EP0534475B1 - Cable loop insert - Google Patents

Description

The present invention relates to a cable loop insert for the connection of prefabricated concrete parts, in particular for the end face connection of concrete wall elements to one another, consisting of a closed or an open-ended, spring-elastic cable loop and an insert serving as a molded core, which closes the closed part that is elastically angled onto the formwork during the production of the precast element Encloses the head section of the rope loop.

As a generic holding device or composite reinforcement elements for the connection of cast slabs or block-shaped molded parts to one another, in particular from German Offenlegungsschrift 1 684 254, holding devices are known in which eyelet-shaped holding elements protrude from a recess determined by an insert shell part in the composite surface of the precast concrete parts or molded parts. The eyelet-shaped holding element can be an erectable steel bracket or an elastic wire loop, which is accommodated in an insert shell part in the form of an unstructured plastic housing. The holding element in the form of an erectable steel bracket or an elastic wire loop is fixed in its position by a nose-shaped attachment in the insert shell part. This insert known from the prior art essentially has two functions. On the one hand, it is intended to enclose the holding element in a sealing manner, so that the concrete mass flowing in during the production of the molded molded parts does not come into contact with the holding element. On the other hand, it should be designed in such a way that the holding element can be erected in its use position or composite position without problems and without great technical effort. So that the holding element, or the underlying holding loop the pressure of the concrete flow, which is in the manufacture of the molded parts acting on such insert shell parts, was able to withstand this molded part had to be made of high-quality plastic, in particular of fiber-reinforced plastic material.

A disadvantage of these described inserts is that the use of relatively high-quality materials makes these inserts considerably more expensive, which among other things was a reason why they were not used in practice. As practical as they were designed to make work easier, since they make it much easier to erect the holding elements in the composite layer, they were not used because they had manufacturing costs that were many times too high for their intended use. The second and probably just as important function is the fixation of the holding element within the insert shell part, because the holding element should be fixed within the sealing and protective enclosing molded part in an angled or bending shape, which is an embodiment or an order of magnitude made of the insert part necessary, which extended from the narrowest radius of curvature of the holding element in both directions of the holding element so that the element was fixed in the desired radius of curvature. In order to achieve this, the insert shell part had to be designed to be disproportionately large and stable, which, as already mentioned, appeared to be too costly for the actual intended use within molded concrete parts.

From DE-A1-33 22 646 a rope transport anchor with a non-positive connection of two adjacent rope areas to form the rope loop is also known, which has a dimensionally stable unwinding device of the rope in the form of a sleeve pressed with the rope. By bending the sleeve, the cable areas on both sides of the sleeve can be fixed in a certain angular position to be determined. This angular position once reached can only be changed again by applying a large mechanical load.

Starting from this prior art, it is the object of the present invention to make the rope loop inserts known per se with at least the same functional properties by constructive measures in their manufacture much more cost-effectively and thus to make them attractive for practical use.

This object is achieved by a cable loop insert for the connection of precast concrete parts according to the teaching of claim 1.

In other words, the invention lies in the fact that a retaining bracket is additionally arranged in the insert shell part, which deforms and pre-stresses the cable loop in a flexurally elastic manner and fixes it at least essentially at a right angle without stressing the insert shell part with these mechanical stresses. The solution according to the invention consistently separates the protective function or the enveloping function from the holding and fixing function. As a result of this separation of the two functions from one another, the actual insert shell part can sealingly enclose the head section of the rope loop both on the concrete side and on the formwork side and prevent the casting compound from penetrating into the head section of the rope loop without it having to be made of expensive high-quality and high-strength material.

The support bracket additionally arranged according to the invention in the insert shell part receives the entire rope loop in an elastically deforming manner and fixes the rope loop completely without the involvement of the insert shell part.

In addition to the problems with assembly, there are also safety-related problems, because the head sections of the rope loops that are to be erected in the bonded position must have a prescribed length for the secure bond. The right-angled fixation on the formwork side is necessary in order to anchor the entire rope loop insert firmly in the concrete during the manufacture of the precast concrete elements or wall elements by pouring. The head section of the rope loop is angled and fixed to the formwork during manufacture of the finished parts. The rope loop can be closed on the concrete side or open-ended and can even be equipped at its ends with additional angled end parts and reinforcing elements for better anchoring in the molded part.

The head section which erects itself spontaneously by elastic resetting after being released from an abutment in the holding bracket is designed as a loop.

