ES2396476T3 - Use of connecting elements for the connection of precast concrete parts - Google Patents

Abstract

In a construction project requiring the use of steel wire-reinforced concrete, wire loops (2) are anchored at each end (3) in a closed frame (1). The loops pass through apertures (1') close to the frame end (1a, 1b).

Description

Use of connecting elements for the connection of precast concrete parts

State of the art

In order to erect the support structures of a building constructed from prefabricated concrete pieces the prefabricated concrete parts must be connected to each other with force drag. Disk-shaped wall elements connect with each other or with vertical uprights in vertical joints. Corresponding filling slots are arranged on the front sides of the elements, on the bottom of which are provided connecting elements with protective boxes, which contain reinforcing elements that can be folded out. These reinforcement elements may be constituted both of iron for reinforcement and flexible cable elements. Such connecting elements are disclosed, for example, in WO 03/008737.

By folding these reinforcing elements outwardly, loop-type elements are made available perpendicular to the front side which, when joined together, the prefabricated part elements overlap the joint. Loops that overlap the joint are most often covered over the entire height of the prefabricated part elements in the joint filled with joint mortar. After hardening, the filler joint, thanks to the overlapping connector elements, can transmit forces in different directions, that is, on the one hand tensile forces in the overlap perpendicular to the front side of the prefabricated part elements, on the other hand forces transverse perpendicular to the disk plane and, especially importantly, a transverse force parallel to the longitudinal direction of the joint. The latter represents a case of load in the construction practice that appears very frequently.

For the transmission of transverse forces parallel to the joint, different industrially manufactured connector elements are known, as schematically shown in Figure 5. There are continuous profile elements (Figure 5c)), such as the VS® Pfeifer rail, for example. the VS® Pfeifer slat, Betomax-Schlaufmax, the Philipp rail and also individual elements (figures 5a), b)) which, by repeated multiple arrangement of reinforcement loop elements in the joint of prefabricated parts, will ensure the transmission of transversal forces. The lengths of these rails and slats are found for logistical reasons at approximately 1.20 m. To reach the ceiling height, several rail elements are joined together without intermediate space. When fewer loops in a joint are required, then individual protection boxes are used with in each case only one loop with individual separation. For example, in two-story building, two individual loops may be required above.

The individual elements include, for example, the Pfeifer VS® box (figure 5a)) and the Philipp connection loop (figure 5b)). Both have in common that it is an elongated protection box, in which one end is a cable loop that can be housed inside the protection box. The total length is fundamentally adjusted to the loop and is fundamentally shorter than the rails and slats. In the final state the individual boxes are arranged at the bottom of the filling groove, and the loops opposite each other are folded out and connected with overlap by the mortar introduced and hardened.

However, in the case of the known connecting elements it has been shown that especially in the area of individual elements and / or free edges an early formation of cracks appears in the concrete or mortar of the connection, whereby the ability to damage support, rigidity and durability of the connection.

Document US 6,308,478 B1 also discloses a connector device with a plurality of for example four or more loop elements, which can be housed in a common protection box and bent therefrom from the outside. In addition, document CH 666931 discloses a connector device with a protection box and a plurality of uniformly arranged iron mounting elements, which can be housed in the protection box and bent therefrom from the outside.

Exhibition of the invention

Therefore, it is the objective of the present invention in the case of a connection with transverse force drag of prefabricated concrete pieces to enable an improved support behavior of a connection in case of transverse force solicitation.

This objective is solved according to the invention by a process for the manufacture of a precast concrete part according to claim 1, a precast concrete piece according to claim 5, a combination according to claim 8 and a use according to claim 9. Advantageous improvements of the invention are indicated in the dependent claims.

The invention is based on the knowledge that in the case of compact connecting elements with only one reinforcing loop element or at free ends of rail-like connecting elements in the case of a transverse force request, no balance of forces appears, in which the fundamental tensile forces in the connection are absorbed by reinforcing elements.

The invention therefore relates to configuring and using the connecting element, especially also in the case of compact dimensions such that the tensile forces, which are produced in the connection as a result of an oblique concrete turntable by requesting transverse force, are absorbed and continue to be transmitted through reinforcement elements. For this purpose it is provided according to the invention that in case of a generic type connecting element the penetration openings of the two reinforcement loop elements are provided close to opposite ends of the protection box. In other words, in the case of the invention the two opposite reinforcement loops are in the outward bent state (final state) close to the respective ends of the protection box.

In this way, in each case the connecting element used according to the invention is obtained, a support behavior in itself closed, in which, as a result of the transverse force request, an inclined turntable can be formed in the concrete, which at its (imaginary) ends it can rest on the reinforcement loops of the connector element to avoid the introduction of excessive tensile forces in the concrete

or mortar. In this way, harmful cracking in the connection zone can be effectively prevented, which in addition to the support capacity also clearly increases the durability and stiffness of the connection. The connecting element according to the invention has at the same time a simple construction and can be used without problems without modifying the construction development up to that time.

