Description

Field of the art

The present invention operates in the field of production of sound-insulating and/or soundabsorbing elements, specifically a structure for noise abatement, comprising semiprefabricated modules made of reinforced concrete supporting a sound-reflecting and/or sound-absorbing paneling. Still more specifically, the object of the present invention regards semi-prefabricated modules made of durable reinforced concrete, resistant to seismic events and fireproof Typically, but not exclusively, the present invention regards acoustic mitigation works along railway sections.

Prior art

Today, there are numerous systems and means used for absorbing and attenuating noise- but these are almost always applied in closed areas, i.e. in that which can be considered a home/residential setting.

Especially in recent years, research has been pushing towards solutions that increasing serve towards limiting the noise pollution produced by worksites, road and railway sections, which presently afflicts both urban and extra-urban settings.

One example is the product that is the object of the patent application CN102094395A. This claims a sound-absorbing panel for concrete acoustic barriers, characterized in that it comprises a sound-insulating layer, an interspace layer and a sound-absorbing layer; the acoustic insulation layer is a shaped frame with depressions and the acoustic absorption layer is arranged on the insulation layer. On the surface of the frame of the acoustic layer, a cavity layer is present between the acoustic absorption layer and the acoustic insulation layer; the acoustic absorption layer also has a circular hole that amplifies the absorbing effect.

Nevertheless, acoustic barriers are limited in some fields, indeed they are mainly used for acoustic insulation and noise reduction in transportation and in structures such as highways, elevated composite roads, light urban rails and railways.

Another patent is ES2046931A2. This further document refers to a panel in sound-absorbing cement conglomerate and to a process for the manufacturing thereof, whose fundamental characteristic is that of having, at least on one surface thereof, openings towards the outside of its surface, communicating inside with resonance chambers, in a manner such to direct that surface towards a propagation front of the acoustic waves. In this manner, one obtains an acoustic absorption or attenuation in the field of frequencies of that acoustic wave propagation noise source. The panel can have greater or smaller width and form modules that can be arranged alongside others so as to form a barrier or even a prefabricated platform; this can even act as a railway base on which rails will be logically arranged. Such panel has an assembly that is complex and involves considerable time and money: first of all, a rectangular formwork is arranged, with two molds at the interior, subsequently, a concrete casting is executed on one of the boxes or molds so as to obtain a first sheet, which will be provided with a series of interspaces generated with metal elements that will be subsequently removed; then, one of the ends of a series of metal elements is immersed in said concrete casting, which will come to determine the means for connecting with another; the aforesaid metal filling elements are then removed, subsequently filling the cavities with porous soundabsorbing material, such as expanded clay. The concrete is poured into the second form or mold, obtaining a second sheet, finally, the first mold is overturned onto the second, carrying out the superimposition of both sheets and the penetration of the fresh concrete of the metal joint elements, with the particular feature that in the latter step the holes of the second sheet are positioned at the cavities existing in the first.

The object of the present patent application is to provide an inexpensive, highly strong solution that is adapted to solve the problems of noise pollution caused by urban and extra- urban railway sections.. The object of the present document offers an assemblable and modulatable product, forming a protective barrier capable of being adapted to the different work site types, providing an extremely strong/resistant instrument. Description of the invention

According to the present invention, an innovative acoustic mitigation structure is provided, mainly for the railway field, and comprising semi-prefabricated modules made of reinforced concrete in turn supporting support uprights an a possible sound-reflecting and/or soundabsorbing paneling.

An essential component of the invention is the semi-prefabricated element, made of reinforced concrete. This is fireproof and extremely resistant to deterioration. The upper part of the same is tilted with respect to the underlying, with a tilt up to 12°; such tilt also allows advantageously developing an acoustic action, since it reflects the sound wave towards the ballast of the railway over- structure where the same is refracted. Such element can however also be vertical and/or with different tilts.

With regard to the acting forces and to the strength of the semi-prefabricated element itself, this is not only able to sustain gravitational loads, i.e. permanent actions such as the action of the weight thereof, the action of the weight of the overlying upright with the relative paneling, but also the horizontal loads, i.e. variable actions, such as that of the wind, of storms and of the aerodynamic action of the moving railway convoys.

