ES2629607B2 - Connector device for wood and concrete collaborating structures and mixed structure incorporating a plurality of connector devices - Google Patents

Abstract

Connecting device for collaborating structures of wood and concrete and mixed structure incorporating a plurality of connecting devices. # The present invention relates to a connecting device for forming a mixed structure of wood and concrete, characterized in that said element comprises two ends coupled to a piece of wood and, between said ends, has a curved fork-shaped central part, where once the ends have been coupled to the piece of wood, at least a part of the curved central part protrudes from the piece of wood, such that said curved central part can be covered by a layer of concrete deposited on the piece of wood.

Description

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DESCRIPTION

Connector device for collaborating structures of wood and concrete and mixed structure that incorporates a plurality of connector devices.

TECHNICAL FIELD OF THE INVENTION

The present invention relates in general to the field of Construction, Building Structures and, to a lesser extent, Civil Works. More specifically it refers to the collaborating structures of wood-concrete and the connecting, anchoring and reinforcing devices thereof.

BACKGROUND OF THE INVENTION

The collaborating structures of wood and concrete are usually used in construction. This type of structure usually includes some type of connecting device to join both materials and ensure that the structure will withstand the corresponding efforts and behave in solidarity without separating both materials.

A connecting device for mixed wood-concrete structures consists basically of a screw or rod that is inserted into a piece of wood by direct tapping of a screwdriver, or with the preparation of a pre-drill, resin filling and insertion of a bar or rod. The head of the screw, bar or rod is designed in such a way that it increases the surface offered by the shaft, thereby improving anchoring with concrete and facilitating joint wood-concrete collaboration.

Originally, the state of the art conceived these connectors to be screwed perpendicularly to the horizontal surface of the upper face of the wooden beam or slab, which forces the screw shaft to work flexurally and the effort that the wood must absorb becomes in fiber crushing. Therefore, in regards to

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Minimum dimensioning of the thread of the thyme and in terms of the ability to absorb flush effort per screw unit, the design results in great improvements.

Many of the solutions offered by the state of the art to solve the problem of anchoring are merely screws or hexagonal head barbers to facilitate direct screwing on the wood or screws that are inserted through a mushroom that amplifies the surface in contact with the concrete. It is also contemplated to duplicate the screw to duplicate the anchor or introduce resins as a means of fixation instead of mechanical fixation.

Additionally, it is possible to improve the design of the anchorage by expanding the surface of the wood in a position to resist stresses, thereby reducing working stresses to avoid exceeding the resistant capacity of the wood, depending on the direction of the effort in relation to the main direction of the wood fiber.

However, the great difference of the resistant values of the wood depending on the direction of the effort is very important, especially in the direction perpendicular to the fiber and the crushing of said fiber continues to be a very common pathology in the wood joints that use tips or screws. Therefore, the state of the art would receive as an important contribution any progress in the design of a joint or anchor for the wood that tries to avoid transmitting efforts in the most vulnerable orientations, specifically the efforts perpendicular to the direction of the fiber.

SUMMARY OF THE INVENTION

The present invention solves the aforementioned problems by providing an anchor and reinforcement of mixed wood and concrete structures without interfering with the concrete assembly. For this purpose, in a first aspect of the invention, a connecting device for forming a mixed structure of wood and concrete is presented, wherein said device comprises two ends attachable to a piece of wood and, between said ends, has a central part curved in fork shape, where once the ends have been coupled to the piece of wood, at least a part of the curved central part protrudes from the piece of wood, such that said curved central part can be covered by a layer of concrete deposited on The piece of wood. Advantageously,

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thus the arch receives the flush forces of the concrete and transmits them to the wood, pulling the ends of the device that have been coupled into the piece of wood.

It is contemplated that the connecting device, according to one of the embodiments of the invention, has a tubular shape, the ends of the circular section and the central part of the oval section.

Alternatively, it is contemplated that the device is obtained from a flat die strip. In this case, according to one of the embodiments of the invention, it is contemplated that the ends of the strip comprise extensions of greater width than the central part, such that the ends of the device are formed by the winding of said extensions, producing a tubular structure of circular section at said ends. Another possible embodiment, starting from the die-cut flat strip, contemplates a fold in each of the ends of the strip, which defines a contact surface attachable to a piece of wood.

The device can be made of different materials, preferably metallic and to be selected from a bar, a tube, a flat plate, a perforated sheet or a mesh.

