DE29711542U1 - Device for connecting reinforced concrete parts - Google Patents

Description

PFISTER & PFISTER PATENT ATTORNEYS Dipl.-lng. Helmut Pfister

European Patent Attorney

Dipl.-Phys. Stefan Pfister

D-87700 Memmingen/Bavaria

. Office1: Herrenstraße 11

21/1 Telephone 0 83 31 / 2412

Fax 0 83 31/24 07 Office 2: Buxacher Straße 9

Telephone 0 8331/65183 Fax 0 8331/65185 Postgiroamt München 1343 39-805 (bank code 70010080) Bayer. Vereinsbank Memmingen 2 303 396 (bank code 731 200 75) VAT ID No. ■ Vat Reg. No. · N° CEE DE 129 066 032

0 2 JULY 1997

Pfeifer Rope and Lifting Technology. GmbH & Co. Dr.-Karl-Lenz-Straße 66 87700 Memmingen

"Device for connecting reinforced concrete parts"

The invention relates to a device for connecting reinforced concrete parts using wire ropes, which are partially embedded in the first concrete part and whose non-embedded parts protrude into the formwork of the second concrete part to be connected.

It is known to connect concrete parts by inserting wire rope loops or the like into one concrete part at the joint, which then interact with corresponding wire rope loops of a second concrete part.

If the second concrete part is constructed from in-situ concrete, it is also possible to cast the wire rope loops into the second concrete part.

In order to facilitate the manipulation of the wire rope loops, it is known to provide box-like inserts on the formwork edge of a concrete part, which hold the wire rope loops. After the formwork has been removed, the boxes can be opened and the wire rope loops that were initially folded over are then placed in a position for connection with the adjacent second concrete part.

Wire rope loops of the type mentioned above can be used both for cast-in-place concrete parts and for precast concrete parts.

It is also known to bend reinforcements of concrete parts in the edge area so that they are located inside the formwork. For example, a box-like insert can be provided that holds the bent reinforcement bars. After the formwork has been removed and the boxes have been opened, the reinforcement bars are bent out so that a connection with neighboring concrete parts is possible.

It is often necessary to use reinforcement bars with a larger diameter in the concrete part. This increases the risk that the reinforcement bars will be torn when bent back. It also becomes difficult or impossible, as mentioned above, to bend the reinforcement bars in the edge area so that the ends are initially inside the formwork and are only bent open after the formwork has been removed. For reinforcements with a larger diameter, openings are therefore provided in the formwork, for example, through which the reinforcement bars protrude. It is also known to provide the ends of the reinforcement bars with pressed-on sleeves that have an internal thread, so that appropriately designed

Arranging rods of the adjacent concrete part can be screwed into these sleeves.

Overall, however, connecting reinforcing bars with a larger diameter that cannot be bent or are difficult to bend is very labor-intensive. This applies both when inserting the reinforcement into the formwork and when removing the formwork and when connecting adjacent concrete parts.

The invention is based on the object of proposing a device with which it is possible to connect concrete parts in particular with reinforcements of larger diameters and where the amount of work required to connect the concrete parts is significantly less than with previous methods.

To solve this problem, the invention is based on a device of the type specified at the beginning. According to the invention, it is proposed that the first concrete part has a reinforcement, the rods of which end in front of the second concrete part, that wire rope pieces are arranged parallel to the reinforcement rods in the first concrete part, for the free ends of which receiving spaces are provided in the first concrete part or openings are provided in the formwork of the first concrete part. Instead of the parallel arrangement of the wire rope pieces, it is also possible to arrange them as an extension of the reinforcement rods if a suitable force introduction into the wire rope is ensured.

The invention is based on the idea that a wire rope can withstand much greater tensile stress than a reinforcing rod of standard steel quality. The cross-section of the piece of wire rope, which takes over the tensile forces from the reinforcing rod and transfers them accordingly, is therefore much smaller than the cross-section of the reinforcing rod. This in turn means that the piece of wire rope remains sufficiently flexible so that it is not difficult to bend the free end of the piece of wire rope,

for example, in storage rooms in the formwork of the first concrete part.

