ITSV20060014A1 - PANEL FOR THE REALIZATION OF FORMWORK CONTAINMENT WALLS FOR CONCRETE FLOOR PLANTS IN PARTICULAR FOR THE CONTAINMENT FORM FOR THE CONSTRUCTION OF CONCRETE OR SIMILAR INSOLES AND PROCEDURE FOR THE MANUFACTURE OF DETAILS - Google Patents

Description

"Panel for the construction of formwork containment walls for concrete castings, in particular for containment formworks for the construction of concrete slabs or the like and procedure for the manufacture of said panel"

TEXT OF THE DESCRIPTION

The invention relates to a panel for making containment walls for formwork for concrete casting, in particular for containment formwork for making concrete slabs or the like, which panel is formed by at least one layer of wood or similar.

The containment formworks for concrete castings are known and are formed by a plurality of panels which together form the concrete containment walls with the desired shape and dimensions and which panels are mounted so as to form said containment walls in a supporting structure.

As indicated above, each panel is composed of at least one layer of wood having dimensions of length, width and thickness such as to resist without deforming the stress of the concrete and at the same time, however, to present a certain ease of handling by the personnel assigned to transport and assembly. of the formwork. These dimensions, especially as regards the thickness, are substantially fixed. Therefore, the problem currently exists of how to increase the load resistance of the panels without modifying their thickness and in particular without increasing their thickness.

It is also known to produce panels of the aforesaid type in which the wood layer is protected along at least some lateral edges and / or parts of some lateral edges as well as along at least a part of at least one of the two faces by a covering layer. made of impermeable material such as resins, films or layers of plastic or the like.

Finally, it is known to realize the wooden part in the form of two or more layers, in which the strips of one layer and those of the adjacent layer are arranged crossed with each other and / or in the form of superimposed sheets of wood glued together and arranged crossed. regarding the orientation of the wood fibers of the individual layers, such as plywood sheets

Other known embodiments, on the other hand, have a layer of. wood or the like which is formed by shavings and / or powders pressed together and joined together by means of resins or glues, such as for example the so-called chipboards or the like.

In particular with regard to the construction of formwork walls for slabs, the panels must have sufficient resistance to bending under the weight of the concrete. In wooden strips, their resistance is greater in the longitudinal direction of the wood fibers than in the transverse direction.

Therefore the strips are made with their longitudinal axis oriented in the direction of the wood fibers which are highlighted by the natural joints of the wood, while the transversal head edges of the strips extend transversely to the orientation of the wood fibers.

Therefore, as regards the panel having a better resistance to bending, this must be formed by a plurality of adjacent strips arranged at least on one layer, i.e. coplanar with each other and oriented with the longitudinal axes parallel to the wood fibers and parallel to the longitudinal direction of the panel. , the adjacent strips being side by side and joined by chemical / physical adhesion, or by gluing at the longitudinal edges of mutual contact.

In this case, however, while the panel has a considerable resistance in the longitudinal direction of the strips, in the transverse direction to the longitudinal extension of the strips and therefore of the wood fibers, the individual strips are subject, over time and with use, to sling or arch giving the panel a curved or wavy surface or in any case not straight or flat.

In order to avoid this, the wooden panels are formed by a single layer or by three layers of wood superimposed on each other, each layer being formed by a plurality of side-by-side strips joined together along the longitudinal edges of the same and being however the strips of each oriented layer, with their longitudinal axes and / or with the wood fibers, in a transverse direction with respect to the longitudinal axes and / or the wood fibers of the strips of the immediately adjacent layer.

This solution ensures that no deformations of the panel occur in the direction transversal to the wood fibers and / or to the longitudinal extension of the strips and / or panels.

In mono-layer panels, i.e. formed by a single layer of adjacent strips joined together along the longitudinal edges, it is known to provide strips to stiffen the leading edges, i.e. the edges of the panel which are oriented transversely to the longitudinal extension of the strips and which consist of an overturned C or U-shaped section which is inserted over the terminal portion of one or each of said two opposite leading edges of the panel. The fixing of the stiffening profile can take place by simple coupling of shape and / or by forcing on the corresponding end of the panel or it is possible to provide a fixing by means of screws and / or also by gluing by means of adhesives or similar substances which are injected and / or applied both previously and subsequently between the profile and the end of the panel.

In this embodiment, the stiffening profile closes and / or covers towards the outside the leading edge of the panel which consists of the set of leading edges of the individual strips and whose leading edges are oriented transversely to the wood fibers, without however guaranteeing an effective sealing of said leading edges against the infiltration of humidity. Since it is precisely these leading edges which are transversal to the wood fiber orientation and are particularly permeable to water and / or to the infiltration of humidity, the stiffening profiles of the known type, even though they can effectively contribute to avoiding the panel warping in the direction transversal to that of the wood strips and fibers, they constitute an ineffective barrier against the infiltration of humidity, but effective against drying. That is, they generate a covering of the leading edges that allows water and humidity to penetrate, but which affects or otherwise prevents or slows down drying, thus favoring the deterioration processes of the wood due to the infiltration of humidity.

The invention has the purpose of realizing a panel of the type described at the beginning which, thanks to simple and inexpensive measures, can have characteristics of resistance to stress on the panel itself that are better or at least identical to those of the existing panels, effectively obviating the drawbacks of existing panels, namely allowing an effective increase in the load resistance of the panel without requiring thickness increases or complex and profound structural and material modifications of the panel itself.

The invention achieves the aforementioned purposes thanks to a panel of the type described at the beginning, that is, a panel for the construction of formwork containment walls for concrete casting, in particular for containment formworks for the construction of concrete slabs. concrete or the like, which panel is formed by at least one layer of wood or the like and in which at least one edge of the panel is oriented at least for a part of it in a direction transverse to the direction of the wood fibers and has at least for said part an edge of sealing which is of plastic material, overlaps the head side of the panel along at least said part of said edge and is fixed to said head side of the panel by chemical / physical adhesion, sealing it towards the outside.

According to a further feature, the said sealing edge is provided in combination with a stiffening profile or constitutes itself a stiffening element in combination with a reinforcement profile.

