WO2012028293A2

WO2012028293A2 - Concrete component having an arrangement for load attachment and method for providing and planning an arrangement for load attachment

Info

Publication number: WO2012028293A2
Application number: PCT/EP2011/004352
Authority: WO
Inventors: Bernd SCHNÜTGEN; Wolfram Oertel
Original assignee: Areva Np Gmbh
Priority date: 2010-09-01
Filing date: 2011-08-30
Publication date: 2012-03-08
Also published as: DE102010036117A1; WO2012028293A3

Abstract

The invention relates to a concrete component (50) having a front face (52), in particular of an installation found in power plant and industrial construction. The component should have a versatile arrangement for load attachment, which can be set up with minimal effort. According to the invention said aim is achieved by an arrangement for load attachment comprising a plurality of anchors (2), wherein the anchors (2) are arranged on the front face (52) in a regular grid covering substantially the whole area and are embedded in the concrete component (50).

Description

description

Concrete component with a load attachment arrangement and method for providing and planning a load attachment arrangement

The invention relates to a concrete component with a front surface, in particular a reinforced concrete component of a plant of the power plant and industrial building (KIB), in this case a nuclear facility, with an arrangement for load attachment. It further relates to a method for providing such an arrangement and an associated planning method.

In the power plant and industrial construction (KIB), anchor plates are cast in as planned during the construction phase in order to absorb loads. To this anchor plates at a later time load receptacles are welded for the KIB expansion.

These can be load supports for cable trays, ducts for heating and ventilation, pipelines, etc.

If changes are necessary in the course of the further expansion of the system, be it through new cable routing, changes in cross sections or delays in planning etc., the originally intended and planned anchor plates can no longer or only to a limited extent be used. In this case, the subsequent installation of plates, especially dowels, is necessary.

Anchor plates consist of rectangular (in particular square) steel plates with anchors welded on the back, so-called head studs or Nelson bolts. The panels are installed, measured and fixed during the formwork and reinforcement work in order to prevent as far as possible displacement of the slabs during the concreting process. The back-welded anchors have the task to initiate the later acting on the plates forces in the corresponding component. Due to the special shape of the anchor, it is no longer possible to release the plates from the component when the calculated loads are maintained.

CONFIRMATION COPY The anchors are arranged in groups and available in different lengths, depending on the component thickness. Usually four anchors are arranged, with larger plates it can be up to 16 anchors.

Especially when used in nuclear facilities requires the installation of the plates due to the high reinforcement density a lot of effort. This is especially true if the anchor bolts of the various plates are not arranged in a uniform, even grid.

Dowel plates are retrofitted, dowelled plates that serve the same purpose as anchor plates; however, they can only absorb lower loads. The lower load bearing is due to the opposite dowel head bolts lower carrying capacity of the dowels for both tensile forces and shear stresses.

In safety-relevant components, so-called undercut anchors are used for the installation of dowel plates, which are subject to special requirements when used in nuclear facilities.

When installing dowel plates, certain distances to openings and anchor plates that have already been embedded in concrete must be taken into account. If these can not be adhered to, you may have to the receivable loads of the adjacent anchor plates are reduced accordingly.

The special procedure in the assembly of the plates results in an extremely high effort for their attachment due to the usually present high reinforcement density and the associated staggering of the reinforcement. An exact location of the deeper layers of the reinforcement is not always possible.

In the case of anchored anchor plates, there is also the problem that welding work must be carried out on the anchor plates for attaching loads. These welding operations lead to the following problems, which have not yet been satisfactorily solved: - Chemical modification of existing coatings on the free side as well as on the inaccessible side towards the concrete

- Execution of welding under relatively uncontrolled

site conditions

- Modification of the concrete component by high temperatures, especially in

contact area

- Modification of the concrete component by possibly required preheating

- Deformation of the anchor plates as a result of their heating and cooling with uncontrolled residual stress states, which can result in a significant reduction of the anchor load capacity

The invention is therefore based on the object to provide a concrete component with a flexible arrangement for load attachment, which can be built with little effort. Furthermore, a nuclear power plant with such concrete components and methods for providing and planning a load attachment arrangement are given.

With regard to the concrete component with a front surface, in particular a reinforced concrete wall of a power plant, the object is achieved with an arrangement for load attachment with a plurality of anchors, wherein the anchors arranged on the front surface substantially nationwide in a regular grid and embedded in the concrete component are.

Advantageous embodiments of the invention are the subject of the dependent claims.

The invention is based on the consideration that modern requirements in industrial and power plant construction, in particular in nuclear power plant construction, include flexible and needs-based load fastenings on concrete components. It is also based on the recognition that, during the design and production phase of the concrete components, future requirements for load attachment to these concrete components when placed in a core technical system is integrated, are difficult to predict. Therefore, pre-assembled anchor plates, or if necessary mountable dowel plates prove to be disadvantageous.

