to the prior art. The production costs of such an element should also be significantly lower than those of the known elements.

This object is achieved in the connection and pressure distribution element according to the preamble of claim 1 by the features of the characterizing part of claim 1.

Each bracket is advantageously designed in a spiral shape, the outer end part of the spiral forming a rectangle and the inner end part of the spiral being welded onto the sleeve or the mandrel.

A further embodiment can consist in that each bracket in the form of a rectangle is inserted in the arms of an end-like holding device with a hub, which holding device is firmly pressed onto the sleeve or the mandrel.

The subject matter of the invention is explained in more detail below with reference to the drawing, for example.

• Fig. 1 eine perspektivische Ansicht des erfindungsgemässen Verbindungs- und Druckverteilungselementes mit einer Hülse und einem Dorn, welche beide mit jeweils zwei spiralförmig ausgebildeten Bügeln versehen sind,
• Fig. 2 eine Ansicht teilweise im Schnitt der an einer Stirnschalung befestigten und im zuerst betonierten Bauteil eingelassenen Hülse,
• Fig. 3 eine Ansicht der im zuerst betonierten Bauteil eingelassenen Hülse,vonwelchem Bauteil die Stirnschalung abgerissen wurde, und des in die Hülse eingeführten und im nachträglich betonierten Bauteil eingelassenen Dornes,
• Fig. 4 eine Ansicht einer Ausführungsform des Elementes mit einer stirnartigen Haltevorrichtung,
• Fig. 5 einen Schnitt entlang der Linie V-V der Fig. 4,
• Fig. 6 einen Querschnitt des Dornes nach der Fig. 1,
• Fig. 7 eine schematische Darstellung im Schnitt eines Kurvenabschnittes einer Autobahn mit den eingelassenen Elementen, und
• Fig. 8 eine schematische Ansicht im Schnitt eines geradlinig verlaufenden Autobahnabschnittes und einer Stützmauer mit den eingelassenen Elementen.

Show it

• 1 is a perspective view of the connection and pressure distribution element according to the invention with a sleeve and a mandrel, both of which are each provided with two spirally formed brackets,
• 2 is a view, partly in section, of the sleeve fastened to an end formwork and embedded in the first concreted component,
• 3 is a view of the sleeve embedded in the first concreted component, from which component the face formwork was torn off, and the mandrel inserted into the sleeve and embedded in the subsequently concreted component,
• 4 is a view of an embodiment of the element with an end-like holding device,
• 5 shows a section along the line VV of FIG. 4,
• 6 shows a cross section of the mandrel according to FIG. 1,
• Fig. 7 is a schematic representation in section of a curve section of a highway with the embedded elements, and
• Fig. 8 is a schematic view in section of a straight line section of the motorway and a retaining wall with the embedded elements.

The element shown in the figures serves to connect two components 10, 11 to be concreted one after the other in the same plane, which are to be separated from one another by a joint 19, as is the case in particular in the case of motorways or airfield railways. The elements embedded in the components enable the components that are exposed to different temperatures to be expanded and contracted freely. Furthermore, the element serves to distribute the forces occurring over a larger area in the concrete.

The connecting and pressure distribution element consists of a sleeve 1 and a mandrel 2 which can be slid into the opening 9 of the sleeve 1. The sleeve 1 is for fastening to an end formwork 18 for the component 10 to be concreted first and for admission into this component to be concreted first 10 determined. The mandrel 2 inserted into the sleeve hole 9 is intended for insertion into the component 11 to be concreted later. Due to the unobstructed sliding movement of the mandrel 2 in the sleeve opening 9, the two concrete components 10, 11 can expand and contract easily after concreting.

Both around the sleeve 1 and around the mandrel 2 and at a distance therefrom are at least two self-contained brackets 3, 3 'made of reinforcing bars. In the embodiment according to FIGS. 1 to 3, each bracket 3 is spiral-shaped. The outer end part 3b of the spiral forms a rectangle and the inner end part 3a of the spiral is welded onto the sleeve 1 or the mandrel 2. The spiral bracket 3 is e.g. made of reinforcing steel with a diameter of 6 to 12 mm and can be quickly wound in an automatic machine in a spiral according to FIG. 1. The outer end part 3b of the spiral is welded onto the overlapping middle part of the spiral. This creates a self-contained bracket of a rectangular structure, which is arranged at a distance from the sleeve 1 or the mandrel 2 stationary. The bracket can be quickly and precisely manufactured to the desired dimensions on the machine. About 500 pieces of such spiral stirrups can be produced per hour.

The rectangular shape of the bracket 3 is used so that the bracket 3 can be placed on the floor (e.g. lean concrete layer 20) on one of its long sides or on one of its shorter sides. As a result, the distance between the sleeve 1 and the mandrel 2 from the ground is changed as desired. In order to achieve an even more precise adjustment of the height of the sleeve 1 from the ground, at least two circular spacers 15 made of plastic are placed on the outer end part 3b of the spiral of the bracket 3 of the sleeve 1. The spacers are available in different diameters on the market.