Advantageously the semi-prefabricated element is composed of an internal face and an external face, joined by rebar rods for reinforcement structures, which allow containing concrete castings, adapted to fix and maintain firm the entire structure and to ensure the necessary stress resistance performances.

The acoustic mitigation structure also assumes the creation of a foundation structure against which the aforesaid semi-prefabricated element is abutted.

Such foundation structure requires or can require perforations, drilling, excavations, casting on any surface, for the installation of waiting reinforcement structures in order to become integral with the semi-prefabricated element.

Indeed such base is preferably shaped at the top in such a way as to have a hollow housing for the engagement of the lower part of the semi-prefabricated element.

The upper part of the acoustic mitigation structure comprises the abovementioned support upright, which is engaged, by means of plate and log bolts or by means of casting or other fixing systems, to the upper end of the semi-prefabricated element. Such support upright, supporting if necessary the tilt of the upper part, performs the function of supporting soundinsulating and/or sound-absorbing panels. The upright is preferably made of steel, fiberglass or concrete.

The acoustic mitigation structure can generally and advantageously reach a height up to 10m with respect to the abutment plane of the prefabricated element, being adapted to the mitigation needs both in urban and extra-urban settings, providing an optimal acoustic result. The possible panels overlying the semi -prefabricated element are of sound-reflecting (e.g. glass or polymethylmethacrylate) type or sound-absorbing (e.g. steel, aluminum, fiberglass, concrete, mineralized wood, clay) type.

The sound-absorbing materials inside/outside the panels can be of three types:

- mineral, such as glass or rock wool and the fibers of mineralized wood; all porous materials that have the capacity of converting the acoustic energy into heat;

- plant, such as cork, expanded clay or wood; synthetic, i.e. chemical products such as expanded polyurethane, polyesters that have good capacities for eliminating noise.

The sound-absorbing qualities of such panels are further improved since they can be suitably shaped with a visible face with grooves, preferably meandering or “U” shaped. Such grooves can be advantageously horizontal or vertical, being adapted based on the request.

In one of the preferred embodiments, the external face of the semi-prefabricated element can be shaped with grooves, prints, fretted matrices for an improved aesthetic effect. The possibility of applying sound-absorbing materials in the internal part, considerably increases the sound-absorbing qualities of the entire acoustic mitigation structure. The structure according to the present invention is advantageously assemblable and modulatable in sequence, so as to form a protective barrier suitable for different types of worksites.

In one of the preferred embodiments, the invention can advantageously comprise an alarm system, installed on the internal surface of the semi-prefabricated element, powered by batteries and connected to a remote station. Such system can be used in case of danger, alerting said remote station, which can readily provide aid to the requesting party.

The installation of multiple acoustic mitigation structures leads to the creation of a noise barrier, usable for example as a barrier for railway sections. The attainment of each single structure provides for a series of operations: the ground is prepared, on which the structure will be installed for the installation of suitably-sized waiting reinforcement structures, adapted to receive concrete castings constituting part of the foundation system, also having considered that in one of the preferred embodiments, the foundation part can also be prefabricated or semi-prefabricated; subsequently there is the shaping of the upper part of said base, such that it can receive the engagement of the lower part, of the semi-prefabricated element; once the semi-prefabricated element is positioned on the base, concrete castings are made at its interior, in a manner such to ensure the blocking and confer the suitable static and strength qualities thereto; the concrete cast in situ allows blocking suitable log bolts and/or other systems/methods for fixing a support upright of the panels, finally, the work is completed with the installation, within the assembled structures, of paneling that is soundreflecting and/or sound-absorbing.

Advantageously the method can comprise a step for reinforcement by connecting the bases of multiple side-by-side acoustic mitigation structures, through the fixing of a steel bar on the surface of the bases.

In addition, preferably on the surface of the semi-prefabricated element and on the panels, decorative elements can be applied such as painting, coating and/or advertising media.

The safety factors of the present invention are further improved through the mounting of supports on the internal face of the semi -prefabricated element, such as for example shelves, hooks, safety material and/or panels, adapted to optimize the spaces provided by the worksite and its safety in case of emergency.

Finally, the method can comprise a step of strengthening the positioning of the lower part of the semi-prefabricated element in the shaping made in the base through in-situ seals: these are advantageously engaged in the resulting spaces between the shaping of said base and said lower part; they prevent the spacing of the internal face and of the external face when concrete castings are introduced within said semi-prefabricated element.