In this respect, a connecting element with exactly two reinforcement loop elements represents a configuration according to the invention. This can be used in a very variable manner and, in contrast to the known individual elements, has a clearly improved support behavior, which is itself closed.

According to an improvement of the present invention it is provided that the maximum separation of the penetration openings close to the ends with respect to one end in the longitudinal direction of the protection box is less than 0.5 times a loop length, with the that the reinforcing loop elements protrude from the protection box in the folded out state. This provides a particularly compact connector element. In addition, a concrete turntable that is formed as a result of the transverse force request in case of an arrangement close to the edge of the penetration openings and therefore of the built-in reinforcement loop elements can be effectively supported at the located ends of next way of the protection box, so that the support behavior of the connector element is further improved. In this regard it is preferred that the maximum separation of the penetration openings near the ends with respect to one end in the longitudinal direction of the protection box is less than 0.25 times, particularly preferably 0.1 times the length loop

With respect to the compact incorporation and delivery dimensions of the connector element according to the invention, it is provided according to an improvement that the length of the protection box is less than 2.5 times a loop length, with which the reinforcing loop elements protrude from the protection box in the folded out state. However, at the same time, this configuration also ensures that the reinforcement loop elements in the built-in state are sufficiently close together, so that the inclination of a turntable that is placed between the reinforcement loop elements does not become too small and therefore the pressure forces that occur do not become excessively large. An even more compact connecting element is obtained according to the invention when the length of the protection box is less than 1.5 times the loop length.

According to an improvement of the invention, it is further provided that at least two reinforcement loop elements, in the state housed in the protection box, are directed towards each other and preferably overlap at least partially, so that the connecting element according to the invention, it has practically no dimensions greater than a known individual loop element, although it has a drastically improved support behavior.

In order to guarantee an effective additional absorption and transmission of the forces that appear as a result of a transverse force request in the concrete, it is provided according to an improvement of the present invention that the base of the protection box is profiled at least by sections by means of elevations and / or depressions. This ensures that the reinforcement loop elements of the connector element are also activated in the event of a transverse force request, before excessive cracking and deformation occurs in the area of the connection. In this regard it is especially preferred that the elevations and / or depressions are provided adjacent to the penetration openings, so that the desired closed support system is produced including the reinforcing loop elements.

The connecting element according to the invention can be used individually or in combination with connecting elements of the same or other type. In this way, with a locally limited measure, the support behavior of the entire connection is advantageously influenced.

Brief description of the drawings

Figure 1a schematically shows a perspective view of a first embodiment of the connecting element according to the invention;

Figure 1b schematically shows a perspective view of a second embodiment of the connecting element according to the invention;

Figure 2 schematically shows a perspective view of a third embodiment of the connecting element according to the invention;

Figure 3 schematically shows the presentation of a model of the support behavior of two prefabricated concrete pieces connected to each other by connecting elements;

Figure 4 schematically shows a connection with transverse force drag of precast concrete parts using the connecting element according to the invention;

Figure 5 schematically shows connecting elements according to the state of the art.

Detailed description of preferred embodiments

Preferred embodiments of the invention will now be described in detail with reference to the accompanying drawings.

Figure 1a schematically shows a connecting element 20 according to a first embodiment of the present invention. The connecting element 20 serves for the connection with drag of transverse force of prefabricated concrete pieces to a joint with transverse forces parallel to the longitudinal direction of the joint and comprises a protection box 1 as well as two reinforcement loop elements 3 which can bend out. The protection box 1 has an elongated shape, as a hollow box with a length L and two ends 1a, 1b on the longitudinal front side. Two openings 1 ’, 1’ are provided in a base of the protection box 1c, in which the reinforcement loop elements 3 penetrate the protection box 1.

In the case of the reinforcement loop elements 3 it can be for example a steel bar for concrete or flexible cable elements, which at their free ends are connected through a clamping element 2, sleeve or the like.

The penetration openings 1 ', 1' are provided according to the invention close to the opposite ends 1a, 1b of the protection box 1, as shown in Figure 1a. In this regard, it is preferred that the maximum separation shown in Figure 1a of the penetration openings 1 ', 1' 'with respect to the ends 1a, 1b of the protection box 1 be less than 0.5 times the length of Loop 1 defined in more detail below. Furthermore, the maximum separation a of the penetration openings 1 ', 1' 'with respect to the ends 1a, 1b of the protection box 1 is at least in the case of compact connecting elements preferably less than 0.1 times the length L of the protection box.

