EP3719229B1

EP3719229B1 - Concrete floor panel, method of production of such panel and floor made of this panel

Info

Publication number: EP3719229B1
Application number: EP20162681.9A
Authority: EP
Inventors: Krzysztof Lis
Original assignee: Individual
Current assignee: Individual
Priority date: 2019-04-01
Filing date: 2020-03-12
Publication date: 2022-12-28
Anticipated expiration: 2040-03-12
Also published as: PL245156B1; PL429472A1; EP3719229A9; EP3719229A1

Description

The object of the invention is a concrete floor panel and the method of production of such panel. The object of the invention is also a floor made of these concrete panels.
In residential and industrial construction, ceilings made of reinforced concrete floor beams and hollow bricks embedded between them are popular. The hollow bricks can be made of ceramics, concrete and gravel, concrete and slag, concrete and rubble, lightweight concrete, foamed polystyrene, gypsum. Reinforced concrete beams protect the hollow bricks against damage and are an underlay for the floor. The structure made of beams and hollow bricks is poured with a layer of concrete topping, which covers the hollow bricks and fills the empty spaces between them and the beams.
The greatest disadvantage of solution of this type is time and labour consumption on the construction site due to the required laying of hollow blocks. For example, per 100m² of beam and block floor approx. 700 elements, hollow blocks with dimensions of 25 x 50 cm and an average weight of 15 kg carried manually by the workers have to be laid on a 100 m² densely ribbed ceiling. A formwork is also necessary.
The next generation of floors is presented by Filigree slabs. It is a stay-in-place formwork slab comprising longitudinal and transverse supporting reinforcement and sunken trusses allowing transport of slabs. Such slabs had to be individually designed for the building dimension. In addition, if the slab had a defect, it had to be made again. Filigree slabs could not be cut on site and their size required heavy equipment both in production and on site.
Due to the disadvantages of Filigree slabs, similar slabs were developed, but with smaller dimensions. This made it easier to manufacture, storage, transport and production of floors using such prefabricated elements.
The second trend in the development of floor manufacturing techniques is the production of such prefabricated elements which will provide them with thermal and sound insulation properties. Such slabs usually include a reinforced structure on which relatively lightweight/foam blocks of the hollow block type are placed.
For example, floor system according to the well-known Master product on the market: http://www.konbet.com.pl/System_stropowy_MASTER,1722.html refers to a system comprising prestressed concrete beams responsible for the floor bearing capacity and dedicated floor hollow blocks, on the basis of which systems of various heights and spans can be built. The hollow bricks can be 3-chamber expanded clay aggregate concrete block, concrete, concrete and gravel and 5-chamber expanded clay aggregate concrete block - this hollow brick has the so-called upper shelf, this means that at 24 cm of the floor, it does not requires additional concrete topping and has additional thermal insulation parameters.
From document EP2189427 (B1 ) a lightweight concrete structure containing at least one layer of prefabricated lightweight concrete slab attached to a reinforced frame structure is known. The spaces between the skeleton construction elements are at least partly filled with mortar containing foamed polystyrene and cement with specific characteristics, also containing foamed polystyrene. The structure in turn assumes the use of a material: wood or metal.
Application DE2550324 (A1 ) discloses a floor element for roofs, ceilings and walls with a hollow frame formed by reinforced concrete longitudinal and transverse ribs as a support for part of the slab. It has a layer of plain concrete at least on the underside of the frame and a light filling between the ribs. It is therefore a two-way reinforced concrete slab with dimensions preferably approx. 2.5 x 7.5 m. To insert a light filling between the ribs, the concrete structure must be made in advance and wait until the concrete hardens. Then, take off the formwork and pour the created spaces with light material. It is a very labour and time-consuming method - it takes up to 1-2 days for the concrete to dry. In addition, it is impossible to achieve a permanent bond between lightweight material and plain concrete.
KR 2016 0039855 A discloses a concrete floor panel according to the preamble of independent claim 1. Due to the disadvantages of solutions known in the state of the art, it is necessary to look for new floor slabs that meet the disadvantages of solutions from the state of the art. The technical problem that the present invention solves is therefore to provide a concrete panel for the production of floors, which can be made quickly, with low labour consumption, which can be prepared in almost any size on request, and at the same time ensuring easy production of a floor which will have a load-bearing capacity appropriate for floors and will also exhibit thermal and sound insulation properties. Providing such a slab requires the use of special manufacturing technology.
The object of the invention is a concrete floor panel according to independent claim 1 consisting of a structure made of plain concrete with reinforcement sunk inside and a part of lighter material than plain concrete, characterized in that the concrete structure consists of:

plain concrete slab where the reinforcement is in the form of prestressing elements, and
at least two plain concrete beams placed on the slab,

Preferably, the concrete floor panel is characterized in that the prestressing elements are lines or prestressing wires.
Also, preferably, when the concrete floor panel is characterized in that two concrete beams are placed on the slab. Preferably, the concrete beams are placed on the slab symmetrically and parallel to each other and to the panel edges.
The material lighter than plain concrete is lightweight concrete selected from polystyrene concrete, perlite concrete, expanded clay concrete, aerated concrete, foam concrete. Also, preferably, the material lighter than plain concrete is polystyrene concrete made of regranulate constituting shot-blasted recycled polystyrene.
The invention also relates to a method of production the concrete floor panel according to independent claim 6, comprising the steps of:

a. making a structure of plain concrete containing sunk inside reinforcement using a slip method with a slipformer type device, where a slab made of plain concrete in the compressed concrete technology is produced in the first place, where prestressing elements are used as reinforcement, on which at least two beams (5) of plain concrete are formed,
b. injection into at least one of the first spaces designated on the slab by at least two beams of lighter material than plain concrete,

The subject of the invention is also a floor comprising the stacked concrete floor panels described above poured with concrete topping.
The panel slab should preferably be relatively narrow, in the range of 30-100 cm. With larger slab widths the panel could crack.
The spacing of the beams on the slab creates an asymmetrical spatial arrangement - when the panels are stacked, inter-beam spaces are obtained: one wider (in the case of two parallel beams - the first space), e.g. preferably 25 cm width filled with a lighter material than plain concrete and a second space with a width of e.g. 15 cm, a hollow space which is filled on the construction site with concrete topping (structural concrete). In the second space, it is possible to add a supporting or other shear reinforcement.
Part of the material lighter than plain concrete can be made using recycled material. An example of such a material lighter than plain concrete is shot blasted polystyrene. A positive aspect of the invention is then the use of recycled materials, which is a desirable ecological aspect for the production of the panel according to the invention.
Preferably, on the arranged panels according to the invention, separating and supporting reinforcement can be placed. According to the standards, separating and supporting reinforcement should be used in all types of floors, especially for large spans.
The invention as described herein, eliminates the disadvantages of prior art floor systems. First of all, the slabs and the floor themselves are characterized by low weight due to the material used to fill the space between the beams. The low weight of the slab makes it easy to transport and assemble. In turn, the low weight of the floor reduces the amount of steel used in the structure of the floor and reduces the load on walls and foundations, which allows reducing their load capacity or thickness.
By changing, for example, 1 m³ of structural concrete, which weighs approx. 2400 kg/m³, for lightweight concrete, which weighs approx. 200 kg/1m³, a floor of about 20% lighter and warmer at the same time, can be obtained.
However, despite the low weight of the panel, it provides adequate floor load-bearing capacity due to the use of string or prestressing wire reinforcements found in both the slab and concrete beams, which in turn also reinforce the structure.
The panel according to the invention - in contrast to the state of the art solutions - has no transverse reinforcement sunk in the structure of plain concrete.
The use of a material lighter than concrete in the production of a floor panel, preferably cement-polystyrene mortar, provides the floor, according to the invention, with high sound insulation and thermal insulation.
The use of ready-made concrete panels in the production of the floor results in low consumption of concrete at the construction site (concrete topping), very low labour consumption, a small number of props, fast assembly, high standardization, modularity.
The panel according to the invention therefore has the following advantages over the panels and floors made of them known in the art:

significantly increases the thermal insulation of the floor,
significantly reduces the weight of the floor,
reduces the number of supports to a minimum, and for small spans up to 4 m, completely eliminates the need for mounting supports,
increases the load capacity of the floor,
reduces the consumption of scarce materials and raw materials such as sand, gravel, cement,
reduces the consumption of concrete poured at the construction site,
reduces transport costs, reduces the labour consumption of the floor production at the construction site.

