DE9001016U1 - Connecting element for a concrete cantilever slab - Google Patents

Description

Connecting element iü- &Lgr;&idiagr;&eegr;&bgr; B«t -akragplatte

The invention relates to a connecting element with a steel support for a concrete cantilever slab, according to the preamble of claim 1.

In order to prevent undesirable thermal bridges from occurring in buildings between an internal load-bearing structure and the concrete cantilever slab connected to it, various proposals have already been made.

From EP-Bl-O 119 165 a cantilever plate connection element is known with a cuboid-shaped insulation body, which is interspersed with reinforcing rods. To improve handling, the reinforcing rods are designed in the form of closed loops, which are connected to one another by cross rods running lengthways to the insulation body.

P/Z9

Telephone: 0 89-53 96 53 Telex: 5-'M 845 tipat Fax: 0 89-53 73 77

Bank (Miineton) KIo .1939 M Λ (BL; 700 BOO 00) OeuiKhe Bunk (Munich) KIo 70« 1060 (BLZ 700 700 10) Po»Hiro!KT!l (MGnch«n> Kto 670 ■ ■ ' 804 (BLZ 700 100 Λ0) THE DAMCMI KANOYO BANK. LIMITED (Monr.h«n| KIo SI042 3:1 007 (BLZ 700 ?07 00)

This design can simplify the handling and manufacture of the cantilever slab connection elements penetrated by the reinforcement elements. Nevertheless

It turns out that the assembly of such components is very 5

must be carried out carefully in order to to ensure the exact alignment of the insulation and to avoid damage to the insulation body during transport and assembly. This may extend the assembly time considerably, for example if a damaged insulation body and associated reinforcement bars have to be replaced.

On the other hand, it is already known to connect cantilevered concrete slabs via connecting elements mi;, parallel to each other &ogr;

connected upper and lower chords, between which a correspondingly undercut or broken insulation is fixed. For easier installation, these constructions are also made with relatively short, i.e. little

protruding compression rods. However, 20

the pressure force absorption capacity of these short pressure rods has proven to be relatively low, so that the invention is based on the task of creating a connection element according to the preamble of claim 1, which

a handling that is better adapted to the materials of the components used 25 / before and during assembly opens up

and a safe absorption of the compressive forces is ensured.

This object is achieved by a connecting element with a steel support with the features of claim 1.

The design of the lower chord, which is upright at the ends, ensures a particularly favourable flow of forces from the cantilever plate to the lower chord and from there to the supporting structure, and for a given steel beam height

a larger load across the range is possible in the front and rear axles, which improves the force absorption.

Advantageous further developments of the invention are the subject of the dependent claims.

The further development according to claim Z results in a simplified handling of the steel beam. Due to the measures according to the invention, the steel beam can be handled separately from the insulating body before final assembly. The handling of these more stable beams, / which is naturally relatively rough, cannot therefore have a detrimental effect on the insulating body. The

Cuff lays by the interaction with the compartment" ^r erk-15

The position of the insulating bodies between the steel beams is clearly defined. It can also be used advantageously to give the steel beam a stable base when it is placed on a house wall. In addition, the position

Fixing the sleeve over the truss web simultaneously defines the position of the beam itself, i.e. the cantilever dimension, which means that alignment work can be eliminated.

The further development according to claim 4 results in / 25
V a particularly stable construction of the steel girder, since the bending moments acting on the lower chord due to its curved end sections are thus absorbed by the truss web. This results in the same

Lower flange thickness provides increased load-bearing capacity or, in the case of pre-30

given load capacity, a weaker, more cost-effective design of the lower chord, which also enables a reduction in heat transfer.

A further advantage of the subject matter of the invention is that the cross-sectional design of the upper and lower chords can be freely selected according to the respective requirements. For cost reasons, however, it is advantageous to work with circular cross-sectional profiles and to bend the lower chord at the ends, although a welded construction of the lower chord is also possible.

