EP0534475A1 - Cable loop insert - Google Patents

Abstract

The cable loop insert (1) for the interconnection of prefabricated concrete compound units, in particular for the end-face reinforcing interconnection of concrete wall elements, essentially comprises a flexurally elastic cable loop (2) and an insert element (11) serving as a hollow shaped core. During production of the prefabricated concrete compound units, this insert element (11) receives a continuous head portion (3), angled off in the direction of the shuttering, of the cable loop (2) and encloses the same in a sealing manner. The insert element (11) additionally encloses a retaining bracket (4) which elastically deforms the cable loop (2) and fixes it, at least essentially at right angles, in a clamping manner. This retaining bracket (4) is configured in the form of a U-profile and exhibits an abutment which clamps the inserted cable loop (2) in an angular manner and such that it can be detached. <IMAGE>

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 mold core, which elastically rests on the formwork during the manufacture of the precast concrete part encloses the angled closed head portion of the rope loop.

Holding devices are known as a generic holding device or reinforcing composite elements for the connection of cast slabs or block-shaped molded mass parts to one another, in which eyelet-shaped holding elements protrude from a recess in the composite surface of the prefabricated concrete parts or molded mass parts determined by an insert shell part. 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 should enclose the holding element in a sealing manner, so that the concrete mass flowing in during the production of the molded mass 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 position of use or composite position without any problems and without great technical effort. Around the holding element or the underlying holding loop against the pressure of the concrete flow during the manufacture of the molded parts To act on such insert shell parts, 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, they made it much easier to erect the holding elements in the composite layer, so little were they used because they had their actual intended use many times too high for the 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 shape or in a shape that has a bending moment, 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 to such an extent 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.

Based on this prior art, it is the object of the present invention to design the known rope loop inserts with at least the same functional properties by constructive measures to make the entire rope loop insert considerably less expensive to manufacture and thus to make it attractive for practical use.

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

In other words, the essential essence of 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 right angles 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 seal 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 during assembly, there are also safety-related problems, because the head sections of the rope loops to be erected in the bonded position must have a prescribed length for the secure bond, which cannot be the case if the head sections of the rope loops are fixed at right angles by the aforementioned . This right-angled fixation on the formwork side is necessary in order to anchor the entire cable loop insert firmly in the concrete by pouring in during the manufacture of the precast concrete elements or wall elements. The head section of the rope loop is angled and fixed to the formwork during the manufacture of the finished parts. The rope loop can be closed or open-ended on the concrete side and can even be equipped with additional angled end parts and reinforcing elements at its ends for better anchoring in the molded part.

The head section which straightens up 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 into the support bracket from its flat configuration while being bent, 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 sealed by it. The result of this is 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 rope loop fixed angularly in the bracket in an insert.
• 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 bracket 4 takes the rope loop 2 elastically deforming and at least substantially at right angles. The two free ends of the wire rope protruding into the concrete part are positively connected to each other 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 bolt 5. This cross bolt 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 cable loop is slotted in the middle or has a central through-channel or a central recess in which the head part 3 of the cable loop can be erected from the bent or angled position into 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 essentially have the task of the rope loop at a predetermined angle and in a central position in the bracket to fix 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 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 connection of the concrete wall elements to one another, 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)

Rope loop insert for the reinforcement connection composite of precast concrete parts, also for their transport, in particular for the end face composite of concrete wall elements, consisting of a closed or an open-ended spring-elastic cable loop as anchoring and holding element and a insert serving as a hollow mandrel, which is elastic during the manufacture of the precast concrete part receives and encloses the closed head section of the rope loop that is angled to the formwork,
characterized by
that in the insert part (1) there is additionally arranged a support bracket (4) which fixes the cable loop (2) elastically deforming and at least essentially clamping at right angles without mechanical stress on the insert part. Rope loop insert according to claim 1
characterized by
that the support bracket (4) is a short U-profile section, which is open on the concrete side and provided on the formwork side with an abutment (8) for the head section (3) of the rope loop (2), a cross bolt (5) inserting the rope loop (2) angularly clamped between the formwork-side abutment (8) and the bottom surface (7) of the U-profile. Rope loop insert according to one of claims 1 or 2,
characterized by
that the insert (1) is the head section (3) of the rope loop (2) and the support bracket (4) on the formwork side and the concrete side sealingly enclosing thin-walled blister-like hollow plastic body that is configured on the concrete side as a mold core to form a cavity in the precast concrete part and on the formwork side for flush installation the formwork is flat. Rope loop insert according to one of claims 1 to 3,
characterized by
that the insert (1) is in two parts, namely consists of a profiled insert shell part (11) and a flat cover (12) which are detachably connected to one another, particularly by tearing. Rope loop insert according to claim 4,
characterized by
that the insert shell part (11) and the lid (12) are connected to one another by a snap-fit snap connection. Rope loop insert according to one of claims 3 to 5,
characterized by
Support elements (13) which act perpendicularly to the cover (12) and are molded or molded on the cover (12) and / or on the insert shell part (11). Rope loop insert according to one of claims 3 to 6,
characterized by
that tear tabs and / or nail tabs (14) are formed on the lid (12) in the main plane of the lid. Rope loop insert according to one of claims 1 to 7,
characterized by
that that on the inside of the bottom surface (7) of the U-profile guide grooves (6) for receiving the rope loop (2) are formed. Rope loop insert according to claim 8,
characterized by
that the guide grooves (6) are profiled at least on a partial section flush with the shape to complement the cord profile of the rope loop (2).

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