EP3235967A1

EP3235967A1 - Reinforced concrete slab, especially a floor slab and a floor system

Info

Publication number: EP3235967A1
Application number: EP16184512.8A
Authority: EP
Inventors: Magdalena Lis
Original assignee: Individual
Current assignee: Individual
Priority date: 2016-04-22
Filing date: 2016-08-17
Publication date: 2017-10-25
Also published as: UA144242U; PL416945A1

Abstract

The object of the invention is a reinforced concrete slab, in particular a floor slab, characterised in that it is a prefabricate unit and that it has a supporting reinforcement in the form of at least one longitudinally arranged steel truss, and an additional reinforcement, wherein the height of the concrete flange of the slab is between 15 and 80 mm, and the width of the concrete flange of the slab is between 15 and 80 cm. The invention also comprises a floor system.

Description

The invention relates to a reinforced concrete slab, especially a floor slab and a floor system. The solution according to the invention is widely applicable in the construction industry.
The Polish patent number P. 173278 discloses a solution of a composite beam and block floor constituted by a thin large-size prefabricated reinforced concrete slab provided with a reinforcement protruding above its upper surface in the form of spatial trusses, running parallel to the span of the floor, and by inverted prefabricated reinforced concrete hollow core roof slabs arranged between these trusses, provided with outwardly protruding transverse and longitudinal reinforcement. The spaces between the hollow core roof slabs are filled with concrete, wherein the concrete in the spaces extending along the floor constitutes, together with the upper part of the hollow core roof slabs, supporting ribs of the structure. The whole structure is reinforced with a support reinforcement arranged in the supporting ribs of the structure.
The Polish patent number P. 166681 discloses a solution of a thin-walled reinforced concrete prefabricated floor slab, designed particularly for floors bending in two directions consisting of a reinforced concrete slab and protruding stiffeners in the shape of trusses with a triangular cross-section, whose lower zones are embedded in concrete and by upwardly protruding steel reinforcement loops arranged along the longitudinal edge of the concrete slab.
The Polish patent number P. 217612 discloses a solution of a prefabricated reinforced concrete slab equipped with grating supports and v-diverging slots along the lateral edges of the slab, additionally reinforced with concentrated connecting rods, which, after being filled with concrete topping, form a dowel connector.
The Polish patent number P. 402760 discloses, in turn, a solution of a steel and concrete beam to reinforce construction prefabricated units with a preferred ratio of weight per unit of their length. The beam according to this solution comprises a multi-rod openwork spatial reinforcement in the form of a truss located inside a concrete block shaped in the form of a solid, where the spatial steel reinforcement truss is equipped, in the upper part, with a special concrete form shaped in such a way that between the lower and the upper surface of the prefabricated floor, a free space is created.
Generally, two building material for floors are known and used in residential and industrial construction industry.
Beam and block floors are the most common solution.
Beam and block floors are formed by a combination of reinforced concrete floor beams and hollow blocks filling the spaces between the beams. Generally, spacing of the beams does not exceed 90 cm, and most often it is between 40 and 60 cm. Between the beams, fillings are arranged, which may be constituted by hollow blocks of ceramics, gravel and concrete, slag and concrete, crushed-brick concrete, lightweight concrete, foam polystyrene, plaster, etc. The upper part of the beam and block floor is a concrete slab made on site - topping concrete. It protects the hollow blocks against damage and is an underlay for the floor. The slab has a thickness of 3-7 cm. The total thickness of the floor is approx. 23-35 cm and depends on the thickness of the slab and on the height of the hollow blocks.
Elements of the floor of this type are relatively light (a prefabricated beam with a length of 6m weighs approx. 80-90 kg, a hollow block - 11-18 kg), thanks to which there is no need to use special equipment. However, in case of floors having ribs made on site, formwork is necessary.
The greatest disadvantage of the solution of this type is time and labour consumption resulting from the number of elements used in this floor. For example, per 100 m2 of a beam and block floor, approx. 700 elements, hollow blocks with dimensions of 25x50 cm and average weight of 15 kg, need to be arranged (which totals approx. 10t of manually arranged hollow blocks, in addition, it is necessary to previously arrange beams). Furthermore, the number of elements requiring to be arranged on the construction site makes the very process of installing this type of solution very dangerous. Workers working at the construction of a floor must take special care, they can move only through narrow beams supported on the walls of the building and watch out for the spaces between them. An additional disadvantage of this type of building material is its low sound insulation, which tends to be particularly bothersome to the users of the building.
These disadvantages seemed to be eliminated by a solution based on the use of filigree slabs.
Filigree is a stay-in-place formwork slab comprising longitudinal and transverse supporting reinforcement and embedded trusses allowing transport of slabs. Filigree slabs are always individually designed to measure of the building, their production and assembly requires close cooperation with the designer. In case of potential defects of the resulting slab, or of a misestimation of its dimensions, it is necessary to produce it again. The solution of this type of a slab cannot be cropped or otherwise adapted to the building on the construction site. During the installation of slabs on the construction site, reinforcement of floor tie beam is performed and an additional reinforcement of floor in the form of basic reinforcement of the structure or additional reinforcements in connection places of slabs is arranged. Then, a layer of concrete topping is poured, and the arranged slabs function as a formwork.
Construction of the floor when using this type of slabs is not particularly labour-intensive, but the size of the slabs is a significant disadvantage. The size of this type of slabs is generally significant, which in turn requires the use of heavy equipment both in the factory and on site. This feature also makes the transport of slabs very expensive, and their installation on the construction site requires the use of heavy equipment. Furthermore, slabs of this type are made to measure, and their production is preceded by the necessity to perform a number of structural calculations and to design an appropriate slab. Consequently, the use of this solution requires constant participation of the constructor in the process of both design and production, and installation of the slab. Neither can these slabs be cropped or otherwise adapted to measure the building on the construction site. Neither are these slabs ever prefabricated or available "on the spot" in stock. The waiting time for installation of a floor of filigree slabs is significant.
