Patent Description:
The invention relates to a technical solution for improving the resistance to horizontal strain (e.g., seismic type) of existing brick buildings, such as those made of load-bearing bricks, and of reinforced concrete buildings with brick masonry panels, residential or industrial buildings, said improvement being obtained by operating mainly from the outside and with low-impact operations that allow the building to be kept usable during the work. In fact, it is well known that masonry buildings constructed in the past without provisions with respect to seismic actions are highly vulnerable, and that the known traditional techniques have the disadvantage of being highly invasive on the use of the building, while the known techniques considered innovative and non-invasive have the disadvantage of only partially solving the problems of vulnerability of such buildings to external stresses such as those due to seismic or flood or landslides events.

Prior art documents <CIT>; <CIT> and <CIT> refer to a reinforced masonry comprising a wall panel having an accessible face vertical and adjacent to a set of respective horizontal curb elements each one associated with the wall panel. Said reinforced masonry comprises a plurality of rod elements fixed within respective seats carried out in the accessible face of the wall panel. Prior art document <CIT> refers to a reinforcing element.

One object of the present invention is to propose a reinforced masonry in order to improve its resistance to horizontal stresses, particularly those due to seismic events. Another purpose is to propose a reinforced masonry whose architectural and aesthetic characteristics generally do not differ significantly from those of the masonry itself prior to its reinforcement.

Further object is to propose a reinforced masonry whose final strength characteristics can be predetermined and obtained in a way that can be modulated according to needs and contingencies, within an overall seismic improvement project.

Another object is to propose a method for carrying out the reinforcement of the masonry which allow the use of the building even during the implementation of such method.

Further object is to propose a method that can be implemented in pre-existing buildings and masonries made of brick, or other kind of building materials, load-bearing or in buildings and masonries with reinforced concrete structure and with infill made of brick walls, such as hollow or solid bricks.

Other objects are to propose a method by which reinforcements of predeterminable strength can be made as required, in single or multi-storey buildings and in specific portions or in the whole of buildings and masonries.

Another obejct of the present invention is to improve, compared with known techniques, by as much as <NUM>-<NUM> times the resistance to horizontal actions of masonry panels without increasing the thickness of the masonry itself.

Further object is to propose a method that can be implemented in a simple way to carry out the reinforced masonry even by typical workers such as those engaged in construction, moving limited weights that allow intervention with no more than two workers operating on a scaffold. This and other objects are achieved by a masonry according to claim <NUM> and a method according to claim <NUM>.

It is noted that despite the simplicity of installation, the invention allows the reinforced masonry to reach the theoretical limit strength of the panels, which is that corresponding to diagonal compression failure.

The invention also includes specific techniques for anchoring to slab, curbs or building foundations.

The present invention can be the only intervention technique to be used in the case of buildings made entirely of load-bearing masonry, or it can be used to reinforce specific portions of a reinforced concrete building, even in conjunction with other intervention techniques.

In particular, three types of interventions are possible, similar from a technological point of view but very different from a structural point of view:.

Reinforcement can be placed over the entire height of the building, modulating the number of bars for each floor according to the design and using the accessory systems listed below.

The reinforcement can also allow an improvement in the seismic performance of the building by operating only from the outside of the building and/or in the common parts, with obvious advantages from the point of view of reduced invasiveness of the interventions.

The intervention allows to improve the strength and ductility of the panels, as well as to avoid problems of out-of-plane tilting of the panels (both load-bearing and infill), without changing the stiffness of the structure in the case of load-bearing masonry, thus allowing, if necessary, to classify the intervention as "reinforcement intervention or local intervention" under the current Standards.

The characteristics of the invention are highlighted below with particular reference to the accompanying drawings in which:.

With reference to <FIG>, numeral <NUM> indicates the reinforced masonry of the present invention comprising at least one masonry panel M, for example, consisting of a wall or portion of a wall made of solid or hollow bricks or other bricks of a building used for dwelling or industrial purposes or a retaining wall or consisting of an infill wall of a frame structure with reinforced concrete columns and beams, where such wall panel has at least one accessible face F, e.g. and preferably an exterior face of the masonry and an interior face thereof.

Such a face is usually flat and vertical but may be curved or slightly inclined.

The masonry may be without, or comprise one or more, floor curb elements C located at the height of the floors, and/or roofing and/or foundation. For example, the masonry may be without curb elements when it consists of enclosure or retaining walls.

Where present, such curb elements C are nearly horizontal and each is associated with at least one wall panel M that is closed, i.e., solid and continuous, or has a set of openings A, such as windows, doors, and the like. The masonry <NUM> comprises a plurality of rod elements <NUM> attached to the masonry individually or, if appropriate or if required by specific contingencies and/or characteristics of the masonry, in parallel bundles. Such rod elements <NUM> are clamped and secured within respective hollow seats <NUM> by means of a fixing material <NUM> that thereby accomplishes the so-called "grouting" of the rod elements <NUM> in their respective hollow seats <NUM>. Such hollow seats <NUM> are carried out nearly vertically and mutually spaced apart on the accessible face F of the wall panel M.

