DESCRIPTION

SCOPE OF APPLICATION

The present invention relates to a containment sheet and a containment structure comprising said containment sheet.

In particular, the present invention relates a sheet and a containment structure employable in the field of construction, civil, environmental, hydraulic, geotechnical and mining engineering, and more generally for all those applications in which it is required to effectively contain a mass (for example a soil) or an existing structure to avoid subsidences and overrunning or those applications in which it is necessary to provide a safety structure, either provisional or permanent, against the fall of things or people.

PRIOR ART

To cope with the problem of falling boulders or for the containment of any debris flows, slides and avalanches, containment structures are usually installed which consists of steel barriers in the form of nets, characterized by a more or less narrow mesh depending on the morphology of the surrounding soil. Any boulders in free fall or soil/snow flow will therefore impact against the nets, which have the function of containing them, operating a dynamic confinement, to avoid dispersions and damages to people or things.

These containment nets involve very important scaffolding both economically and structurally.

Another type of containment structure commonly used is the one employed for the recovery and rehabilitation of existing buildings. In this case, the metal nets are wrapped around the perimeter walls, the pillars or the columns to reinforce them by operating a static confinement of the existing structure. In addition to being very expensive, heavy and logistically complicated to transport and install, metal nets are also subject to the phenomenon of corrosion, therefore a long exposure to atmospheric agents could negatively affect the durability and reliability of the system.

Another example of a containment structure, commonly used in marine, coastal, fluvial, or lake environments is defined by a net of concrete blocks connected to each other by flexible cables that are immersed and to contain certain seabeds or escarpments or to protect specific pipelines by surmounting them and thus preventing the accidental crushing thereof. It is evident that these systems are bulky, heavy, expensive and difficult to implement and also subject to aggressive phenomena of corrosion due to the marine or brackish environment.

SUMMARY OF THE INVENTION

In this context, the technical task underlying the present invention is to propose a containment sheet and a containment structure that overcome one or more of the drawbacks of the above-mentioned prior art, realizing an economical, reliable and long-lasting solution.

In particular, an object of the present invention is to make available a lightweight, efficient and high performance containment sheet.

A further object of the present invention is to make available a containment sheet that is modular and versatile in the applications.

Still, an object of the present invention is to make available a containment structure which is structurally simple and which can be easily constructed, transported and implemented.

The technical task set and the objects specified are substantially attained by a sheet and a containment structure comprising the technical features as set out in one or more of the appended claims.

In particular, the present invention provides a containment sheet comprising a flexible weave defined by a plurality of reinforcement strips advantageously interwoven with each other in a warp and weft pattern. In other words, the reinforcement strips are simply interwoven with each other perpendicularly, but are not engaged by any mechanical means or by welding points or lines; therefore, reciprocal slides of varying intensity depending on the space left between the weft strips and between the warp strips are allowed between the reinforcement strips, that is, depending on the so-called “gap” or “open surface” of the weave. These reciprocal slides also promote punching resistance as well as containment in the dynamic phase.

In particular each reinforcement strip comprises:

- a polymeric coating capsule surrounding a plurality of longitudinal channels extending parallel to a longitudinal extension direction of the reinforcement strip and arranged as aligned in a direction perpendicular to the longitudinal extension direction, and

- a plurality of longitudinal reinforcement fibres arranged within the longitudinal channels.

In other words, each reinforcement strip has a sequence of adjacent longitudinal channels filled with longitudinal reinforcement fibres and embedded in a polymeric matrix.

Advantageously, the presence of longitudinal reinforcement fibres gives the reinforcement strip the strength characteristics required for the static and/or dynamic containment function it must perform.

The reinforcement strip to which reference is made herein is therefore a strip-shaped composite product (also referred to as a “strap” or “tape” or “geostrip”) typically obtained by co-extrusion of a coating capsule containing a core of fibres, i.e. yarns, filaments, threads or inserts with tensile strength properties, for various structural reinforcing or stabilizing applications.

By using high-tenacity threads, yarns and fibres, it is in fact possible to obtain reinforcement strips that offer the necessary support and strengths to loads and greater durability than ordinary structural construction methods and materials such as steel and concrete. Furthermore, the containment structure comprises at least one connecting portion connected to the flexible weave and suitable for connecting the containment sheet to a further containment sheet, for realizing a larger modular containment structure, and/or to an external structure, for effectively engaging to it.

The containment sheet subject-matter of the present invention, thanks to the presence of the flexible weave, can therefore be designed to be subjected to high-intensity dynamic and static loads. The composite material of the reinforcement strip (polymeric matrix + longitudinal fibres) offers characteristics of high strength and at the same time flexibility, also ensuring an effective resistance to dynamic punching and also to the impact.

