EP4095315A1

EP4095315A1 - Beam for self-supporting structures

Info

Publication number: EP4095315A1
Application number: EP22173690.3A
Authority: EP
Inventors: Stefano China; Franco Daniele
Original assignee: Tecnostrutture Srl
Current assignee: Tecnostrutture Srl
Priority date: 2021-05-25
Filing date: 2022-05-17
Publication date: 2022-11-30
Anticipated expiration: 2042-05-17
Also published as: EP4095315C0; EP4095315B1; IT202100013550A1

Abstract

Beam (10) for self-supporting structures, comprising a base plate (11) surmounted by a plurality of reinforcement trellises (12) and by at least one lightening element (13) in which an empty chamber (15) is made.

Description

FIELD OF THE INVENTION

The present invention concerns a beam for the construction of self-supporting structures, in particular for the construction of bridges. In particular, the beam is a self-supporting beam made of steel or mixed steel-concrete.
The invention also concerns a self-supporting structure, in particular for the construction of bridges, provided with one or more of such beams. The self-supporting structures that can be made using this beam are used in particular for the construction of pedestrian or road bridges with medium-long spans, that is, from about 10 m to about 22 m.

BACKGROUND OF THE INVENTION

In the construction of structures such as pedestrian or road bridges it is known to use constituent elements, such as bridge slabs and beams, which are produced separately and subsequently installed on the site where the structure is laid.
This solution, which provides the separate use of bridge beams and slabs, while ensuring satisfactory performance of the deck that will form the structure of the bridge, makes construction site operations costly and excessively dilated over time. The elements that make up the bridge are in fact not connected to each other and are joined together only after the concrete is cast.
Alternatively, there are technologies for the construction of bridges with "prefabricated segments" which, however, are not applicable in complex situations, for example if the construction site is characterized by limited operating spaces, or are inconvenient from an economic point of view, for example in the case of construction of structures of limited size that do not justify the fixed costs of setting up the building site.
Beams for self-supporting structures for known bridges are therefore structurally complex, bulky and make it rather difficult to inspect the structure once made. Known beams also have a considerable weight, mainly due to the weight of the concrete which is cast to complete the structure.
There is therefore a need to perfect a beam for self-supporting structures which can overcome at least one of the disadvantages of the state of the art.
In particular, one purpose of the present invention is to provide a beam for self-supporting structures, in particular for the construction of bridges, which is compact and structurally simple compared with beams for bridges known in this field.
Another purpose of the present invention is to provide a beam for self-supporting structures which arrives in the construction site equipped with all the structural elements necessary for its installation, therefore requiring much faster and simpler installation operations compared with the beams known in this field.
Another purpose of the present invention is to provide a beam for self-supporting structures which allows to save considerable quantities of concrete for casting and therefore to considerably reduce the weight of the bridge structure made using this beam.
Another purpose of the present invention is to provide a self-supporting structure, in particular for the construction of bridges, which uses one or more beams and is characterized by constructive simplicity, lightness and compactness.
The Applicant has devised, tested and embodied the present invention to overcome the shortcomings of the state of the art and to obtain these and other purposes and advantages.

SUMMARY OF THE INVENTION

The present invention is set forth and characterized in the independent claims. The dependent claims describe other characteristics of the present invention or variants to the main inventive idea.
In accordance with the above purposes and according to the present invention, a beam for self-supporting structures comprises a base plate surmounted by a plurality of reinforcement trellises and by at least one lightening element which is provided with an empty chamber which extends substantially for the entire length of the box-like body.
The beam also comprises another trellis, which surmounts the lightening element and connects the pair of trellises.
The beam also comprises at least one spacer positioned between the lightening element and the other trellis.
Advantageously, the present beam is compact, structurally simple compared to known beams and, thanks to the at least one lightening element with which it is equipped, it allows to obtain a self-supporting structure with a significantly lower weight than the structures made using known beams. Self-supporting structures made using one or more suitably connected beams can weigh up to 40% less than traditional structures. This is mainly due to the considerable amounts of concrete that are saved during casting, since the chamber inside the lightening element is not filled with concrete.
Advantageously, moreover, the presence of another trellis attached both to the lateral trellises and also to the lightening element by means of the spacer allows to significantly increase the overall stability of the beam.
The present beam also arrives at the construction site already equipped with all the structural elements necessary for its installation, that is, the plate, the trellises and the lightening element, therefore it requires much faster and simpler installation operations than beams known in the field.
Furthermore, the chamber made inside the lightening element can be used for the installation of systems for monitoring the built structure, for inspections or other.
According to another aspect of the invention, the lightening element can extend substantially for the entire length of the beam.
The trellises can be directed in the same direction and the lightening element can be directed parallel to the trellises .
The lightening element can comprise a lower aperture positioned in correspondence with the plate, a pair of opposite lateral walls and an upper wall opposite to the lower aperture.
Furthermore, the lightening element can comprise a pair of strips for connection with the plate and which are positioned in correspondence with the ends of the lateral walls that are facing the plate.
The lightening element can have a trapezoidal shape in cross-section.
According to another aspect of the present invention, the spacer is positioned between the upper wall of the lightening element and the other trellis.
According to another aspect of the present invention, the other trellis is attached to the trellises located on the sides of the lightening element and it is at least resting, preferably it is also attached in a stable way, on the at least one spacer.
According to another aspect of the present invention, both the lightening element and also the trellises are attached to the plate.
The present invention also concerns a bridge structure comprising a beam as defined above or a plurality of beams as defined above disposed side by side and reciprocally connected along joint lines.