An advantageous embodiment of the panel provides a wood layer with at least one end wall of a perimeter edge of said wood layer, to which end wall a stiffening profile is fixed by mechanical or form coupling, which profile of stiffening protrudes, at least for part of its length, outward from said head side of the edge of said wood layer being embedded in a sealing edge of plastic material which overlaps the said head side of said edge of the wood layer , said sealing edge being coupled by chemical-physical adhesion to the head side of the edge of the wood layer and to the protruding portions of said stiffening section.

The mechanical coupling between the wood layer and the stiffening profile can be achieved by providing a stiffening profile with a central section shaped like a strip and with a widened end part along one of the two longitudinal edges, while in the thickness of the wood layer along the said head side of said edge a groove is made of a shape corresponding to the section of part of the strip and of said enlarged end part, which groove is open at least in correspondence with one of its head ends and said profile being engageable in said groove through said head side open, while the strip of the section protrudes for a certain length outside the head side of said edge of said layer of wood.

The sealing edge overlaps the entire thickness of the head side along the edge of the panel to which the stiffening profile is associated and also the entire protrusion of the stiffening profile beyond said head side of said edge of the wood layer .

The stiffening strip can be made of different materials such as plastic material, preferably plastic material of an identical or similar nature or a plastic material in any case chemically compatible with that of the sealing edge and / or also of metal material.

The protruding part of the stiffening strip can be provided with a surface treatment to roughen or increase the adhesiveness of the plastic material of which the sealing edge is formed.

The surface treatment can be a mechanical treatment, for example the provision of grooves or knurls in the surface of the stiffening profile and / or a chemical-physical treatment that modifies the physical or chemical conditions of the surface layer of the stiffening profile.

There are many possible variants.

According to yet another embodiment variant, the edge of the protruding part of the stiffening section can also be made widened with respect to the thickness of the flat part, similarly to the edge inserted in the groove provided in the edge of the wood layer.

The sections of the enlargements can be the same or different and any. A particularly simple form is a stiffening profile with a double T or H section.

A particularly simple embodiment provides that a T-shaped stiffening profile is associated with the panel, since said profile is engaged by forcing with the flap corresponding to the leg of the T-section in a groove provided in the corresponding leading edge of the panel. , while the flap that forms the crosspiece of the T adheres to it, covering and protecting the said leading edge. Advantageously, the flap that constitutes the crosspiece of the T ends flush with the faces of the panel.

Said T-shaped stiffening section can be provided both in the absence of the soft plastic material applied by injection and similarly to what is described above in combination with said plastic material applied by injection.

Further variants can be constituted by the number of layers of strips or wood material or similar joined together and which form the wood layer of the panel.

A first layer formed by a plurality of side-by-side wooden strips joined together along the mutual contact ends of the longitudinal edges of said strips can be coupled to a further layer or to several layers of wood fibers which in turn can be in the form of single or multilayer sheet, plywood and / or chipboard or similar type.

Alternatively or in combination with the first layer of strips, at least one further layer of wooden strips arranged side by side can be fixed in an overlapping position, directly or with the interposition of further layers of wood fibers of a different type and structure such as the one described above. to each other and joined together along the longitudinal sides of mutual contact of the longitudinal edges of said strips.

The at least two layers of strips can be arranged with respect to each other with the longitudinal axes of the strips oriented in different directions, i.e. crossed with each other. In particular, the arrangement can provide that the strips of one layer are oriented perpendicularly to the strips of the adjacent layer with reference to their longitudinal axes.

As regards the provision of the layers of strips, the invention provides that the layer of wood is formed by at least one layer formed by a plurality of side by side wooden strips joined together along the longitudinal sides of mutual contact of the longitudinal edges of said strips , since the wood fibers of the individual strips are oriented in the longitudinal direction of the strips themselves.

This can also be envisaged with regard to two or more overlapping layers of strips.

The sealing edge can be made of any type of plastic material. In particular, a soft or relatively soft and elastic plastic material such as soft polyurethane is used.

The application of the sealing edge preferably takes place by over-molding and in particular by injection. This mode allows not only to have a perfect sealing of the edge or edges of interest of the wood layer, but also to improve the mechanical anchoring of the stiffening profile. In fact, the plastic material injected for the over-molding of the sealing edge also penetrates into any voids due to construction tolerances and which are generated between the walls of the groove in the wood layer and the corresponding part of the stiffening profile inserted therein. This also favors the anchoring of the sealing edge which therefore has extensions in said groove.

On the other hand, the effect of improving the anchoring is further increased also by the combination of the rigid material of the same nature or of a similar nature to the soft material. In fact, the soft material applied by injection with the characteristic of penetrating better into the interstices between the stiffening profile and the engagement groove of the same and at the same time of penetrating even deeply into the interstices of the porosity of the wood acts synergistically with the effect of the best and more resistant mechanical anchoring of the stiffening profile to the wood.

When the edge of the wood layer to which the sealing edge is applied is oriented transversely to the fibers of the wood, it is obtained that the surface along said edge is rough or in any case porous and irregular, so that a better interpenetration is generated between said surface. of the wood and the plastic material of the sealing edge which therefore improves not only the mechanical anchoring, but also the sealing, generating a moisture barrier which has a certain depth of penetration into the wood layer.

A further advantage of the synergistic combination of the soft plastic of the sealing edge with the rigid plastic of the reinforcement strip is that the sealing edge can be made thicker without running the risk of being deformed by the load of the concrete. thanks to the presence of the rigid material of the stiffening strip. An edge of soft material of greater thickness or section naturally involves better protection against impact of the wood layer, as the greater the mass of deformable material and therefore able to absorb the energy of the impact. On the other hand, the presence of the rigid material allows the shock wave to be broken by absorbing and discharging the energy of the shock wave along its length and therefore reducing the local stress by diluting the local impact energy peak over a larger surface. yes absorption.

The panel can provide in combination on one or both faces one or more external covering layers having a moisture barrier function, as well as anti-adhesion as regards the concrete.