A second aspect of the invention relates to a wooden beam comprising a plurality of connecting devices such as those described above.

The beam receives the connecting devices with an inclination angle which, according to one of the embodiments of the invention, is preferably between 30 and 45 degrees with respect to the surface of said beam.

Additionally, the beam may comprise a recess configured to insert into it at least one connector device, a resin that retains the device in said recess and a spiral-shaped separator element, which wraps at least an insertable part of the connector device in the recess. . The recessing, according to different embodiments of the invention, can be carried out by means of a longitudinal groove along the wooden beam or by means of punctures for each of the devices.

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One of the embodiments of the invention comprises a wooden beam with a plurality of connectors of the type obtained from a flat die strip and with a fold at each end of the strip defining a contact surface that can be coupled to the beam, wherein said beam further comprises: a seat piece disposed on the surface of the wood, where the seat piece has a specific geometry that provides a certain angle of inclination to the connecting device; and a screw that fixes the contact surface of the connection device to the seat piece.

One of the embodiments of the invention comprises an arrangement of the devices in a transverse direction to the beam, where the minimum separation distance between one device and the next is at least the width of the fork formed.

One of the embodiments of the invention comprises an arrangement of the devices in a longitudinal direction to the beam, where the minimum separation distance between one device and the next is at least the height of the part of the device that protrudes from the surface of the wood.

Additionally, according to one of the embodiments, it is contemplated that the beam also comprises a concrete layer deposited on the surface of the wooden beam where the plurality of connecting devices has been arranged, where the concrete layer has a thickness that covers at least the plurality of connecting devices such that each of these can pick up an eventual flush of the concrete layer and transmit it to the wooden beam through its ends coupled to said beam.

Optionally, between the wood and the concrete layer, a waterproof-breathable sheet and a mesh compatible with the arrangement of connection devices coupled to the wood can be included in some embodiments of the invention, so that said devices are interspersed in some holes of the mesh.

The fork solutions of the present invention therefore allow to adapt to the specific needs of the concrete flush effort minimizing the perforations in the sheet that separates the wood from the concrete. Thanks to the multitude of variations and possibilities described in the different embodiments, the design of the bridge or the shape of the sheet, it is possible to adapt exactly to the calculation needs, using only the necessary material, and minimizing the perforations in the wood, that cease to be

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indiscriminate to become the object of specific calculation. In particular, the shape of the fork bridge can be extended both in the band of width, and in the extension of the band down, following the direction of the fork feet.

Perforated sheets and meshes, advantageously used as reinforcement of the fork bridge in some embodiments of the invention, improve the adhesion of the bridge with the concrete (stretched metal, wire meshes, or the like).

The punctual penetrations in the wood proposed by the present invention avoids the interferences that other continuous solutions produce on the concrete reinforcement mesh, usually placed in the lower part of the slab, that is, on the upper surface of the wood and simply supported by spacers anchored in their steel bars. Therefore, the use of forks as a punctual system, according to the present invention, allows to properly locate the anchors and position them advantageously in the appropriate places of the beam span, being able to vary their concentration and inclination of insertion depending on their relative position on the concrete beam or slab.

Additionally, in a multiple placement of forks aligned in the direction of the beam span, the bridges can be unified into a single sheet, as a centipede.

Other notable advantages of the present invention go through the simplicity of manufacturing of the proposed connector devices, since conventional steel profiles, meshes and sheets, formed by simple cold bending, can be used. Likewise, the ease and speed of circular section drilling improves the speed in the execution and insertion of the pieces.

DESCRIPTION OF THE DRAWINGS

To complement the description that is being made and in order to help a better understanding of the features of the invention, in accordance with some preferred examples of practical embodiments thereof, a set of drawings is accompanied as an integral part of this description. where, for illustrative and non-limiting purposes, the following has been represented:

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Figure 1 shows the operating principles of the present invention in a basic embodiment.

Figure 2 shows several arc shapes according to different embodiments of the present invention.

Figure 3 shows the insertion position of a connector according to the embodiment of Figure 1.

Figure 4 shows an alternative embodiment comprising a tubular connector with the crushed bridge.

Figure 5 shows an alternative embodiment comprising a variable section connector.

Figure 6 shows the insertion position of a connector according to the embodiment of Figure 5.

Figure 7 shows an alternative embodiment comprising a connector screwed to the piece of wood.

Figure 8 shows the insertion position of a connector according to the embodiment of Figure 7.