A new method was used in the technology of producing the concrete floor panel. It is a method combining the known sliding method of making a slab of plain concrete and then beams of plain concrete. This step of work is performed with a "slipformer" type device. Then, to produce the panel according to the invention, a lighter material than plain concrete must be injected between at least two beams of plain concrete. In order to obtain a permanent connection between plain concrete and a lighter material than concrete, the injection is made during casting (panel injection in the final step) when the plain concrete of the panel is still wet and malleable. Then, plain concrete is chemically bonded to a lighter material than concrete. This step of the method is performed using a device, that precisely injects lighter material than concrete into the first spaces between the beams and at the same time levels the upper surface between the beams.
The injection (extrusion) device consists of a screw that presses the material lighter than concrete, a throat through which the material is laid out and a strip limiting the first filling space from the top, which forms and smoothes the material. The extrusion device is also known and used in the production of e.g. hollow floor slabs.
Thanks to the development of the method of producing concrete panels, a permanent connection of the surface of plain concrete space first with a material lighter than concrete is obtained. The panel is a complete, consistent product that is ready to use. Thanks to the application of the above described technology, part of the material lighter than concrete is an element of the panel and does not have to be introduced into the structure on the construction site in the form of separate lightweight blocks/hollow blocks.
The invention is shown in the drawing, in which:

Fig. 1a shows a perspective view of the concrete floor panel according to the invention.
Fig. 1b shows a perspective view of the concrete floor panel according to the invention with the exposed fragment of the first space.
Fig. 2 shows a perspective view of the concrete floor panels according to the invention stacked with the preferred separating and supporting reinforcement.
Fig. 3 shows a cross section through the floor according to the invention.

The following embodiments of the invention are intended to demonstrate selected, preferred variants of the invention. It is obvious to the person skilled in the art that within the scope of protection there are more implementations of the inventions than presented below.
A basic variant of the floor panel 1 according to the invention is shown in Figs. 1a and 1b.
The concrete floor panel 1 consists of a structure 2 made of plain concrete containing sunken prestressing elements 4 which are prestressing strings. The structure 2 consists of a slab 3 of plain concrete and two beams 5 of plain concrete placed on slab 2. Two strings run in slab 2 under each beam 5, one string runs through each beam 5. Beams 5 parallel to each other define on the slab 2 one first space 6, which is filled with polystyrene concrete, which is a part of the material 7 lighter than plain concrete. Polystyrene concrete is combined with plain concrete of the first space 6 with a permanent chemical bond formed during the extrusion process.
Ready-made panel 1 has a length of 8 m, width 60 cm, 20x20 distance between beams 5 (second space 10 x distance between beams 5).
It is possible to make panels 1 longer and the distance between beams 5 depends on the assumed width of slab 2. Depending on the application/customer's request, such panel 1 can be cut into panels from 1 m to 8 m long. The distance between beams 5 can also be up to e.g. 6x34 cm, where the first dimension is the external distance (second space 10) and the second dimension is the distance between beams 5.
Further preferred embodiments of the invention may have three, four, five and more beams 5.
In further embodiments of the invention, the material lighter than concrete is one of the materials listed in the claims. The material used does not require the use of other panel parameters.
Fig. 2 shows the concrete floor panels 1 according to the above example, stacked as prepared for pouring over concrete topping 9 to form floor 8. The second space 10 is shown, created by applying two panels 1. Fig. 2 also shows how the separating reinforcement 11 and the support reinforcement 12 can be arranged, however, as indicated above, such reinforcement is not required for the implementation of the invention and solving the technical problem by the invention.
Floor 8 according to the invention is explained in Fig. 3. Floor 8 with concrete panels 1, described in the example above, flooded with concrete topping 9 is presented in cross-section. According to the invention, concrete floor panels 1 are stacked and poured with concrete topping 9 so that, the concrete is introduced into the second spaces 10 created by applying panels 1. Concrete topping 9 also covers the part of material 7 which is polystyrene concrete.
The concrete floor panel as described in the embodiment above is made as follows.
In the first step, slab 3 was made of plain concrete with use of a "slipformer" type device. Subsequently, in the second step, two beams 5 on slab 3 were produced using the same technique. In the next step, liquid polystyrene concrete was injected between two beams 5 of plain concrete. Cycles follow one another, on a single machine, driving along the track (mould) at a speed of about 2m/min. The faster the polystyrene concrete is injected, the binding effect will be better. It is the best to do this directly after forming a slab 3 and beams 5. After the injection of polystyrene concrete, plain concrete and polystyrene concrete cures simultaneously. The resulting stresses between the concretes are much smaller than in other cases, when the times between the steps will be greater. The curing temperature should be 40-50°C. After about 20 hours, panel 1 is ready to be cut into sections according to the customer's request and is transported to the finished goods warehouse or directly to the construction site where it will be installed.
Thanks to the method according to the invention, a permanent connection between plain concrete and polystyrene concrete was obtained.
The second step of the method was performed using the injection (extrusion) device consists of a screw that presses the polystyrene concrete, a throat through which the polystyrene concrete is laid out and a strip limiting the first filling space 6 from the top, which forms and smoothes the material.