Preferably, the sleeve is placed around the steel beam at the point where a web section runs at an angle to the upper and lower chords. Since the web section in the area of the sleeve is not encased in concrete, curvatures in this area must be avoided. It has been shown that if this web section is inclined at 45° to the two webs and the vertical distance between the lower and upper chords is given, a sufficiently wide sleeve can be placed around the steel beam in order to reliably fix the adjacent insulating bodies with sufficient width to fulfil the thermal insulation function.

In order to make the sleeve as strong as possible with a given distance between the upper and lower chords and with an inclination angle between the infill and the beam axis of at least 45°, it is advantageous to cut the bar forming the infill or the truss web according to the protection requirements:
welding.

(Protection claim 5 to be fixed laterally to the upper and lower chord

The manufacture of the steel beam can be further simplified if the sleeve according to claim 7

Furthermore, there is the additional advantage that the components of the steel beam made of different materials can be easily handled separately until the final assembly on site.

is possible.
3b

M ₇ -'

Below, several embodiments of the invention are explained in more detail using schematic drawings.

show:
5

Figure 1 is a perspective view of a first embodiment of a steel support for the connecting element ;

Figure 2 is a view of the steel beam according to Figure i looking in the direction II in Figure 1.

In Figure 1, reference numeral 2 designates a steel beam which is used to connect a cantilever plate 4 to a supporting structure 6, for example to a ceiling construction or floor construction. In order to minimize the heat flow from the supporting structure 6 to the outside of the building, i.e. to the concrete cantilever plate, insulation running transversely to the steel beam 2 is provided.

which is formed from a large number of cuboid-shaped insulating bodies 8. The insulating bodies 8 preferably have a rectangular cross-section and are made from a heat-insulating plastic foam. The steel beam 2 is used exclusively to absorb the tensile and compressive forces induced by the concrete cantilever plate 4 and to introduce these forces into the supporting structure 6, so that the insulating bodies 8 can be kept free of reinforcement. Depending on the length of the cantilever plate 4, two or more steel beams 2 are placed on a building wall 10.

placed as shown schematically in Figure 1. To simplify the precise installation of the steel beams 2 and the insulation 8, the steel beam has a sleeve 12 for installation, which is in the longitudinal direction of the

Steel beam 2 is fixed at a predetermined point. 35

\ For this purpose, the sleeve 12 cooperates with a truss web 1.8 connecting the lower chord 14 with the upper chord 16, which in the embodiment according to Figure 1 is formed by a wave-like bent rod.

fa The sleeve IZ has through holes 2 0 and 2 2 for the upper and lower chords. and also has a correspondingly shaped recess for a bar section 24 of the lattice web 18, whereby the sleeve 12 is fastened axially immovably to the steel girder 2 when attached.

It can be seen from Figure 1 that the sleeve 12 is designed as a stand and has a base for placing it on the building wall 10. In addition, the sleeve 12 has laterally protruding vertical stabilizing extensions 26 and a base-side stabilizing extension 28, so that in addition to an increase in the base area of the sleeve 12, a three-sided enclosure is formed for an insulating body 8 that can be inserted from above, which is necessarily aligned transversely to the longitudinal direction of the steel beam 2 after insertion.

Details of the structure of the steel girder shown in Figure 1 are explained in more detail below with reference to Figure 2. To simplify the description, those components that correspond to the elements already shown in Figure 1 are provided with identical reference numerals. It can be seen from this illustration that the upper girder 16 is formed by a steel rod with a circular cross-section. This also applies to the cross-section of the lower girder 14, which is bent at the ends in order to adapt its shape to the force curve in the cantilever plate and the supporting structure and to achieve a larger concrete cover in the end area, which also improves the force introduction. The lattice web 18 in the form of the wave-like

•&igr;

ti ■ · t

4 i « .

-9-

The bent rod is also formed by a steel round rod, which is alternately welded to the lower flange 14 in the area of the bends and to the upper flange 16 in the area of its rounded sections 30, 32 or end sections in such a way that a force is introduced from the lower flange into the web and the bending moments prevailing at the curved points of the lower flange are absorbed. The arrangement and design of the sleeve 12 is adapted to the vertical distance A _v between sub-

and top chord adapted so that at an inclination angle of

at least 45° the rounded sections 30 and 32 lie outside the sleeve 12. This means that the rounded sections of the lattice web 18 are all cast in concrete are so that the stresses on the truss web 18

be kept within permissible limits.