Figure 9 shows an embodiment of the invention comprising the insertion of multiple connector devices.

DETAILED DESCRIPTION OF THE INVENTION

The present invention relates to a connecting device for collaborating or mixed structures of wood and concrete.

Different embodiments of the present invention are presented herein, which respond to the same fundamentals and share basic characteristics such as the fork shape, which produces a concrete confinement effect; the legs or stirrups, which

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they fulfill the function of anchoring in the wood; and the fork bridge picks up the flush effort of the concrete beam or slab that covers the device and transmits it to the wood through its stirrups. In all cases, the forks can be placed perpendicular to the piece of wood, but its structural behavior improves by tilting it at an angle between approximately 30 ° and 45 °, which ensures that a compression rod is formed on the concrete of such so that the stirrups work with simple traction, without having to transmit other unwanted efforts that would cause crushing of fiber, fences or tears on the wood. The angle of inclination is not chosen arbitrarily but following a plan designed by the structural engineer to adapt the angle of insertion and the position of the ends of the connecting device to the state of solicitations of the wood-concrete assembly.

However, these embodiments should be understood with a non-limiting nature and only to help a thorough understanding of the invention. Thus, variations, changes and modifications thereof are possible without departing from the scope of the invention.

Particular implementations can be based on a wide variety of materials, from simple curved bars or plates, through mixed bar-sheet or bar-mesh solutions, to fork solutions in a single piece of sheet metal (smooth or perforated) or mesh mesh. stretched metal or similar. The different possible embodiments of the invention make it possible to adjust the quantity and type of material to each specific need. Simplicity is also valued in the drilling and insertion operations of the connector devices, to minimize the complexity, production costs and training needs of the entire construction process.

The insertion of the ends of the fork on the wood can be carried out on punched holes, in the form of a circular section drill, or linear grooves of rectangular section made with chain pickers or similar tools. Thus, the product of the perimeter of the section drilled (or grooved) by the length or penetration into the wood, determines the surface of adhesion with the resin and therefore the tensile strength of the anchor.

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The connecting device disclosed by the present invention allows the width between footboards (or fork width) to be adapted to suit the size of any mesh passage of the concrete reinforcement corresponding to the collaborating structure, so that it can be worked with mesh electro-welded without having to perform on-site assembly.

Figure 1 represents the basic operating principles of the present invention, where, in order to transform the flush stress (4) transmitted by the concrete (2) to the head of the anchoring element (3), by means of a simple tensile stress (5) in the axial direction of the shaft, it is necessary to tilt it around 30-45 °, measured with the direction of the concrete flush stress. The formation of a compression rod (6) between the head of the anchoring element and the surface of the wood (1) is thus achieved.

The correct inclination of the anchor bar is that in which the shaft works with pure traction, without transmitting pushes or slides of the concrete on the wood. Therefore, the optimum direction of the compression rod will be perpendicular to the surface of the wood to prevent slippage, so that there is a reaction to the flush of the concrete (9) that can decompose in a reaction in the stirrups of the fork to tensile stress (8) and a reaction of wood to compression stress (7). In this way, the concrete rod is simply compressed without having to evaluate friction efforts to balance the horizontal thrusts, which can be seen graphically in the polygon of out-of-balance (10).

On the other hand, it must be taken into account that there are limitations both in the maximum compressive strength of concrete (compression rod) and in the resistance to fiber crushing in wood. This entails a limitation in the effort to resist for each anchor bar, which will depend on the deflection surface of the fork bridge, which is responsible for receiving and forwarding the flush efforts of the beam towards the anchor bars. The present invention, according to one of the embodiments, contemplates optimizing the operation of this concrete connecting rod and shaft of the tensile anchor rods according to the modification of two parameters: the angle of connection of the bars, tubes or plates and the design of the bridge band, which

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will be responsible for resending the flush efforts of the beam perpendicular to the surface of the wood.

As regards the shaft of the anchor bar, it must transmit the tensile stress it receives to the wood. According to one of the embodiments of the invention, where the ends of the connecting device are embedded in a recess and fixed with resin, the stresses are transmitted to the wood through the entire surface in contact with the resin. A greater surface of contact with the resin implies a greater capacity to resist tractions, so the total tensile strength offered by each bar, plate or tube, depends on the product of the penetration length multiplied by the length of the cross section of the pre-drill practiced in contact with wood. That is, to increase the resistant capacity of each connector, the insertion length in the wood can be increased or the insertion section increased, or both. However, the insertion length is limited by the edge of the wooden beam or thickness of the CLT contralaminated board.

