EP4012133B1

EP4012133B1 - Corrugated sheet metal for making high-stability waterproof surfaces and coatings

Info

Publication number: EP4012133B1
Application number: EP21212885.4A
Authority: EP
Inventors: Arsenio Borgnini
Original assignee: Profilumbra SpA
Current assignee: Profilumbra SpA
Priority date: 2020-12-09
Filing date: 2021-12-07
Publication date: 2022-12-07
Anticipated expiration: 2041-12-07
Also published as: IT202000006791U1; EP4012133A1

Description

The present patent application relates to a corrugated sheet metal suitable for making high-stability waterproof insulating surfaces and coatings, such as, for example, roof coverings for industrial warehouses made with prefabricated reinforced concrete structures and the like.
The prefabricated reinforced concrete elements used for the construction of roof coverings of industrial warehouses and the like need to be coated on the top with waterproof insulating elements.
In the prior art, such an effect is generally achieved by using the corrugated sheet metal that is commonly available on the market, which is positioned and fixed above the reinforced concrete structure (either directly or with the interposition of spacers).
Where required, a layer of insulating material (rock wool or the like) is disposed under the corrugated sheet metal for the insulation of the structure.
For the sake of clarity, it should be noted that the expression "corrugated sheet metal" refers to a sheet metal - usually distributed in sheets - that is provided on its surface with a regular alternation of ribs and grooves with an omega-shaped section.
In spite of being very popular, the use of traditional sheet metal is impaired by some practical drawbacks, the most important of which being the way in which several adjacent sheets of such corrugated sheet metal are connected and fixed in order to cover a large surface with a plurality of such sheets.
So far, such a connection is performed by laying one or more of the final frets of each sheet of such a corrugated sheet metal upon one or more of the initial frets of the immediately adjacent sheet, as the case may be.
In order to better illustrate such a traditional technology, reference should be made to the appended drawing defined as "PRIOR ART", where Fig. 1 is a schematic view of the way in which the last fret (GU) of a sheet (F1) of corrugated sheet metal is exactly coupled with the first fret (GP) of a similar sheet (F2) of corrugated sheet metal.
As shown graphically, the final frets (GU, GP) of said sheets (F1, F2) are provided with a section having a first sloping edge (BI1) connected with a flat wall (PP), which in turn is connected with a second sloping edge (BI2) having the same angle of inclination as the first sloping edge (BI1), but a considerably lower height.
When the two sheets (F1, F2) of corrugated sheet metal are overlapped partially, in particular, the second sloping edge (BI2) of the last fret (GU) of the sheet (F1) is brought in contact with the external surface of the first sloping edge (BI1) of the first fret (GP) of the back sheet (F2) and the second sloping profile (BI2) of the first fret (GP) of the sheet (F2) is brought in contact with the internal surface of the first sloping profile (PI1) of the last fret (GU) of the sheet (F1), whereas the flat wall (PP) of the sheet (F1) is brought in contact with the flat wall (PP) of the sheet (F2).
Such a perfect prismatic coupling between the frets of the sheet (F1) and the frets of the other sheet (F2) should guarantee a hermetic seal against rainwater in correspondence of the various junction points provided between a plurality of sheets of corrugated sheet metal used for covering a large roof surface.
After coupling the sheets (F1, F2) of corrugated sheet metal, possibly also with the interposition of seals, the sheets (F1, F2) are finally stabilized by means of screws or the like.
As anticipated, however, such a technology is actually impaired by some severe functional problems.
The first one of said problems is related with the poor rigidity of the junction realized between two adjacent sheets of corrugated sheet metal, it being evident that such a negative characteristic - which occurs in correspondence of all junction points of a large covering realized with a plurality of sheets of corrugated sheet metal - limits exponentially the total rigidity of such a large covering.
The second problem is related with the fact that the compressive strength of the junction points between two adjacent sheets of corrugated sheet metal is almost null.
Such a fact is a great limitation for the large coverings realized with multiple sheets of corrugated sheet metal.
In fact, if a worker in charge of laying or maintaining such a large covering surface were to walk, even accidentally, on one or more of said junction points between two adjacent sheets of corrugated sheet metal, a traumatic deformation of the sheets would be produced by compression, thus compromising the hermetic seal and consequently the impermeability of said covering.
CA1259466A discloses a corrugated sheet metal according to the preamble of claim 1 and the preamble of claim 3.
Based on such premises, the specific purpose of the present invention is to provide a sheet of corrugated sheet metal configured in such a way that, after being coupled with an identical sheet of corrugated sheet metal, it can guarantee a high rigidity in the junction point, together with a considerable compressive strength, in such a way that the large covering surface obtained by laying more sheets of the corrugated sheet metal according to the invention can be walked over.
An additional purpose of the present invention is to guarantee the perfect waterproofing of said covering, due to the hermetic seal guaranteed by said innovative sheet of corrugated sheet metal in every condition in correspondence with the junction point with the other adjacent sheets.
The last purpose of the present invention is to disclose a corrugated sheet metal provided with the aforesaid advantageous properties, even in the presence of significantly low production costs.
These purposes have been achieved by providing that the corrugated sheet metal according to the invention adopts an innovative shape in correspondence of its two lateral edges, as defined in the claims, in such a way that, in addition to ensuring a perfect prismatic coupling between two adjacent sheets of such corrugated sheet metal, the point where such a prismatic coupling is generated has a high load-bearing capacity that allows such a corrugated sheet to withstand any compressive stress.
For the sake of clarity, the description of the invention continues with reference to the attached drawings, which have only illustrative and not limiting value, wherein:

Fig. 2 is a sectional view of a first embodiment of the new corrugated sheet metal according to the present invention;
Fig. 2A is an enlarged view of the two lateral edges of the corrugated sheet metal of Fig. 2;
Fig. 2B is an axonometric view of the detail of Fig. 2A;
Fig. 2C shows the coupling mode of two adjacent sheets of the corrugated sheet metal of Fig. 2;
Fig. 2D is similar to the previous figure, except for it shows the presence of a bolt suitable for additionally stabilizing the coupling shown in Fig. 2C;
Fig. 3 shows a second embodiment of the new corrugated sheet metal according to the present invention;
Fig. 3A shows the coupling between two adjacent sheets of the corrugated sheet metal of Fig. 3;
Fig. 4 is a sectional view of a third embodiment of the new corrugated sheet metal which is not part of the present invention;
Fig. 4A shows the coupling between two adjacent sheets of the corrugated sheet metal of Fig. 4;
Fig. 5 shows a fourth embodiment of the new corrugated sheet metal which is not part of the present invention, during its coupling with an identical adjacent sheet;
Fig. 5A is similar to the previous figure, except for it shows a bolt suitable for additionally stabilizing the coupling of the two adjacent sheets of the corrugated sheet metal of Fig. 5;
Figs. 6 and 6A show the coupling between two adjacent sheets of two equivalent versions of a fifth embodiment of the new corrugated sheet metal which is not part of the present invention, with the additional provision of a bolt suitable for stabilizing such a coupling.

With reference to Fig. 2, the sheet metal (1) according to invention is usually provided with an equidistant set of frets (G), preferably with a trapezoidal shape, which protrudes from the respective flat surfaces (SP).
However, its peculiarity consists in the special configuration of the first lateral edge and of the second lateral edge.
In particular, the first one of said lateral edges is configured as a stiffening profile (10) provided with a high compressive strength in a perpendicular direction to the sheet metal (1).
Said stiffening profile (10) protrudes from the flat surface (SP) of the sheet metal (1) on the same side from which said frets (G) protrude, in parallel position to said frets (G).
On the other hand, the second one of said lateral edges of the sheet metal (1) according to the invention is configured as a longitudinal housing profile (20), with suitable shape and dimensions to exactly accommodate said box-shaped stiffening profile (10) of an adjacent identical sheet of the corrugated sheet metal (1).
Figs. 2A to 2D show the geometric configuration and the functional characteristics of the first embodiment of the sheet metal (1) according to the invention.
In particular, the stiffening profile (10) of said sheet metal (1) obtained in correspondence with the first lateral edge comprises:

an inclined wing (11) that protrudes from said flat surface (SP) of the sheet metal (1)
a flat wall (12) supported at the end of said inclined wing (11) in a parallel position to said flat surface (SP) of the sheet metal (1)
a U-shaped profile (13) with substantially square section that extends from the inner face of said flat wall (12) and is provided with a height such that its rear end (13a) is flush with said flat surface (SP) of the sheet metal (1).

On the other hand, the corresponding housing profile (20) obtained in correspondence with the second lateral edge of said corrugated sheet metal (1) comprises:

a first inclined wing (21) that protrudes from said flat surface (SP) of the corrugated sheet metal (1) with a height and inclination equal to those of said inclined wing (11) of the stiffening profile (10), with respect to which, however, it is directed towards the opposite side
a flat wall (22) supported at the end of said first inclined wing (21) in parallel position to said flat surface (SP) of the corrugated sheet metal (1) and at a height that corresponds exactly to the one occupied by said flat wall (12) of the stiffening profile (10)
a second inclined wing (23) that protrudes from the opposite side of said flat wall (22) with a corresponding opposite inclination to that one of said first inclined wing (21), with respect to which it has a lower height.