It would therefore be advantageous if a concrete component has a flexibly usable arrangement for load attachment, to which - depending on the need - without subsequent addition of other anchoring elements such as dowel plates, loads can be attached.

As has now been recognized, such a flexibly usable arrangement for load fastening can be achieved in that an area of a concrete component to which loads are to be fastened laterally, at least in the later accessible area, with a regular, preferably grid-shaped, arrangement provided by anchors. These anchors are thus embedded in the concrete component during the production of the concrete component.

Such a regular arrangement of anchors thus separates the processes of manufacturing the concrete component and planning the locations on the components to which loads are to be attached. Since the concrete components are essentially provided with anchors nationwide, can be decided individually, depending on the type and weight of the load, how many anchors are to be used for their attachment.

In addition, the position on the component can also be chosen essentially freely, given a sufficiently narrow grid. Consideration of previously cast-in anchoring structures, such as anchor plates, must therefore not be taken.

Since the anchors are already incorporated throughout the production phase in the concrete components, there is no need to subsequently install dowel plates, which optionally collide with the position of the reinforcement.

Depending on the type of load to be fastened, the number of anchors that should carry this load can be selected. For this example, plates, in particular anchor plates are attached to a previously selected number of anchors. These plates can then be connected to the load to be fastened. In a preferred embodiment, the concrete component is provided with a reinforcement, wherein the anchors are arranged in the interstices of the reinforcement. Such an embodiment of the concrete component is easy to achieve, since both the reinforcement and the anchor can be planned and installed during the production process of the concrete components.

Advantageously, the anchors, in particular as non-positive anchors, in the manner of Kopfbolzdüblen or in the manner of reinforcing bars with an upset head performed at one end, the anchor having an accessible from the front surface of the concrete component external or internal thread. The accessible front surface of the anchor is preferably aligned flush with the front surface of the concrete component. Alternatively, the anchors may also protrude out of the surface. With the external or internal thread other components such as anchor plates can be screwed. These can then be connected to the load to be fastened, for example, welded.

In a further advantageous embodiment, the concrete component has a rear surface. At least one anchor penetrates the concrete component from the front surface to the rear surface and has an accessible from the rear surface of the concrete component external or internal thread. In this way, stable and water-impermeable overstresses are realized by the concrete component. Such a concrete component thus has both on the front and on the rear surface on a regular or regular grid of anchors, the grid spacings are the same size in both cases.

Advantageously, the anchors are arranged in a grid of 15 x 15 cm. Such a grid allows a close-meshed reinforcement and allows high flexibility in terms of load application. Advantageously, the concrete component may comprise a number of anchor plates, each screwed to a plurality of anchors. The anchor plates can vary in size and in terms of the number of anchors with which they are bolted. With regard to the use in a nuclear installation, the above-mentioned object is achieved with at least one such concrete component. Usually a nuclear installation will comprise a plurality of such concrete components. If it is already clear in the planning and production of a concrete component at which point of the nuclear installation it will be installed, the area-wide grid can be limited to the accessible front surface or, in the case of the passing anchors, to the two accessible areas. That is, the majority of the anchors is arranged area-wide in the later accessible area in a regular grid.

With regard to the method for providing a load-fastening arrangement with a plurality of anchors in a concrete component having a front surface, the above-mentioned object is achieved according to the invention by inserting the anchors on the front surface into the concrete component across the entire surface in a regular pattern. Advantageously, in a concrete component having a reinforcement, the anchor is embedded in the interstices of the reinforcement.

With regard to the method for planning an arrangement for load attachment and a reinforcement in a concrete component, the abovementioned object is achieved according to the invention by generating a common installation plan for a reinforcement and an associated grid of anchors by means of a CAD program running on a computer. Instead of a CAD program, another program can be used, by means of which a geometric and quantitative design of a concrete component with arrangement for load attachment and reinforcement is possible.

Reinforcement and anchor arrangement can be coordinated in this way in optimized form. On the one hand, the program can allow manual input through which the reinforcement and anchor arrangement can be specified. On the other hand, the program can also perform certain steps in an automated or automatically running form independently. For example, when specifying a reinforcement and possibly a catalog of requirements to the grid of anchors, the program independently suggest a grid or set, which can still be adjusted manually if necessary. During the planning phase, the common layout plan is advantageously displayed on a display. A joint installation plan generated in this way can be printed or displayed on the one hand, on the other hand, it can be transmitted directly to the production facility. The possibility of planning a joint installation plan also makes it possible to create a database in which different joint installation plans are stored for concrete components with different application area or requirement profile and can be recalled at a later time. These measures allow a time- and resource-saving planning of any system in the KIB area, in particular nuclear installations, in which subsequent improvements regarding the possibility of load attachment are avoided.