The containment sheet thus defined effectively adapts both in the applications where it is expected to have strong accidental and impulsive dynamic stresses, and in the applications of static confinement of existing structures.

The presence of a flexible weave made of composite material with polymeric coating capsule advantageously guarantees an excellent adaptability in the most varied conditions of use, preventing in particular the occurrence of the corrosive phenomenon.

The containment sheet subject-matter of the invention is light compared to known steel solutions and is easy to transport (it can be wound up or transported in layers), simple to produce (for example by co-extrusion process), versatile in the applications (it can also be used in water), and easily customizable (both in terms of size and strength characteristics) according to the design needs.

The interweaving of reinforcement strips that incorporate a plurality of longitudinal fibres having tensile strength characteristics makes it possible to realize an efficient weave capable of containing/retaining/confining a mass in a static position (for example the walls of a building) or containing/retaining a possible mass in motion (for example boulders in free fall from an escarpment or debris flow).

The present invention also relates to a containment structure comprising at least two containment sheets in accordance with the present invention placed side by side and connecting means configured to connect said at least two containment sheets at least at said connecting portions.

In other words, the containment structure provides a modular system of containment sheets that can be easily joined to define solutions of larger dimensions than a single containment sheet. The connection at the peripheral connecting portions ensures a quick implementation.

The dependent claims herein incorporated for reference, correspond to different embodiments of the invention.

Further characteristics and advantages of the present invention will appear more clearly from the indicative, and therefore non-limiting, description of a preferred but not exclusive embodiment of a containment sheet and containment structure, as illustrated in the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a schematic section of the flexible weave of a containment sheet in accordance with the present invention.

Figure 1A is a schematic section of a possible embodiment of a containment structure according to the present invention, comprising a sheet according to the present invention and two layers coupled to the flexible weave.

Figures 2-6 schematically show some embodiments of a containment structure in accordance with a first embodiment of the containment sheet according to the present invention, wherein different details of connection between two or more containment sheets are illustrated.

Figures 7-8 schematically show two embodiments of a containment structure in accordance with a second embodiment of the containment sheet according to the present invention. Figures 9 and 10 schematically show two examples of connection by means of connecting elements insertable at least partially within respective flexible weaves of the containment sheets according to the present invention, straddling adjacent reinforcement strips.

Figure 11 schematically shows an exemplary embodiment of a boxshaped containment structure in accordance with the present invention.

DETAILED DESCRIPTION

With reference to the accompanying figures, a containment sheet has been denoted overall with 1 , while a containment structure has been denoted overall with 100.

The sheet 1 comprises a flexible weave 2 defined by a plurality of reinforcement strips 3 interwoven with each other in a warp and weft pattern.

By the term “strip” is meant a substantially flat tape-like element having a length (measured along a longitudinal extension direction of the strip 3) greater than the width L of the strip 3, and having a thickness S (measured perpendicularly to the longitudinal extension direction and to the width L) much smaller than the width L of the strip 3.

The strip 3 has two opposite side edges 3a with respect to the longitudinal extension direction and two opposite terminal ends 3b (so-called “head” and “tail” ends of the strip). In other words the length of the strip 3 is measurable between the opposite ends 3b, while the width L is measurable between the side edges 3a.

Preferably the reinforcement strips 3 have width L between 10 mm and 200 mm, even more preferably equal to 50 mm, and thickness S between 0.1 mm and 50 mm, even more preferably equal to 2 mm.

Each strip 3 comprises:

- a polymeric coating capsule 4 surrounding a plurality of longitudinal channels 5 extending parallel to the longitudinal extension direction of the strip 3 and arranged as aligned in a direction perpendicular to the longitudinal extension direction, and

- a plurality of longitudinal reinforcement fibres 6 arranged within the longitudinal channels 5.

In other words the longitudinal channels 5 are arranged adjacent and parallel in sequence between the opposite side ends 3a within the strip 3 and extend for the entire length of the strip 3.

In particular, “plurality of longitudinal reinforcement fibres” 6 means a yarn or a filament made from a plurality of fibres, threads, filaments or inserts with tensile strength characteristics juxtaposed between them longitudinally to define a longitudinally extending reinforcement element.

Preferably the plurality of longitudinal reinforcement fibres 6 are high tenacity yarns, preferably high tenacity synthetic yarns, such as polyester fibres or aramid fibres, while the polymeric coating capsule 4 is preferably made of polyethylene.

It should therefore be noted that the term “longitudinal” is intended to indicate that the plurality of fibres 6 defines a yarn extending in a direction parallel to the longitudinal extension direction X of the strip 3.

Preferably the longitudinal channels 5 have a width, measured perpendicular with respect to the longitudinal extension direction of the reinforcement strip 3 and parallel to the width L of the reinforcement strip 3, of between 0.5 mm and 200 mm.