The primary objective of the invention described in this document was to eliminate the disadvantages of known solutions indicated above. The invention makes it possible to quickly obtain a durable floor without having to incur high time investment, as in the case of beam and block floors, or financial investment, as required by the transport and installation of filigree slabs. Furthermore, in the floor made of slabs according to the invention, improved parameters of bearing capacity and sound insulation compared to beam and hollow block floors are obtained. An additional advantageous feature is the ease and quickness of assembly, which significantly contributes to reducing the costs of making a floor.
The solution according to the invention combines features of known solutions, making appropriate innovative improvements.
A significant feature of the claimed solution is the possibility of prefabrication of finished elements for stock, thanks to which orders for delivery of slabs according to the invention can be carried out immediately, with no need to wait for the production of elements.
The reinforced slab according to the invention consists of a concrete flange and of a steel truss protruding above the surface thereof, whose lower zones are embedded in concrete.
The concrete slab according to the invention has been equipped with a suitable reinforcement, combining the features of the reinforcement characteristic of beam and block floors with a reinforcement typical of filigree slabs.
Thus, the slab according to the invention in the basic version has a supporting reinforcement and an additional reinforcement. The supporting reinforcement is constituted by at least one steel truss embedded in the slab. The truss is arranged longitudinally to the plane of the slab and centrally to its width. Elements of this reinforcement, usually in the form of cross-braces, protrude above the top surface of the slab and extend in parallel to the span of the floor. These elements facilitate installation of slabs on the construction site and facilitate the handling of slabs, and when poured over with a layer of concrete topping, reinforce its connection to the slab. The lower zones of the truss are embedded in concrete.
Furthermore, the slab can be equipped with additional reinforcement. The additional reinforcement can be present in the form of steel or composite rods or wires or prestressing steel cables longitudinally arranged in the slab. Alternatively, the slab can be equipped with a reinforcement of mesh made of steel or of artificial fibres. Both types of the additional reinforcement may also simultaneously be present in the slab.
The essence of the slab according to the invention is also its dimensions. Generally, it is desirable that the height of the flange of the concrete slab was between 15 and 80 mm, and the width of the flange of the concrete slab ranged between 15 and 80 cm. A slab ranging between these dimensions best performs its functions, also from the perspective of the assembly and transportation of finished slabs.
It should be noted that embedding in the central part of the slab a supporting reinforcement in the form of a steel truss requires thickening this part of the plate, while in the remaining part the thickness of the slab can be significantly smaller, which will favourably contribute to reducing the weight of the prefabricated unit. Therefore, the concrete flange of the slab may have a variable height, if this parameter will be measured after embedding the supporting reinforcement in the surface of the slab.
The length of the concrete flange can be arbitrary.
A significant feature of the slab according to the invention is also that elements of foam polystyrene, flexible foam polystyrene or other lightweight sound-insulating and/or heat-insulating material can be arranged on the flange of the concrete slab. This feature allows for reducing the weight of the floor and improving its heat- and sound-insulating parameters.
The concrete flange of the slab can be made e.g. of materials such as concrete, polymer concrete, lightweight concrete or composite slab.
The essence of the slab according to the invention is also the possibility to suitably modify it on the construction site. Thus, the solution according to the invention can also be e.g. arbitrarily cropped or punched on site, depending on demand. This allows for adapting the elements to the individual conditions of the building or to the requirements of the investor.
Thanks to using the solution according to the invention we obtain a durable floor which meets all the standards set for the floors used so far. An individual element obtained according to the invention is very thin, which allows for easy transport, handling and arranging of these elements in the floor on the walls of the building.
Furthermore, construction of a floor with the elements according to the invention is quicker and cheaper than construction of a floor with traditionally available solutions. Floor of this type does not require individual designing for each room in which it is to be used. Neither does the solution according to the invention require using of heavy equipment when producing and installing particular elements of the floor. The number of elements used in the construction of this type of floor was significantly reduced, which significantly reduced the time of installation of the floor. Concrete slabs according to the invention are lightweight, modular and prefabricated, and simultaneously have the highest strength and sound insulation parameters.
The concrete slab according to the invention can also be used in the construction of other surfaces than the floor, e.g. retaining walls, foundations, etc. The characteristics obtained in the slab according to the invention, such as its modularity, strength and relatively low weight provide broad opportunities for it to be used in construction industry. Reinforcing the slab with a supporting and additional reinforcement contributes to the improvement of its bearing capacity, which in turn significantly improves the properties of the slab used e.g. in the construction of retaining walls. It is because the retaining wall transfers the pressure of the secured construction facility onto the substrate, so that the parameters of its bearing capacity are extremely important. Thanks to the solutions used, the slabs can form a retaining wall with exceptional strength and resistance to high static loads and environmental conditions. The wall made of concrete slabs according to the invention is also simple, faster and cheaper to install than the traditional wall. Prefabricated units are set up quickly and easily, regardless of the weather.
Arranging the above described concrete slabs tightly in the floor on the walls of the building, and then pouring over them a layer of concrete topping, or reinforcing with an additional truss and pouring over a layer of concrete topping allows for obtaining an extremely durable and strong floor.
Primary advantages of the invention are:

standardisation and modularity of prefabricated units, which significantly improves the design work and allows manufacture for stock. The obtained panels are universal and can be used in many different buildings, which cannot be performed in the case of filigree floor, where the slabs are produced based on individual projects.
substantial reduction of the costs of installation compared to the beam and block floors (hollow blocks have been eliminated).
reduction in the number of construction elements necessary to complete the composite floor, with 700 in the case of beam and block floor, up to 30 in the case of modular concrete panels;
approx. 6-fold increase in production capacity as calculated per one worker in the production of modular concrete panels in relation to the production of filigree elements of the floor;
longitudinal, transverse cutting, side notches and drilling of holes are possible to perform on site, which significantly simplifies installation work. This work is performed without the necessity to change the design of the slab, and in the case of filigree floors, this is not possible. As a result, this significantly reduces the cost of producing the floor;
increase in transport efficiency by increasing the quantity of m² carried in one transport of floor, with 150m² in the case of beam and block floor, up to 200m² in the case of concrete slabs;
increase in safety during the process of construction of the floor and facilitating to workers to move at a construction site before integrating the floor with the concrete topping, due to the stability of supported slabs, in contrast to hollow blocks or bricks, which are present in the beam and block floor;
acceleration of the process of construction of the floor and the possibility to arrange two slabs at the same time, with simultaneous reduction in the quantity of necessary supports, which support unintegrated elements of the floor.