The essential advantages of the device according to the invention are also obtained if no spaces are provided for the wire rope pieces in the formwork of the first concrete part, but if the formwork has openings for the free ends of the wire rope pieces. The holes in the formwork required for the wire rope pieces are much smaller than the corresponding holes for the reinforcing bars. Since the free ends remain movable, they hardly hinder work in the area of these formworks. The easy bendability is also a significant advantage when transporting prefabricated parts.

The connection of the free ends of the wire rope pieces in the second concrete part to the reinforcing bars to be arranged there can be carried out in the same way as in the formwork of the first concrete part. The wire rope pieces are then also parallel to the reinforcing bars there, for example. The force is then also transmitted in the second concrete part by the fact that the concrete is firmly connected to the wire rope pieces by the surface unevenness (composite effect), and a similar anchoring is achieved as through the rib structure on the surface of the usual reinforcing bars. It is clear that the anchoring length of the wire rope pieces must be determined accordingly in order to rule out tearing. It is possible to attach additional connections between the wire rope pieces on the one hand and the ends of the reinforcing bars on the other. However, this is not necessary.

In general, it is sufficient to arrange a single piece of wire rope parallel to the reinforcing bar. In special cases, or particularly in the case of very large

However, depending on the diameter of the reinforcement bars, it may be advisable to arrange several pieces of wire rope parallel to a single reinforcement bar. It is clear that this improves the deformability of the then thinner pieces of wire rope.

In a further embodiment of the invention, pockets are provided in the first concrete part for the free ends of the wire rope pieces. The free ends of the wire rope pieces can be inserted into these pockets, for example. After stripping the formwork, the free ends are pulled out of these pockets in order to be brought into the required position for connection to the reinforcing bars of the second concrete part.

According to a further proposal of the invention, the free ends of the wire rope pieces can be rolled up or wound up, which improves the handling of the wire rope pieces.

The receiving spaces are formed, for example, by box-like inserts in the formwork of the first concrete part. These box-like inserts are covered to prevent the liquid concrete from penetrating. When the formwork is removed, the covers are removed and the free wire rope ends are then accessible.

The receiving spaces can also be formed by easily removable coverings of the free ends of the wire rope pieces. For example, the free ends can be covered by a polystyrene covering, from which they can be easily pulled out or bent out after the concrete has hardened and the formwork has been removed. The remaining receiving openings are filled when the second concrete part is created without any special measures.

As a rule, it is sufficient for the invention, as already explained above, if the wire rope pieces are of sufficient length

laid parallel to the reinforcing bars. In special cases it may be appropriate to arrange anchoring elements at the ends of the wire rope pieces in the first concrete part. Such anchoring elements can be formed, for example, by pressed-on sleeves or loops. Such measures are appropriate if, for special reasons, the dimensions of the formwork or the concrete part do not allow the arrangement of sufficient anchoring lengths.

In another variant of the invention, the wire rope pieces used are corrugated. Such corrugation can be achieved, for example, by using a relatively easily deformable steel rod instead of one of the wire rope strands. This allows the wire rope piece to be corrugated without the wire rope strands being deformed in an unacceptable manner.

According to the invention, as stated above, the wire rope piece is arranged parallel to the reinforcing bars in the first concrete part. If the wire rope is installed long enough or if additional anchoring means are used on the wire rope, the tensile force transmitted by the reinforcing bars is passed on to the wire rope. In a variant of the invention, it is now proposed that the wire rope pieces are firmly connected at least at one end to rigid reinforcing bar sections, with the reinforcing bar sections extending parallel to the reinforcing bars of the concrete parts. The firm connection between the reinforcing bar sections and the wire rope pieces can be made, for example, by means of clamping sleeves. This embodiment of the invention has the advantage that the reinforcing bar can be connected to the wire rope piece in the workshop, while on the construction site the bar sections can be used in the same way as conventional reinforcing bars.

—7—

Some embodiments of the invention are shown schematically in the drawing.

Shown: Fig. 1

Fig.2

Fig.3

Fig. 4 a section through two concrete parts with the device according to the invention,

a section through the first concrete part before connection to the second concrete part in a modified embodiment of the invention,

a representation of a variant of the invention in different operating states,

a section through another embodiment of the invention,

Fig. 5 Fig. 6, Fig. 8, 9, 10, a view in the direction of the representation of Fig. 4,

Section through two further examples
the invention,

Representations of details of the invention.

In the illustration in Fig. 1, a reinforcing bar 3 is shown in the first concrete part 1, the end 13 of which extends approximately to the edge 14 of the concrete part 1.