In order to obtain the width B,- and thus the thickness of the insulating body 8, the

welding between the truss bar 18 and the upper and lower chords at the side, whereby it is also possible to provide such a truss web 18 on both sides of the upper and lower chords.

(In the embodiment according to Figures 1 and 2, the lower chord 14 is designed to be shorter than the upper chord 16. In this way, it is very easy to provide transverse reinforcement below the upper chord 16 up to the front side the sleeve 12 or the insulating body 8 and a

further reinforcement in the plane of the lower flange 14 near to the sleeve 12 without having to work with individual rods. In this case, it is advantageous to cover the front end of the lower flange 14 with a plate 42 to safely transfer the compressive forces into the lower flange

14.

■ II
• f I

The other end of the lower chord 14 also carries a plate 40 in the embodiment according to Figures 1 and 2. This design of the inner region of the lower chord 14 is advantageous in order to facilitate a connection to a supporting structure using filigree prefabricated ceilings.

When assembling the steel beams 2, proceed as follows:

After '.TJ Arrange the reinforcements in a known manner

&Ggr;. the steel beams are fitted with a sleeve to the

Statics certain places on the building wall 10 vjrposi-

tioned, '-.-.for this purpose the steel beams already 15

with the cuff 12. Between The individual insulating bodies 8, which have previously been cut to length, are now inserted into the individual sleeves. Additional reinforcements are now added in the area

of the supporting structure, whereby it is on this 20

side, the reinforcement above the top flange

16, since the coverage in this area does not have to be so large.

Claims (9)

Shoe&egr;onSayings 1, A concrete cantilever slab having an upper chord (16) and a lower chord ( ¹¹ ) connected thereto via a lattice girder (IP) and having end plates ( 40, 42) enlarging the end faces of the latter, for a concrete cantilever slab which is connected to a supporting structure, such as a ceiling construction, with the interposition of insulation (8) running transversely to the steel girder, characterized in that the lower chord (14) is directed upwards at the ends towards the upper chord (16). 2. Connection element according to claim 1, characterized in that a sleeve (12) adapted to the cross-sectional shape of the insulation can be fastened to the framework web (18) for coupling an insulation carrier (8). 3. Connecting element according to claim 1, characterized in that the truss web (18) is a wave-like bent rod which is welded to the upper and lower chords. P/29 Telephone: 0 89-53 96 53 Telox: 5-24 845 tipat Fax: 0 89-53 73 77 Ores*«» BtS*. (Mönthen) K!o 3939 M< (BLZ 700 «00 00) IHnAtCh* Bank (Munich) Klo 7fl« 1080 (BU 700 700 10) Po<tgiro*fn1 (Manchen) KIo 670 "' »04 (Bt 7 700 100 80) rHE DAI ICHI KAMGYO BANK. Ir ¹ ITED (Munich) Klo 51042-33.007(BLZ 700 Tm 00) < Q_2_ % 4. Connection element according to claim 2, characterized in ■| characterized in that the truss web (18) is welded to the lower chord (14) at the curvature points of the latter. 5. Connection element according to claim 3 or 4, characterized ■ it is shown that the wave-shaped truss web ^ (18) is welded to the sides of the Gbsr and ünieri,?t, ■ ^wherein the curved sections (30, 32) of the truss web ^lie outside the sleeve (12). 6. Connecting element according to one of claims 1 to 5, characterized in that the lower flange (14) is shorter than the upper flange (16). 7. Connection element according to one of claims 1 to 6, characterized in that the cuff (12) is a two-part body whose halves (52a, 52b) are detachably connected to one another. 8. Connecting element according to claim 7, characterized in that the halves (12a, 12b) can be coupled by means of a snap connection. 9. Connection element according to one of claims 1 to 26 ' 8, characterized in that at least one end plate (40, 42) is provided in the region of its lower edge with a beveled surface facing the sleeve (12).