US20060075701A1

US20060075701A1 - Composite construction element, in particular for manufacturing floor structures and wall structures for buildings and method for manufacturing the same

Info

Publication number: US20060075701A1
Application number: US11/139,576
Authority: US
Inventors: Piero Cretti
Original assignee: Plastedil SA
Current assignee: Plastedil SA
Priority date: 2004-10-13
Filing date: 2005-05-31
Publication date: 2006-04-13

Abstract

A composite construction element (1) is described, comprising:

a) at least one elongated body (2) made of expanded plastic material provided with opposite faces (2 a, 2 b);

b) at least one reinforcing section bar (7, 8) longitudinally extending in the elongated body (2) and having a first lateral portion (7 b, 8 b) protruding from a first face (2 a) of the elongated body (2);

wherein the first lateral portion (7 b, 8 b) of the reinforcing section bar (7, 8) is provided with a face (9, 10) extending substantially parallel to the first face (2 a) of the elongated body (2) made of expanded plastic material at predetermined distance therefrom.

Advantageously, the construction element (1) exhibits improved self-supporting characteristics and improved supporting characteristics of covering elements externally associated to the construction element itself.

Description

BACKGROUND OF THE INVENTION

In one general aspect thereof, the present invention relates to a composite construction element, which has a preferred but non-exclusive use in the manufacture of floor structures or vertical or horizontal wall structures for living units, warehouses, and buildings in general, as well as in the manufacture of external or partition walls of bodies for trucks or similar containment structures.
In the following description and in the appended claims, the expression: composite construction element, is used to indicate an element comprising an elongated body made of expanded plastic material, for example expanded polystyrene, and at least one reinforcing section bar at least partially incorporated in the elongated body itself.
In the following description and in the appended claims, the expression: floor, is used to indicate both a horizontal structure adapted to support the floor of each storey of a building (including the floor directly above the ground), and a horizontal or slanting covering structure adapted to close at the top the last storey of the building itself.

PRIOR ART

In the manufacture of construction elements for manufacturing walls, floor structures or containment structures in general, and in particular in the building field, it has long become widespread the use of construction elements made of expanded plastic material, preferably expanded polystyrene, in the form of slabs or section bars of suitable shape and size and having the function of heat and sound insulating material.
Within the framework of several applications in the building industry and in order to impart suitable self-supporting characteristics to such construction elements, the use has become widespread of incorporating one or more suitably shaped reinforcing section bars in the mass of expanded plastic material.
In the following description and in the appended claims, the term: “self-support”, is used to indicate the ability of the construction element to withstand without structural yielding all the stresses applied thereon during its transportation and/or installation.
Thus, for example, European Patent EP 0 459 924 discloses a self-supporting construction element of made of expanded plastic material, in particular a floor element, comprising a central body, substantially parallelepipedic, inside which a reinforcing section bar constituted by an I-shaped thin sheet is integrated during the forming operations.
While the construction elements of the type indicated above exhibit characteristics of light weight, comparative ease of installation and low cost, the Applicant has found that the mechanical characteristics that they possess are not always adequate for the various requirements which occur in practice.
The construction elements of known type, in fact, are not capable of providing mechanical characteristics other than a simple “self-support” despite the presence of one or more reinforcing section bars, generally made of a metal material, incorporated in the expanded plastic material.

SUMMARY OF THE INVENTION

The object of the present invention therefore is that of providing a composite construction element which is provided on the one side with improved self-supporting characteristics, that is an improved ability to withstand the stresses applied thereon during its installation, and on the other side, provided with improved supporting characteristics of covering elements externally associated to the construction element itself.
According to a first aspect thereof, the invention therefore relates to a composite construction element comprising:
a) at least one elongated body made of expanded plastic material provided with opposite faces;
b) at least one reinforcing section bar longitudinally extending in said at least one elongated body and having a first lateral portion protruding from a first face of said opposite faces of the elongated body.
wherein said first lateral portion is provided with a face extending substantially parallel to said first face of said at least one elongated body made of expanded plastic material at a predetermined distance therefrom.
In particular, the Applicant has perceived that the desired improved characteristics of load-bearing and of mechanical resistance of a composite construction element of the type indicated above can be achieved by partially incorporating in the elongated body made of expanded plastic material the reinforcing section bar(s) longitudinally extending in the latter, so as to have a first lateral portion protruding from one of the opposite faces of the elongated body.
In this way, the reinforcing section bar(s) advantageously carry(ies) out—thanks to the protruding lateral portion thereof—the function of providing a face on which it is possible to apply mechanical stresses greater than those which can be withstood by the elongated body made of expanded plastic material.
The composite construction elements of the invention therefore are capable of autonomously withstanding any static loads applied on the protruding lateral portion of the reinforcing section bars.
At the same time, the expanded plastic material of the elongated body carries out the advantageous function of stiffening and of firmly holding in position the reinforcing section bar(s), preventing any deformation of the same as a consequence of the stresses imparted thereon.
The Applicant has further perceived that it is possible to achieve at the same time an improved supporting action of covering elements external to the composite construction element by providing in the protruding lateral portion of the reinforcing section bar(s) the aforementioned face, preferably substantially planar, extending substantially parallel to at least one face of the elongated body made of expanded plastic material at a predetermined distance therefrom.
In this way, the construction element of the invention is advantageously provided with an element having a mechanical resistance (the face of the reinforcing section bar(s)) extending at a predetermined distance from the elongated body made of expanded plastic material and capable of supporting a variety of external covering elements, such as for example reinforcement metal structures, rigid panels having ornamental or structural function or one or more layers of covering material by means of an interposed supporting lath.
In a particularly preferred embodiment, the first lateral portion of the reinforcing section bar(s) protruding from the first face of the elongated body made of expanded plastic material is provided with a substantially planar face, so as to obtain a more effective supporting action of the loads applied thereon, and to have a suitably wide surface for fastening an external covering element.
In a preferred embodiment, the aforementioned at least one reinforcing section bar of the construction element is provided with a second lateral portion provided with a face extending substantially parallel to the second face of said opposite faces of the elongated body made of expanded plastic material.
Preferably, this second lateral portion of the reinforcing section bar(s) can be either entirely incorporated in the expanded plastic material, or it can protrude therefrom so that the aforementioned face is extending substantially parallel to the second face of the elongated body made of expanded plastic material at a predetermined distance therefrom.
In this way, the construction element is advantageously capable of withstanding a second external covering element—identical or different from that used for the first face of the elongated body made of expanded plastic material—at or at a predetermined distance from, the second face of said elongated body so as to easily meet the most varied requirements of surface finishing.
Also in this case, the second lateral portion of the reinforcing section bar(s) protruding from the second face of the elongated body made of expanded plastic material is provided with a preferably substantially planar face, so as to obtain a more effective supporting action of the loads applied thereon, and to have a suitably wide surface for fastening an external covering element.
Depending upon the selected covering element, having or not structural features, the construction elements of the invention may also achieve further improved load bearing characteristics.
Preferably, the reinforcing section bar is constituted by any material having suitable structural characteristics and compatible with the expanded plastic material, for example cold-rolled and preferably galvanized steel, rigid plastic materials such as PVC, polyester polymers, polycarbonate, acrylonitrile-butadiene-styrene (ABS) copolymers and the like.
According to a preferred embodiment of the invention, the reinforcing section bar is transversely extending in the central body of the construction element along substantially the entire thickness thereof.
Preferably, the reinforcing section bar is further longitudinally extending in the central body of the construction element along substantially the entire length thereof.
For obvious reasons of construction simplicity and in order to limit the production costs, the reinforcing section bar is preferably shaped as an L, a C, a Z or an I, for example by placing two C-shaped elements side by side matching the respective central portions.
Additional preferred features of the composite construction element of the invention are indicated in the dependent claims 4-31, the content of which is herein integrally incorporated by reference.
According to a second aspect thereof, the invention relates to a method for manufacturing a composite construction element of the type indicated above as defined in the attached claim 32.
Advantageously, such a method can be carried out with shearing, profiling and molding equipment conventional per se and known in the art.
Additional preferred features of the method of the invention are indicated in the dependent claims 33-40, the content of which is herein integrally incorporated by reference.
According to a third aspect thereof, the invention also relates to a floor structure for buildings comprising at last one composite construction element of the type illustrated in the present description and, more preferably, comprising a plurality of said construction elements arranged side by side.
According to a fourth aspect thereof, the invention also relates to a wall structure for buildings comprising at least one composite construction element of the type illustrated in the present description and, more preferably, comprising a plurality of said construction elements arranged side by side.