In another embodiment according to FIGS. 4 and 5, each bracket 3 ', which has the shape of a rectangle, is inserted into arms 4a of a star-like holding device 4 with a hub 4b made of plastic. The reinforcement bracket 3 'according to this embodiment differs from the reinforcement bracket 3 according to the embodiment according to FIGS. 1 to 3 in that it is not of a spiral configuration. It has the shape of a rectangle with its end parts partially overlapping. The end parts are welded to one another in this overlap region. The arms 4a and the hub 4b of the holding device 4 are perforated in order to allow the penetration of the concrete mass through the holes 6 and thus to achieve a better adhesive connection.

The bracket 3 'in the form of a rectangle is inserted into recesses 14 in the arms 4a. The holding device 4 is firmly placed on the sleeve 1 or the mandrel 2. The arms 4a of the holding device 4 are each provided with a nail hole 8 in their end parts in order to enable the holding device 4 placed on the sleeve 1 to be nailed onto the front formwork 18. This embodiment is used for smaller dimensions of the element.

Here, too, spacers 15 can be placed on the bracket 3 'of the sleeve 1 in order to be able to determine the height of the sleeve 1 from the floor or the formwork as desired.

The sleeve is slit on its end to be laid forehead formwork 18, whereby several tabs 5 are created. The tabs 5 are provided with nail holes 8 in order to enable the tabs 5 to be nailed onto the end formwork 18 for the component 10 to be concreted first. The mandrel 2, which is most heavily loaded by the forces occurring, is made of stainless steel in the known elements; This is also the reason to avoid corrosion. It is now proposed to produce the mandrel 2 from a core 12 made of structural steel, onto which a stainless steel jacket tube 13 is pressed. This measure results in considerable cost savings. The diameter of the mandrel can vary from 16 to 40 mm. The diameter of the mandrel 2 must correspond to the diameter of the opening 9 of the sleeve 1.

In order to prevent the concrete slurry from penetrating into the sleeve 1 during the concreting of the first component 10, the sleeve is provided with a plastic cover 16 at the end adjacent the end formwork 18. A plastic cap 17 is placed on the other end of the sleeve 1.

After the first concrete component 10 has hardened, the end formwork is torn off and the plastic cover 16 is removed from the sleeve 1. Then the mandrel 2 is inserted into the opening 9 of the sleeve 1, the distance of the bracket 3, 3 'from the bracket of the sleeve 1 being at the desired distance and the joint 19 being filled with insulation material. After the second concrete component 11 has hardened, the connection is established.

The connection and pressure distribution element described above is completely in one Factory made. At the construction site, it will only be adjusted in height and folded. The assembly is very simple. The brackets of the element lie like mandrels in their specified positions without any movement and the sleeve maintains its horizontal position at the desired height. The sleeve can no longer fall down during assembly of the heavy reinforcement. A better distribution of the pressure is achieved by the stirrup symmetrically arranged at a distance from the sleeve or the mandrel.

Claims (6)

1. Connecting and pressure-distributing element for two structural components (10,11) to be concreted in succession in the same plane and to be separated from one another by a joint (19), having a socket (1) and a gudgeon (2) slidingly insertable into the opening (9) of the socket (1), the socket (1) being intended for fastening to a frontal shuttering (18) and for embedding in the structural component (10) to be concreted first, and the gudgeon (2) inserted in the socket hole (9) being intended for embedding in the structural component (11) to be concreted later, characterized in that round about the socket (1 ) as well as about the gudgeon (2) and spaced from these, at least two closed loops (3,3') respectively, made of reinforcing rods, are disposed, which loops are directly or indirectly fixed to the socket (1 ) and to the gudgeon (2), respectively.

2. Element according to patent claim 1, characterized in that each loop (3) is formed spirally, the outer end portion (3b) of the spiral forming a rectangle and the inner end portion (3a) of the spiral being welded on the socket (1) and on the gudgeon (2), respectively.

3. Element according to patent claim 1, characterized in that each loop (3') in the shape of a rectangle is inserted in arms (4a) of a star-like holding device (4) with hub (4b), which holding device is tightly pressed on the socket (1) and on the gudgeon (2), respectively.

4. Element according to patent claim 1, characterized in that there are provided at one end of the socket (1) tongues (5) which run perpendicular to the longitudinal axis (X) of the socket (1) and are intended for nailing onto the frontal shuttering (18) for the structural component (10) to be concreted first.

5. Element according to patent claim 3, characterized in that the arms (4a) and the hub (4b) of the holding device (4) are perforated, and the arms (4a) each have a nail hole (8) in their end portions.

6. Element according to patent claim 1, characterized in that the gudgeon (2) is made of a core (12) of structural steel and a jacket tube (13) of high-grade steel which is tightly pressed onto the core (12).

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