These coating layers can be constituted by thin films of resins, paints, or the like or by layers of plastic materials, for example of the type consisting of decayed polypropylene with vegetable flours and known for example by the name of Wood-Stock ®. Said coating or protection layers can be sealed together by chemical / physical adhesion to the sealing edges thus generating a sealing jacket of the inner wood layer which is of plastic or resin material and which is sealed on all sides. by means of said chemical / physical adhesion, for example welding, gluing or the like.

In the case of the example indicated above, the sealing edge is applied to the panel already provided with the wood layer and a covering or protection layer on at least one side, so that during molding the material forming the edge overlaps the head surface of the edge of the wood panel and the corresponding thickness of the edge of the coating and / or protection layer.

With particular reference to the case in which the first layer of strips can be fixed in a superimposed position, directly or with the interposition of further layers of wood fibers of a different type and structure such as the one described above, at least one further layer of strips of wood arranged side by side and joined together along the longitudinal sides of mutual contact of the longitudinal edges of said strips, it was also found that it is very advantageous to provide at least two superimposed layers of wood each formed by a plurality of side by side wooden strips joined together them along the longitudinal sides of mutual contact of the longitudinal edges of said strips, the wood fibers of the individual strips being oriented in the longitudinal direction of the strips themselves

Advantageously in this configuration, the position of the strips of a first layer is transversely offset with respect to the position of the strips of at least a second adjacent layer in such a way that the longitudinal surfaces of mutual contact and union of the strips of said first layer are to fall into a position that does not coincide with the longitudinal surfaces of mutual contact and union of the strips of said second layer, ie in a position coinciding with an intermediate longitudinal axis of the strips of said adjacent second layer and obviously vice versa.

The aforesaid configuration has considerable advantages. On the one hand, from a mechanical point of view, the panel is more resistant to loads with reference to its extension parallel to the longitudinal extension of the strips. In fact this longitudinal direction is essentially parallel to the orientation of the wood fibers and therefore to the condition in which the wood material exerts its greatest mechanical resistance to load. The at least two layers of wood each formed by a set of side by side strips joined together which strips are oriented with the longitudinal axes parallel to each other and which longitudinal axes are essentially parallel to the orientation of the wood fibers therefore guarantee an increase in resistance with respect to the load with reference to said longitudinal direction of the panel. This increase allows to have a wood layer of the panel formed by only two layers of strips and which has a load resistance higher than the resistance provided by a usual panel having a wood layer formed by at least three layers of overlapping strips and in which the directions of the strips are crossed with each other. Obviously, the resistance to the load in the transversal direction of the strips and the resistance to deformation or transversal warping of the panel is guaranteed by the presence of the reinforced sealing edges at least along the two leading edges of the panel oriented transversally to the longitudinal axis of the strips and / o Orientation of the wood fibers.

The advantages of this embodiment, however, go beyond what has already been indicated above since, since the strips of the individual layers are parallel to each other, both in relation to the direction of the longitudinal axis and in relation to the direction of the wood fibers, the surfaces of the leading edges of the strips are oriented in the direction transversal to the wood fibers, they are provided for the entire panel only along the two transverse edges of the panel.

Furthermore, taking into account that the absorption of water or humidity from the surfaces of a batten which are oriented parallel to the wood fibers are negligible, then it results that the sealing against the infiltration of humidity and / or water is only necessary along the said two edges. of the panel in correspondence with which they are located or which are formed by the head sides of the strips.

If there are two or more layers of wood fibers and in particular two or more superimposed layers of strips, it is possible to provide a single stiffening strip for each leading edge of the panel or a stiffening strip for each layer of wood. or for a subset of strata with respect to the general number of strata.

The insertion groove of the strip can be made within the thickness of one layer or can extend over the thickness of several adjacent layers. Obviously the dimensions and the shape of the section of the stiffening strip must correspond to those of the groove.

Another advantageous feature of the present invention which can be provided separately or in combination with the previous features, provides that the wood layer has recessed corner areas which are filled with inserts of plastic material with a shape such as to complete the perimeter shape. of the panel to an ideal shape provided for it in the absence of said recessed areas.

The recesses at the corner areas of panels having square, rectangular or polygonal shapes are provided with a curved U-shaped wall that opens towards the edge corresponding to the transverse side of the panel.

When a sealing edge is provided, said sealing edge can be connected with the plastic filling of at least one of said recesses.

In particular, said sealing edge joins together the filling material of two recesses at the corner areas at the two ends of said transverse edge of the panel.

The sealing edge can be made reinforced similarly to what was described above and the reinforcement element can also extend into the recesses of the corner areas being incorporated into the filling plastic material similarly to the sealing edge area.

The reinforcement element can consist of a stiffening strip which is inserted in a groove along an edge, preferably a transverse edge of the panel.

The said groove opens with each of its ends into one of the two recesses of the panel provided in the opposite corner zones at the ends of the said transverse edge and the stiffening strip can be of such length as to protrude in one or both of said recesses at least for a part of their extension in a direction parallel to the transverse edge of the panel,

It is also possible to provide that the end or the two ends of the stiffening strip protruding into the corner recess (s) of the panel are bent in such a way as to extend for a certain depth of the corresponding recess in the direction of the extension of the recess is parallel to the transverse edge which parallel to the longitudinal edge.

The filling of the recess or recesses is carried out by over-molding one or more edges of the wood layer and / or at least a part of this or of these, the sealing edge being achievable at the same time with the said operation, for wherein the sealing edge portion and the recess fill (s) are made of one piece and of the same material.

The recesses in the wood layer which constitutes the core of the panel and which are filled with plastic material, in particular of the soft type as for the stiffening edge and which are also at least partially reinforced, give a high level of protection to the areas of corner of the panel which are the areas most subject to damage during the transport, assembly and / or dismantling phases of the formwork.

The presence of the continuous and one-piece reinforcement with the sealing edge increases the mechanical strength of both the anchoring to the wood layer and relative to the absorption of mechanical stresses, especially those caused by impacts.