The essence of the solution according to the invention is a reinforced concrete slab, in particular a floor slab, characterised in that it is a prefabricate unit and it has a supporting reinforcement in the form of at least one longitudinally arranged steel truss, and an additional reinforcement, wherein the height of the concrete flange of the slab is between 15 and 80 mm, and the width of the concrete flange of the slab is between 15 and 80 cm.
Preferably, the slab according to the invention comprises an additional reinforcement, which is constituted by a longitudinal reinforcement.
Preferably, the longitudinal reinforcement is in the form of steel and/or composite rods made of fibre glass or another polymer.
Preferably, the longitudinal reinforcement is constituted by wires and/or prestressing steel cables.
Preferably, the additional reinforcement is constituted by a mesh made of steel and/or of artificial and/or composite fibres embedded in the plane of the slab.
Preferably, the concrete flange of the slab has a variable height in the transverse cross-section.
Preferably, elements of foam polystyrene, flexible foam polystyrene or other lightweight sound-insulating and/or heat-insulating material are arranged on the flange of the slab.
Preferably, the flange of the slab is made of concrete, polymer concrete, lightweight concrete or composite slabs.
The essence of the solution according to the invention is also a floor system, characterised in that it comprises at least one reinforced concrete slab which is prefabricate unit and which has a supporting reinforcement in the form of at least one longitudinally arranged steel truss, and an additional reinforcement, wherein the height of the concrete flange of the slab is between 15 and 80 mm, and the width of the concrete flange of the slab is between 15 and 80 cm.
The object according to the invention has been illustrated in the embodiment in the drawing, in which fig. 1 represents a reinforced concrete slab, and fig. 2 represents a concrete slab equipped with a steel truss with a supporting reinforcement, fig. 3 represents a concrete slab equipped with an additional longitudinal reinforcement, fig. 4 represents a concrete slab equipped with an additional reinforcement in the form of a mesh made of steel or of artificial fibres, fig. 5 represents a concrete slab equipped with an additional longitudinal reinforcement and in the form of a mesh made of steel or of artificial fibres, fig. 6 represents elements of foam polystyrene or other lightweight material.
A reinforced concrete slab 1, in particular a floor slab, comprises a supporting reinforcement 2 in the form of axially symmetrically arranged steel truss and an additional reinforcement 3 in the form of three longitudinally arranged steel rods 3a.
In another embodiment, the slab may comprise an additional reinforcement 3 in the form of a mesh 3b made of steel or artificial fibres.
An alternative option is if the additional reinforcement 3 is made in the form of longitudinal rods 3a and a mesh 3b, which may be a mesh made of steel, of polymers or of other artificial fibres. In an alternative embodiment, it is possible to arrange on the flange of the concrete slab, embedding therein or gluing to its surface sound- and heat-insulating elements 4 made of foam polystyrene or of another lightweight heat- or sound-insulating material.
Reinforced concrete slabs 1 are arranged tightly one next to another on the walls of the building and are then poured over with a layer of concrete topping. In an alternative embodiment of the floor system, before pouring a layer of concrete topping, an additional steel truss is arranged on the slabs and then the concrete topping is poured.

Claims

A reinforced concrete slab, in particular a floor slab, characterised in that it is a prefabricate unit and that it has a supporting reinforcement (2) in the form of at least one longitudinally arranged steel truss, and an additional reinforcement (3), wherein the height of the concrete flange of the slab (1) is between 15 and 80 mm, and the width of the concrete flange of the slab (1) is between 15 and 80 cm.
A slab according to claim 1 characterised in that the additional reinforcement (3) is constituted by a longitudinal reinforcement (3a).
A slab according to claim 1 characterised in that the longitudinal reinforcement (3a) is in the form of steel and/or composite rods made of fibre glass or another polymer.
A slab according to claim 2 or 3 characterised in that the longitudinal reinforcement (3a) is constituted by wires and/or prestressing steel cables.
A slab according to claim 1 or 2 characterised in that the additional reinforcement (3) is constituted by a mesh (3b) made of steel and/or of artificial and/or composite fibres embedded in the plane of the slab.
A slab according to claim 1 characterised in that the flange of the slab has a variable height in the transverse cross-section.
A slab according to claim 1 characterised in that on the flange of the slab are arranged elements (4) made of foam polystyrene, flexible foam polystyrene or other lightweight sound-insulating and/or heat-insulating material.
A slab according to claim 1 characterised in that the flange of the slab is made of concrete, polymer concrete, lightweight concrete or composite slabs.
A floor system characterised in that it comprises at least one slab with the features specified in claim 1.