A piece of wire rope 4 is laid parallel to the reinforcing bar 3, the length of which is cast in concrete and is chosen so that after the concrete has been poured into the formwork (not shown in detail), the piece of wire rope 4 is securely anchored, so that the tensile forces which the reinforcing bar 3 has to absorb are safely transferred to the piece of wire rope 4.

The concreted inner end 12 of the wire rope section 4 can carry additional anchoring means, which are not shown in detail in the drawing.

In the embodiment of Fig. 1, it is assumed that the wire rope piece extends through the formwork at the edge 14 of the concrete part 1. The free end 5 of this wire rope piece is then inserted into the formwork of the second concrete part 2 and runs parallel to the reinforcing bar 10, so that a mirror-image design is obtained.

Concrete part 1 can be cast in situ concrete. However, it is also possible to design concrete part 1 as a precast concrete part.

In the embodiment according to Fig. 2, a receiving space 9 is provided, which is formed, for example, by a suitable box made of plastic, sheet metal or the like. This box is closed by a cover 15. The box with the cover 15 receives the free ends 5 of the wire rope pieces 4. After removing the cover 15, the free ends 5 can be bent up or, due to their own elasticity, protrude essentially at a right angle from the edge 14 of the first concrete part 1. The connection to the second concrete part takes place in the manner described in connection with Fig. 1.

In the embodiment according to Fig. 3, it is provided that the wire rope pieces 4 are each bent in the receiving space 6 and

are inserted into a pocket 7. The formation of the receiving spaces 6 and 7 can be achieved, for example, by means of suitable molded bodies.

The bottom view in Fig. 3 shows the position of the wire rope section 4 that it assumes when the formwork is removed. In the middle view in Fig. 3, the wire rope section is partially pulled out of the pocket 7. In the top view in Fig. 3, the wire rope section 4 protrudes at a right angle from the edge 14.

In the embodiment according to Figures 4 and 5, the free end of the wire rope section 4 is wound up in the form of a spiral. The spiral shape can be secured, for example, by holding wires. A receiving space 8 can be formed in the concrete part 1 by means of a molded body, for example also by means of a polystyrene casing, which accommodates the winding of the free end 5. After the formwork of the concrete part 1 has been removed, the wire rope section 4 can be brought into a position with its free end that allows the connection to the second concrete part.

In the embodiment according to Fig. 6, the first concrete part 1 and the second concrete part 2 are arranged at an angle to each other. The wire rope piece 4 initially runs parallel to the reinforcing bar 3 and, during the manufacture of the concrete part 1, is housed with its free end in the box-shaped receiving space 9.

In the concrete part 2, the free end 5 is then arranged parallel to the reinforcing bar 10. The wire rope piece 4 thus transmits the tensile force between the reinforcing bars 3,10.

In the embodiment according to Fig. 7, comparatively short wire rope pieces 16 are used, which are connected by clamping sleeves 17

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and 18 are each connected by reinforcing bar sections 19, 20. The length of sections 20 and 19 is such that the forces from the reinforcing bars 3 of the concrete part 1 are transferred to sections 20, and then the tensile forces are also transferred to the reinforcement of the concrete part 2, which is not shown in detail here. During the construction of the concrete part 1, the wire rope pieces 16 with the sleeves 17 and the sections 19 are accommodated in the receiving space 9, similar to the embodiment according to Fig. 2, and can be bent open without problems after stripping the formwork by removing the cover 15, as shown in Fig. 7 in the above illustration.

Fig. 8 shows the free end 5 of a piece of wire rope, which carries a pressed-on anchoring sleeve 21. The other end of the piece of wire rope, which is cast into the concrete part 1, can also be designed in the same way.

Fig. 9 shows a variant of a wire rope piece 4 without further design.

Fig. 10 shows a piece of wire rope 16 which, similar to the embodiment of Fig. 7, is connected to a reinforcing bar section 20 using a clamping sleeve 17. The free end 5 in the embodiment of Fig. 10 can, for example, be installed in the concrete part 2 in a similar way to the embodiment of Fig. 1.

Fig. 11 shows a piece of wire rope in the form of a loop 21, whereby the loop shape provides a better anchoring.