As already highlighted above, a synergistic effect is generated between rigid material and soft material which is not limited to the simple combination of the mechanical effects that each of said materials entails, namely the sealing, the best interpenetration between the soft material and the wooden panel and the action of absorption of the impact energy for the soft material and the action of stiffening and increasing the mechanical resistance as well as the best mechanical anchoring by means of reciprocal engagement elements between the rigid material element and the panel. In this case, the presence of the rigid material confers greater resistance to bending and deformation even of the soft material, so that it is possible to provide a sealing edge of soft material with a larger section and therefore with a better elastic energy absorption effect. impact, while the stress of the load on the panel does not substantially deform the edge of soft material to which the core in rigid material confers greater resistance. On the other hand, the soft material increases the mechanical coupling between the rigid material and the panel by eliminating any interstices, while the rigid material constitutes an element that is able to discharge local stresses due to impacts on larger surfaces, thus breaking the wave of impact and assisting the protective action of the edge in soft material.

The presence of a U-shaped terminal recess in the wall of the recess facing the transverse edge of the panel increases the contact surface between the plastic filling insert and the wood layer, thus avoiding detachment even in conditions of sudden stress, for example in the event of a collision.

The invention has additional features that are the subject of the sub-claims.

The characteristics of the invention and the advantages deriving from them will be better understood from the following description of a non-limiting executive example illustrated in the attached drawings, in which:

Fig. 1 schematically illustrates a first embodiment of the invention with an enlarged section of the terminal part of a panel at one of the transverse edges of the same and according to a perpendicular, longitudinal plane.

Fig. 2 shows a variant of the embodiment according to fig.

1 in which the panel is made up of two layers of wood.

Fig. 3 illustrates the embodiment of Figure 1 in which the wood layer is coated on both sides with a waterproofing and protection layer.

Fig. 4 shows a variant of the embodiment according to fig.

2 in which the wood layer is coated on both sides with a waterproofing and protection layer.

Fig. 5 shows an exploded view on the transverse head side of a panel according to the variant of Figure 3, the stiffening strip and the sealing edge being omitted.

Fig. 6 shows an exploded view on the transverse head side of a panel according to the variant of Figure 4, the stiffening strip and the sealing edge being omitted.

Fig. 7 shows in perspective the arrangement of the strips on the two layers of strips which form the wood layer of the variant embodiment according to Figures 2 or 4.

Fig. 8 shows a plan view of the wood layer of the panel according to a further feature of the invention consisting in the presence of recesses in correspondence with the corner areas of the wood layer, the wood layer being formed by one, two or more layers of strips side by side.

Fig. 9 illustrates the panel according to fig. 8 in which a transverse head side of the panel (the left one) is provided with the stiffening strip and the sealing edge and the fillings of the recesses of the wood layer, which sealing edge and which fillings are in one piece and incorporate the itself, while the opposite transverse head side (the right one) has only the strip, the part of the edges for sealing and filling the recesses shown in dashed line.

Fig. 11 illustrates an enlargement of an executive variant of a panel according to the teaching of figures 8 to 10 in which the recess has a different shape.

Fig. 12 is a view similar to that of figures 1 to 4 of a further embodiment of the invention.

It is important to underline that the examples described in the following description are not to be intended in a limiting way and that these constitute only specific choices between different executive variants, in which the configuration of the panel is a preferred configuration or a configuration from which the inventive teaching.

Generally the panels for the construction of formwork have a length between about one and three meters and a width between about 0.5 meters and 1.5 meters, being the length greater than the width (therefore a rectangular shape) and a thickness that varies depending on the materials and the structure from a few centimeters to a maximum of ten centimeters. As regards the above, these are maximum and minimum measurements which also vary according to the configuration of the frame or the bearing frame in which the panels are mounted side by side to create the containment walls of the formwork.

With reference therefore to Figure 1, this illustrates a panel according to a first embodiment of the invention in which the panel has a minimum configuration as regards the number of layers and the number of construction parts.

The panel according to Figure 1 comprises a layer of wood of which only the part is shown in correspondence with one of the two opposite edges oriented in the direction of the width of the panel and referred to in the present description and in the claims as transverse edge.

In the thickness of the transverse edge of the wood layer 1 a T-shaped groove 2 is made in which the crosspiece of the T is parallel or essentially parallel to the thickness surface 101 of the edge and the shank of the T is perpendicular to the said surface of thickness 101 and flows into correspondence with it. On at least one of the two longitudinal sides, i.e. at the ends of the transverse edge of the panel, said groove 2 is open in order to allow the insertion of a stiffening profile 3. This has a T-section corresponding to that of the groove 2 in terms of dimensions and forms, however, the leg of the T being of such length as to protrude beyond the thickness surface 101 of the transverse edge of the wood layer.

Figure 1 is a schematic figure and the stiffening profile has dimensions corresponding to those of the groove 2 and in any case such as to allow it to be inserted even with a certain force into the groove by sliding it in the axial direction. It is also possible to provide that the stiffening profile 3 has such dimensions with respect to the groove as to generate a shape coupling and / or even by forcing or that said dimensions are slightly smaller than those of the groove.

In all the aforementioned cases, what figure 1 and the subsequent analogous figures want to mean is that when a terminal sealing edge 4 is made of plastic material, and in particular when said edge is made by injection over-molding , the plastic material of said edge can penetrate into the desired or accidental cavities or voids present between the walls of the grooves 2 and the profiled element 3 and fill said voids by integrating the profiled element to the groove.

The stiffening section 3 can have an enlargement 203 also at the ends of the part protruding out of the groove. In the figures, the stiffening profile 3 is made with an overturned H or double T section being provided with a central strip 303 along each of whose longitudinal edges one of the side fins 103, 203 of the double T or H section is provided.

The sealing edge of plastic material 4 extends along the entire edge of the wood layer in which the groove 2 with the stiffening profile 3 is provided. The said sealing edge extends over the entire thickness of the surface 101 on the said edge. of the wood layer so as to completely cover it and completely cover the part of the stiffening profile 3 which protrudes out from the edge of the wood layer 1.