The advantages of the invention are in particular that a flexible Erstbefestigung is made possible by a nationwide and arranged in a regular grid plurality of anchors in a concrete component. Accordingly, when producing the concrete component, it is not yet necessary to provide the information on which points of the concrete component later loads are to be fastened. As a result, an attachment of anchor plates to still free anchors is possible at a later date. Since the anchors are arranged in a grid pattern, any missing or "forgotten" anchors in the grid can be easily detected and supplemented before concreting.

The concrete component according to the invention allows a high utilization of the anchorages by the anchor can be performed in extreme cases to the opposite side of the concrete component. As a result, waterproof overstresses of the concrete component can be realized with relatively little effort. Due to the essentially comprehensive arrangement of the anchors, the complete concrete component can be used for load fastening if required.

An embodiment of the invention will be explained in more detail with reference to a drawing. In it show in a highly schematic representation: 1 is a trained as a dowel anchor anchor for use in a load attachment arrangement in a concrete component with a head and an internal thread,

FIG. 2 shows a bolt designed as a headed bolt for use in a load securing arrangement in a concrete component; FIG. in contrast to FIG. 1, made of corrugated reinforcing steel, with an external thread and an upset head,

Figure 3 is an anchor designed as a head bolt for use in a load-securing arrangement in a concrete component with an internal thread. in contrast to FIG. 1 produced from ribbed reinforcing steel and with upset head,

Fig. 4 is a waterproof execution of a head bolt with two thickening parts for

Throughput of a concrete component, and

5 shows a concrete component with a reinforcement and with an arrangement of anchors according to FIG. 1.

The same parts are provided in all figures with the same reference numerals.

FIG. 1 shows an armature 2 made of semifinished product or cast iron for use in the arrangement for load fastening in a concrete component according to the invention. The armature 2 comprises a shank 8 of semi-finished or cast iron, which is provided at one end with a head 14 or collar. At its other end, the shank 8 is provided with a conical intermediate piece 20, to which a thickening part 26 adjoins. The thickening part 26 is designed to be substantially axially symmetrical and cylindrical. The thickening part 26 has an internal thread 32, which is designed as an axial threaded bore. Due to the design of the armature 2 with shaft 8, head 14, and intermediate part 20 and thickening part 26 of the anchor is designed to accommodate both high axial and high radial forces and to transfer to the surrounding concrete component or dissipate. Advantageously, the anchor 2 is completely embedded in the concrete component, so that the outer end of the thickening member 26 does not protrude. At the internal thread 32 can be screwed designed for load bearing anchor plates. Depending on the size of the anchor plate more or less anchor 2 can be used for their attachment. The load transfer between the anchor plates and the anchors anchored takes place, as stated above, via screw.

Here, both preloaded and unbiased screws can be used. The carrying capacity of the anchors 2 is to be expected because of the similar head formation in the same order of magnitude as Nelson bolts. The shear resistance should exceed that of conventional head bolt anchors or Nelson bolts, since the threaded sleeve has a larger diameter. A special case occurs with preloaded screw connections. Here, the friction between concrete and slab is activated and used for load transfer for shear forces.

The anchor 2 shown in Fig. 2 has a shaft 8, which is made of ribbed reinforcing steel (which is approved for the corresponding construction project) with ribs 10. This anchor 2 has an upturned to the shaft 8 head 14 and an external thread 33. Fig. 3 also shows an anchor 2 with a shaft 8 made of reinforcing steel and an upset head 14, which has an internal thread 32 in contrast to the anchor 2 shown in Fig. 2. Both anchors 2 are suitable for use in a component 50 according to the invention.

A watertight embodiment of an anchor 2 penetrating a concrete component 50 between a front surface 52 and a rear surface 54 is shown in FIG. The armature 2 or anchor bolt illustrated in FIG. 4 comprises in the center a metal disk 38 which to a certain extent replaces the head 14 of the embodiment of the armature 2 shown in FIG. Mirror-symmetrical to the central disk 38, the armature 2 comprises in each case a shaft 8, intermediate part 20, and thickening part 26, which can each be embodied as in FIG. Both halves of the armature 2 are rigidly connected. Ideally, the armature 2 is made in one piece and is made of an integral construction of a made of a common semi-finished or cast in one piece. At both ends of the armature 2 is each equipped with an internal thread 32. The material used for the anchors can be any steels approved for the particular application.