Preferably the longitudinal channels 5 have a thickness, measured perpendicular with respect to the longitudinal extension direction of the reinforcement strip 3 and parallel to the thickness S of the reinforcement strip 3, of between 0.1 mm and 50 mm.

Preferably the distance between adjacent longitudinal channels 5 is less than the width of the longitudinal channels 5.

Preferably the reinforcement strips 3 have tensile strength between 1 kN/m and 1000 kN/m, even more preferably equal to 50 kN/m.

The containment sheet 1 according to the present invention further advantageously comprises at least one connecting portion 7 connected to the flexible weave 2 and suitable for connecting the containment sheet 1 to a further containment sheet 1 and/or to an external structure E.

According to a further aspect of the present invention there is provided a containment structure 100 comprising at least two containment sheets 1 according to the present invention placed side by side and connecting means configured to connect said at least two containment sheets 1 at least at said connecting portions 7.

In accordance with a first embodiment, illustrated in Figures 2-6, preferably the connecting portion 7 is defined by a peripheral joint strip 8, preferably continuous, obtained by welding (for example ultrasounds) free opposite terminal ends 3b of the reinforcement strips 3.

In other words, once the weave 2 is made by interweaving the strips 3, the head ends of the strips 3 are welded together and the tail ends of the strips 3 are welded together 3 so as to define a peripheral selvedge cord (i.e. the peripheral joint strip 8) at which it is possible to make the connection of the sheet 1 with another sheet 1 or fix it to an external structure E, for example the existing structure to be contained.

As illustrated in Figures 2-6, preferably the connecting portions 7 of the sheets 1 are at least partially overlapping with each other at overlapping areas, and the connecting means comprise fasteners 101 engageable to the containment sheets 1 at such overlapping areas to connect them.

Some examples of fasteners 101 may be: nails, screws, bolts, rivets, cables, laces, strings, staples.

With particular reference to Figure 2, preferably the peripheral joint strip 8 also has a plurality of connecting holes 9 to facilitate the connection with the fasteners 101. For example, the connecting holes 9 are reinforced to avoid any tears during use.

Preferably the diameter of the connecting holes 9 is between 5 mm and 20 mm and preferably the connecting holes 9 are arranged at a minimum spacing of 50 mm, preferably 100 mm.

In particular, Figure 2 illustrates two sheets 1 overlapped at an edge of the respective peripheral joint strips 8 along which there are arranged connecting holes 9 inside which a string 101 is alternately inserted to connect the two sheets 1 .

As illustrated in Figure 3, the sheet 1 may also preferably comprise at least one stiff joint bar 10 overlapping or overlapped to the peripheral joint strip 8 and engageable by the fasteners 101 .

The containment structure 100 illustrated in Figure 3, shows how the stiff joint bar 10 can be arranged both above and below (in dash) the overlapping area of the peripheral joint strips 8. For example, in this case the joint element 101 can be a nail, a bolt or a screw, which crosses both the stiff joint bar 10 and the two overlapped peripheral joint strips 8, which then also preferably fits into an external structure E (embodiment not illustrated).

Preferably the stiff joint bar 10 can be made of steel, wood, fibreglass or plastic material.

Figures 4-6 schematically illustrate three examples of connection at the overlapping area between two sheets 1 .

In particular in Figure 4 the fastener 101 is a nail, or a screw, which passes through the two peripheral joint strips 8 of the respective sheets 1 and is fixed on an external structure E made of wood. Note that the external structure E can also be made of another material, for example it can be a concrete plinth or a steel pole.

In Figure 5 the fastener 101 is defined by a staple (or stapling) that passes through the two peripheral joint strips 8 of the respective sheets 1 and is then fixed on an external structure E made of wood.

In Figure 6 the fastener 101 is defined by a bolt that joins by means of a screw and nut two stiffening bars 10 and two peripheral joint strips 8.

In accordance with a second embodiment, illustrated in Figures 7 and 8, preferably the connecting portion 7 is defined by free terminal ends 3b of the reinforcement strips 3 folded, preferably around a folding direction perpendicular to the longitudinal extension direction of the reinforcement strips 3, and fixed, preferably by hot or ultrasonic welding, to the reinforcement strips 3 themselves to form connecting through cavities 11 .

Preferably therefore the connecting means of the containment structure 100 comprise connecting elements 102 insertable at least partially within the respective connecting through cavities 11 to connect together at least two containment sheets 1 .

In other words, the connecting through cavities 11 are obtained simply by folding the terminal ends 3b of the strips 3 and fixing them in a rearward position to form rings/loops/eyelets for the insertion of the connecting elements 102, such as bars, ropes, strings or cables.