In this way the panel consists of at least one wood layer 1 at least one of the edges of which is covered by a sealing edge with a reinforcing element.

The stiffening effect determined by the stiffening strip 3 and the sealing edge 4 joined together by chemical / physical adhesion, can also be obtained by providing a stiffening strip which is embedded in the sealing edge 4 and which however does not have any anchoring. mechanical to the wood layer 1. The fact of providing a reciprocal mechanical engagement further solidified by the possible material of the sealing edge 4 between the stiffening strip and the wood layer 1 further increases the stiffening effect and at the same time improves the anchoring the sealing edge to the wood layer 1 and thus also improves the sealing effect by increasing the adhesion strength between the sealing edge and the leading surface of the edge of the wood layer 1 to which the sealing edge is applied .

The stiffening strip can be made of any material suitable to confer the required mechanical resistance in particular to the deformation of the wood layer under the effect of the load. In particular, the use of a metal or plastic material is envisaged for the stiffening strip. The sealing edge is also made of plastic. A soft plastic material such as polyurethane or the like is preferable for this sealing edge. Advantageously, the plastic material of the sealing edge is of the injectable type and can be applied to the wood layer by over-molding on the edge of the wood layer.

The stiffening strip 3 can be made of an identical or compatible plastic material so as to obtain the best adhesion between the strip and the plastic material of the sealing edge.

When a metal material is selected for the stiffening strip, the adhesion between said stiffening strip and the sealing edge material can be increased by means of a roughening treatment of the surfaces of the strip such as knurling or the like.

Roughening treatments can also be provided if the stiffening strip is made of plastic.

As shown in Figure 2, the wood layer can be composed of two or more superimposed wood layers 1A, 1B. These layers can each have a different structure. One of the layers or part of these layers or all of said layers can be made from sheets of wood similarly to plywood panels. One of the layers or part of these or all of the layers can be formed of particle board or the like. One of the layers or at least part of these or all the layers of wood can be composed of a plurality of strips placed side by side so as to form a continuous layer. The wooden slats can be continuous for the entire length of the wood layer or they may have a shorter length than the length of the wood layer 1A, 1B, since the wooden slats are arranged side by side with each other laterally and longitudinally.

Figures 4 and 5 illustrate further variants of the panel according to the invention. In this case the configurations of Figures 1 and 2 are further combined with coating and protection layers of at least one preferably of both faces of the wood layer 1 or 1A and 1B. The coating and protection layers indicated schematically with 5 in figures 3 and 4 can be made up of paint or resin films or layers of plastic material in the form of plates applied by gluing or other type of adhesion or anchoring to the wood layer. . In particular, the covering and protection layer or layers 5 may consist of polypropylene plates loaded with vegetable flours, for example plates of a material known under the commercial name of Wood-Stock®. In these cases, the coating and protection layer (s) 5 are applied before applying the sealing edge or edges 4, so that when applying these sealing edges 4 the said sealing edges 4 overlap. to the head sides of the edges of the covering and protection layers 5 by connecting to the same so as to generate a sealed joint. The coating and protection layers 5 therefore adhere hermetically to the sealing edges 4 by means of chemical and physical adhesion of the plastic materials that make up the said parts.

Although the sealing edges 4 as well as the stiffening strips 3 can be provided along each perimeter edge of the wood layer with or without covering and protective layers 5, the invention provides a further improvement which contributes to increasing the load resistance of the panel at least in a direction of extension of the same without requiring an increase in thickness or weight of the panel and which at the same time eliminates the need to cover the edges of the wood layers on all sides of the same.

Figure 12 illustrates a wood layer 1 which can be formed by a single layer or by two or more layers similar to what was previously described and which is provided in combination with a T-shaped stiffening strip 3. In this case the The fin 303 which forms the stem of the T-shaped section of the strip 3 is engaged, for example, by forcing or by friction in a groove 2. This is made in the thickness of the panel along an edge of the panel itself, while the fin 203 which forms the crosspiece of the T covers outwards the head side on said edge of the panel. Advantageously, but not necessarily, the said fin 203 which forms the crosspiece of the T-section has a width corresponding to the thickness of the layer 1 and covers the said leading edge for the entire thickness ending with the lateral edges flush with the two faces of the layer 1.

The T-shaped section described above can be provided without a sealing edge 4 being applied or as in the examples of Figures 1 to 4 in combination with a sealing edge of soft plastic material preferably applied by injection.

With reference to Figure 5, it illustrates a layer of wood 1 composed of two layers 1A and 1B of overlapping wooden strips. As shown in Figure 5, the wooden strips 6 of the individual layers are arranged with their longitudinal axes oriented parallel to each other, contrary to what happens in the layer of the art. Each layer of strips 1A, 1B is composed of strips side by side side by side and connected by chemical / physical adhesion in correspondence with the lateral surfaces of mutual contact. When the length of the laths corresponds to the size of the wood layer in this direction of the laths, then there are no laths placed side by side with each other in the longitudinal direction. Otherwise, the strips are side by side also longitudinally as the contact head surfaces are oriented transversely to the longitudinal axis of the same provided offset with respect to the contact head surfaces of two successive strips in a laterally adjacent position to the first ones.

Furthermore, the two layers of wooden strips are arranged superimposed on each other with the longitudinal lateral surfaces of mutual contact of the strips of a layer arranged laterally offset and in a position coinciding with an intermediate longitudinal axis of the strips of the layer 1 B adjacent to the wooden strips .

The individual layers 1A and 1B of wooden strips as well as the wooden strips 6 are glued together in a manner known per se to the person skilled in the art.

According to an advantageous characteristic, the strips are made with their longitudinal axes oriented in the direction of the fibers and therefore of the grain of the wood itself. Thanks to this characteristic, each strip and consequently the panel has a greater resistance to load with reference to the longitudinal extension of the strips and therefore of the panel since the wood has a greater resistance to stress in the direction of the fibers and veins.

In the transverse direction, on the other hand, the panel has a lower resistance to load, but since said dimension is smaller than the longitudinal one and a stiffening strip 3 is provided at least on each transverse edge of the panel, deformation or warping of the panel is effectively avoided. transverse direction of the same.