In addition, for each hollow seat or group of hollow seats <NUM>, the masonry <NUM> includes a first reinforcing element <NUM>, elongated in shape, thin, with nearly parallel edges, and reproducing the shape of the portion of the accessible face F of the wall panel M adjacent to the longitudinal development of the hollow seat or group of hollow seats <NUM>. In other words, the first reinforcing element <NUM> is firmly attached to the portions of the accessible face F located laterally to a hollow seat <NUM> by rejoining, that is bonding, such portions separated by the hollow seat.

The tests and trials conducted have shown excellent behaviour and strength of the work described above, which, to achieve further improvement, may additionally include at least a second reinforcing element <NUM>, each attached to a respective curb element C and to the portions of the wall panel M or wall panels M adjacent to said curb element C, e.g., the upper and lower panels to the curb itself. An intermediate horizontal portion or lower edge of the wall panel M may also include a corresponding second reinforcing element <NUM> attached to the respective visible face F.

The second reinforcing element <NUM> mutually ties the curb element C and the respective wall panels M together making the latter capable of contributing to the reinforcement of the masonry and possibly allows the intermediate and lower portions of the wall panels M to be strengthened as well.

The portions of the accessible faces of the wall panels M carrying the hollow seats <NUM> and the first <NUM> and second <NUM> reinforcing elements and adjacent thereto shall be either bare or devoid or deprived of any coatings, such as plaster, panels, slabs, or the like, so that the reinforcing elements first <NUM> and second <NUM> can adhere directly to the brick, cement, or concrete. If the masonry is obtained from a construction having some claddings or clothing, this will be removed in the portions indicated above for the application of the first <NUM> and second <NUM> reinforcing elements and then restored where appropriate.

The vertical development of the rod elements <NUM>, fixed by means of the fixing material <NUM> in their respective hollow seats <NUM>, generally starts from the base or foundation of the wall panel M and their respective upper ends reach to heights less than or equal to the height of the respective wall panel M or reach the upper portion of the masonry by passing through, and being fixed to, all vertically overlapping wall panels M of the masonry <NUM>.

Each rod element <NUM> may have to be developed for a length even much greater than that which can be stored, transported, and easily handled, for said reason each rod element <NUM> may consist of one or more segments whose adj acent end portions are mutually connected and locked or secured by means of rings and/or sleeves and/or steel ties or resin-bonded banding. It is also provided that the ends of the rod elements may be provided with bonded sleeve, bonded and possibly taped "spigot" or a male and female screw connection.

As shown in the variant in <FIG>, the masonry may also include one or more optional holding element <NUM> made of fabric or glass fabric or mat or the like and having a tubular, sock or tape form.

Such holding element <NUM> is placed between the walls of a hollow seat <NUM> and respective rod elements <NUM>, wherein such at least one holding element <NUM> is at least partially encased in the fixing material <NUM>. The holding element <NUM> viewed in cross-section may be "U-shaped" with sides interposed between the walls of hollow seat <NUM> and rod element <NUM> or "O-shaped" in that it is wrapped around the rod element or shod around it; in either case, the fixing material <NUM> totally, or nearly so, impregnates or encompasses both holding elements <NUM> and rod element <NUM> and adheres to, and/or penetrates into the interstices of the walls of the hollow seat <NUM>. The holding elements <NUM> are particularly useful in hollow seats <NUM> made in wall panels M made of perforated or hollow bricks because they improve the attachment of the rod element and prevent leakage of the fixing material <NUM> into the cavities of the bricks by improving the adhesion of the rod elements <NUM>.

The invention provides that each rod element <NUM> can be fixed to the floor and/or roofing and/or foundation curbs by means of clamps, collars, pins, bandages, and the like secured to the curbs by means of screwed or secured with resins masonry pins.

Each rod element <NUM>, or respective segment, is made of composite material comprising carbon and/or glass and/or aramid and/or boron and/or basalt and/or high-density polyethylene or Dineema® fibres embedded in an epoxy or polyurethane resin matrix or embedded in adhesive mortars or grout or the like. Alternatively, the rod elements, or some of them, may consist of steel bars or pipes or cables. The surface of each rod element <NUM> may be provided with optional gripping means, assigned to improve coupling with the fixing material <NUM>, consisting of at least one of: adherent coating of sand or other rough material, cavities, transverse grooves or protrusions, or the like.

Each of the first <NUM> and second <NUM> reinforcing elements is fabric made of carbon and/or glass and/or other mineral or organic fibres such as aramid and/or boron and/or basalt and/or high-density polyethylene or Dineema® and the like or steel. Alternatively, the second reinforcing element <NUM> may be nonwoven fabric or mat of said fibres.