A cross bolt between the side surfaces of the short U-profile section fixes and clamps the inserted rope loop between the abutment for the rope loop head section and the bottom surface of the U-profile. During the pre-assembly of the cable loop insert, this clamping of the cable loop into the support bracket is carried out in such a way that the entire cable loop is inserted from its flat configuration with bending into the support bracket, an angled section of the head portion of the cable loop being angled onto the abutment. If the cable loop is inserted and angled in the holding bracket in this way, the cable loop is fixed or clamped by the cross bolt, which is inserted for this purpose or shot into the U-profile.

The rope loop preassembled in this way is now fixed in a right-angled, angled shape and is then inserted into an insert shell part. The angled head section of the rope loop is covered by the insert shell part and lies against the formwork side, the longer part of the rope loop body is fixed in such a way that it protrudes into the prefabricated concrete part. The insert shell part takes up both the head section of the rope loop and the support bracket and encloses both both formwork and concrete sealing. The insert shell part is configured so that it forms a mold core on the concrete side to form a locking cavity in the precast concrete part. In a preferred embodiment, the insert shell part is configured differently in its longitudinal dimension and also in its concrete-side dimension, depending on the size and shape of the cavity to be formed, as the mold core for forming this cavity in the precast concrete part. If the insert shell part only has to fulfill an enveloping function, it is preferably designed as a cheap and easy-to-produce blister pack.

The formwork-side part of the insert shell part or the blister pack has, for example, a smooth edge and outer edge area onto which a protective plate provided with a guide can be pushed. Preferably, however, the flat formwork-side cover of the insert shell part is detachably clipped onto this shell part.

According to one embodiment, the insert shell part can be equipped with mounting brackets or mounting openings for fastening to the formwork. These mounting brackets or openings are advantageously arranged on the smooth outer edge regions or opposite one another on the smooth edge regions or on or in molded-on tabs.

The insert shell part according to the invention, which has an additional retaining bracket, has the advantage that, on the one hand, the retaining bracket, as a relatively small, compact construction, fixes the rope loop at a right angle, whereby this preassembled rope loop retaining part is received by the insert shell part and only has to be enveloped by it in a sealing manner. This has the consequence that the material used for the insert shell part can be an inexpensive blister-like profile-stiffened plastic capsule.

• Fig. 1 eine Seitenansicht der im Haltebock winklig fixierten Seilschlaufe in einem Einlegeteil;
• Fig. 2 eine schematische Darstellung des scha-lungsseitigen Widerlagers des U-Profiles mit eingelegtem Seilschlaufenkopfabschnitt und
• Fig. 3 eine schematische Darstellung des in das Betonfertigteil hineinragenden Abschnittes des Haltebockes.

The invention is explained in more detail below using an exemplary embodiment in conjunction with the drawings. Show it:

• Figure 1 is a side view of the cable loop fixed at an angle in the support bracket in an insert part.
• Fig. 2 is a schematic representation of the formwork abutment of the U-profile with inserted rope loop head section and
• Fig. 3 is a schematic representation of the protruding into the precast section of the bracket.

The cable loop insert part according to the invention essentially consists of a cable loop 2 with a head section 3, a support bracket 4 with a bolt 5 and an all-encompassing insert part 1, which in turn is formed in two parts and consists of an insert shell part 11 and a flat cover 12 on the formwork side. The insert shell part 11 and the cover 12 are additionally supported against one another by profile elements 13.

The bracket 4 is designed as a robust and compact U-profile section, a manufactured by the injection molding process Plastic molding. The support bracket 4 receives the rope loop 2 elastically deforming and at least essentially at a right angle. The two free ends of the wire rope protruding into the concrete part are positively connected to one another to form a loop.

The head section 3 of the rope loop 2 is in any case designed as a closed loop.

The support bracket 4 is a short U-section and consists of a bottom surface 7 and an abutment 8 which at least partially closes the U-section. The U-section is open on the concrete side with an abutment 8 on the formwork side for the head section 3 of the cable loop 2. Between the opposite U-profile section 10 extends a cross pin 5. This cross pin 5 clamps the inserted cable loop 2 between the formwork-side abutment 8 and the bottom surface 7 of the U-profile. The cross bolt 5 is expediently mounted after the cable loop 2 has been inserted into the holding bracket 4. The abutment 8 of the head part 3 of the rope loop is slotted in the middle or has a central through-channel or a central recess in which the head part 3 of the rope loop can be erected from the bent or angled position to its position intended for the manufacture of the precast element composite . This central recess extends essentially through the entire abutment.