BRIEF DESCRIPTION OF THE DRAWINGS

Additional features and advantages of the invention will become more readily apparent from the description of some preferred embodiments of a composite construction element, of a floor structure and of a wall structure according to the invention, made hereinafter by way of a non-limiting example with reference to the annexed drawings.
In the drawings:
FIG. 1 shows a perspective view of a first embodiment of a composite construction element according to the invention;
FIG. 2 shows a perspective view, in enlarged scale, of some details of a second embodiment of the composite construction element of the invention;
FIG. 3 shows a perspective view, in enlarged scale, of an alternative preferred embodiment of the reinforcing section bar extending in the composite construction element of the invention;
FIG. 4 shows a perspective view, in enlarged scale, of a further preferred embodiment of the reinforcing section bar extending in the composite construction element of the invention;
FIG. 5 shows a perspective view, in partial cross-section, of a portion of a floor structure obtainable by placing a plurality of composite construction elements of the invention side by side;
FIG. 6 shows a perspective view, in enlarged scale and in partial cross-section, of an alternative preferred embodiment of a floor structure obtainable by placing a plurality of composite construction elements of the invention side by side;
FIG. 7 shows a perspective view, in enlarged scale, of some details of the floor structure of FIG. 6;
FIGS. 8-10 show perspective views of some details of alternative preferred embodiments of the composite construction element of the invention;
FIG. 11 shows a perspective view, in enlarged scale, of an alternative preferred embodiment of the reinforcing section bar extending in the composite construction element of the invention;
FIGS. 12-13 show perspective views of a portion of a wall structure obtainable by placing a plurality of composite construction elements of the invention side by side.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

With reference to FIGS. 1-13, a composite construction element made of expanded plastic material, for example expanded polystyrene, according to a first preferred embodiment of the present invention, is generally indicated at 1.
The construction element 1 of the illustrated example, can be usefully employed for manufacturing load-bearing and partition walls or for manufacturing floor structures of a building.
Alternatively, the construction element 1 of the illustrated example can also be usefully employed for manufacturing bodies for trucks or similar structures.
The composite construction element 1 comprises an elongated body 2 made of expanded plastic material, preferably substantially parallelepipedic in shape, provided with opposite faces, both preferably substantially planar, respectively indicated at 2 a and 2 b.
While in the illustrated example the faces 2 a, 2 b are substantially planar, it should be understood that their shape is not critical for the purposes of the invention; such a shape, in fact, can assume any other geometrical configuration useful for the intended purpose.
Preferably, the elongated body 2 has the following dimensions, determined at the design stage: a thickness comprised between about 40 and about 120 mm and, more preferably, comprised between about 60 and about 80 mm, a width comprised between about 500 and about 1200 mm and, more preferably, comprised between about 600 and about 1000 mm and a length greater than about 500 mm, the maximum length being determined by the design specifications at values substantially selectable as desired.
By way of a non-limiting example, the length of the elongated body 2 can be equal to about 13000 mm.
Within the framework of the present description and in the following claims, except where otherwise indicated, all numbers expressing amounts, quantities, percentages, and so forth, are to be understood as being modified in all instances by the term “about”. Also, all ranges include any combination of the maximum and minimum points disclosed and include any intermediate ranges therein, which may or may not be specifically enumerated herein.
In a way known per se, the body 2 is also laterally provided with opposite sides 3, 4 respectively provided with a groove 5 and, respectively, with a rib 6, preferably having a mating shape, longitudinally extending along the entire length of the construction element 1.
In this way, a plurality of construction elements 1 arranged side by side can be firmly connected to one another by means of a substantially joint-wise coupling. The composite construction element 1 further comprises at least one reinforcing section bar, preferably at least two reinforcing section bars 7, 8, preferably substantially identical to each other, longitudinally extending in the elongated body 2 and parallel to one another.
In the preferred embodiment illustrated, the reinforcing section bars 7, 8 are longitudinally extending in the elongated body 2 of the composite construction element 1 along substantially the entire length thereof.
Preferably, the reinforcing section bars 7, 8 are longitudinally extending in the elongated body 2 made of expanded plastic material at opposite parts of the longitudinal center plane of said body along a direction substantially parallel to said center plane.
Still more preferably, the reinforcing section bars 7, 8 are symmetrically arranged in the elongated body 2 with respect to said longitudinal center plane thereof.
Thanks to this arrangement of the reinforcing section bars 7, 8, it is advantageously possible to achieve balanced and symmetrical reinforcement characteristics of the elongated body at opposite parts of the longitudinal center plane thereof.
Preferably, the reinforcing section bars 7, 8 are made of a material having suitable structural characteristics, such as for example cold-rolled and preferably galvanized steel, shaped in a suitable manner.
In a preferred embodiment, the reinforcing section bars 7, 8 are coated at least in part and, still more preferably, entirely coated with a fire resistant film, for example obtained from a paint selected from the group comprising intumescent paints and antifire paints.
The composite construction element 1 of the invention is in this case advantageously capable of achieving suitable characteristics of fire resistance in case of fire thanks to the presence of the aforementioned film.
By way of example, the reinforcing section bars 7, 8 can be obtained from a sheet having a width comprised between about 100 mm and about 300 mm and, still more preferably, comprised between about 120 mm and about 250 mm and a thickness preferably comprised between about 0.4 mm and about 1.2 mm and still more preferably, comprised between about 0.5 mm and about 0.8 mm.
The reinforcing section bars 7, 8 are provided with a central body 7 a, 8 a, with a first lateral portion 7 b, 8 b protruding from the face 2 a of the elongated body 2 made of expanded plastic material and with a second lateral portion 7 c, 8 c essentially incorporated in the elongated body 2.
The first lateral portions 7 b, 8 b of the reinforcing section bars 7, 8 are provided with respective faces 9, 10, preferably substantially planar, extending substantially parallel to the face 2 a of the elongated body 2 made of expanded plastic material at a predetermined distance therefrom.
Advantageously, the faces 9, 10 define a surface for supporting a finishing element, for example a rigid panel of plasterboard, wood, rigid plastic material or other suitable material indicated at 11 in FIG. 1, or for supporting a substantially reticular metal structure for reinforcing a concrete casting, as illustrated in more detail hereinafter.
The rigid panel 11 can be fastened to the faces 9, 10 in a way known per se, for example by means of screws known per se and not shown.
In a preferred embodiment, the rigid panel 11 can incorporate at least one suitable fire retardant material, preferably in powder, granules or fibers, adapted to impart an improved fire resistance to the panel itself and, consequently, to the composite construction element 1 which includes the same.
Preferably, such a fire retardant material is selected from mineral fibers, such as fiber glass, mineral wool, inert materials such as perlite, glass spheres, expanded clay granules or other materials suitable for the purpose and known to those skilled in the art.
In an alternative preferred embodiment, the rigid panel 11 can be coated at least in part with a fire resistant film, for example obtained from a paint selected from the group comprising intumescent paints and antifire paints.
Preferably, the distance between the upper faces 9, 10 of the first lateral portions 7 b, 8 b of the reinforcing section bars 7, 8 and the face 2 a of the elongated body 2 made of expanded plastic material is comprised between about 10 mm and about 60 mm and, still more preferably, is comprised between about 20 mm and about 40 mm.
The reinforcing section bars 7 and 8 therefore carry out the following advantageous functions:

- they impart adequate load-bearing characteristics to the composite construction element 1;
- they support a covering element of the elongated body 2 made of expanded plastic material at a predetermined distance from its face 2 a creating a gap that can be either left substantially empty or filled with a suitable filling material optionally incorporating at least one fire retardant material adapted to impart an improved fire resistance to said material. In the first case, the composite construction element 1 exhibits improved sound insulation characteristics (thanks to the presence of air in the gap) and advantageously allows to house hydraulic pipes or electrical raceways, whereas in the second case the composite construction element 1 can exhibit improved characteristics of heat insulation, of finishing, of mechanical resistance or of fire resistance depending upon the type of material arranged between the covering element and the face 2 a of the elongated body 2;
- they impart improved characteristics of fire resistance to the composite construction element 1 if they are partly or entirely coated with a fire resistant film, for example obtained from a paint selected from the group comprising intumescent paints and antifire paints.