The fabric of the first reinforcing element <NUM> is preferably of a quadriaxial type and the fabric of the second reinforcing element <NUM> is preferably of a unidirectional, bidirectional or mat type wherein said fabrics are embedded in an epoxy or polyurethane resin matrix of the respective first <NUM> and second <NUM> reinforcing elements and adhered to the masonry <NUM>, securing said first <NUM> and second <NUM> reinforcing elements to the masonry itself; the fixing material <NUM> consisting of at least one of: high-strength mortar, epoxy resin, construction adhesives also incorporating aggregates and/or reinforcing fibres.

The invention provides that the wall panels M and, if any, curb elements C together with other building elements, are of a pre-existing construction and to be reinforced, and that the other constituents of the masonry (easily identifiable as they are marked by Arabic numerals) constitute the cooperating reinforcement with panels and curbs to give the masonry the desired resistance, for example to seismic events.

The method for carrying out the masonry, which is the object of the present invention, provides the following steps:.

The method further provides securing at least one second reinforcing member <NUM> to portions of the at least one wall panel M or wall panels M adjacent to at least one curb member C and to such at least one curb member C and/or securing at least one second reinforcing member <NUM> to at least one horizontal portion of the at least one wall panel M.

The method further provides securing each first reinforcing element <NUM> of the masonry <NUM> to the respective portion of the accessible face F of the wall panel M by securing a four-axial fabric thereof <NUM>, either having a different weft or weave or lacking the latters, by application to such respective portion of a resin in a fluid state assigned to imbibe the fabric and consolidate to embed or to encase the fabric and accomplish said fixing; and it provides the fixing of each second reinforcing element <NUM> of the masonry <NUM> to its respective surface portion by blocking a unidirectional, bidirectional, or differently textured fabric or fabric without any specific texture, of said second reinforcing element <NUM>, by application to such respective portion of a resin in a fluid state assigned to imbibe the fabric and consolidate to embed or to encase the fabric and to carry out said securing or fixing.

The method also provides removing, prior to the fixing of the first <NUM> and second <NUM> reinforcing elements, any plaster or other coatings of the portions of wall panels M assigned for said fixing. The coatings, whether of plaster, tiles, slabs, panels, or the like may eventually be applied or restored upon completion of the other steps of the method.

The method may further provide placing at least one optional holding element <NUM> made of fiberglass fabric or mat or the like in the form of a sock or tube or ribbon folded into place, against at least one wall of a hollow seat <NUM> caried out in a wall panel M made of perforated or solid brick, prior to the positioning and fixing of the respective rod element <NUM> into that seat by means of the fixing material <NUM>.

The method provides making hollow seats <NUM> at fixed or variable mutual distances depending on the peculiarities and characteristics of the masonry and the type and magnitude of stresses to which it might be subjected by foreseeable events. It is also contemplated to make hollow seats <NUM> at the sides of the openings A of the masonry panels of the construction and, if necessary, to fix the second reinforcing elements to the masonry panels, not only at the curbs but also at base or intermediate areas of the masonry panels, such as above and below the openings A.

Claim 1:
Reinforced masonry comprising at least one wall panel (M) having at least one accessible face (F) almost vertical and adjacent to a set of respective almost horizontal curb elements (C) each one associated with the at least one wall panel (M); said reinforced masonry (<NUM>) comprises a plurality of rod elements (<NUM>) fixed, individually or in bundles and by means of fixing material (<NUM>), within respective hollow seats (<NUM>) carried out, almost vertically and mutually spaced, at least in the accessible face (F) of the at least one wall panel (M), wherein each rod element (<NUM>) or respective segment is made of composite material comprising carbon and/or glass fibers or other mineral or organic fibres, embedded into an epoxy or polyurethane resin matrix or into adhesive mortar or the like, where the surface of each rod element (<NUM>) is provided with gripping means consisting of at least one of adherent sand coating or other rough material, cavities, transverse engravings or protrusions or similar, or it lacks them, characterized in that said reinforced masonry (<NUM>) comprises, for each hollow seat or group of hollow seats (<NUM>), a first reinforcing element (<NUM>) fixed to portions of the at least one accessible face (F) of the wall panel (M) which are adjacent to the longitudinal development of the hollow seat or group of hollow seats (<NUM>), and rejoining such portions separated by the hollow seat; and in that said reinforced masonry (<NUM>) further comprises, for at least one curb element (C), a second reinforcing element (<NUM>) fixed to said curb element (C) and/or to the portions of the wall panel (M) or of the wall panels (M) adjacent to it (C), and/or in that it comprises at least a second reinforcing element (<NUM>) fixed to at least a horizontal portion of the edge of the wall panel (M); each first reinforcing element (<NUM>) is made of fabric, as the quadriaxial type, and each second reinforcing element (<NUM>) is of fabric, as unidirectional or bidirectional, or is mat, where such fabrics or mat are in carbon and/or glass fibres and/or other mineral or organic fibres and are embedded into a resinous matrix of the respective first (<NUM>) and second (<NUM>) reinforcing element, and they adhere to the masonry (<NUM>) fixing these reinforcing elements (<NUM>, <NUM>) to the masonry itself; the fixing material (<NUM>) consisting of at least one of high-strength mortar and building adhesives, also incorporating inerts and/or reinforcing fibres.