DE1812865C3 - Reinforcement for flat concrete components - Google Patents

Description

The invention relates to a reinforcement for flat concrete component, consisting of reinforcement mats and allowances in the form of narrow mat tires.

Flat bcionbaulcilc. like / .. B. ceiling tiles, can reinforced with individual steel bars or with reinforcement mesh. In the case of reinforcement from individual bars it is possible to convert the required steel cross-sections determined in the static calculation into to represent the whole variety with any precision. To achieve a certain steel cross section only the distances between the individual rods of the same diameter need to be reduced or increased to become. If reducing or increasing the spacing is not sensible or not possible, then bars of different diameters can also be arranged. This means that every component can be static and are properly reinforced structurally. However, reinforcement from single rods has the disadvantage of one thing a lot of work, because each individual rod has to be prepared and installed for itself.

The second possibility for the reinforcement of flat concrete components consists in the use of Reinforcement materials. These mats have two sets of bars crossing each other at right angles - lengthways rods and cross rods - which at the intersection points i are mostly allied to one another by point welding. For reasons, "those with the manufacture and the Transport of these Malten are related, they can not be made in any dimensions So you have to reinforce a component nc next to each other and with one to transfer the bar Forces necessary mutual overlap are laid. This overlap is called al; Push.

The advantage of this type of reinforcement lies in this. that large-area reinforcement units are made to measure can be produced economically. Since the work steps necessary for cinei reinforcement with individual bars ge, such as bending, precise laying out and linking, are omitted, reinforcement meshes can be installed quickly and easily. The rigid connection of the longitudinal and Cross bars in the welding points also create an excellent bond between the reinforcement and concrete.

However, a certain rigidity is associated with the mentioned advantages of reinforcement made of mats. The steel cross-section of the longitudinal and transverse rods per unit of width must namely vorbestimpit for prefabrication be, both in terms of the distances between the individual rods and in terms of the available diameter. Under consideration of the wire industry offered In the course of the years, there has been a standardization of the distances between the rods, in such a way that that only distances of 50 mm and a multiple thereof and 75 mm and a multiple thereof are used will. The choice of the distances is further restricted by the fact that supporting bars only have one maximum distance of 200 mm from each other and cross bars 333 mm from each other to be allowed to.

Under these conditions, for example, a cross-sectional area of 0.84 to 7.54 cm ² per meter of width can be represented by 18 different types of mat. In order to enlarge the cross-sectional area, double bars consisting of two bars arranged close to one another were used in the past, whereby the cross-sectional area was extended to 15.08 cm ² per meter width and the number of types to 2 · 18 = 36.

The variety of May types and the multitude of to The rod diameters required for their production influence the production costs of the reinforcement mesh very essential. Furthermore, this multitude stands in the way of the automation to be striven for in production. The share of the total costs that has to be spent on storage and stock keeping is also considerable.

Nevertheless, even the mentioned number of 3b different types of mats is sufficient for the construction economic reinforcement in practice is not sufficient in many cases. Therefore one often uses two Layers of reinforcement mats on top of one another in order to double the available chair sections and to achieve further cross-sections by combining different types in order to reduce the differences between two successive cross-sections. Through these measures but the costs for the laying of the Malten are significantly increased.

To remedy the disadvantage that, for example, at

"Concrete slab with a parabolic momeiiien-

elution of the in Fcldmiite for the maximum Bicgcmo-

t required Siahlquerschniu also in full size

R ^1C "can be carried out to the bottom of the plait

R where in this size it is no longer crfor-Hriich would be, you have a so-called staggered

used. Here, the respective / ^C wide * (j of Bcwehrungsmattcn is arranged the Momentcnverlauf ^ rnrcchcnd shortened This measure ^C "l ip vird but the number of different Maltenty -". "" N undi -grölicn further increased so that the amount of work and the Need for mats at the construction site

increase.
Another problem with reinforcement with

smatten _{! jcgl} J ₁₁₁ -J _n that these must be laid with a mutual cover to secure the power transmission. If the individual reinforcements have flat bars up to their edges! then the longitudinal bars are inevitably present twice in the covering areas. This leads to a certain excess of steel which, because of the large distance between these areas, which corresponds to the respective mesh width, cannot be thought of as being equally distributed over the entire width of the reinforcement.