With reference to Fig. 2B, the coupling between two adjacent sheets of the first embodiment of the corrugated sheet metal (1) according to the invention can be perfected on the sole condition of exactly lowering said housing profile (20) provided on the second lateral edge of a first sheet of said corrugated sheet metal (1) onto said stiffening profile (10) provided on the first lateral edge of a second sheet of said corrugated sheet metal (1).
It is easy to understand how, after being coupled as illustrated above, the two sheets of the corrugated sheet metal (1) realize a portion of a covering made of corrugated sheet metal, which is suitable for being laid on a concrete structure.
In view of the above, it is easy to understand that said stiffening profile (10) of the corrugated sheet metal (1) is suitable for being disposed on the back of said covering, so as to be brought in contact - in coplanar position with the rear face of the flat surface (SP) of said corrugated sheet metal (1) - with the surface of such a covering, said surface being made of cement or metal carpentry.
In view of the fact that such a stiffening profile (10) is provided with said anti-compression properties, evidently, if an operator accidentally walked over the junction point of two adjacent sheets of the corrugated sheet metal (1), in correspondence with said housing profile (20) that protrudes from the sheet disposed in the front, the stiffening profile (10) of the sheet disposed in the back would be perfectly able to withstand such a compression stress because it would advantageously exploit the backing action exerted by the cement surface in favor of the rear wall (13a) of the U-shaped profile (13) of said stiffening profile (10).
It is precisely such a compressive strength of said stiffening profile (10) that excludes the possibility of causing any deformation in said junction point of the two adjacent sheets of the sheet metal (1), which could otherwise originate a leakage section for rainwater.
Fig. 2D shows a solution provided to additionally stabilize the coupling of the housing profile (20) of a sheet of the corrugated sheet metal (1) with the stiffening profile (10) of an adjacent sheet of the same sheet metal (1).
According to such a solution, an omega-shaped bolt (30) is exactly superimposed on said housing profile (20) of the sheet of the corrugated sheet metal (1), before being fixed in such a position with a screw (V1) capable of crossing the flat wall (22) of the housing profile (20) of the sheet of the corrugated sheet metal (1) disposed in the front and the flat wall (12) of the stiffening profile (10) of the sheet of the corrugated sheet metal (1) disposed in the back.
With reference to Figs. 3 and 3A, the second embodiment of the corrugated sheet metal (1A) corresponds functionally and constructively to the first embodiment, as shown in Figs. 2 to 2D.
The only difference consists in the shape of the U-shaped profile (14), which no longer has a substantially square section (as in the first embodiment of the invention), but a right trapezoidal section, it being provided with a flat end (14A) at the back, suitable for being flush with the flat surface (SP) of the corrugated sheet metal (1A).
With reference to Figs. 4 and 4A, the third embodiment of the corrugated sheet metal which is not part of the invention (1B) is characterized by the fact that the stiffening profile (10) comprises a small edge (15) that projects perpendicularly from said first lateral edge of said corrugated sheet metal (1B), whereas the housing profile (20) provided in correspondence of the second lateral edge of said sheet metal (1B) consists of a longitudinal seat, with a substantially inverted-U shape, suitable for exactly embracing the upper border of said edge (15) of the stiffening profile (10) of an adjacent sheet of corrugated sheet metal (1B).
More precisely, said longitudinal seat is obtained in correspondence of a respective edge (25) that projects perpendicularly from said second lateral edge of the sheet metal (1B) and ends with a 180°-curved edge (25a) facing the exterior of the sheet metal (1B).
The function of said curved edge (25a) is that of connecting said edge (25) with a short plate (25b) that can thus be disposed in a parallel position proximal to the edge (25).
In view of the above, it can be understood how, in said plate (1B), the housing profile (20) suitable for accommodating a stiffening profile (10) actually consists of the longitudinal space (or longitudinal seat) comprised between said edge (25) and said plate (25b), on the back of said curved edge (25a).
As shown in Fig. 4A, the insertion of the top section of the edge (15) of the stiffening profile (10) in said longitudinal seat of the housing profile (20) is preferably stabilized by means of a transverse set of through screws (V2).
With reference to Fig. 5, the fourth embodiment of the sheet metal (1C) which is not part of the invention is disclosed. The sheet metal (1C) is provided with a stiffening profile (10) that exactly corresponds to the one adopted in the third embodiment of the sheet metal, it being likewise formed by an edge (15) that projects perpendicularly from the first lateral edge of the sheet metal (1C).
The peculiarity of such an embodiment of the sheet metal according to the invention (1C) consists in the configuration of the housing profile (20).
Such a housing profile (20) comprises an edge (26) that projects perpendicularly from the second lateral edge of the sheet metal (1C) and is connected at the end with a border (26a) that projects towards the exterior of the sheet metal (1C).
The function of such a projecting border (26a) is that of connecting said edge (26) with a plate (26b) suitable for being disposed in parallel position relative to the edge (26) and provided with a lower height.
Therefore, in such a fourth embodiment of the corrugated sheet metal which is not part of the invention (1C), the housing profile (20) of a corresponding stiffening profile (10) actually consists in the longitudinal seat comprised between said plate (26b) and said projecting border (26a), downstream said vertex (26b) of said projecting border (26a).
It should be also considered that said projecting border (26a) is provided with a set of holes (preferably made during the laying of the sheet metal) wherein respective fixing screws (V3) are inserted and engaged on the concrete surface covered with the corrugated sheet metal (1C).
Fig. 5A shows the solution adopted to stabilize the coupling between the housing profile (20) of a first sheet of corrugated sheet metal (1C) and the respective stiffening profile (10) of a second adjacent sheet of corrugated sheet metal (1C).
Such a solution provides for the installation of a bolt (31) with an omega-shape and in any case suitable for being exactly superimposed to said housing profile (20) of a sheet of corrugated sheet metal (1C) disposed in the front that already contains the top section of the respective stiffening profile (10).
In such a case, the fixing of such a bolt (31) is obtained by means of said screws (V3), each one of which, before being inserted in one of the holes provided on said projecting border (26a), is inserted through a corresponding hole made in the center of the flat wall of the bolt (31).
Finally, Figs. 6 and 6A show the fifth embodiment of the corrugated sheet which is not part of the invention (1D).
In this last embodiment, the stiffening profile (10) obtained in correspondence of the first lateral edge of said sheet metal (1D), comprises:

a first inclined wing (16), projecting from said flat surface (SP) of said sheet metal (1D)
a flat wall (16a) supported at the end of said inclined wing (16) in parallel position relative to said flat surface (SP) of the sheet metal (1); it being provided that an equidistant set of through holes is obtained on said flat wall (16a)
a second inclined wing (16b) that is connected to said flat wall (16a), facing the opposite side with respect to the one occupied by said first inclined wing (16), and is provided with a lower height
a tubular profile (16c) of substantially square section, which is exactly associated with the rear face of said projecting wall (16a); it being provided that the flat rear surface (16c') of said tubular profile (16c), which is suitably provided with a longitudinal notch (IL), is flush with the flat surface (SP) of the sheet metal (1D).

On the other hand, the housing profile (20), which is obtained in correspondence of the second lateral edge of said sheet metal (1D), comprises:

a first inclined wing (26) that projects from said flat surface (SP) of said sheet metal (1D) with a height and an inclination equal to those of the first inclined wing (16) of said stiffening profile (10), but facing the opposite side
a flat wall (16a) supported at the end of said first inclined wing (26) in parallel position to said flat surface (SP) of the sheet metal (1) and at a height that substantially corresponds to the one occupied by said flat wall (16a) of said stiffening profile (10)
a second inclined wing (26b) that projects from the opposite side of said flat wall (16a) with a corresponding opposite inclination to that one of said first inclined wing (26), said second inclined wing (26b) having a lower height than the first inclined wing (26).

Also in such a case, the function of the housing profile (20) is to be exactly superimposed to said stiffening profile (10) of an adjacent sheet of corrugated sheet metal (1D).
The coupling is obtained by means of a set of screws (V4) suitable for being successively inserted in:

respective holes made in correspondence of the flat wall (16a) of the housing profile (26)
respective holes made in correspondence of the flat wall (16a) of the stiffening profile (10).

Finally, said screws (V4) are intended to grip the concrete surface on which the sheet metal (1D) is to be mounted, after passing through said longitudinal notch (IL) provided in the tubular profile (16c).
Also in such a case, the coupling between the housing profile (20) of a first sheet of corrugated sheet metal (1D) and the stiffening profile (10) of a second sheet of the sheet metal is stabilized by means of a substantially omega-shaped bolt (32).
Said bolt (32) is suitable for being exactly superimposed to said housing profile (20) of a sheet of corrugated sheet metal (1D) already positioned against the stiffening profile (10) of a sheet of corrugated sheet metal (1D).
In such a condition, said bolt (32) is fixed by means of said screws (V4), each one of them being firstly inserted into respective holes made in the flat wall of the bolt (32).