The advantages offered by the present invention are evident in light of the description set forth up to now and will be even clearer due to the enclosed figures and to the relative detailed description.

Description of the figures

The invention will be described hereinbelow in at least a preferred embodiment as a nonlimiting example, with the aid of the enclosed figures, in which:

- FIGURE 1 shows a perspective view of a semi -prefabricated element 10 according to one embodiment of the present patent application,

- FIGURE 2 illustrates a section of several components, during mounting, of an acoustic mitigation structure 100 according to one embodiment of the present patent application;

- FIGURE 3 shows a section view ⁷ of an acoustic mitigation structure 100 according to one embodiment of the present patent application.

Detailed description of the invention

The present invention will now be illustrated only as a non-limiting or non-binding, with reference to the figures which illustrate several embodiments relative to the present inventive concept.

With reference to FIGS. 1, 2 and 3, the components of an acoustic mitigation structure 100 according to the present invention are shown, such structure adapted to solve the problems of noise pollution of infrastructures in urban and extra-urban areas, such as railway sections 200, being installable on any surface 300, with components highly resistant to natural wear and/or ad seismic events. In particular, FIG. 1 shows the components of a semi -prefabricated element 10 according to the present invention; FIG. 2 shows the step of insertion of said semi-prefabricated element 10, in the shaping of the base 30 of the foundation structure, when the latter has already been engaged on a surface 300; FIG. 3 illustrates all the components of an acoustic mitigation structure 100, when this is installed on a surface 300 and the internal face 13 of said semi -prefabricated element 10 is directed towards a railway line 200.

The invention comprises the creation of a foundation structure, comprising a multiplicity of micropiles 31 and a base 30 made of reinforced concrete that is cast in situ, adapted to be buried on a surface 300, by means of previous excavation, in such a way as to support and hold the weight of all the components of said acoustic mitigation structure 100. In particular, said base 30, once consolidated, is shaped at the top in such a way as to have a hollow housing for the engagement of a semi-prefabricated element 10. In FIG. 3, in-situ seals 21 are also present which are engaged in the resulting spaces between the shaping of said base 30 and said lower part 11. In this manner, said in-situ seals 21 prevent the spacing of the internal face 13 and of the external face 14, during the introduction of the subsequent concrete castings within said semi-prefabricated element 10.

One of the fundamental components is represented by the semi -prefabricated element 10, which is engaged in the upper part of said base 30, so as to form a strong and durable loadbearing module for supporting a support upright 16 made of steel, fiberglass, concrete or other material. In particular, the semi-prefabricated element 10 is divided into a lower part 1 1 perpendicular to said base 30, in such a way as to allow a correct discharge of the loading force, and an upper part. 12, tilted with respect to said lower part. 1 1 towards the railway section 200, in such a way as to increase the protective and sound-absorbing capacities of said acoustic mitigation structure 100. Said semi-prefabricated element 10 also consists of an internal face 13 and an external face 14, joined by rebar rods for reinforcement structures 15, adapted to contain concrete castings 20, which confer solidity to said semi -prefabricated element 10.

The upper part of the entire acoustic mitigation structure 100 is represented by a support upright 16, engaged by means of joint with plate and log bolts 19, or cast or fixed with accessories, at an internal base made reinforced concrete to the upper end of said upper part 12. The upright has the function of supporting and retaining acoustic light paneling 18 that are sound-insulating and/or sound-absorbing. The main characteristic is that said steel upright 16 supports the tilt of said upper part.

Specifically the internal face of said light panel 18, i.e. that directed towards the railway line 200, in the sound-absorbing version, is constituted by a metal, plastic or fiberglass shell containing sound-absorbing materials which improve the sound-absorbing qualities of the acoustic mitigation structure 100.

On the internal part, of the semi-prefabricated element, sound-absorbing materials can be integrated such as fibers of mineralized wood, expanded clay, synthetic material, etc., all porous materials that have the capacity to convert, the acoustic energy into heat. Finally, it is clear that modifications, additions or variations that are obvious for the man skilled in the art can be made to the invention, without departing from the protective scope that is provided by the enclosed claims.