Preferably, the first lateral portion 7 b, 8 b of the reinforcing section bars 7, 8 is substantially hook-shaped and has in this preferred embodiment a substantially C-shaped end portion.
In this case, the aforementioned end portion constitutes a substantially box-shaped structure the back of which defines the aforementioned upper faces 9, 10 intended in this case to support the rigid panel 11.
Preferably, the central portion 7 a, 8 a of the reinforcing section bars 7, 8 has a height comprised between about 60 mm and about 320 mm.
In the preferred embodiment illustrated in FIG. 1, the second lateral portion 7 c, 8 c of the reinforcing section bars 7, 8 is for example constituted by a fin projecting in a cantilevered fashion from the central portion 7 a, 8 a of the reinforcing section bars.
The fins 7 c, 8 c of the reinforcing section bars 7, 8 carry out the function of providing a suitable supporting surface which an additional suitable covering element of the face 2 b of the composite construction element 1 can be fastened to, such as for example a second rigid panel of plasterboard, wood, rigid plastic material, or other suitable material indicated at 12 in FIG. 1 or, alternatively, a stretched lath for supporting at least one covering layer (not shown in such figure).
The rigid panel 12 can be fastened to the fins 7 c, 8 c in a way known per se, for example by means of screws known per se and not shown.
In this case, the construction element 1 of the invention is capable of achieving advantageous load-bearing characteristics, i.e. it is capable of autonomously withstanding any static loads applied thereon.
Also in this case, it is possible to impart improved characteristics of fire resistance to the composite construction element 1 by using a rigid panel 12 incorporating at least one fire retardant material adapted to impart an improved fire resistance to the panel itself or by coating at least in part the rigid panel 12 with a fire resistant film for example obtained from a paint selected from the group comprising intumescent paints and antifire paints.
If the covering element of the face 2 b of the composite construction element 1 is constituted by a covering layer supported by a stretched lath, such advantageous characteristics can be achieved by incorporating in the material used for forming the layer (for example plaster or cement) at least one suitable fire retardant material, for example one of the materials indicated hereinbefore, adapted to impart improved fire resistance properties.
In the preferred embodiment illustrated in FIG. 1, the fins 7 c, 8 c of the reinforcing section bars 7, 8 are provided with an initial portion extending flush with and substantially parallel to the face 2 b of the elongated body 2 and with an end portion forming with respect to the aforementioned initial portion an angle comprised between 40° and 120° and, still more preferably, equal to about 90°.
Preferably, the initial portion of the fins 7 c, 8 c of the reinforcing section bars 7, 8 is provided with a face 13, 14 preferably substantially planar.
Preferably, furthermore, such initial portion of the fins 7 c, 8 c of the reinforcing section bars 7, 8 has a length comprised between about 15 mm and about 40 mm and, still more preferably, comprised between about 20 mm and about 30 mm.
Advantageously, such initial portion carries out the function of providing a suitable supporting surface which a covering element can be fastened to, for example the aforementioned rigid panel 12 or a lath for supporting at least one covering layer, for example of plaster, whereas the end portion increases the reinforcing action carried out by the reinforcing section bars 7, 8 under bending loads.
Tests carried out by the Applicant, furthermore, have shown that such a configuration of the fins 7 c, 8 c contributes to further stiffen the reinforcing section bars 7, 8, thus further increasing the self-supporting and compression resistance characteristics of the composite construction element 1.
In this preferred embodiment, the substantially planar faces 9, 10 of the first lateral portion 7 b, 8 b and the substantially planar faces 13, 14 of the fins (second lateral portions) 7 c, 8 c of the reinforcing section bars 7, 8 are both substantially perpendicular to the central portion 7 a, 8 a of the latter.
In this preferred embodiment, furthermore, the reinforcing section bars 7, 8 of the aforementioned pair are preferably spaced apart from one another by a predetermined distance, so as to suitably distribute the reinforcing section bars 7, 8 in the elongated body 2, achieving in this way some advantageous technical effects: possibility of homogeneously distributing the reinforcing action exerted by them; possibility of homogeneously distributing the loads applied to the reinforcing section bars 7, 8 and finally, possibility of arranging in a known and reproducible manner the fins 7 c, 8 c of the reinforcing section bars 7, 8 so as to know their position even when such fins are completely embedded in the mass of expanded plastic material and as such, are not visible from the outside.
In the preferred embodiment illustrated in FIG. 1, the reinforcing section bars 7, 8 are arranged in the elongated body 2 at a predetermined distance from one another; preferably, the distance d between the centre line of the fins 7 c, 8 c—measured along a direction substantially perpendicular to the longitudinal axis of the elongated body 2—is equal to about 300 mm.
From the preceding description, the features and the technical effects that can be achieved by the composite construction element 1 of the invention are immediately clear.
Firstly, the composite construction element 1 is provided with improved load-bearing characteristics thanks to the presence of the first protruding lateral portions 7 b, 8 b of the reinforcing section bars 7, 8, both provided with faces 9, 10 preferably substantially planar on which it is possible to apply mechanical stresses greater than those that can be withstood by the elongated body 2 made of expanded plastic material.
Secondly, the expanded plastic material of the elongated body 2 carries out the advantageous function of stiffening and firmly holding in position the reinforcing section bars 7, 8, preventing that the same could be deformed as a consequence of the stresses imparted thereon.
Thirdly, the composite construction element 1 allows to easily support external covering elements thanks both to the substantially planar faces 9, 10 extending substantially parallel to the face 2 a of the elongated body 2 made of expanded plastic material at a predetermined distance therefrom, and to the fins 7 c, 8 c extending flush with the face 2 b of the elongated body 2 made of expanded plastic material.
Fourthly, the composite construction element 1 allows to achieve improved characteristics of fire resistance thanks to the partial or total coating of the reinforcing section bars 7, 8 with a fire resistant film for example obtained from a paint selected from the group comprising intumescent paints and antifire paints and/or thanks to the use of a covering element incorporating at least one fire retardant material adapted to impart an improved fire resistance, or of a covering element at least partially coated with a fire resistant film.
FIGS. 2-13 schematically illustrate additional embodiments of the composite construction element 1 according to the present invention. These additional embodiments essentially achieve both the technical effects and the advantages of the preferred embodiment illustrated above and the further technical effects and advantages described hereinafter.
In the following description and in such figures, the components of the construction element 1 structurally or functionally equivalent to those illustrated with reference to the previous embodiment shall be indicated with the same reference numerals and will not be further described.
According to the embodiment illustrated in FIG. 2, the reinforcing section bars 7, 8 comprise respective second lateral portions 7 c, 8 c substantially fin-shaped and provided with a substantially planar face 13, 14.
The fins 7 c, 8 c are in this case entirely incorporated in the elongated body 2 made of expanded plastic material and are arranged at a predetermined distance from the face 2 b of such elongated body 2.
Preferably, the fins 7 c, 8 c are arranged at a distance d′ preferably comprised between about 5 mm and about 15 mm from the face 2 b of the elongated body 2.
In this way, it is possible to fasten suitable covering elements of the face 2 b of the elongated body 2 of the composite construction element 1—for example the aforementioned panel 12 made of plasterboard—to the fins 7 c, 8 c of the reinforcing section bars 7, 8 by using fastening elements (not shown) of limited length.
Since the fins 7 c, 8 c of the reinforcing section bars 7, 8 are not visible from the outside, in order to fasten the covering elements it is necessary in this case to know in advance the position of such fins inside the mass of expanded plastic material with respect to a reference element, such as for example with respect to the sides 3, 4 or with respect to the longitudinal center plane of the elongated body 2 made of expanded plastic material.
With reference to FIGS. 3 and 4, some additional preferred embodiments of the reinforcing section bars 7, 8 will now be illustrated.
According to the embodiment illustrated in FIG. 3, the reinforcing section bars 7, 8 of the composite construction elements 1 (of which only the reinforcing section bar 7 is shown in FIG. 3 for simplicity) are provided with respective first portions 7 b, 8 b substantially similar to those of the embodiment illustrated with reference to FIGS. 1 and 2.
In this case, the reinforcing section bars 7, 8 of the composite construction elements 1 are advantageously provided with a plurality of openings 15, preferably of circular shape, formed in the central portion 7 a, 8 a thereof comprised between the aforementioned first and second lateral portions 7 b, 8 b and 7 c, 8 c.
The openings 15 carry out the dual advantageous function of lightening the reinforcing section bars 7, 8 and of allowing an even more intimate integration thereof in the mass of expanded plastic material.
Thanks to the presence of the openings 15, in fact, the mass of expanded plastic material is capable of interpenetrating with the reinforcing section bars 7, 8 during the molding operation, integrating and firmly holding in place the reinforcing section bars 7, 8 within the elongated body 2 of the composite construction element 1.
This intimate integration of the reinforcing section bars 7, 8 in the mass of expanded plastic material, furthermore, prevents any deformation or bending along the transversal direction of the reinforcing section bars 7, 8 even though they are essentially constituted by a fairly thin metal sheet.
Preferably, the openings 15 have a total area comprised between about 5% and about 50% of the total area of each reinforcing section bar 7, 8, where the expression: total area of each reinforcing section bar, is used to indicate the area of the overall surface of the section bar including that of the opposite lateral portions 7 b, 7 c and 8 b, 8 c (that is, the area of the total lateral surface before forming such portions and the openings 15).
Still more preferably, the openings 15 formed in the central portion 7 a, 8 a of the reinforcing section bars 7, 8 have a total area comprised between about 20% and about 30% of the total area thereof.
The openings 15 have a diameter preferably comprised between about 15 mm and about 100 mm and, more preferably, comprised between about 40 mm and about 70 mm.
In a preferred embodiment, the openings 15 are pitchwise arranged in the central portion 7 a, 8 a of the reinforcing section bars 7, 8 along the center plane of the section bars themselves.
Preferably, the pitch of the openings 15 is comprised between about 50 and about 100 mm and, still more preferably, is equal to about 75 mm.
According to the embodiment illustrated in FIG. 4, the reinforcing section bars 7, 8 of the composite construction elements 1 (of which only the reinforcing section bar 7 is shown in FIG. 4 for simplicity) are provided with openings 15 entirely similar to those of the reinforcing section bars of FIG. 3 and with a first substantially hook-shaped lateral portion 7 b, 8 b having a shape substantially resembling an upturned U.
Thanks to this feature, the first lateral portion 7 b, 8 b of the reinforcing section bars 7, 8—preferably essentially constituted by a fairly thin sheet—substantially acts as a spring whenever it engages suitably grooved covering elements connectable in a snap-wise fashion in such first lateral portion 7 b, 8 b.
Preferably, such first lateral portion of the reinforcing section bars 7, 8 is provided in this case with lateral portions, indicated at 16 and 17, which are substantially tapered so as to increase the spring effect achieved by this substantially hook-wise configuration.
With reference to FIG. 5, a floor structure 18 that can be manufactured by means of a plurality of composite construction elements 1 according to the invention, for example each incorporating a pair of reinforcing section bars 7, 8 according to the embodiment of FIG. 4, will now be described.
According to this embodiment, the floor structure 18 is especially suitable for constructing the so-called “wide span” floors.
The floor structure 18 comprises a plurality of composite construction elements 1 arranged side by side, a plurality of floor elements 19 made of expanded plastic material supported by the composite construction elements 1 and a substantially reticular metal structure 20 for reinforcing a concrete casting, schematically indicated at 21 in FIG. 5, arranged between the floor elements 19.
In the following description and in the appended claims, the expression: substantially reticular metal structure, is used to indicate a reinforcement metal structure comprising a plurality of longitudinal reinforcing elements and a plurality of transversal reinforcing elements of the casting crossed with one another so as to form a grid extending substantially along the entire extension of the floor structure to be manufactured.
The latter is defined in the field as a floor structure provided with “crossed reinforcement rods” and allows to manufacture floors having a length greater than those that can be achieved by floor structures having the same thickness but riot provided with substantially reticular reinforcement metal structures.
Advantageously, the composite construction elements 1 are laying at the opposite ends thereof on respective supporting structures of a building (not shown), such as for example beams and/or load-bearing walls.
In this way, the composite construction elements 1 form in this case as many supporting elements adapted to define a base of the floor structure 18 adapted to support the floor elements 19 and the reinforcement metal structure 20 and adapted to receive the concrete casting 21.
In this embodiment, the reinforcing section bars 7, 8 of the composite construction elements 1 carry out the following advantageous functions:

- they impart suitable self-supporting characteristics to the composite construction elements 1;
- they support the floor elements 19 and firmly hold the same in place;
- they support the reinforcement metal structure 20 of the casting at a predetermined distance from the upper face 2 a of the elongated body 2 of the composite construction elements 1;
- they impart improved characteristics of fire resistance to the composite construction elements 1 whenever they are partially or entirely coated with a fire resistant film, for example obtained from a paint selected from the group comprising intumescent paints and antifire paints.

Since the reinforcement metal structure 20 of the casting is supported at a predetermined distance from the upper face 2 a of the elongated body 2 of the composite construction elements 1, it is advantageously ensured in a simple and effective manner that the concrete casting 21 can easily fill the spaces below the reinforcement metal structure 20 as required by the building regulations currently in force.
Advantageously, furthermore, the first lateral portions 7 b, 8 b of the reinforcing section bars 7, 8—preferably essentially constituted by a fairly thin metal sheet—substantially act as springs upon their engagement with the floor elements 19.
In the preferred embodiment of the floor structure 18 illustrated in FIG. 5, the reinforcement metal structure 20 can be advantageously firmly associated to the reinforcing section bars 7, 8 by means of a plurality of staples 38 having a central body 38 a substantially shaped as an upturned U and having opposite free ends 38 b, 38 c projecting in a cantilevered fashion from the central body 38 a and adapted to engage the lateral portions 7 b, 8 b of the reinforcing section bars 7, 8.
Preferably, the staples 38 are constituted by a wire of a suitable structural material, for example metal, so as to constitute substantially spring-wise connecting means thanks to the elasticity of the material.
Thanks to the ensuing stable association of the reinforcing section bars 7, 8 to the reinforcement metal structure 20, the composite construction element 1 advantageously allows to achieve improved characteristics of fire resistance, since the covering elements, in this case the rigid panels 12 associated to the face 2 b of the elongated body 2, are firmly held by the reinforcement metal structure 20 embedded in the concrete casting 21 by means of the reinforcing section bars 7, 8.
In case of fire, therefore, the rigid panels 12 do not detach from the composite construction element 1 even in the presence of a complete collapse of the elongated body 2 made of expanded plastic material.
Advantageously, furthermore, the characteristics of fire resistance of the floor structure 18 can be further improved if the rigid panels 12 incorporate at least one fire retardant material adapted to impart an improved fire resistance or are coated at least in part with a fire resistant film.
Preferably, the floor elements 19 made of expanded plastic material supported by the composite construction elements 1 are arranged at a predetermined distance from one another along the floor structure 18—both along a longitudinal and along a transversal direction—so as to define a plurality of transversal channels 22 and a plurality of longitudinal channels 23 adapted to house the concrete casting 21.
In this preferred embodiment, the floor elements 19 are arranged astride of the composite construction elements 1.
Thanks to this arrangement, it is advantageously possible to increase the characteristics of mechanical resistance of the floor structure 18 since the stresses imparted to the structure by the concrete casting 21 do not concern the projecting portions of the elongated bodies 2 made of expanded plastic material (the portion of plastic material extending between the reinforcing section bars 7, 8 and the sides 3, 4 of the elongated bodies 2).
In the illustrated example, each floor element 19 comprises a central body 19 a substantially parallelepipedic, in which a plurality of parallel cavities 24 is longitudinally defined.
Advantageously, the floor elements 19 made of expanded plastic material can be realized with any desired height, so as to regulate as desired the thickness of the floor structure 18 and, therefore, the maximum length of the final floor.
Preferably, the floor elements 19 have a thickness comprised between about 160 mm and about 500 mm and, still more preferably, comprised between about 180 mm and about 300 mm.
Preferably, the floor elements 19 have the following further dimensions, determined at the design stage: a width comprised between about 450 and about 500 mm and a length greater than about 300 mm, the maximum length being determined by the design specifications at values substantially selectable as desired.
By way of a non-limiting example, the length of the floor elements 19 can be comprised between 300 mm and 13000 mm.
Preferably, the floor elements 19 are arranged on the composite construction elements 1 so as to form a grid of transversal channels 22 and longitudinal-channels 23 substantially perpendicular to one another.
Advantageously, the width of the channels 22 and 23 can be determined by a man skilled in the art on the basis of the design specifications. By way of an example only, such a width may be comprised between about 100 and about 200 mm.
In this preferred embodiment of the floor structure 18, the composite construction elements 1 thus constitute as many joists on which the floor elements 19 rest to form a so-called “panelled” floor structure.
Within the framework of this preferred embodiment, the floor elements 19 are preferably provided at a lower side with at least one and preferably a pair of longitudinal grooves 25 adapted to house the first lateral portions 7 b, 8 b of the reinforcing section bars 7, 8, so as to have a firm connection between the floor elements 19 and the composite construction elements 1 of the floor structure 18.
Preferably, the longitudinal grooves 25 are configured so as to have a shape substantially mating the shape of the first lateral portions 7 b, 8 b of the reinforcing section bars 7, 8 projecting from the composite construction elements 1, so as to increase the stability of the connection between the reinforcing section bars 7, 8 and the floor elements 19.
Thus, for example, in the preferred embodiment illustrated in FIG. 5, the longitudinal grooves 25 are substantially dovetail-shaped with opposite lateral walls tapered in such a way as to firmly hold in the grooves 25, with a substantially snap-wise-connection, the first lateral portions 7 b, 8 b of the reinforcing section bars 7, 8, having in turn tapered lateral portions 16, 17 as better illustrated in FIG. 4.
According to the invention and as described above, the reinforcement metal structure 20 of the concrete casting 21 is supported by the first lateral portions 7 b, 8 b of the reinforcing section bars 7, 8 at a predetermined distance from the upper face 2 a of the elongated body 2 made of expanded plastic material.
Within the framework of this preferred embodiment, the reinforcement metal structure 20 of the casting comprises a plurality of transversal reinforcement elements of the casting 21, generally indicated at 26, and a plurality of longitudinal reinforcement elements of the casting, generally indicated at 27, respectively housed in the aforementioned transversal and longitudinal channels 22, 23.
In this way, it is advantageously possible to realize, within the framework of the aforementioned “panelled” floor structure, zones of reinforced concrete arranged only where needed on the basis of the design parameters, with a reduction of the weight and of the costs for manufacturing the final floor.
Preferably, the transversal reinforcement elements 26 of the casting lay on the first lateral portions 7 b, 8 b of the reinforcing section bars 7, 8 and in particular, lay on the substantially planar faces 9, 10 of such first lateral portions 7 b, 8 b and are firmly associated to the reinforcing section bars 7, 8 in way conventional per se, for example by means of the staples 38 described hereinbefore.
In this preferred embodiment, the longitudinal reinforcement elements 27 of the casting 21 lay on the transversal reinforcement elements 26 and are firmly associated to the same in way conventional per se, for example by means of strings 39 of conventional type and constituted by the conventional iron wires used to this end in the art.
Thanks to the aforementioned supporting configuration of the transversal and of the longitudinal reinforcement elements 26, 27 of the casting 21 provided by the composite construction elements 1 of the invention, it is advantageously possible to arrange the lower portion thereof—the portion which is subjected to the tensile stresses—near the lower portion of the floor structure 18 with an increase of the characteristics of resistance to external loads of the final floor.
For the purposes of the invention, the specific shape and structure of the transversal and of the longitudinal reinforcement elements 26, 27 of the reinforcement metal structure 20 is not critical, provided that they supply the necessary amount of metal according to the design specifications. Thus, for example, the transversal and the longitudinal reinforcement elements 26, 27 of the reinforcement metal structure 20 can be constituted by a plurality of iron rods suitably spaced from one another or they can be constituted by substantially trestle-shaped structures according to what is known to a man skilled in the art.
From the foregoing description, the features and the technical effects that can be achieved by the floor structure 18 of the invention are immediately clear.
Thanks to the structural characteristics of the composite construction elements 1 and, in particular, to their self-supporting characteristics and to their ability of supporting the reinforcement metal structure 20, it is possible in the first place to minimize the labor required to manufacture the final floor at the yard.
The operations required to manufacture the final floor, in fact, essentially comprise the steps of laying a plurality of composite construction elements 1 on the load-bearing structures of the building being erected, of arranging thereon the floor elements 19 and the reinforcement metal structure 20 and then, of casting the concrete on the floor structure 18 thus assembled.
Once the floor structure 18 has been assembled, the function of containing the concrete casting 21 is ensured by the transversal and by the longitudinal channels 22, 23 defined between the floor elements 19 and the composite construction elements 1.
Advantageously, the aforementioned operating steps can be carried out without using temporary supports for lengths of the floor structure 18 up to about 2 meters or using a limited number thereof for greater lengths.
Advantageously, furthermore, the aforementioned laying step of the composite construction elements 1 can be readily carried out with a minimum labor, thanks to the compactness, lightness and handiness of the elements themselves.
Finally, the floor structure 18 according to the invention achieves improved characteristics of fire resistance in case of fire thanks to one or more of the following features:

- to the fact that the covering elements associated to the face 2 b of the elongated body 2, in this case constituted by the rigid panels 12, are firmly held by the reinforcement metal structure 20 embedded in the concrete casting 21 by means of the reinforcing section bars 7, 8;
- to the fact that the reinforcing section bars 7, 8 can be coated at least in part with a fire resistant film;
- to the fact that the covering elements associated to the face 2 b of the elongated body 2 can incorporate at least one fire retardant material adapted to impart an improved fire resistance or to the fact that the covering elements can be coated at least in part with a fire resistant film.

According to an another preferred embodiment of the floor structure 18 illustrated in FIGS. 6 and 7, the elongated body 2 of the composite construction elements 1 is provided with a plurality of cavities 40 substantially parallel to one another and longitudinally extending in a central portion of the elongated body 2 between the reinforcing section bars 7, 8.
Advantageously, the cavities 40 contribute to lighten the elongated body 2 making the same easier to handle during the installation.
The elongated body 2 made of expanded plastic material is further provided with a plurality of longitudinal ribs 41, 42 made of expanded plastic material, substantially parallel to one another, projecting in a cantilevered fashion from the upper face 2 a of the elongated body 2 at opposite parts of the longitudinal center plane thereof.
In this preferred embodiment, the elongated body 2 made of expanded plastic material is also provided with a pair of projections 43, 44 laterally and longitudinally extending at opposite parts of the longitudinal ribs 41, 42 towards the opposite sides 3 and 4 of the elongated body 3 in which the groove 5 and, respectively, the rib 6 are formed.
Preferably, the longitudinal ribs 41, 42 integrally extend substantially perpendicularly to the upper face 2 a of the elongated body 3 and are preferably obtained at the molding stage of the elongated body 2.
In this preferred embodiment, the reinforcing section bars 7, 8 of the composite construction elements 1 are substantially Z-shaped and each of them comprises respective first lateral portions 7 b, 8 b substantially fin-shaped associated to the longitudinal ribs 41, 42 made of expanded plastic material projecting in a cantilevered fashion from the upper face 2 a of the elongated body 2.
In this preferred embodiment, the second lateral portions 7 c, 8 c of the reinforcing section bars 7, 8 are constituted by respective fins perpendicularly extending from the ends of the central portion 7 a, 8 a opposite to that of the fins 7 b, 8 b and at opposite side of the central portion 7 a, 8 a.
Preferably, furthermore, the upper face 9, 10 of the first fins 7 b, 8 b of the reinforcing section bars 7, 8 is extending at least in part substantially flush with an upper face 41 a, 42 a of the longitudinal ribs 41, 42 of the elongated body 2 made of expanded plastic material.
In this way, the assembly constituted by the longitudinal ribs 41, 42 and by the first fins 7 b, 8 b forms a rigid structure adapted to effectively support the reinforcement metal structure 20.
Similarly to what has been described hereinabove with reference to the previous embodiment of the floor structure 18, the floor elements 19 are provided with longitudinal grooves 25 having a shape substantially mating the shape of the longitudinal ribs 41, 42 incorporating the first fins 7 b, 8 b of the reinforcing section bars 7, 8 and are engageable with a substantially snap-wise connection on such ribs. In this preferred embodiment, the fins 7 b, 8 b and 7 c, 8 c comprise a first portion substantially rectilinear and substantially perpendicular to the central portion 7 a, 8 a of the reinforcing section bars 7, 8 and an second portion, or end portion, inclined and forming an angle of predetermined value with the first portion.
Preferably, the first portion of the fins 7 b, 8 b and 7 c, 8 c has a width equal to about 40 mm, whereas the end portion has a width equal to about 5 mm and forms with respect to the first portion an angle equal to about 90° in the case of the second fins 7 c, 8 c and equal to about 45° in the case of the first fins 7 b, 8 b.
In an additional embodiment, the end portion of the first fins 7 b, 8 b can be radiused to the first portion by means of a substantially curvilinear joining zone.
Preferably, the reinforcing section bars 7, 8 are arranged in a mirror fashion at opposite parts of the longitudinal center plane of the elongated body 2 so as to impart optimum characteristics of load resistance to the composite construction element 1 as a whole. Thanks to this arrangement, the reinforcing section bars 7, 8 are provided with second fins 7 c, 8 c extending at opposite parts of the longitudinal center plane of the elongated body 2 made of expanded plastic material so as to form a configuration that advantageously improves the characteristics of resistance to the bending loads of the composite construction element 1, in particular those to the loads applied to the projections 43, 44 of the elongated body 2 made of expanded plastic material arranged between the reinforcing section bars 7, 8 and the opposite sides 3, 4 of the aforementioned body.
In the preferred embodiment illustrated in FIGS. 6 and 7, the first fins 7 b, 8 b and the second fins 7 c, 8 c of the reinforcing section bars 7, 8 are provided with respective longitudinal ribs 45, 46 adapted to stiffen the structure thereof, and in the case of the second fins 7 c, 8 c, adapted to form a notch for the introduction of the tip of fastening means, for example screws, for anchoring a rigid covering element, for example the panel 12 made of plasterboard, to the reinforcing section bars 7, 8.
Similarly to the embodiments illustrated hereinabove, furthermore, the reinforcing section bars 7, 8 are provided with a plurality of openings 15, preferably of circular shape, formed in the central portion 7 a, 8 a comprised between the first fins 7 b, 8 b and the second fins 7 c, 8 c.
Also in this case, the openings 15 carry out the dual advantageous function of lightening the reinforcing section bars 7, 8 and of allowing a still more intimate integration thereof within the mass of expanded plastic material.
In this preferred embodiment, furthermore, the staples 38 engage at their ends 38 b, 38 c the lower portion of the longitudinal ribs 41, 42 which forms an undercut which is hooked by the aforementioned ends of the staples 38.
Unlike what is illustrated in FIG. 5, the floor elements 19 are arranged so that each longitudinal row of floor elements 19 is supported by one and the same composite construction element 1.
In this case, it is therefore advantageously possible to pre-assemble at the factory a plurality of floor elements 19 longitudinally aligned on one and the same composite construction element 1 with an additional simplification of the laying operations of the floor structure 18 carried out at the yard.
In an additional embodiment, not shown, the composite construction elements 1 of the invention can be provided with longitudinal ribs projecting in a cantilevered fashion from both faces 2 a, 2 b of the elongated body 2 made of expanded plastic material, in which case the second lateral portions 7 c, 8 c of the reinforcing section bars 7, 8 will assume a configuration similar to that of the first lateral portions 7 b, 8 b illustrated with reference to FIGS. 6 and 7.
According to the preferred embodiment illustrated in FIG. 8, the reinforcing section bars 7, 8 of the construction element 1 are substantially Z-shaped and each of them comprises a plurality of openings 15 pitchwise formed in the central portion 7 a, 8 a thereof as described hereinbefore.
In this preferred embodiment, the second lateral portion 7 c of the reinforcing section bar 7 protrudes from the face 2 b of the elongated body 2 made of expanded plastic material and is provided with a face 13, preferably substantially planar, extending substantially parallel to the face 2 b at a predetermined distance therefrom.
Preferably, the distance between the face 13 of the second lateral portion 7 c of the reinforcing section bar 7 and the face 2 b of the elongated body 2 made of expanded plastic material is comprised between about 10 mm and about 60 mm and, still more preferably, comprised between about 20 mm and about 40 mm.