Reference numbers:

1 -: concrete floor panel
2 -: structure
3 -: slab
4 -: prestressing elements
5 -: beam
6 -: first space
7 -: part of the material lighter than plain concrete
8 -: floor
9 -: concrete topping
10 -: second space
11 -: separating reinforcement
12 -: support reinforcement

Claims

Concrete floor panel consisting of a structure made of plain concrete with reinforcement sunk inside and a part of lighter material than plain concrete, wherein the concrete structure consists of:
- plain concrete slab (3) where the reinforcement is in the form of prestressing elements (4), and

- at least two plain concrete beams (5) placed on the slab (3),
wherein the beams (5) define at least one first space (6) on the slab (3) where a part of the lighter material (7) than plain concrete is located, wherein the lighter material (7) than plain concrete is chosen from the group: polystyrene concrete, perlite concrete, expanded clay concrete, aerated concrete, foam concrete,
characterized in that the lighter material (7) than plain concrete is combined with a plain concrete within the range of the first space (6) with the permanent chemical bond.
Concrete floor panel according to claim 1, characterized in that the prestressing elements (4) are lines or prestressing wires.
Concrete floor panel according to claim 1, characterized in that two concrete beams (5) are placed on the slab (3).
Concrete floor panel according to claim 1, characterized in that the concrete beams (5) are placed on the slab (3) symmetrically and parallel to each other and to the panel (1) edges.
Concrete floor panel according to claim 1, characterized in that the material lighter than plain concrete is polystyrene concrete made of regranulate constituting shot-blasted recycled polystyrene.
Method of production the concrete floor panel as defined in Claim 1, comprising the steps of:
a. making a structure (2) of plain concrete containing sunk inside reinforcement using a slip method with a slipformer type device, where a slab (3) made of plain concrete in the compressed concrete technology is produced in the first place, where prestressing elements (4) are used as reinforcement, on which at least two beams (5) of plain concrete are formed,

b. injection into at least one of the first space (6) designated on the slab (3) by at least two beams (5) of lighter material (7) than plain concrete, chosen from the group: polystyrene concrete, perlite concrete, expanded clay concrete, aerated concrete, foam concrete,
wherein step b. is performed before the structure (2) performed in step a. becomes fixed, so when the plain concrete is still wet and malleable.
Floor comprising the stacked concrete floor panels (1) as defined in claim 1 poured with concrete topping.