Various proposals have also become known. _{in order} to avoid the excess cross-section present in the overdeveloped areas. A well-known suggestion is that in the edge areas across the width of the cover area, only LHn ^ ssiäbc are arranged, the cross-section of which is half as large as that of the bars in the inner mat area '(German Patent 9 73 001). In this way, by using two longitudinal bars of half cross-section one above the other in a covering joint, a cross-section corresponding to a normal cross-section is achieved and a reinforcement line that is uniform over the entire width of the reinforcement is achieved.

Another unpublished proposal (German Auslcgeschrifl 12 90 322) is that / wipe the covering loops of two mats to create reinforcement clusters inside Mat area, preferably in the middle of the painting. additional Mat strips are arranged, the rods of which correspond to the surplus rods in the covering areas correspond. In this proposal, the narrow mat strips only serve to cover the entire width of the mat To achieve a uniform reinforcement intensity that is equal to the required steel cross-section.

It is also a method of reinforcing Concrete has become known using reinforcement paints (Austrian patent 2 38 919). where undersized reinforcement meshes are used and the steel cross-section required to adapt to the torque curve ic unit length loose addition of Suihlstäben with an increased one Hard strength wedge ensuring surface is achieved. This is essentially also about the staggered reinforcement already mentioned, with the additional disadvantage that some are loose Stahlstäbc laid and to the bars of the reinforcement maiten angerödeli have to graze in order to avoid shifting the same when pouring the concrete. Since the loosely attached safety sticks do not interfere with the other Rods are welded, they must not be used with the same steel tensions, what results in further difficulties with regard to the static calculation.

Finally, in connection with a reinforcement element, the cross bars or cross pieces welded on to improve the anchoring effect has become known (FR-PS 14 37 626) for the local reinforcement of a reinforcement wall existing reinforcement narrow, mat-like Use strips of different lengths. crossing each other at right angles above and below the level reinforcement are arranged. The anchoring effect of this reinforcement element is improved exploited, since a local reinforcement of a mesh reinforcement cannot be avoided lets the allowances end in the train area.

The invention is based on the object of creating a way to take advantage of the prefabricated To link mesh reinforcement with those of the versatile, variable individual shielding and at the same time to avoid the disadvantages inherent in these forms of reinforcement.

The invention solves this problem with a method according to the invention Reinforcement in that the narrow mat strips are made up of at least two connected by transverse wires Longitudinal bars are arranged at such intervals that one over the entire width of the reinforcement the same reinforcement intensity is effective and that the reinforcement portion of the mats including any useful as an evenly distributed accumulation of reinforcement their overlap areas is less than the maximum required reinforcement.

The reinforcement malls can be designed on the edge as in their central part. But you can Form a steel cross-section that is constant over the entire width of the reinforcement, also as a result of the reduction in the cross-section at the edges, with between two overlap areas at least two strips of material are arranged and the distance between the Longitudinal center lines of the outermost strips in each case half of the longitudinal center lines of the overlap areas is as large as the center-to-center distance between the strips.

The narrow mat strips can also be used in both The support strings of the component to be reinforced can each be arranged over one another.

Finally, the distances between the longitudinal center lines the matting lines are integral multiples of the distances be the bars of the reinforcement malls.