The first lateral portion 7 b of the reinforcing section bar 7 is on the other hand substantially incorporated in the expanded plastic material, so that the face 9 is extending flush with the face 2 a of the elongated body 2 made of expanded plastic material.
Conversely, the first lateral portion 8 b of the reinforcing section bar 8 protrudes from the face 2 a of the elongated body 2 made of expanded plastic material and is provided with a face 10, preferably substantially planar, extending substantially parallel to the face 2 a at a predetermined distance therefrom, preferably at a distance similar to that indicated above for the face 13 of the lateral portion 7 c.
The second lateral portion 8 c of the reinforcing section bar 8 is on the other hand substantially incorporated in the expanded plastic material, so that the face 14 is extending flush with the face 2 b of the elongated body 2 made of expanded plastic material.
In this preferred embodiment, the first and the second lateral portions 7 b, 8 b and 7 c, 8 c of the reinforcing section bars 7, 8 are for example constituted by respective fins extending perpendicularly from the ends of the central portion 7 a, 8 a of the section bars 7, 8 at opposite sides thereof.
Similarly to the embodiments illustrated hereinabove, the fins 7 b, 8 b and 7 c, 8 c comprise also in this case a first portion rectilinear and substantially perpendicular to the central portion 7 a and 8 a of the reinforcing section bars 7, 8 and a second end portion inclined and forming an angle of predetermined value with the first portion. Preferably, such an angle is equal to about 90°.
This additional embodiment of the composite construction elements 1 advantageously allows both to have improved characteristics of resistance to the bending loads and to support external covering elements (for example rigid panels made of plasterboard and/or laths supporting plaster layers, not shown) at opposite parts of the elongated body 2 made of expanded plastic material and at a predetermined distance from both faces 2 a, 2 b of said body.
This additional embodiment of the composite construction elements 1 further allows to achieve improved characteristics of fire resistance in case of fire, either by coating at least in part the reinforcing section bars 7, 8 with a fire resistant film, or by arranging a suitable filling material incorporating at least one fire retardant material adapted to impart an improved fire resistance in the gap defined between the rigid covering element (where present) and the face(s) 2 a, 2 b of the elongated body 2 made of expanded plastic material.
According to the preferred embodiment illustrated in FIG. 9, the reinforcing section bars 7, 8 of the construction element 1 are substantially Z-shaped in a manner entirely similar to what has been illustrated in FIG. 8.
In this preferred embodiment, however, the reinforcing section bars 7, 8 are provided with opposite first and second lateral portions 7 b, 8 b and 7 c, 8 c respectively protruding from the opposite faces 2 a, 2 b of the elongated body 2 made of expanded plastic material.
The substantially planar faces 9, 10, 13 and 14, therefore, are extending substantially parallel to the faces 2 a and 2 b at a predetermined distance therefrom, preferably at a distance similar to that described above with reference to FIG. 8 (10-60 mm).
This additional embodiment of the composite construction elements 1, therefore, advantageously allows both to have improved characteristics of resistance to the bending loads and to support external covering elements (for example panels made of plasterboard and/or laths supporting plaster layers, not shown) at opposite parts of the elongated body 2 made of expanded plastic material and at a predetermined distance from both faces 2 a, 2 b of said body.
Also this additional embodiment of the composite construction elements 1 allows to achieve improved characteristics of fire resistance in case of fire, either by coating at least in part the reinforcing section bars 7, 8 with a fire resistant film, or by arranging a suitable filling material incorporating at least one fire retardant material adapted to impart an improved fire resistance in the gap defined between the rigid covering element (where present) and the face(s) 2 a, 2 b of the elongated body 2 made of expanded plastic material.
According to the preferred embodiment illustrated in FIG. 10, the reinforcing section bars 7, 8 of the construction element 1 are substantially Z-shaped in a manner entirely similar to what has been illustrated in FIG. 8.
In this preferred embodiment, however, the arrangement of the planar faces of the first and of the second lateral portions 7 b, 8 b and 7 c, 8 c of the reinforcing section bars 7, 8 is similar to that of FIG. 1, that is, with only the substantially planar faces 9, 10 protruding from the elongated body 2 made of expanded plastic material at a predetermined distance therefrom.
This additional embodiment of the composite construction elements 1, therefore, allows to have improved characteristics of resistance to the bending loads in addition to the technical effects already described above with reference to FIGS. 1, 8 and 9.
According to the preferred embodiment illustrated in FIG. 11, the reinforcing section bars 7 and 8 of the composite construction elements 1 (of which only the reinforcing section bar 7 is illustrated in FIG. 11 for simplicity) are substantially C-shaped and each of them comprises respective first portions 7 b, 8 b and respective second portions 7 c, 8 c substantially fin-shaped and provided with faces 9, 10 and 13, 14, preferably substantially planar, projecting in a cantilevered fashion from the central portion 7 a, 8 a of the section bars themselves.
In the preferred embodiment illustrated, the fins 7 b, 8 b and 7 c, 8 c are extending substantially perpendicular to the central portion 7 a, 8 a.
With reference to FIGS. 12 and 13, some preferred embodiments of a wall structure 28 will now be described by way of a non-limiting example, which wall structure may be realized by means of a plurality of composite construction elements 1 according to the invention, for example each incorporating a pair of substantially C-shaped reinforcing section bars 7, 8 according to the embodiment of FIG. 11.
According to the preferred embodiment of FIG. 12, the wall structure 28 comprises a plurality of composite construction elements 1 arranged side by side and each of which is provided with a pair of reinforcing section bars 7, 8 having respective first lateral portions 7 b, 8 b protruding from the face 2 a of the elongated body 2 made of expanded plastic material and provided with respective substantially planar faces 9, 10 extending substantially parallel to the face 2 a at a predetermined distance therefrom. In this case, the lateral portions 7 b, 8 b are substantially fin-shaped and are projecting in a cantilevered fashion from the central portion 7 a, 8 a of the section bars themselves.
The reinforcing section bars 7, 8 are also provided with respective second lateral portions 7 c, 8 c—also substantially fin-shaped—incorporated in the mass of expanded plastic material and provided with respective faces 13, 14, preferably substantially planar, extending substantially flush with the face 2 b of the elongated body 2.
Similarly to what has been described above with reference to the preferred embodiment of FIG. 1, the composite construction elements 1 of the wall structure 28 support a plurality of rigid covering elements, for example matchboarded wood panels indicated at 29 and a plurality of plasterboard panels indicated at 30, at opposite parts of the elongated body 2 made of expanded plastic material.
The panels 29 and 30 are fastened in a way known per se to the substantially planar faces 9, 10 and, respectively, 13, 14 of the reinforcing section bars 7, 8 for example by means of screws not shown.
Thanks to the configuration of the composite construction elements 1, a gap 31 is defined in this case between the panels 29 and the face 2 a of the elongated body 2 made of expanded plastic material, which is filled in this case with a suitable heat and sound-proofing filling material M, such as glass wool, mineral wool or a foamed polyurethane material.
The composite construction elements 1 of this embodiment advantageously achieve improved supporting and heat and sound insulation characteristics.
Finally, the wall structure 28 according to the invention can achieve improved characteristics of fire resistance in case of fire thanks to one or more of the following features:

- to the fact that the reinforcing section bars 7, 8 can be coated at least in part with a fire resistant film;
- to the fact that the rigid covering elements associated to the reinforcing section bars 7, 8 can incorporate at least one fire retardant material adapted to impart an improved fire resistance or to the fact that they can be coated at least in part with a fire resistant film;
- to the fact that the filling material M can incorporate at least one fire retardant material adapted to impart an improved fire resistance.

According to the preferred embodiment of FIG. 13, the wall structure 28 comprises a plurality of composite construction elements 1 arranged side by side, each of which is provided with a pair of reinforcing section bars 7, 8 substantially C-shaped and having respective first and second lateral portions 7 b, 8 b and 7 c, 8 c protruding from the faces 2 a and 2 b of the elongated body 2 made of expanded plastic material.
The aforementioned lateral portions 7 b, 8 b and 7 c, 8 c are provided with respective faces 9, 10 and 13, 14, preferably substantially planar, extending substantially parallel to the face 2 a and, respectively, 2 b at a predetermined distance therefrom, for example at a distance similar to that described above with reference to FIG. 8 (10-60 mm).
Similarly to the previous embodiment illustrated in FIG. 12, the lateral portions 7 b, 8 b and 7 c, 8 c of the reinforcing section bars 7, 8 are substantially fin-shaped and are projecting in a cantilevered fashion from the central portion 7 a, 8 a of the section bars themselves.
In this preferred embodiment, the faces 9, 10 and 13, 14 of the opposite lateral portions 7 b, 8 b and 7 c, 8 c of the reinforcing section bars 7, 8 support a pair of laths 32, 33 at a predetermined distance from the faces 2 a, 2 b of the elongated body 2 made of expanded plastic material so as to define two gaps 34, 35 between the laths 32, 33 and the aforementioned faces 2 a, 2 b. In this case, these gaps are not filled with any material and define respective air chambers which improve the sound insulation properties of the wall structure 28.
In the following description and in the subsequent claims, the expression: lath for supporting at least one covering layer, is used to indicate not only conventional laths having a mesh structure—either smooth or provided with protruding ribs—obtained by stretching a suitably notched metal sheet, but also any sheet-like member adapted to support a suitable covering material.
Preferably, each of the laths 32, 33 is a stretched metal lath essentially formed by a rhomb-shaped mesh having a length-to-height rhomb ratio of 2:1.
Preferably, the rhomb length varies between about 20 and about 60 mm, while the rhomb width varies between about 10 and about 30 mm.
Preferably, furthermore, such stretched laths have a thickness comprised between about 0.4 mm and about 1.0 mm and, still more preferably, comprised between about 0.4 mm and about 0.8 mm.
The laths 32, 33 support in turn at least one layer 36, 37 of a suitable covering material, such as for example plaster or cement, optionally incorporating at least one material selected from reinforcing fibers of a suitable material and at least one fire retardant material adapted to impart an improved fire resistance to the covering material, which can be applied after laying the wall structure 28.
The composite construction elements 1 of this embodiment advantageously achieve improved load-bearing characteristics, improved heat and sound insulation characteristics and improved characteristics of fire resistance thanks to the firm connection of the laths 32, 33 and of the covering material supported thereby to the reinforcing section bars 7, 8.
In an additional embodiment, not shown, the faces 9, 10 and 13, 14 of the opposite lateral portions 7 b, 8 b and 7 c, 8 c of the reinforcing section bars 7, 8 can support a pair of arc welded meshes constituted by metal reinforcement rods of a concrete casting applied outside the composite construction elements 1.
The composite construction element 1 illustrated hereinabove in some of the possible embodiments thereof, can be advantageously obtained by means of known operations for manufacturing the reinforcing section bars 7, 8 and known equipment for the continuous or discontinuous molding of the elongated body 2 made of expanded plastic material incorporating such section bars.
With reference to the preferred embodiments described above of the construction element 1, a preferred embodiment of a method according to the invention will now be described.
In a preliminary step, carried out in a way known per se, at least one sheet—preferably a pair of sheets—made of a structural rigid material, for example galvanized steel, intended to form the reinforcing section bars 7, 8, are provided.
Advantageously, the aforementioned sheets have a predetermined thickness and a width comprised, for example, between about 0.4 and 1.5 mm and, respectively, between about 140 and about 340 mm.
The sheets further comprise a central portion and a pair of lateral portions extending from axially opposite parts with respect to the central portion, which portions are intended to constitute, as it will appear more clearly hereinafter, the central portion 7 a, 8 a and, respectively, the lateral portions 7 b, 8 b and 7 c, 8 c of the reinforcing section bars 7, 8 being manufactured.
In a subsequent step, the sheets are bent in a way known per se—for example by means of a forming machine—along a pair of longitudinal bending lines substantially parallel to one another so as to form the reinforcing section bars 7, 8 comprising the first lateral portions 7 b, 8 b provided with the faces 9, 10, preferably substantially planar, extending substantially perpendicular to the central portions 7 a, 8 a of the section bars being manufactured.
Preferably, the bending step is carried out so as to form at the same time also the second lateral portions 7 c, 8 c provided with the faces 13, 14, also preferably substantially planar and extending substantially perpendicular to the central portions 7 a, 8 a of the section bars being manufactured.
In a variant of this embodiment, the faces 9, 10 and 13, 14 of the first and of the second lateral portions 7 b, 8 b and 7 c, 8 c of the reinforcing section bars 7, 8 are both extending above or both below the lying plane of the sheet.
Preferably, the bending step is carried out so that the faces 9, 10 and 13, 14 of the first and of the second lateral portions 7 b, 8 b and 7 c, 8 c of the reinforcing section bars 7, 8 form an angle of about 90° with respect to the lying plane of the sheet central portion.
Preferably, furthermore, the sheet bending step can be carried out, still using equipment known per se, so as to further bend for example at an angle equal to about 90°, the faces 9, 10 and 13, 14 so as to obtain the aforementioned first portion substantially perpendicular to the central portion 7 a, 8 a of the reinforcing section bars 7, 8 and the second end portion inclined and forming an angle of predetermined value with the aforementioned first portion.
According to additional preferred embodiments, the aforementioned bending step can be carried out by bending the sheets along at least two longitudinal bending lines substantially parallel to one another, so as to form a pair of first and second lateral portions 7 b, 8 b and 7 c, 8 c, provided with respective faces 9, 10 and 13, 14 extending at opposite parts with respect to the central portions 7 a, 8 a of the section bars being manufactured, in order to obtain the structures of the reinforcing section bars 7, 8 illustrated in FIGS. 8, 9 and 10.
In a subsequent step, the reinforcing section bars 7, 8 thus obtained are arranged in a molding seat of a suitable equipment for molding plastics, conventional per se and not shown.
Once the reinforcing section bars 7, 8 have been arranged in the molding seat, the steps of feeding expandable plastics granules into said molding seat and of expanding and then bonding together the plastics granules in the molding seat, so as to form the elongated body 2 of the construction element 1 incorporating the reinforcing section bars 7, 8, are carried out.
In a first embodiment, the step of molding the elongated body 2 made of expanded plastic material is carried out in such a way that the faces 9, 10 of the first lateral portions 7 b, 8 b of the reinforcing section bars 7, 8 protrude from the face 2 a of the elongated body 2 and extend substantially parallel to said face at a predetermined distance therefrom.
According to additional preferred embodiments, the aforementioned step of molding the elongated body 2 made of expanded plastic material is carried out in such a way that the opposite faces 13, 14 of the lateral portions 7 c, 8 c of the reinforcing section bars 7, 8 are essentially incorporated in the mass of expanded plastic material and, as such, are extending parallel to and substantially flush with the opposite face 2 b of the elongated body 2 or, alternatively, protrude from the face 2 b and extend substantially parallel to said face at a predetermined distance therefrom.
In a preferred embodiment, the method of the invention further comprises the step of forming a plurality of openings 15 in the central portion of the sheet or of the sheets from which the reinforcing section bars 7, 8 are obtained.
Preferably, such openings have a circular shape and are extending in longitudinal direction along the sheet preferably astride of the longitudinal axis of the sheet itself.
The operation of forming the openings 15 can be carried out in a way conventional per se, for example by punching.
In a preferred embodiment, the method of the invention further comprises the step of providing a fire resistant film on at least a portion of the sheet or sheets from which the reinforcing section bars 7, 8 are obtained.
Preferably, the aforementioned film is provided by means of the steps of:

- a) applying a paint selected from the group comprising intumescent paints and antifire paints on at least a portion of the sheet or sheets from which the reinforcing section bars 7, 8 are obtained; and
- b) drying said paint.

The steps a) and b) are carried out with methods and equipment known to those skilled in the art.
In an additional embodiment of the method of the invention, it is also possible to begin the manufacture of the construction element 1 starting from a pre-drilled sheet, optionally already incorporating a fire resistant film on at least a portion of the external surface thereof, wound on a reel and arranged upstream of the bending station.
If the manufacture of the construction element 1 is carried out continuously, the method finally provides for a final step, also carried out by means of equipment known per se, in which the body 2 is cut to size so as to obtain a construction element having the desired length.
In this way, it is possible to obtain the structures of construction element 1 illustrated in FIGS. 1-13.
Clearly, a man skilled in the art may introduce modifications and variants to the invention described hereinbefore in order to meet specific and contingent application requirements, variants and modifications which anyway fall within the scope of protection as defined in the attached claims.

Claims

1. A composite construction element (1) comprising:

b) at least one reinforcing section bar (7, 8) longitudinally extending in said at least one elongated body (2) and having a first lateral portion (7 b, 8 b) protruding from a first face (2 a) of said opposite faces (2 a, 2 b) of the elongated body (2);

wherein said first lateral portion (7 b, 8 b) is provided with a face (9, 10) extending substantially parallel to said first face ( 2 a) of said at least one elongated body (2) made of expanded plastic material at a predetermined distance therefrom.

2. A construction element (1) according to claim 1, wherein said at least one reinforcing section bar (7, 8) is substantially shaped as an L, a C, a Z or an I.

3. A construction element (1) according to claim 1, wherein said at least one reinforcing section bar (7, 8) is provided with a second lateral portion (7 c, 8 c) provided with a face (13, 14) extending substantially parallel to the second face (2 b) of said opposite faces (2 a, 2 b) of the elongated body (2) made of expanded plastic material.

4. A construction element (1) according to claim 3, wherein said second lateral portion (7 c, 8 c) of said at least one reinforcing section bar (7, 8) is extending flush with said second face (2 b) of the elongated body (2) made of expanded plastic material.

5. A construction element (1) according to claim 3, wherein said second lateral portion (7 c, 8 c) of said at least one reinforcing section bar (7, 8) is entirely incorporated in the mass of expanded plastic material and is arranged at a predetermined distance from said second face (2 b) of the elongated body (2) made of expanded plastic material.

6. A construction element (1) according to claim 3, wherein said second lateral portion (7 c, 8 c) of said at least one reinforcing section bar (7, 8) protrudes from said second face (2 b) of the elongated body (2) made of expanded plastic material and wherein said face (13, 14) of said second lateral portion (7 c, 8 c) is extending substantially parallel to said second face (2 b) of the elongated body (2) made of expanded plastic material at a predetermined distance therefrom.

7. A construction element (1) according to claim 1, wherein said face (9, 10) of the first lateral portion (7 b, 8 b) or said face (13, 14) of the second lateral portion (7 c, 8 c) of said at least one reinforcing section bar (7, 8) is substantially planar.