An inventive concrete component 50 in plan view of the front surface 52 is shown in Fig. 5. The concrete component 50 includes a latticed reinforcement 56. In the middle of the interstices of the reinforcement 56, the anchor 2 are embedded in the concrete component 50. Fig. 5 shows substantially a section of a concrete component 50. That is, both the reinforcement 56 and the grid of anchors 2 extend in all directions to the edge not shown here or to the outer enclosure of the concrete component. The arrangement of the armature 2 is substantially embedded throughout the concrete component 50, at least in the later accessible after completion of the building area.

The comprehensive embedding of anchors 2 in a concrete component 50 results, inter alia, in the following advantages: During the final load application, no welding work on concrete is necessary. As anchors 2 and not anchor plates are embedded in the concrete, air pockets under anchor plates are avoided during the concreting process. As stated above, the concrete component allows a flexible design of mounting options for loads by the rastered attachment of the head bolt dowels.

For design changes in which loads are to be applied to other, different locations, or additional need for previously unscheduled mounting options, these needs can be met simply by additionally attaching anchor plates and / or replacing anchor plates. Since the anchors 2 are embedded in concrete in the concrete component 50, a search for gaps in the reinforcement in subsequent attachment of load fasteners is not necessary.

Since the anchors 2 are already inserted into the concrete component 50 during the concreting process, there is no risk of (subsequent) damage to the reinforcement. Since the anchor plates or plates are bolted to the anchors 2, these plates can be easily removed and replaced by other plates. The size of the plates can therefore be changed later.

Furthermore, load tables are available for quick dimensioning and simplified verification of the anchors. Depending on the concrete quality (compressive strength class as the main criterion) and the permissible thread size (depending on the diameter used), the permissible loads can be read from load tables. The preparation of the tables is preceded by a corresponding static calculation.

Different anchor lengths are possible in the concrete component 50 according to the invention, so that no back anchoring by means of reinforcement is required. In addition, a simplified formwork construction results. The simplified formwork construction is due to the elimination of any surveying work in the installation of anchor plates. Anchor plates usually need to be attached to the reinforcement and calibrated, but in exceptional cases, the anchor plates are attached to the formwork elements before the elements are placed. Often, however, the anchor bolts come into conflict with the close-meshed reinforcement net. According to the invention, however, no additional cones are necessary, and an execution of the anchor 2 in stainless steel is possible (this is particularly important for components with corrosion potential). The concrete component 50 allows a simplified dismantling of the formwork used, and the anchor 2 are also suitable for working joints as a reinforcement connection. In the event that additional concrete components must be arranged, free, unoccupied anchors can be used as reinforcement connections. In this case, rebars, provided with a matching external thread, screwed into the threads of the cast-anchor. At this iron then the other required reinforcement is attached. This must be done taking into account the necessary concrete coverings and edge distances. LIST OF REFERENCE NUMBERS

anchor

shaft

Ripping the rebar

head

intermediate part

thickening part

inner thread

external thread

center disc

concrete component

front surface

posterior surface

reinforcement

Claims

claims

A concrete component (50) having a front surface (52), in particular a reinforced concrete component of a plant of power plant and industrial construction, with an arrangement for load fastening with a plurality of anchors (2), the anchors (2) on the front surface (52) are arranged substantially area-wide in a regular grid and embedded in the concrete component (50).

2. concrete component (50) according to claim 1, which is equipped with a reinforcement (56), wherein the armature (2) in the interstices of the reinforcement (56) are arranged. O

3. concrete component (50) according to claim 1 or 2, wherein the armature (2) as a bolt, in particular in the manner of head bolt dowels are executed, and wherein the bolt from the front surface (52) of the concrete component (52) accessible outside ( 33) - or internal thread (32).

4. Concrete member (50) according to claim 3 having a rear surface (54), at least 5 an anchor (2) the concrete component (50) from the front surface (52) to the rear surface

(54) and having a of the rear surface (54) of the concrete component (50) accessible external (33) - or internal thread (32).

5. concrete component (50) according to one of claims 1 to 4, wherein the armature (2) in one

Grid of 15 * 15 cm are arranged. 0 6. Concrete component (50) according to any one of claims 1 to 5, with a number of anchor plates, each bolted to a plurality of anchors (2).

7. Nuclear plant with at least one concrete component (50) according to one of claims 1 to 6.

8. A method for providing a load-securing arrangement comprising a plurality of anchors (2) in a concrete component (50) having a front surface (52), in particular a reinforced concrete component of a nuclear installation, wherein the anchors (2) are embedded on the front surface (52) over the entire area in a regular grid in the concrete component (50).

9. The method of claim 8 with a concrete component (50) having a reinforcement (56), wherein the armature (2) in the interstices of the reinforcement (56) are embedded.

A method for planning a load attachment assembly and a reinforcement in a concrete component (50), wherein a common deployment plan for a reinforcement (56) and associated rasterization of anchors (2) is generated by means of a computer program running CAD program.