The advantage of the reinforcement arrangement according to the invention is primarily to be seen in the fact that the in the In the lower (first) layer, the reinforcement meshes laid only the cross-section elements that form the basic reinforcement that must go through from support to support in order to reinforce a component. while with the upper (second), from the narrow material tires formed position of the respectively required cross-section is achieved. With the arrangement of a second layer narrow matte tires can vary depending on the number and spacing the same a large number of reinforcement cross-sections up to twice the value of the cross-section the first layer of a base mat type can be achieved. By dividing the reinforcement cross-section in two In a basic reinforcement and an additional reinforcement from narrow material sections, not only is the combination possible expanded and thus reduced the number of mallcmypcn to be kept in stock, but also simplifies the manufacture and storage of the mats. So can succeed with a number of Matienypes of conventional kind and at most the »! • tii-hnn uprinsTL-n number of Streil'typen a Quci-

same small number of sireil types a cross

Sehnittsbercieh from about 1.0 to 45.0cm- / m covered will.

The particular advantages of the new reinforcement arrangement result from the following consideration:

If, for example, with known reinforcement mats for a cross-section range of 0.92 to 22.62 cni ² / m for reinforcing uniaxially reinforced components, 24 different types of mesh are required, then these 24 may have 24 different cross-sections. However, since the required steel cross-sections are only rarely the same as the predetermined cross-sectional series and under-reinforcement is not justifiable for reasons of stability of the structures, over-reinforcement cannot be avoided. This additional consumption due to over-reinforcement fluctuates between 10 and 20% with the maize systems known today.

According to the invention, only 6 types of mat are commercially available in order to achieve the same cross section Type and 5 types of mat structure required. With these 6 types of mats and 5 strips, for example at intervals of 1.0: 0.90: 0.80: 0.70: 0.60 and 0.50 in are distributed over the entire width of the reinforcement, 6 · 6 · 5 = 180 different cross-sections can be achieved. While for the standard mat program 18 different rod diameters are required for the reinforcement according to the invention only 6 different bar diameters are required, as the basic reinforcement mesh types are the same Bars can exist like the strip types of the additional reinforcement.

Another advantage of combining a conventional type of closed basic reinforcement with a Additional reinforcement in the form of narrow matt strips lies in the fact that the added strips both as well as Previously common for mesh reinforcements, they can end in the area of tensile stresses, with the course the bending moment are arranged in a correspondingly shortened manner, as well as, as has so far only been the case with individual bar reinforcements was possible. can be bent up. This means that the staggered reinforcement is used of reinforcement paintings can also be used for all areas, in which they have so far not been able to be accommodated due to the size of the expected reinforcement meshes Shear stress was not possible. Namely, those in the tensile stress range cannot do this more required reinforcement parts of the strips Bending is anchored in the compressive stress area and for plates that run through several fields Absorption of the negative bending moments in the support area can be used.

Another problem is that. it depends on a component is to be reinforced uniaxially or biaxially. different proportions of distribution reinforcement are available must be. The minimum amount of distributor bracing for uniaxially clamped panels is 20% of the structure of the load-bearing reinforcement. To also Intermediate values up to biaxially tensioned slabs with 100 "/ (I can implement reinforcement / u can, different types of matting are produced, for which about 40, 60, 80 and 100% of the respective steel cross-section the longitudinal bars are provided as Vcrtcilcrbewchrung. This increases the variety of stocks holding mat types increased even further.

Mh let the inventive reinforcement against it do not deal with the already mentioned 6 different types of mats and the 5 different types of strips only in one, but also in two perpendicular l <iihiunj.'cn hclicbiL-f StahkiiierschniHi; achieve.

Further advantageous properties of the invention emerge from the following description of the in Exemplary embodiments shown in the drawings. It shows

F i g. 1 shows a schematic cross section through a reinforcement according to the invention using FIG Reinforcement meshes with reduced cross-sections at the edges,

F i g. 2a to 2f cross sections through according to the invention

ίο trained narrow mat strips,

I i g. 3 and 4 different in schematic representation Possibilities for arranging narrow mat strips with regard to the basic reinforcement.

In Fig. 1 shows an application example of the reinforcement according to the invention on the basis of a detail from a cross section through a concrete slab. The reinforcement mats 1 consist of cross bars 2 and longitudinal bars 3; the latter have the same diameter over almost the entire width of the mat and are spaced apart ; i.