8. A construction element (1) according to claim 1, wherein said first (7 b, 8 b) or said second (7 c, 8 c) lateral portion of said at least one reinforcing section bar (7, 8) is substantially shaped as a C or as an upturned U.

9. A construction element (1) according to claim 1, wherein said face (9, 10, 13, 14) of said first (7 b, 8 b) or said second (7 c, 8 c) lateral portion of said at least one reinforcing section bar (7, 8) is substantially perpendicular to a central portion (7 a, 8 a) of the reinforcing section bar (7, 8).

10. A construction element (1) according to claim 1, wherein said first (7 b, 8 b) or said second (7 c, 8 c) lateral portion of said at least one reinforcing section bar (7, 8) is substantially hook-shaped.

11. A construction element (1) according to claim 1, wherein said first (7 b, 8 b) or said second (7 c, 8 c) lateral portion of said at least one reinforcing section bar (7, 8) is associated to a longitudinal rib (41, 42) projecting in a cantilevered fashion from said first (2 a) or from said second (2 b) face of the elongated body (2) made of expanded plastic material.

12. A construction element (1) according to claim 11, wherein said face (9, 10, 13, 14) of said first (7 b, 8 b) or of said second (7 c, 8 c) lateral portion of said at least one reinforcing section bar (7, 8) is extending at least in part substantially flush with an upper face (41 a, 42 a) of said longitudinal rib (41, 42) of the elongated body (2) made of expanded plastic material.

13. A construction element (1) according to claim 1, comprising at least two reinforcing section bars (7, 8) longitudinally extending in the elongated body (2) made of expanded plastic material at opposite parts of the longitudinal center plane of said body along a direction substantially parallel to said center plane.

14. A construction element (1) according to claim 13, wherein at least a first (7) of said reinforcing section bars is provided with a respective first lateral portion (7 b) protruding from said first face (2 a) of the elongated body (2) made of expanded plastic material and wherein at least a second (8) of said reinforcing section bars is provided with a respective lateral portion (8 c) protruding from the second face (2 b) of said opposite faces (2 a, 2 b) of the elongated body (2), said lateral portion (8 c) of said at least one second reinforcing section bar (8) being provided with a face (14) extending substantially parallel to said second face (2 b) of the elongated body (2) made of expanded plastic material at a predetermined distance therefrom.

15. A construction element (1) according to claim 13, wherein said reinforcing section bars (7, 8) are provided with opposite first (7 b, 8 b) and second (7 c, 8 c) lateral portions protruding from said opposite faces (2 a, 2 b) of the elongated body (2) made of expanded plastic material.

16. A construction element (1) according to claim 3, wherein said second lateral portions (7 c, 8 c) of the reinforcing section bars (7, 8) are extending at opposite parts of the longitudinal center plane of said elongated body (3).

17. A construction element (1) according to claim 1, wherein said face (9, 10, 13, 14) of said first (7 b, 8 b) or of said second (7 c, 8 c) lateral portion of said at least one reinforcing section bar (7, 8) is provided with at least one stiffening rib (45, 46).

18. A construction element (1) according to claim 1, wherein said at least one reinforcing section bar (7, 8) is provided with a plurality of openings (15) formed in a central portion (7 a, 8 a) thereof.

19. A construction element (1) according to claim 1, wherein said at least one reinforcing section bar (7, 8) is coated at least in part with a fire resistant film obtained from a paint selected from the group comprising intumescent paints and antifire paints.

20. A construction element (1) according to claim 1, further comprising a covering element (11, 29, 32) associated to said face (9, 10) of the first lateral portion (7 b, 8 b) of said at least one reinforcing section bar (7, 8).

21. A construction element (1) according to claim 1, further comprising a covering element (12, 30, 33) associated to the second face (2 b) of said opposite faces (2 a, 2 b) of the elongated body (2) made of expanded plastic material or to said face (13, 14) of the second lateral portion (7 c, 8 c) of said at least one reinforcing section bar (7, 8).

22. A construction element (1) according to claim 14, further comprising a covering element associated to said face (9, 10, 13, 14) of the lateral portions (7 b, 8 b, 7 c, 8 c) of said reinforcing section bars (7, 8) protruding from the opposite faces (2 a, 2 b) of the elongated body (2) made of expanded plastic material.

23. A construction element (1) according to claim 20, wherein said covering element comprises a lath (32, 33) and at least one layer (36, 37) of a suitable covering material supported by said lath (32, 33).

24. A construction element (1) according to claim 23, wherein said covering material is plaster or cement optionally incorporating a material selected from reinforcing fibers of a suitable material and at least one fire retardant material adapted to impart an improved fire resistance to said covering material.

25. A construction element (1) according to claim 20, wherein said covering element comprises a substantially reticular reinforcement metal structure (20) and at least one concrete layer supported by said reinforcement structure (20).

26. A construction element (1) according to claim 20, wherein said covering element comprises a rigid panel (11, 12, 29, 30).

27. A construction element (1) according to claim 26, wherein said rigid panel (11, 12, 29, 30) is a panel of plasterboard, wood, rigid plastic material or other suitable material optionally incorporating at least one fire retardant material adapted to impart an improved fire resistance to said rigid panel (11, 12, 29, 30).

28. A construction element (1) according to claim 27, wherein said rigid panel (11, 12, 29, 30) is coated at least in part with a fire resistant film obtained from a paint selected from the group comprising intumescent paints and antifire paints.

29. A construction element (1) according to claim 1, wherein said at least one reinforcing section bar (7, 8) is longitudinally extending in said at least one elongated body (2) made of expanded plastic material along substantially the entire length thereof.

30. A construction element (1) according to claim 2 further comprising a filling material interposed between said covering element and said elongated body (2) made of expanded plastic material.

31. A construction element (1) according to claim 30, wherein said filling material incorporates at least one fire retardant material adapted to impart an improved fire resistance to said covering material.

32. A method for manufacturing a construction element (1) according to claim 1, comprising the steps of:

a) providing at least one sheet made of a rigid material having predetermined thickness and width, said at least one sheet having a central portion and a pair of lateral portions extending at opposite parts of said central portion;

b) bending said at least one sheet along at least one longitudinal bending line so as to form at least one reinforcing section bar (7, 8) comprising a first lateral portion (7 b, 8 b) provided with a face (9, 10) extending substantially perpendicular to the central portion;

c) arranging said at least one reinforcing section bar (7, 8) thus obtained in a molding seat of a suitable equipment for molding plastics;

d) feeding expandable plastics granules into said molding seat;

e) expanding and then bonding together the plastics granules in said molding seat, so as to form an elongated body (2) made of expanded plastic material provided with opposite faces (2 a, 2 b) and incorporating at least partly said at least one reinforcing section bar (7, 8);

said step e) being carried out so that the face (9, 10) of said at least one first lateral portion (7 b, 8 b) of said at least one reinforcing section bar (7, 8) protrudes from a first face (2 a) of said opposite faces (2 a, 2 b) of the elongated body (2) made of expanded plastic material and extends substantially parallel to said first face (2 a) at a predetermined distance therefrom.

33. A method according to claim 32, wherein said bending step b) is carried out so as to bend said at least one sheet along at least two longitudinal bending lines so as to form at least one reinforcing section bar (7, 8) further comprising a second lateral portion (7 c, 8 c) provided with a respective face (13, 14) extending substantially perpendicular to the central portion of said at least one sheet.

34. A method according to claim 33, wherein said bending step b) is carried out by bending said at least one sheet along at least two longitudinal bending lines substantially parallel to one another so as to form a pair of first (7 b, 8 b) and second (7 c, 8 c) lateral portions provided with respective faces (9, 10; 13, 14) extending at opposite parts with respect to the central portion of said at least one sheet.

35. A method according to claim 33, wherein the faces (9, 10; 13, 14) of said first (7 b, 8 b) and of said second lateral portion (7 c, 8 c) of said at least one reinforcing section bar (7, 8) are both extending above or both below the lying plane of the sheet.

36. A method according to claim 33, wherein said step e) is carried out so that the face (13, 14) of said second lateral portion (7 c, 8 c) of the reinforcing section bar (7, 8) is incorporated in the expanded plastic material and is extending flush with and substantially parallel to the second face (2 b) of said elongated body (2) made of expanded plastic material.

37. A method according to claim 33, wherein said step e) is carried out so that said second lateral portion (7 c, 8 c) of said at least one reinforcing section bar (7, 8) protrudes from said second face (2 b) of the elongated body (2) made of expanded plastic material and wherein said face (13, 14) of said second lateral portion (7 c, 8 c) is extending substantially parallel to the second face (2 b) of the elongated body (2) made of expanded plastic material at a predetermined distance therefrom.

38. A method according to claim 32, further comprising the step of forming a plurality of openings (15) in the central portion of the sheet.

39. A method according to claim 32, further comprising the step of providing a fire resistant film on at least a portion of said at least one sheet.

40. A method according to claim 39, wherein said film is provided by means of the steps of: a) applying a paint selected from the group comprising intumescent paints and antifire paints on at least a portion of said at least one sheet and b) drying said paint.

41. A floor structure (18) comprising at least one construction element (1) according to claim 1.

42. A wall structure (28) comprising at least one construction element (1) according to claim 1.