A further feature of this configuration makes it possible to avoid the coating at least of the longitudinal edges of the wood layer, 1, since the absorption or penetration of moisture through the surfaces of the strips oriented parallel to the fibers and therefore to the grain of the wood it is considerably lower than the absorption and penetration of moisture through surfaces which are oriented transversely to the direction of the wood fibers.

The edges of the wood layer oriented in a transverse direction, i.e. in the direction of the width of the panel, are therefore formed by the head sides 106 of the strips which are oriented in a transverse direction to the fibers of the wood and to the grain of the same,

The sealing edge 4 is applied to said transverse edges of the wooden panel. In combination with said sealing edge, the corresponding stiffening strips 3 can also be provided along the transverse sides of the panel.

The construction of these is similar to what has already been described above. The sealing edge 4 applied in particular by overmoulding to the end sides of the strips oriented transversely to the wood fibers means that thanks to the greater porosity of these surfaces, the plastic material forming the sealing edges 4 can penetrate to a certain extent into the pores and between the wood fibers, resulting in an effective sealing action against the penetration of moisture and in addition a better anchoring of the sealing edge 4 to the surface of the edge of the wood layer which in addition to the chemical / physical adhesion of the plastic material also generates a mechanical adhesion due to the interpenetration between said plastic material and the wood fibers.

As previously described with reference to Figures 3 and 4, the wood layer 1 or the superimposed layers 1A and 1B can be covered on their outward facing faces by a coating and / or protection layer 5. coating and protection layers 5 consist of paint, resin or plastic material in the form of films or plates which are joined by chemical / physical adhesion to the layer or layers of wood, while the sealing edge 4 overlaps the top surface also of the edge of said coating and protection layers 5 in correspondence with the edge of the layer or layers of wood 1, 1A, 1B to which said coating and protection layers 5 are coupled, joining said sealing edge 4 in a hermetic manner with the corresponding edge of said coating and protection layers 5 by means of chemical / physical adhesion.

Obviously, nothing prevents a sealing edge from being provided also at the longitudinal edges of the wood layer or layers 1, 1A, 1B.

Again with reference to the embodiment in which the wood layer is formed by several layers 1A, 1B of wooden strips which layers are superimposed on each other, it is possible to provide along at least one edge of the said wood layer a stiffening strip 3 for each edge is common to the two or more layers or a stiffening strip 3 associated with each layer 1A 1B of strips.

In the case of the example illustrated in the first variant, the groove 2 and therefore the stiffening strip 3 can extend in the direction of the thickness of the wood so as to pass through more than one layer completely and / or partially with reference to the thickness of these, see figure 2 and 4. With reference instead to the second variant, a groove 2 is provided made in the thickness of each layer of wood 1A, 1B and which is intended to house a stiffening strip which engages with the strips of a single layer of strips 1A, 1B. this configuration is not shown specifically, but it is clear if the configuration of figures 1 is considered suitably changed in the sense that two elements according to figure 1 are superimposed on each other with the sealing edge 4 ending flush. It is also possible to provide different protrusions for the two or more stiffening strips and therefore different protrusions of the sealing edge 4 at the level of each layer of strips and / or of each stiffening strip 3. it should be noted however that also in this case, it is preferable that the sealing edge 4 is made in one piece, for example by over-injection molding.

Figures 8 to 11 illustrate a panel according to the present invention in which the panel has a further characteristic whose function is to protect the corner areas which are the most sensitive to damage. In this case, a panel of rectangular, square or polygonal shape has at least four or more corner areas and the panel is formed by a single or multilayer wooden plate 1 having the rectangular, square or polygonal shape which plate has some recesses 7 in correspondence of the corner areas. The said recesses pass from face to face of the wooden plate 1 and are filled in such a way as to complete the wooden plate in the area of said recesses in order to obtain the overall rectangular, square or polygonal shape by means of an insert of plastic material which adheres to the thickness surface of the edge of the wooden slab 1 by adhesion

chemical / physical. The fillings of completely 8 are preferably made of soft plastic, such as soft polyurethane which is applied by molding to the corresponding corner area

re-entrant of the wooden plate 1.

The recesses can have different shapes and sizes and

in particular they are completed by means of the plastic insert 8 in such a way that it has a first perimeter edge

which is joined flush as a continuation of a parallel first edge

perimeter of the wooden slab or of a first perimeter sealing edge 4 and a second perimeter edge which is flush connected as

continuation of a parallel second perimeter edge of the slab of

wood or a second perimeter sealing edge which first and second perimeter edges have incident directions and form a corresponding corner area of the panel.

With reference to the embodiment illustrated in figures 8 to 10,

the recesses 7 of the wooden plate are provided with an edge 107 parallel to the edge in the direction of the width of the panel or of the

wood 1 which is made concave curved. So

the insert 8 has an arched extension that fits into the recess with a certain shape coupling. In addition to the increase of

overall adhesion resistance due to the increase in the surface

of contact between the delimiting wall of the recess 7 and the corresponding one

plastic insert 8, the concave edge 107 of the recess 7 and the arched end that engages in the same of the filling 8 form a sort of shape coupling which helps to increase the coupling resistance of the two parts and to improve absorption impact stresses by the plastic insert 8 avoiding damage to the wooden part 1, i.e. the slab 1. The plastic inserts 8 are better protected against detachment due to an intense and sudden stress such as an impact or similar on the corner areas of the panel.

This feature can be provided separately or in combination with one or more of the features or combinations of features described above.

Therefore it is possible that a panel is formed by a wooden plate 1 with any structure and in which only the corner areas are formed by completing inserts 8 of plastic material of corresponding recesses of the corner areas of the wooden plate 1 .

It is also possible that a panel, as indicated in Figure 9, has a wood layer 1 in which a sealing edge of the wood layer is provided along at least one edge, which sealing edge 4 connects the fillings 8 of the recess 7 to each other. correspondence of the corner areas of the wood layer.