As already stated, the main advantage of the invention is that the reinforcement parts protruding from the first concrete part remain relatively easily deformable, even if the reinforcements built into the concrete part

- 11 -

have relatively large diameters. This prevents cracks from occurring in the reinforcement when the structural steel is bent back due to the use of incorrect bending radii. It also prevents the fatigue strength from being reduced in the area of the bends back.

This also means that reinforcement bars that have been pre-bent at an angle can be replaced by flexible rope ends (Fig. 6) in accordance with the correct bending plans (in compliance with the relevant regulations). This facilitates the short-term delivery of standard products and the provision of stock instead of short-term, expensive special production.

In a further embodiment of the invention, it is advantageous if the free end of the wire rope piece has a holding device either at the end or at some distance from it, with which it is possible to connect the flexible wire rope to the reinforcement of the second concrete part. This allows the rope to be quickly hooked into the reinforcement and the disadvantages of the wire rope springing back are eliminated.

The claims filed now with the application and subsequently are attempts to formulate without prejudice to obtain more extensive protection.

The references cited in the dependent claims indicate the further development of the subject matter of the main claim through the features of the respective subclaim. However, these are not to be understood as a waiver of achieving independent, objective protection for the features of the referenced subclaims.

Features that were previously only disclosed in the description can be claimed in the course of the procedure as being of essential importance to the invention, for example to distinguish it from the prior art.

Claims (10)

PFISTER & PFISTER PATENT ATTORNEYS Dipl.-Ing. Helmut Pfister European Patent Attorney Dipl.-Phys. Stefan Pfister D-87700 Memmingen/Bavaria
Office 1: Herrenstrasse 11 Telephone 0 83 31/2412 21/9 Fax 0 83 31/24 07 Office 2: Buxacher Straße 9 Telephone 0 83 31 / 6 51 83
Fax 0 8331/65185
Postgiroamt Munich
1343 39-805 (bank code: 700100 80)
Bayer. Vereinsbank Memmingen
2 303 396 (bank code 731 20075)
VAT ID No. · Vat Reg. No. · N° CEE
DE 129 066 032 0 2.JUL11997 Protection claims ; 1. Device for connecting reinforced concrete parts using wire ropes which are partially embedded in the first concrete part and whose non-embedded parts project into the formwork of the second concrete part to be connected, characterized in that the first concrete part (1) has a reinforcement whose rods (3) end in the connection area of the second concrete part (2), that wire rope pieces (4, 16) are arranged parallel to the reinforcing rods (3) or in extension of the reinforcing rods in the first concrete part (1), for whose free ends (5) receiving spaces (6-10) are provided in the first concrete part (1) or openings are provided in the formwork of the first concrete part. 2. Device according to claim 1, characterized in that the free ends of the wire rope pieces (4) in the second concrete part (2) are also arranged parallel to the reinforcing bars (10) or in extension of the reinforcing bars of the second concrete part. 3. Device according to one or both of the preceding claims, characterized in that several Wire rope pieces are arranged parallel to the reinforcing bars (3, 10). 4. Device according to one or more of the preceding
Claims characterized by pockets
(7) in the first concrete part (1) for the free ends (5)
the wire rope pieces (4). 5. Device according to one or more of the preceding claims, characterized in that the free ends (5) of the wire rope pieces (4) are rolled up or wound up. 6. Device according to one or more of the preceding claims, characterized in that the receiving spaces (9) are formed by box-like inserts in the formwork of the first concrete part (1). 7. Device according to one or more of the preceding claims, characterized in that the receiving spaces (6-8) are formed by easily removable coverings of the free ends (5) of the wire rope pieces (4). 8. Device according to one or more of the preceding claims, characterized in that the ends (5, 12) of the wire rope pieces (4) carry anchoring elements. 9. Device according to one or more of the preceding claims, characterized in that the wire rope pieces (4) are corrugated. 10. Device according to one or more of the preceding claims, characterized in that the free Ends (5) of the wire rope pieces are formed into loops (21). Device according to one or more of the preceding claims, characterized in that the wire rope pieces (16) are firmly connected at least at one end to rigid reinforcing bar sections (19, 20) which extend parallel to the reinforcing bars of the concrete parts (1, 2). Device according to one or more of the preceding claims, characterized in that the free ends of the wire rope pieces carry holding devices for connecting these free ends to the reinforcement of the second concrete part (2). Godfather