DESCRIPTION OF THE DRAWINGS

These and other aspects, characteristics and advantages of the present invention will become apparent from the following description of some embodiments, given as a non-restrictive example with reference to the attached drawings wherein:

fig. 1 is a three-dimensional view of a self-supporting structure formed by a plurality of beams according to the present invention;
fig. 2 is a lateral view of the present self-supporting structure;
fig. 3 is a front view of the present self-supporting structure;
fig. 4 is a front view of a lightening element.

To facilitate comprehension, the same reference numbers have been used, where possible, to identify identical common elements in the drawings. It is understood that elements and characteristics of one embodiment can be conveniently combined or incorporated into other embodiments without further clarifications.

DESCRIPTION OF SOME EMBODIMENTS

We will now refer in detail to the possible embodiments of the invention, of which one or more examples are shown in the attached drawings, by way of a non-limiting example. The phraseology and terminology used here is also for the purposes of providing non-limiting examples.
With reference to the attached drawings, fig. 1 shows a self-supporting structure 22 according to the present invention, in particular for the construction of bridges, formed by a plurality of beams 10 located side by side and reciprocally connected along joint lines 23. The joint lines 23 can be directed according to a longitudinal direction L of the self-supporting structure 22.
The reciprocal connection between the beams 10 along the joint lines 23 can be achieved by means of welding or removable attachment means such as bolted plates or suchlike.
In the example shown in fig. 1, we have hypothesized a self-supporting structure 22 with a width equal to the sum of the widths W of each single beam 10. Alternatively, it would be possible to provide that the self-supporting structure 22 comprises even just a single beam 10, in the event the self-supporting structure 22 to be built requires a width substantially equal to the width W.
The self-supporting structure 22 can be built by adopting a static, isostatic or hyperstatic scheme.
The beam 10 comprises a base plate 11 surmounted by a plurality of reinforcement trellises 12 and by at least one lightening element 13 which is provided with a box-like body 14 in which an empty chamber 15, which extends substantially along the entire length of the box-like body 14, is created.
The lightening element 13 is a distinct and separate component with respect to the plate 11.
The lightening element 13 is attached to the plate 11. Therefore, the lightening element 13 cooperates structurally, improving the bending behavior of the beam 11.
The plate 11 can be made of a metallic material, for example carpentry steel.
The lightening element 13 can extend substantially for the entire length of the beam 10.
No concrete is inserted in the chamber 15 during the casting that completes the self-supporting structure 22 to one or more beams 10, thus achieving a considerable lightening of the beam 10 and ultimately a considerable lightening of the self-supporting structure 22. Furthermore, the chamber 15 can be used to insert plants or systems for monitoring the preservation of the self-supporting structure 22 over time. The chamber 15 can also be easily accessed and inspected.
The lightening element 13 can extend substantially for the entire length of the beam 10, thus allowing, by means of the chamber 15 with which it is provided, to obtain a significant empty volume that is not occupied by concrete.
The trellises 12 can be directed in the same direction L, see for example figs. 1 and 2, and the lightening element 13 can be directed parallel to the trellis 12. The lightening element 13 can be positioned between a pair of trellises 12.
The pair of trellises 12 can also be connected by another trellis 16 that surmounts the lightening element 13 which is positioned between the pair of trellises 12. Therefore, the other trellis 16 is attached to both trellises 12.
As can be seen in fig. 3, the trellises 12 located on the sides of the lightening element 13 can be directed in a substantially vertical direction, while the other trellis 16 located in order to connect the pair of trellises 12 can be directed in a substantially horizontal direction.
The trellises 12 are attached to the plate 11.
The trellises 12 located on the sides of the lightening element 13 are higher than the lightening element 13, with respect to the reference constituted by the plate 11. The trellises 12 located on the sides of the lightening element 13 have the same height.
Furthermore, the beams 10 of the self-supporting structure 22 can be positioned with a regular pitch X with respect to a transverse direction B of the beam, so as to give greater balance to the structure.
Fig. 4 shows a lightening element 13 which can comprise a lower aperture 17 which is configured to be positioned in correspondence with the plate 11, a pair of opposite lateral walls 18 and an upper wall 19, which is opposite to the lower aperture 17. Substantially, therefore, the upper surface of the plate 11 represents the lower closing side of the chamber 15 of the lightening element 13.
The lightening element 13 can also comprise a pair of strips 20 for connection with the plate 11, which are positioned in correspondence with the ends of the lateral walls 18 that face toward the plate 11.
The strips 20 can therefore be created along the entire extension of the lightening element 13 and they can be connected to the plate 11 by welding or another connection system.
The lightening element 13 can have a trapezoidal cross-section. The trapezoidal shape allows a more effective reduction of the stresses on the beam 10; however, it is possible to also use lightening elements 13 with other cross-sections, for example square or rectangular.
In particular, the larger base of the trapezoid defined by the cross-section is represented by the lower aperture 17 positioned on the plate 11, while the smaller base is defined by the upper wall 19. Preferably, the trapezoid is an isosceles trapezoid, therefore the lateral walls 18 are congruent.
The beam 10 can also comprise at least one spacer 21 positioned between the upper wall 19 and the other trellis 16, in such a way as to be able to substantially vary the height of the beam 10 by varying the distance between the other trellis 16 and the lightening element 13. As can be seen in fig. 1, a plurality of spacers 21 located in sequence along the upper wall 19 can be associated with each of the lightening elements 13 of the self-supporting structure 22.
Therefore, each spacer 21 is positioned between the lightening element 13 and the other trellis 16 that connects the lateral trellises 12. The spacer 21 is located in contact both with the lightening element 13, on which it rests in a stable manner, that is, attached/integral, and also with the other trellis 16.
The other trellis 16 is resting on the spacers 21. Possibly, the other trellis 16 can also be made integral with the spacers 21.
Advantageously, the other trellis 16 resting on the spacers 21 and the latter resting on the lightening element 13 allows to significantly increase the structural stability of the beam 10.
The spacers 21 also allow to position other reinforcements between the lightening element 13 and the other trellis 16.
The lightening element 13 can be made in a single body.
The lightening element 13 can be made of metallic material, such as steel or suchlike, or of plastic material. If it is made of metallic material, the lightening element can be created by shaping a section bar, and then connected to the plate 11 by welding or other attachment system, for example by welding of the strips 20.
If it is made of plastic material, the lightening element 13 can be created through extrusion or other.
The beam 10 shown by way of example comprises a single lightening element 13; however, it would be possible to provide, for example as a function of the width W of the beam 10, a plate 11 provided with several lightening elements 13 located side by side and/or alternating with the trellises 12.
It is clear that modifications and/or additions of parts may be made to the beam 10 for self-supporting structures as described heretofore, without departing from the field and scope of the present invention, as defined by the claims.
In the following claims, the sole purpose of the references in brackets is to facilitate reading and they must not be considered as restrictive factors with regard to the field of protection claimed in the specific claims.