The bottom surface 7 of the U-profile, which extends at least substantially at right angles to the abutment 8, has reinforcing ribs 9 which increase in the direction of the formwork side. These reinforcing ribs 9 are configured as a function of the diameter and consequently as a function of the size of the bending forces to be absorbed. The reinforcing ribs 9 are formed in an extension of the central recess in the abutment, on the outside of the bottom surface 7 of the U-profile. The inside of the bottom surface 7 of the U-profile is equipped with guide grooves 6 which receive the closed part of the rope loop which projects into the concrete. These guide grooves 6 have essentially the task of the rope loop in the predetermined angle and in the central position in the bracket fix the trestle and thus prevent the rope loop from twisting or slipping out of the specified position. They also serve to seal the interior of the insert against the penetration of casting compound when pouring the precast concrete parts.

The rope loop, which is clamped and fixed in this way, is inserted into the insert shell part to produce the precast concrete elements or concrete wall elements. The insert shell part 11 is dimensioned such that it surrounds the head section 3 of the rope loop 2 and the holding bracket 4 in a sealing manner on the concrete side.

The insert shell part has a profiled edge onto which a protective plate provided with a guide can be pushed or clipped on.

The manufacture of the precast concrete elements or wall elements is carried out in such a way that several pre-assembled cable loop insert parts are attached to the formwork at a distance from one another, if necessary even only placed on or placed on the formwork, the prepared formwork body is then poured out with concrete and thereby the rope loops are cast in and thus firmly anchored. After the concrete parts have hardened, the formwork is removed. The head sections of the rope loops, which are encased in the insert shell part or in the blister pack, remain on the composite sides. For the production of the actual composite of the concrete wall elements with each other, the cover is first removed from the insert shell part 11 and then the head section 3 of the rope loop 2 is released from the abutment 8 of the support bracket 4 by a short compression and guided into its intended functional position through the centrally open recess in the abutment 8 . Often guiding through this open recess in the abutment is not necessary at all, since the release of the locking mechanism automatically causes the spring-elastic reinforcement elements or the rope loops to jump out of the tensioned into the relaxed free position.

Claims (9)

1. A rope loop insert for connecting the reinforcement joints of prefabricated concrete parts, for the transport thereof as well, more particularly for connecting the end faces of concrete wall elements, consisting of a resilient rope loop (2) which is either closed or clamped with open ends, to form an anchoring and retaining element, and an insert (1) which serves as a hollow mould core and which receives and encloses with a matching shape the closed head portion (3) of the rope loop (2), which during production of the prefabricated concrete part is bent elastically on to the formwork, characterised in that a retaining bracket (4) is additionally disposed in the insert (1) and fixes the rope loop (2) with elastic deformation and so as to clamp it at least substantially at right angles, without any mechanical stressing of the insert.
2. A rope loop insert according to claim 1, characterised in that the retaining bracket (4) is a short U-profile portion which on the concrete side is open and which on the formwork side is provided with an abutment (8) for the head portion (3) of the rope loop (2), a transverse pin (5) clamping the inserted rope loop (2) at an angle between the abutment (8) on the formwork side and the base surface (7) of the U-profile.
3. A rope loop insert according to claim 1 or 2, characterised in that the insert (1) is a thin-walled hollow plastic member in the form of a blister which sealingly encloses the head portion (3) of the rope loop (2) and the retaining bracket (4) on the formwork side and on the concrete side, said hollow plastic member on the concrete side being configured as a mould core for forming a cavity in the prefabricated concrete part and, on the formwork side, being flat for flush abutment against the formwork.
4. A rope loop insert according to any one of claims 1 to 3, characterised in that the insert (1) is in two parts, namely a profiled insert shell part (11) and a flat cover (12) which are detachably interconnected, more particularly being separable by tearing apart.
5. A rope loop insert according to claim 4, characterised in that the insert shell part (11) and the cover (12) are interconnected by a detent snap connection.
6. A rope loop insert according to any one of claims 3 to 5, characterised by support elements (13) which act perpendicularly to the cover (12) and which are integrally formed on or from the cover (12) and/or the insert shell part (11).
7. A rope loop insert according to any one of claims 3 to 6, characterised in that tear strips and/or nail strips (14) which are situated flat in the major plane of the cover are formed on the latter (12).
8. A rope loop insert according to any one of claims 1 to 7, characterised in that guide grooves (6) to receive the rope loop (2) are formed on the inside of the base surface (7) of the U-profile.
9. A rope loop insert according to claim 8, characterised in that the guide grooves (6), at least on a partial portion, are profiled so as to be surface-flush and of matching shape to the cord profile of the rope loop (2).

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