In this case the sealing edge 4 can be limited to one of the edges of the panel or to two opposite edges or said sealing edge can extend along the entire perimeter of the panel.

In Figure 9, the sealing edge 4 is provided on two opposite edges of the panel oriented in the direction of the width of the panel, the sealing edge 4 being on the right side illustrated by a dashed line, i.e. not yet applied to the wooden slab 1.

The sealing edge 4 and the fillings 8 at the corner corners of the panel are made of plastic material preferably identical or in any case compatible with each other. Preferably the said sealing edge 4 and the fillings 8 are made by simultaneous injection overmoulding and with the same material such as polyurethane for example. In this way, a sealing edge 4 and fillings 8 connected to it are obtained which are formed by a single body, ie one-piece.

As further illustrated in Figure 9, it is also possible to provide in combination with stiffening strips 4 which are embedded or incorporated at least in the sealing edge 4.

These strips are made according to what has already been described above, the groove 2 being provided in the edge of the wooden plate 1 in such a way as to open with at least one head side open into the corresponding recess 7 of the wooden plate 1. Alternatively, the groove 2 opens with each of its head ends open into the corresponding recess 7.

Under these conditions, as a further improvement it is possible to provide that the stiffening strip in the position inserted in the groove protrudes at least for part of the corresponding depth in one or both of the corner recesses 7 of the wooden plate.

This condition is illustrated in figure 9 and in the enlarged detail of a corner area in figure 10.

As further indicated by the dashed lines that schematically identify the surfaces of mutual contact 106 between wooden strips 6, the wooden plate 1 can be formed by a plurality of strips placed side by side and joined together at the longitudinal sides 106. In this case, preferably the longitudinal orientation of the wooden slats 6, i.e. the longitudinal axis is provided parallel or approximately parallel to the fibers or grain of the wood, the wooden slab having a configuration therefore like the one previously described, and the slats being stiffening and the sealing edge provided along the edges of the wood panel or slab 1 which are transversal to the orientation of the wood fibers or grain. Also the concave wall 107 delimiting the recesses 7 in the corner areas of the wooden plate 1 are oriented aligned in a parallel or substantially parallel direction or in any case facing towards the said transversal edges of the wooden plate 1 or of the panel, so that even in in this case, precisely in the region of said arcuate part, the plastic material of the filling 8 penetrates the pores of the wood along the arcuate surface of the recess 7, further increasing the adhesion resistance.

Obviously, the wood layer can be formed by one, two or more layers of strips and in particular when it is a question of several layers the strips can be arranged as taught in figures 5 and 6, i.e. with the contact surfaces 106 between adjacent strips of a layer IA of strips 6 arranged laterally offset with respect to the contact surfaces 106 between adjacent strips of the adjacent superimposed layer 1B of strips 6, the said contact surfaces 106 of a layer 1A falling in coincidence with an intermediate axis of the strips 6 of the adjacent layer 1B of strips and vice versa.

As already mentioned previously, in this configuration it is possible to provide a single stiffening strip 3 for the set of layers 1A and 1B that form the wooden plate or a stiffening strip 3 for each layer or for at least a part of the layers provided.

It is therefore evident that the characteristics of figures 8 to 11 can be provided both independently of the characteristics, both single and in combination relating to the embodiments of figures 1 to 7.

The shape of the recesses 7 in the corner zones of the wooden slab 1 is not limited to what is described in figures 8 to 10, but can also be different as indicated in figure 11. In this case, each corner zone of the wood slab wood 1 according to one or more of the possible constructions or configurations for this wooden slab 1 can be made recessed both in the longitudinal direction and in the transverse direction, ie in the direction of the width of the panel. This can be achieved by creating the recess in the corner areas of the wooden plate 1 with a delimiting wall in the form of a double step. Also in this case, the realization of the fillings 8 in combination with the sealing edges and with the possible or eventual stiffening strips can be as previously described with reference to the variant of figures 8 to 10.

Again with reference to the embodiment of figures 8 to 11, the wooden plate 1 can be covered with a covering and protection layer 5 on both visible faces of the panel. In this case, the covering and protection layers 5 can have a shape similar to that of the wooden plate 1, i.e. provided with the recesses 7 in correspondence with the corner areas, while the plastic fillings 8 overlap the surfaces of head along the delimiting edges of the recesses 7 also of the coating and protection layers 5, connecting with these so as to generate a watertight seal. Alternatively, however, the coating and protection layers 5 can also overlap the two front sides of the fillings 8 and / or also of the corresponding sealing edges 4 which connects to said fillings 8, presenting the said coating and protection layers 5 in a shape in plan and dimensions in plan identical to the final ones of the panel.

The inventive teachings of the present invention emerge clearly from the foregoing.

In the first place, an improved embodiment of sealing and stiffening edges of a panel is proposed, at least with reference to the load resistance along one of the dimensional extensions of the panel. The provision of a reinforced sealing edge and which in addition has a reinforcement element which mechanically connects to the wood layer of the panel allows to obtain a composite sealing and stiffening edge but which has a compact structure. Furthermore, it allows to use molding processes for the realization of the sealing edge which contribute to improve the compactness and the structural resistance of the edge while using soft plastic material for the sealing. The provision of a particular orientation of the wood fibers with reference to the longitudinal axis of the strips that make up one or more layers of the wooden slab and the fact that this orientation is common to all the strips and that the strips are oriented with their axes parallel to each other in all the foreseen layers allows, in combination with the provision of the reinforced sealing edge in which at least one stiffening strip is incorporated, to increase the strength of the panel with the same thickness in the direction of the length and to have a similar load resistance in the direction of the width of the panel and to limit the need for a protective coating in particular against the infiltration of humidity to the edges oriented in the direction of the width of the panel only.

Furthermore, the realization of the corner areas of the panel with inserts of soft plastic material fixed not only by adhesion but also by at least partial shape coupling allows to limit the damage to the panels precisely in the most delicate areas and to integrate the realization of these areas corner of plastic material with the presence of reinforced sealing edges or not.