Claims

Corrugated sheet metal provided with a flat surface (SP) comprised between two lateral edges, and one or more projecting frets (G), wherein
the first lateral edge consists of a box-shaped stiffening profile (10) with a high compressive strength that projects with respect to said flat surface (SP), in parallel position on the same side from which said frets (G) protrude;

the second lateral edge consists of a housing profile (20) with suitable shape and dimensions so as to exactly accommodate said stiffening profile (10) of an adjacent identical sheet of corrugated sheet metal; wherein

said stiffening profile (10) comprises:
- an inclined wing (11) projecting from said flat surface (SP) of said sheet metal, and

- a flat wall (12) supported at the end of said inclined wing (11) in parallel position to said flat surface (SP) of said sheet metal,

said housing profile (20) comprises:
- a first inclined wing (21) projecting from said flat surface (SP) of said sheet metal, and

- a flat wall (22) supported at the end of said first inclined wing (21) in a parallel position to said flat surface (SP) of said sheet metal and at a height that corresponds exactly to the one occupied by said flat wall (12) of said stiffening profile (10),

characterized in that

said stiffening profile (10) comprises a U-shaped profile (13) with substantially square section that extends from the inner side of said flat wall (12) and is provided with a height such that its rear end (13a) is flush with said flat surface (SP) of said sheet metal (1);

said first inclined wing (21) of the housing profile (20) has a height and inclination equal to those of said inclined wing (11) of said stiffening profile (10), but facing the opposite side;

said housing profile (20) comprises a second inclined wing (23) that projects from the opposite side of said flat wall (22) with a corresponding opposite inclination to that one of said first inclined wing (21), with respect to which it has a lower height.
The corrugated sheet metal of claim 1, wherein said sheet metal is provided with a fixing bolt (30, 31, 32) suitable for being exactly superimposed to said housing profile (20), after the latter has been coupled with the corresponding stiffening profile (10) of an adjacent sheet of said corrugated sheet metal; wherein said bolt (30, 31, 32) is provided with holes for the insertion of screws (V1, V2, V3, V4) aimed at stabilizing said coupling.
Corrugated sheet metal provided with a flat surface (SP) comprised between two lateral edges, and one or more projecting frets (G), wherein
the first lateral edge consists of a box-shaped stiffening profile (10) with a high compressive strength that projects with respect to said flat surface (SP), in parallel position on the same side from which said frets (G) protrude;

the second lateral edge consists of a housing profile (20) with suitable shape and dimensions so as to exactly accommodate said stiffening profile (10) of an adjacent identical sheet of corrugated sheet metal;

said stiffening profile (10) comprises:
- an inclined wing (11) projecting from said flat surface (SP) of said sheet metal, and

- a flat wall (12) supported at the end of said inclined wing (11) in parallel position to said flat surface (SP) of said sheet metal;

said housing profile (20) comprises:
- a first inclined wing (21) projecting from said flat surface (SP) of said sheet metal, and

- a flat wall (22) supported at the end of said first inclined wing (21) in parallel position to said flat surface (SP) of said sheet metal and at a height that corresponds exactly to the one occupied by said flat wall (12) of the stiffening profile (10);

characterized in that

said stiffening profile (10) comprises a U-shaped profile (14) with right trapezoidal section that extends from the inner side of said flat wall (12) and is provided with a height such that its rear end (14a) is flush with said flat surface (SP) of said sheet metal (1);

said first inclined wing (21) of the housing profile (20) has a height and inclination equal to those of said inclined wing (11) of said stiffening profile (10), but facing the opposite side;

said housing profile (20) comprises a second inclined wing (23) that projects from the opposite side of said flat wall (22) with a corresponding opposite inclination to that one of said first inclined wing (21), with respect to which it has a lower height.
The corrugated sheet metal of claim 3, wherein said sheet metal is provided with a fixing bolt (30, 31, 32) suitable for being exactly superimposed to said housing profile (20), after the latter has been coupled with the corresponding stiffening profile (10) of an adjacent sheet of said corrugated sheet metal; wherein said bolt (30, 31, 32) is provided with holes for the insertion of screws (V1, V2, V3, V4) aimed at stabilizing said coupling.