In addition, the length L of the protection box is designed such that the reinforcement loops 3 can be accommodated without problems inside the protection box 1, as shown in Figure 1a. In this regard, the loops 3 are directed towards each other unlike the prior art. Starting from this state, the loops 3 can be folded from the protection box 1 outwards, to reach the final state shown in figure 2, in which the loops 3 protrude with a loop length 1 of the protection box 1. In The embodiment shown in Figure 1a the length L of the protection box 1 is somewhat less than 2.5 times the length of loop 1.

Figure 1b shows a connecting element 20 according to a second preferred embodiment of the invention. The connector element 20 shown in Figure 1b differs from the connector element according to the first embodiment, shown in Figure 1a, in the length L of the protection box 1. This is, in the second embodiment shown in Figure 1b considerably shorter and amounts to slightly less than 1.5 times the loop length 1. In this way an even more compact connecting element is obtained in which the loops 3 in the inward folded state are arranged with overlap. Simultaneously the maximum separation a of the penetration openings 1 ', 1' 'in the second embodiment seen in an absolute manner is approximately as large as in the first embodiment, whereby however a somewhat greater ratio is obtained between the maximum separation a and the length L of the protection box.

A third preferred embodiment of the connecting element 20 according to the invention is schematically shown in Figure 2 in a perspective view. This is distinguished from the first embodiment shown in Figure 1a by means of profiles that are provided in the form of depressions 12 at the base of the protection box 1c. In this regard, the depressions 12 are provided in the present embodiment adjacent to the penetration openings 1 ’, 1’.

Figure 2 also shows the connecting element 20 with reinforcing loop elements 3 bent outwardly a length l, that is, in the final state, which adopts the connecting element in a connection of precast concrete parts. As reference point for the loop length l, in this respect, as shown in Figure 2, the base of the protection box 1c.

A connection of precast concrete parts using the connecting element 20 according to the invention is schematically shown in Figure 4 showing both a vertical and horizontal sectional view. As can be seen especially in the horizontal sectional view, shown below, the connecting elements 20 according to the invention are provided in filling grooves 11 on the front side of prefabricated concrete parts 5 which are to be connected to each other. The prefabricated concrete pieces 5 are placed side by side with their front sides such that in the area of the filling slots 11 a joint 10 is formed, which is then filled with filling mortar. After placing one of the prefabricated concrete pieces 5 next to each other, the reinforcement loop elements 3 are folded from the protective boxes 1 outward, so that the reinforcement loop elements 3 of opposite connector elements 20 overlap each. Next, an iron mounting rod 8 for guiding through the overlaps is guided. Finally the filling of the joint is carried out, to connect the prefabricated parts 5 to each other with force drag. In this regard, the connecting elements 20, as can be seen in the upper part of Figure 4 in the vertical section, are preferably arranged uniformly by the prefabricated concrete pieces 5.

A model for the support behavior that occurs in the area of two precast concrete pieces 5 connected to each other by means of connecting elements is schematically shown in Figure 3

20. If there is a request for transverse force Q, whose direction of action is indicated schematically with arrows 6 in Figure 3, a pressure field is formed between the precast concrete parts 5 in the filling or concrete mortar. be modeled using an inclined concrete turntable 7. The concrete slat 7 inclined as a model rests at its ends on the protective boxes 1 of the connecting elements 20, contributing both the ends of the protective box 1a, 1b and the depressions 12 of the base of the box protection 1c to an improved load transfer and support of the tornapunta 7. To achieve a balance of forces, the forces 5 created by the tornapunta 7 must be absorbed from above and below. This occurs in the model by means of the reinforcement loop elements 3 arranged at the ends of the protection box, in which horizontal braces 4 are formed. An equilibrium of this type without a considerable tensile stress of the concrete can be produced by using the connecting element 20 according to the invention by the advantageous arrangement of the reinforcement loop elements 3, which has not been possible until now in the case of the elements of known individual loops. Therefore, by using the connecting element 20 according to the invention, the generation of damage and cracks in the mortar or concrete is avoided and thus the support capacity, stiffness and durability of the connection is considerably increased.

The preferred embodiments, described above in each case have exactly two reinforcement loop elements, since in this way, especially compact and versatile connecting elements are obtained with a support behavior in itself closed.