In the edge areas of the mats 1 are on the width of the respective cover area l.ängsstänke 4 arranged, the cross-section of which is about half as large like that of the Eängsstäbc 3 in the rest of the mat area. In this way, the basic reinforcement becomes even across the joint area Reinforcement intensity reached.

In addition to the basic reinforcement consisting of Malten 1 two mat strips 5 are arranged. Here are the distances between the longitudinal center lines of the strips 5 from the longitudinal center line of the shock area approximately half as large as the distance between the longitudinal center lines of the matte circles from one another. As a result, the cross sections are accumulated arranged at regular intervals so that the arithmetical distribution of the additional cross-section created by the steel accumulations over the entire width of the reinforcement is.

In Fig. 2 shows various exemplary embodiments of mat strips to be used in the reinforcement arrangement according to the invention. The strip 6 in FIG. 2a consists of two longitudinal rods 8. which are spaced b from one another. The longitudinal bars 8 are connected to one another by transverse wires 9. This connection can be made by spot welding. be done by clamping or by plastic.

As the F i g. 2b and 2c show one can or can both longitudinal rods 8 be designed as double rods. Finally you can use the same width of the mat strip also three, four or five longitudinal bars 8 in front be at hand. The distance between the outermost longitudinal bars ί is at least 200 mm (Fig. 2d to 2f).

In the F i g. 3 and 4 show some more examples of how the mat strips look like:

the width of the reinforcement mats resulting joint distance can be arranged.-Fi g. 3a shows the basic movement from mats 11 in which a normally unusable pile of slabs arises in the joint. The distance between the center lines of the joint areas is denoted by J, in FIG. 3b, in the area between the joints, there are two mat strips 12, which produce a steel cross-section that exceeds the base cross-section and is evenly distributed over the entire width of the reinforcement. The spacing changes as the number of mats increases, each strip consisting of ¹ AS or '/ -, .V (Figs. 3c and 3d).

F i g. 4 shows one of the FIGS. 3 similar illustration ii Connection with malls, where in Slolibereic

no steel build-up occurs. The paintwork of the basic reinforcement (Fig. 4a) are denoted by 13 here. The basic reinforcement is shown in FIG. 4b two mat strips 12 placed, which have a distance from the Sioßbcreich that is half the distance between the strips 12 among each other. As a result, based on the gan

ze protection width c. those generated by the strips alone Cross-section increases at equal intervals from each other. This arrangement can also be varied with three or four added mat strips (Figs. 4c and 4d).

For this purpose 2 sheets of drawings

Claims (6)

Patent claims: 1. Reinforcement for flat concrete components, consisting of reinforcement mats and supplements in the form of narrow mat strips, characterized in that the narrow mat strips of at least two longitudinal bars connected by Qiierdrraht are arranged at such intervals that an equal reinforcement intensity is effective over the entire width of the reinforcement and that the Reinforcement component of the mesh including any reinforcement used as evenly distributed ^{: the} accumulation of their overlapping areas is less than the maximum required reinforcement. 2. Reinforcement according to claim 1, characterized in that that the reinforcement meshes are designed at the edge as in their middle part. 3. Reinforcement according to claim 1, characterized in that that the reinforcement meshes due to edge weakening after laying one over the the entire width of the reinforcement form a constant cross-section and that between two cover areas at least two mat strips are arranged, the distance between the longitudinal center lines the outermost strips of the longitudinal center lines of the overlap areas are half as large is like the distance between the centers of the strips. 4. Reinforcement according to one of claims 1 to J, characterized in that the narrow mat strips in both load-bearing directions of the structural element to be reinforced, each arranged overlapping one another are. 5. Reinforcement according to one of claims I to 4, characterized in that the distances of the Longitudinal center lines of the mesh strips are integral multiples of the bar spacing of the reinforcement material are. 6. Reinforcement according to one of claims I to 5, characterized in that bent-up mat strips are used.