In one of the embodiments of the invention, where the recess is a linear (grooved) perforation, the direction of the bending beam span is followed, so as not to cut the wood fiber and not to limit its ability to work in bending.

The increase in the insertion section implies an increase in the section of the shaft, or an increase in the amount of resin per insert. Once the sturdy capacity of each fork is exhausted, the present invention contemplates adding additional forks at a certain distance to counteract the flush of the beam transmitted by the concrete.

As for the material of the connectors, when plates are used to form the fork bridge, according to one of the embodiments it is advisable that they have perforations to improve the adhesion with the concrete. Perforated sheets and meshes (stretched metal, wire meshes, or the like) are the most advisable for this use because they prevent the sliding between the sheet and the concrete, improving the confinement effect, thereby increasing its ability to transmit the concrete flush with less exposed surface.

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The set of embodiments presented below preferably uses steel bars or plates configured in the form of a fork, with their ends or stirrups anchored to the wood. The anchorage depending on the embodiment can be solved by means of a pre-drill and subsequent resin filling, such as an epoxy resin or similar, that guarantees adequate steel-wood adhesion, but the anchor is also contemplated by means of retention elements such as a screw , which allow you to do without resins. Four basic embodiments are then described to illustrate the possibilities of the invention, but combinations of features between them are equally possible and should be considered to be disclosed:

I. Fork anchors of constant section.

II. Anchors in a crushed tubular fork on the bridge.

III. Fork anchors of sheet metal or die cut mesh in variable section.

IV. Fork anchors screwed to the wood.

1st realization. Fork anchors of constant section.

The most basic embodiment, shown in Figure 2, consists of a bar of uniform section (21) curved in the form of a fork.

The fork is inserted into the wood by means of a pre-drill and subsequently filled with resin to the depth h2 (22), leaving the rest of the connector exposed to the concrete to the height h1 (23), which determines the maximum edge of the piece of wood and concrete. The figure clearly shows the elevation (24) of the fork and, at its base, is the plant-section (25) seen from below. The particular case represented corresponds to a circular section, but many other fork sections (27), such as square or rectangular, which can also be solid or hollow sections are possible. In the simplest case of bars of circular section, the adhesion to concrete is improved if the bars are corrugated. The elevation section (26) of the fork profile is also shown.

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According to different embodiments, the fork arch or bridge of the anchor connector device is solved with a simple semicircular arch (24), a three-center arch (28), with a flat bridge with rounded corners (29 ), or any other similar form that improves the confinement of the concrete flush.

Figure 3 shows, the fork insertion position, according to two particular embodiments of the invention, where a longitudinal section is shown in the direction of the concrete flush, with two different insertion angles (31, 32). The best grip position is to position the fork plane perpendicular to the direction of the concrete flush. The insertion angle determines the height (33) of the minimum concrete layer and the thickness or edge (34) of the piece of wood. The angle of insertion is adapted to the position of the fork in relation to the distance to the supports of the beam. The optimum inclinations, according to different embodiments of the invention, vary between 30 ° (32) and 45 ° (31). However, in some cases they can simply be placed at 90 degrees, perpendicular to the plane of the wood.

The distance between stirrups of the fork can be adapted to the separation of the bars of the distribution or reinforcement mesh so that they are compatible and does not interfere with the modulation of the forks with that of the mesh.

Figure 3 shows one of the embodiments of the invention where, in addition to the structural piece of wood (35), for example solid wood, laminated wood, CLT counter-laminated board or the like, a waterproof-breathable separator sheet (37) is shown, and a mesh and / or reinforcement (38) of concrete, a layer of concrete (39), and the forks (36) that are anchored in the piece of wood.

The anchoring of the forks is carried out in a recess that, according to different embodiments, can be a punctual perforation for each individual stirrup or, for example, a common linear groove for several connectors. Figure 3 shows a pre-drill (40) in the wood slightly larger than the section of the stirrups of the fork (36). Additionally, separators between the stirrup and the wood can be included, for example in the form of wire propellers (41) by the tips of the fork stirrups (36) to perform this separating function and ensure that the resin (42), which is injected later,

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Maintain a minimum thickness between the stirrups section and the recess (40) in the wooden beam.