List of reference numbers

one

protection box for reinforcement loops

1a, b

protection box ends

1 C

protection box base

eleven''

penetration openings

2

end anchor loop reinforcement

3

reinforcement loop of metal or iron cable for reinforcement

4

horizontal tensile force

5

precast concrete part as a wall or upright

6

transversal force parallel to the wall joint

7

oblique tornapunta in the filling area

8

iron mounting rod for assembly

9

area with filling mortar

10

joint between two precast concrete pieces

eleven

filling slot

12

depressions or elevations to improve the action of the tornapunta

twenty

connector element

L

protection box length

5

l loop length

Claims (12)

1. Procedure for the manufacture of a prefabricated concrete part (5), in which at least one front side of the prefabricated concrete part (5) several connecting elements (20) are arranged, which are used for drag connection of transverse force of precast concrete parts (5) to a joint (10) with transverse forces parallel to the longitudinal direction of the joint and have a preferably elongated protection box (1) and exactly two reinforcement loop elements, which can be housed in the protection box (1) and bent from it outwardly, the reinforcement loop elements (3) penetrating the protection box (1) in the area of a penetration opening (1 ', 1' ') of the protection box (1) in each case, characterized in that the penetration openings (1 ', 1' ') of the two reinforcement loop elements (3) are provided close to opposite ends (1a, 1b) of the protection box (1).

2.

 Method according to claim 1, characterized in that the connecting elements (20) are arranged uniformly on the prefabricated concrete part (5).

3.

 Method according to claim 1 or 2, characterized in that the connecting elements (20) are arranged contiguously with each other.

Four.

 Method according to one of the preceding claims, characterized in that the connecting elements

(20) are arranged on the bottom of a filling groove (11) on the front side of the precast concrete part (5).

5.

Precast concrete part, in which at least one front side are arranged several connecting elements (20), which are used for the connection with drag of transverse force of prefabricated concrete parts (5) to a joint (10) with transverse forces parallel to the longitudinal direction of the joint and have a preferably elongated protection box (1) and exactly two reinforcement loop elements, which can be housed in the protection box (1) and bent therefrom, penetrating the elements of reinforcement loop (3) the protection box (1) in the area of a penetration opening (1 ', 1' ') of the protection box (1) in each case, characterized in that the penetration openings (1 ', 1' ') of the two reinforcement loop elements (3) are provided near opposite ends (1a, 1b) of the protection box (1) and because the connecting elements (20) are arranged in filling slots (11) on the side front of the precast concrete part (5).

6.

Precast concrete part according to claim 5, characterized in that the connecting elements

(20) are uniformly arranged on the precast concrete part (5).

7.

Precast concrete part according to claim 5 or 6, characterized in that the connecting elements (20) are arranged on the bottom of a filling groove (11) on the front side of the prefabricated concrete part (5).

8.

Combination of several connecting elements (20), which can be arranged on at least one front side of a prefabricated concrete part (5), are used for the connection with drag of transverse force of prefabricated concrete parts (5) to a joint (10 ) with transverse forces parallel to the longitudinal direction of the joint and have a preferably elongated protection box (1) and exactly two reinforcement loop elements, which can be housed in the protection box (1) and bent from the same outward , the reinforcement loop elements (3) penetrating the protection box (1) in the area of a penetration opening (1 ', 1' ') of the protection box (1) in each case, characterized in that the openings The penetration (1 ', 1' ') of the two reinforcement loop elements (3) are provided close to opposite ends (1a, 1b) of the protective box (1).

9.

Use of several connecting elements (20), which are used for the connection with drag of transverse force of prefabricated concrete pieces (5) to a joint (10) with transverse forces parallel to the longitudinal direction of the joint and have a protective box (1) preferably elongated and exactly two reinforcement loop elements, which can be housed in the protection box (1) and folded therefrom, the reinforcement loop elements (3) penetrating the protection box (1) in the area of a penetration opening (1 ', 1' ') of the protection box (1) in each case, characterized in that the penetration openings (1', 1 '') of the two reinforcement loop elements (3) are provided near opposite ends (1a, 1b) of the protection box (1), for the arrangement on at least one front side of a prefabricated concrete piece (5).

10.

Method, prefabricated piece of concrete, combination or use according to one of the preceding claims, characterized in that the maximum separation of the penetration openings (1 ', 1' ') close to the ends with respect to one end (1a, 1b) in the longitudinal direction of the protection box (1) is less than 0.5 times, preferably 0.25 times, particularly preferably 0.1 times a loop length (1), with which the reinforcing loop elements (3) protrude from the protection box (1) in the folded out state.

eleven.

Method, precast concrete part, combination or use according to one of the preceding claims, characterized in that the length (L) of the protection box (1) is less than 2.5 times, preferably 1.5 times, a loop length (1), with which the reinforcement loop elements (3)

5 protrude from the protection box (1) in the folded out state. Method, prefabricated piece of concrete, combination or use according to one of the preceding claims, characterized in that the at least two reinforcement loop elements (3), in the state housed in the protection box (1), are directed one towards another and preferably overlap each other at least partially. Method, prefabricated piece of concrete, combination or use according to one of the preceding claims, characterized in that the base of the protection box (1c) is profiled at least by sections by means of elevations and / or depressions (12), being provided the elevations and / or depressions (12) preferably adjacent to the penetration openings (1 ', 1' ').