Claims

Beam (10) for self-supporting structures, characterized in that it comprises a base plate (11) surmounted by a plurality of reinforcement trellises (12) and by at least one lightening element (13) positioned between a pair of said trellises (12) and provided with an empty chamber (15) which extends substantially for the entire length of said lightening element (13), said beam (10) also comprising another trellis (16), which surmounts said lightening element (13) and connects said pair of trellises (12), and at least one spacer (21) positioned between said lightening element (13) and said other trellis (16).
Beam (10) as in claim 1, characterized in that said lightening element (13) extends substantially for the entire length of the beam (10).
Beam (10) as in claim 1 or 2, characterized in that said trellises (12) are directed in a same direction (L) and said lightening element (13) is directed parallel to said trellises (12).
Beam (10) as in any claim hereinbefore, characterized in that said lightening element (13) comprises a lower aperture (17) positioned in correspondence with said plate (11), a pair of opposite lateral walls (18) and an upper wall (19) opposite said lower aperture (17).
Beam (10) as in claim 4, characterized in that said lightening element (13) comprises a pair of strips (20) for connection with said plate (11) and which are positioned in correspondence with the ends of said lateral walls (18) facing toward said plate (11).
Beam (10) as in claims 4 or 5, characterized in that said spacer (21) is positioned between said upper wall (19) of the lightening element (13) and said other trellis (16).
Beam (10) as in any claim hereinbefore, characterized in that said lightening element (13) has a trapezoidal shape in cross-section.
Beam (10) as in any claim hereinbefore, characterized in that said other trellis (16) is attached to said trellises (12) and is at least resting on said at least one spacer (21).
Beam (10) as in any claim hereinbefore, characterized in that both said lightening element (13) and also said trellises (12) are attached to said plate (11).
Self-supporting structure (22), comprising one or more beams (10) as in any claim hereinbefore disposed side by side and reciprocally connected along joint lines (23).