An example of sheet 1 in accordance with the present invention is illustrated in Figure 7 in which the connecting portion 7 is defined by four rows of connecting through cavities 11 inside two of which bars 102 are inserted for connection to an external structure (not illustrated) while the remaining two rows of connecting through cavities 11 can be connected to other sheets 1 as illustrated in Figure 8.

The implementation of the structure 100 is therefore very simple and quick; in fact it is sufficient, for example, to unwind a sheet 1 and insert the through cavities thereof in the bars 102 to connect it to the external structure, or to place a row of connecting through cavities 11 side by side to a row of connecting cavities 11 of another sheet 1 and insert another bar 102.

In particular, the embodiment with connecting portion 7 defined by the connecting through cavities 11 allows to realize a dynamic weave 2 that can easily adapt to the stresses to which it will possibly be subjected. In fact, the weft and warp interweaving with spaced variable meshes allows reciprocal sliding between adjacent strips so as to adapt to the structure to be contained (for example in the confinement applications) or to absorb/cushion any impact-impulsive stresses (for example in the applications for falling boulders).

Preferably the distance between two consecutive weft reinforcement strips 3 or two consecutive warp reinforcement strips 3 is between 0.1 mm and 200 mm, preferably equal to 5 mm.

In other words, the interweaving of the strips 3 is variable, so the gap of the mesh (i.e. the distance between two warp and weft strips) is variable. The mesh of the weave 2 can therefore be made more or less thick based on the application and the required containment function.

Therefore advantageously the open surface (which describes the percentage of free area on the entire surface of the canvas) is variable depending on the type of application required.

The sheet 1 according to the present invention may further advantageously comprise at least one layer 2a coupled at least partially to the flexible weave 2, such as a natural fibre geomat or a geotextile, typically in polyethylene.

Advantageously it is therefore possible to overlap several layers at least at the flexible weave 2.

The coupling of the weave 2 with a layer 2a made of specific material therefore allows to realize very versatile containment solutions.

With particular reference to Figure 1A, preferably moreover the sheet 1 may comprise a waterproof membrane 2b interposed between the layer and the flexible weave 2.

Advantageously, therefore, it is possible to give the sheet 1 waterproof characteristics for certain applications.

With reference to Figures 9 and 10, the connecting means may further comprise connecting elements 102 insertable at least partially within the respective flexible weaves 2 straddling adjacent reinforcement strips 3.

In other words, it is possible to connect two or more sheets 1 to each other simply by passing bars 102 between alternating spaces defined between consecutive adjacent strips of the weave 2 and then connecting them to each other (for example by means of ties 103), as illustrated in Figure 9, or by passing strings 104 between alternating spaces defined between consecutive adjacent strips of the weave 2, as illustrated in Figure 10. Finally, as illustrated in Figure 11 , the containment structure 100 can be made so as to define a three-dimensional box-shaped structure, i.e. able to enclose/confine on several sides an existing structure. For example in Figure 11 the containment sheets 1 are connected (connecting means not illustrated) to each other at corners of an ideal parallelepiped.

The present invention thus makes available a containment sheet 1 and containment structure 100 that are highly performing and versatile in design and use.

The characteristics of the sheet 1 subject-matter of the invention lend themselves to numerous and specialized applications, in particular of a geotechnical, structural, road, but also fluvial, and coastal type and for erosion control.

Typical applications can for example be found on marshy areas or in lake/marine areas, consolidation of cliffs or areas at sea, riverbank antierosion and protection systems, access roads and loading platforms, containment barriers for rockfalls and avalanches, barriers for the protection and containment of people and/or things.

The sheet 1 is prefabricated and can be easily transported to the installation site to be quickly implemented.

The sheet 1 can be wound into a roller, then easily stowed and moved. The sheet 1 can then be unwound using a winch or other mechanical means. For coastal or fluvial applications the roll can be carried on a barge and drawn by it at sea; or for applications for the protection of people and/or things from impacts due to things, boulders or snow, the panel can be unwound through upper cables as if it were a tent.

For the consolidation of cliffs or marine lake areas, or for the construction of piers, the sheet 1 can be sized to guarantee the mechanical strength necessary to resist, for example, the dynamic stresses of the cyclopean boulders during their launching operations. The operations of laying the filling material (usually consisting of large-sized boulders) consist in fact of its unloading directly from trucks or from struts on the sandy-slime seabed. The function of the sheet 1 in this application is therefore to protect the seabed and contain the cliff and the freshly unloaded carryover soil.

These are just some examples of the multiple possibilities of use of the sheet 1 and of the containment structure 100 obtainable with the sheet 1 subject-matter of the present invention; the present invention therefore achieves the proposed purposes, overcoming the drawbacks complained of in the known art.