2nd realization. Anchors in a crushed tubular fork on the bridge.

A second particular embodiment that enhances the benefits of the present invention, proposes, to achieve more width in the bridge and improve the confinement of the concrete to form the compression rod on the surface of the wood, use tubular profiles to make the fork, crushing previously the central area destined to be a bridge. Then, the bow or bridge of the fork is folded and shaped. The ends of the tubular part without crushing are inserted into the wood and the part exposed to the concrete is progressively adapting to the crushed shape that dominates the fork bridge in any of the possible arc geometries, as discussed above.

Figure 4 shows this particular configuration of the connecting device, where the fork (43) is shown in elevation, profile and upper and lower plan, with a central part, or bridge (44), clearly crushed and oval section ( 45), which is represented augmented to facilitate its appreciation.

As for the insertion of this connector in a wooden beam, it can be done in any of the ways mentioned above. For example, by preloading with a cylindrical drill, inserting a wire separator in a propeller that guarantees a minimum distance between the inserted bar and the recessed and then injecting a resin.

Since the fork bridge picks up the concrete flush and moves it to the wood by means of a tie rod mechanism, which avoids tearing or crushing of the wood fibers, the improvements derived from the bridge width improve the concrete confinement to the fulfill this structural function of transmitting the flush efforts of concrete to wood.

The proper inclination angle of the fork insertion (preferably between 30 and 45 degrees as discussed above) ensures that the fork stirrups

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work primarily in traction, as in the other embodiments presented.

Different types of section are possible with this same crushed bridge configuration. Thus it is equally possible to combine both solid and hollow sections, and in different formats, such as circular, square, rectangular, etc. In the case of bars of circular section (or similar) the pre-drill can be made, for example, with a simple drill and an electric screwdriver. In the case of bars of rectangular section (or similar) the pre-drill can be carried out in a simple way with a spindle mower or similar conventional tool.

3rd embodiment. Fork anchors of variable section

One of the embodiments of the invention is proposed to obtain the forks from a flat material, such as a flat sheet or mesh (perforated, unfolded metal, textile or similar) and trim a strip, for example by means of a die cut, of the desired measures , where preferably the ends of said strip are wider than the central part. This configuration allows, on the one hand, to bend the central part to form the curvature of the bridge and, on the other hand, it achieves a roller section at the ends of the connector.

One of the advantages of this embodiment resides in the simplicity with which a fork (50) can be formed as shown in Figure 5. Starting from a simple sheet or flat mesh (51) and by means of a simple die cut it can be used almost the entire sheet or surface base used for die cutting, obtaining strips (52) with a variable width, which is preferably larger at the ends. This optimizes the performance of the material used.

Once the flat piece (52) has been stamped, the ends of the sheet are curved in a circular section, taking advantage of its greater width, which will become the feet (53) of the fork. According to different embodiments, the winding of the legs (53) can be performed outwards or inwards. Then proceed to bend the bridge, which can be set flat or leave it with concave curvature. The bridge, either a flat arc or with concave curvature, can take any type of curving line as

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those discussed above (half a point, mixed arc, etc.); in any case it improves the confinement of concrete to collect the flush forces and forms the compression rod against the surface of the wood or CLT.

As for the insertion of the connector device of the present embodiment, the same configurations as previously mentioned are possible. Figure 6 represents a particular embodiment, where the present flat bridge solution inserted in a wooden structure (61) and concrete (62) can be seen in dihedral. One of the great advantages of this specific embodiment derives from having a circular section in the pins of the fork, such that the wood can be drilled with a conventional drill leaving holes (63) cylindrical in the wood. A suitable resin (64) is injected into the recesses for joining wood-metal (for example epoxy, resorcinum or similar) and placed in a spiral-shaped steel wire separator (65) to ensure adequate steel-separation. wood.

Additionally, it is contemplated to place a waterproof-breathable sheet (66) on the surface of the wood and the corresponding mesh or reinforcement necessary for the concrete before inserting the connecting devices of the present invention.

The width and height measurements of the fork can be adapted to the height variations of the piece of wood (67) and that of the concrete (68), as well as the measure of pitch width of the mesh or reinforcement (69).

As in the variants described above, the connectors are inserted according to a suitable angle (70) which, preferably, is 30 ° -45 °. Likewise, the inserts can be multiple both along and across the piece of wood or CLT.

