[0001] 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.
[0002] 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.
[0003] 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.
[0004] 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.
[0005] 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.
[0006] Generally, two building material for floors are known and used in residential and
industrial construction industry.
[0007] Beam and block floors are the most common solution.
[0008] 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.
[0009] 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.
[0010] 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.
[0011] These disadvantages seemed to be eliminated by a solution based on the use of filigree
slabs.
[0012] 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.
[0013] 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.
[0014] 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.
[0015] The solution according to the invention combines features of known solutions, making
appropriate innovative improvements.
[0016] 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.
[0017] 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.
[0018] 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.
[0019] 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.
[0020] 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.
[0021] 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.
[0022] 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.
[0023] The length of the concrete flange can be arbitrary.
[0024] 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.
[0025] The concrete flange of the slab can be made e.g. of materials such as concrete, polymer
concrete, lightweight concrete or composite slab.
[0026] 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.
[0027] 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.
[0028] 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.
[0029] 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.
[0030] 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.
[0031] 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.
[0032] 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.
[0033] Preferably, the slab according to the invention comprises an additional reinforcement,
which is constituted by a longitudinal reinforcement.
[0034] Preferably, the longitudinal reinforcement is in the form of steel and/or composite
rods made of fibre glass or another polymer.
[0035] Preferably, the longitudinal reinforcement is constituted by wires and/or prestressing
steel cables.
[0036] 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.
[0037] Preferably, the concrete flange of the slab has a variable height in the transverse
cross-section.
[0038] 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.
[0039] Preferably, the flange of the slab is made of concrete, polymer concrete, lightweight
concrete or composite slabs.
[0040] 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.
[0041] 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.
[0042] 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.
1. 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.
2. A slab according to claim 1 characterised in that the additional reinforcement (3) is constituted by a longitudinal reinforcement (3a).
3. 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.
4. A slab according to claim 2 or 3 characterised in that the longitudinal reinforcement (3a) is constituted by wires and/or prestressing steel
cables.
5. 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.
6. A slab according to claim 1 characterised in that the flange of the slab has a variable height in the transverse cross-section.
7. 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.
8. 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.
9. A floor system characterised in that it comprises at least one slab with the features specified in claim 1.