4th embodiment. Fork anchors screwed to the wood

Alternatively to the above embodiments, a particular embodiment of the present invention is presented that dispenses with the use of resins at the ends. Figure 7 shows the main differences of this embodiment in different views of plan and profile elevation, where the replacement of the insertable stirrups of the previous embodiments of the fork by mechanical fasteners, such as self-drilling screws or bolts (72) ). The fork in this case is reduced to the bridge, which can be shaped by

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example with a sheet (73) or a plate (solid, tubular or perforated), making a folding in the ends, in which a perforation is practiced so that the chosen fastening element can pass. Between the fork and the pitch of the screwdriver, a transition washer (74) is fitted, adjusted to the head of the screwdriver so that the tensile stresses are transmitted properly, since the self-drilling screws usually have a low flying head. To adapt this set to the inclination of the angle of proper insertion (81), a seat piece (75) is added that is flat with the surface of the wood and allows the correct insertion and tightening of the screwdriver with the appropriate angle. This seat piece (75) is contemplated to be drilled according to the section of the screwdriver (72) to be used.

Figure 8 represents a connector (73) as described above inserted in a piece of wood (80) and confined by a layer of concrete (82). The optimal insertion angles and the intermediate configuration of a waterproof-breathable sheet (83) on the surface of the wood and the corresponding mesh (84) or reinforcement is identical to that of the previous embodiments. The fundamental difference lies in the addition of the seat piece (75), adapted to provide the desired inclination and the fastening of the connector (73) by means of a screw-type fastener (72), which crosses the end of the connector through a hole prepared for it.

Thus the present embodiment describes a fork anchoring system for mixed wood-concrete collaborating structures that can be anchored to the wood by means of screws or bolts directly screwed (with or without pre-drills). As for the efficiency and structural operation of this embodiment, it shares the same advantages as the rest of the fork variants, improving the confinement of the concrete with the flat arch bridge.

Figure 9 represents the possibility of, for any of the embodiments of the present invention set forth above, repeating the insertion of forks along the longitudinal direction of the beam or slab light, or, transversely, the system being able to extend both online as in parallel. To continue the repetition in line, it is required that the distance between two devices is sufficient for the compression rod to be formed on the concrete, this is roughly equivalent to respecting the separation distance between forks, at least the height of the fork protruding From the wood.

On the other hand, in the parallel direction, it is contemplated that the distance between two forks is at least the width of a fork, in order to respect the cutting area of the wood that is affected by the insertion of the fork shafts . The inclination of the forks can be varied depending on the relative position of each fork in the beam or 5 slab, to improve the collaboration in the transmission of the vertical shear of the wood-concrete flexural system.

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Claims (5)

5 10 fifteen twenty 25 30 1. - Mixed structure of wood and concrete comprising a wooden beam with a plurality of connecting devices to form said mixed structure of wood and concrete, formed from a flat die cut strip, where the devices comprise two ends attachable to the beam of wood and, between said ends, a curved fork-shaped central part, where once the ends have been coupled to the wooden beam, at least a part of the curved central part protrudes from the wooden beam, such that said Curved central part can be covered by a layer of concrete deposited on the wooden beam, where each of the ends of the strip has a fold that defines a contact surface attachable to the wooden beam, characterized in that the beam also comprises : - a seat piece arranged on the surface of the wood, where the seat piece has a specific geometry that provides a certain angle of inclination to the connecting device; - a screw that fixes the contact surface of the connection device to the seat piece. 2. - Mixed structure of wood and concrete according to claim 1, comprising an arrangement of the devices in a transverse direction to the beam, where the minimum separation distance between one device and the next is at least the width of the shaped fork. 3. - Mixed structure of wood and concrete according to any of claims 1-2 comprising an arrangement of the devices in a longitudinal direction to the beam, where the minimum separation distance between one device and the next is at least the height of the part of the device that protrudes from the surface of the wood. 4. - Mixed structure of wood and concrete according to any of claims 1-3 which further comprises a layer of concrete deposited on the surface of the wooden beam where the plurality of connecting devices, where the concrete layer is arranged has a thickness that covers at least the plurality of connection devices such that each of these can pick up an eventual flush of the concrete layer and transmit it to the wooden beam through its ends coupled to said beam. 5. - Mixed structure of wood and concrete according to claim 4 which also comprises, between the wood and the concrete layer, a waterproof-perspiration sheet and a mesh compatible with the arrangement of connector devices coupled to the wood, of such devices are interspersed in holes in the mesh.