Claims (58)

CLAIMS 1. Panel for the construction of containment walls of formwork for concrete casting, in particular for containment formwork for the construction of concrete slabs or the like, which panel is formed by at least one layer of wood or the like, characterized by the fact that at least one edge of the panel is oriented at least for a part of it in a direction transverse to the direction of the wood fibers and has at least for said part a sealing edge (4) which is of plastic material, overlaps the head side of the panel along at least said part of said edge and is fixed to said head side (101) of the panel by means of chemical / physical adhesion, sealing it towards the outside. 2. Panel according to claim 1, characterized by the fact that said sealing edge (4) is provided in combination with a stiffening profile (3) or constitutes itself a stiffening element in combination with a reinforcement profile. 3. Panel according to claims 1 or 2, characterized in that it comprises a wood layer (1) with at least one end wall of a perimeter edge of said wood layer, to which the end wall is fixed, by mechanical coupling or in shape, a stiffening profile (3), which stiffening profile (3) protrudes, at least for part of its length, outwards from said head side of the edge of said layer of wood (1) being embedded in an edge sealing edge (4) of plastic material which overlaps the said head side (101) of said edge of the wood layer (1), said sealing edge (4) being coupled by chemical-physical adhesion to the head side (101) of the edge of the wood layer (1) and to the protruding portions (303, 203) of the said stiffening profile (3) in the direction of the thickness of the sealing edge (4). 4. Panel according to one or more of the claims, characterized in that the mechanical coupling between the wood layer and the stiffening profile is achieved by providing a stiffening profile with a central section (303) in the form of a strip and with an enlarged end part (103) along one of the two longitudinal edges, while in the thickness of the wood layer (1) along the said head side (101) of the said edge there is a groove (2) of a shape corresponding to the section of part of the strip (303 ) and of said enlarged end part (103), which groove (2) is open at least in correspondence with one of its head ends and being said stiffening section (3) engageable in said groove (2) through said open head side , while the strip (303) of the stiffening profile (3) protrudes for a certain length outside the head side (101) of the said edge of the said layer of wood (1). 5. Panel according to one or more of the preceding claims, characterized in that the sealing edge (4) overlaps the entire thickness of the head side (101) along the edge of the panel to which the stiffening profile (3) is associated ) and also to the entire protrusion of the stiffening section (3) itself beyond the said head side (101) of said edge of the wood layer (1). 6. Panel according to one or more of the preceding claims, characterized in that the stiffening profile (3) is made of plastic material, preferably of plastic material having a chemical nature identical or similar to that of the sealing edge (4) or a plastic material in any case chemically compatible with that of the sealing edge (4) and / or also of metallic material. 7. Panel according to one or more of the preceding claims, characterized in that the protruding part of the stiffening profile (3) is provided with a surface treatment to roughen or increase the adhesiveness. 8. Panel according to one or more of the preceding claims, characterized in that the surface treatment can be a mechanical treatment, for example the provision of scoring or knurling in the surface of the stiffening profile (3) and / or a chemical or physical treatment that changes the physical or chemical conditions from the surface layer of the stiffening profile. 9. Panel according to one or more of the preceding claims, characterized in that the edge (203) of the protruding part of the stiffening profile (3) can also be made widened with respect to the thickness of the flat part (303), similarly to the widening (103) inserted in the groove (2) provided in the edge of the wood layer (1). 10. Panel according to one or more of the preceding claims, characterized in that the sections of the enlargements (103, 203) are the same or different from each other. 11. Panel according to one or more of the preceding claims, characterized in that the stiffening profile has a double T or H-shaped section. 12. Panel according to one or more of the preceding claims, characterized in that the wood layer is composed of several layers (1A, 1B) of strips (6) or of wood material or the like, joined together and forming the layer wooden panel (1). 13. Panel according to one or more of the preceding claims, characterized in that a first layer (1A) is formed by a plurality of side by side wooden strips (6) joined together along the end sides of mutual contact of the longitudinal edges (106 ) of said strips (6) and said first layer (1A) is coupled to a further layer (1B) or to several layers of wood fibers which in turn can be in the form of a single or multilayer sheet, plywood and / or of chipboard or similar. 14. Panel according to claim 13, characterized in that at least one further layer (1B) is fixed to the first layer of strips, directly or with the interposition of further layers of wood fibers of a different type and structure. of wooden strips (6) arranged side by side and joined together along the longitudinal sides of mutual contact of the longitudinal edges (106) of said strips. 15. Panel according to claim 14, characterized in that the at least two layers (1A, 1B) of strips (6) are arranged relative to each other with the longitudinal axes of the strips (6) oriented in different directions, i.e. crossed each other. 16. Panel according to claims 14 or 15, characterized by the fact that the wood layer is formed by at least one layer formed in turn by a plurality of side by side wooden strips joined together along the longitudinal sides of mutual contact of the longitudinal edges (106 ) of said strips, the wood fibers of the individual strips (6) being oriented in the longitudinal direction of the strips (6) themselves. 17. Panel according to claim 16, characterized in that it comprises two or more layers (1A, 1B) of overlapping strips (6), each of which has a longitudinal extension or a longitudinal axis (L) oriented in the direction of the fibers or wood grain. 18. Panel according to one or more of the preceding claims, characterized in that the sealing edge (4) can be made of plastic, soft plastic or relatively soft and elastic material such as soft polyurethane. 19. Panel according to one or more of the preceding claims, characterized in that the application of the sealing edge preferably takes place by overmoulding and in particular by injection of plastic material on the perimeter application edge of the sealing edge (4) which it is provided or not with the stiffening profile or strip (3) held in the predetermined final operative position. 20. Panel according to claim 19, characterized in that it has chambers, interstices or slots filled with plastic material by injection between the internal delimiting surface of the groove (2) and the external surface of the stiffening profile (3), i.e. of the parts (103, 303) inserted into the groove (2). 21. Panel according to claim 20, characterized in that the shape of the section and / or the dimensions of the shape of the section of the groove (2) is different, in particular greater, for its entire section and / or only in correspondence with some predetermined areas with respect to the shape of the section and / or the dimensions of the said section shape of the part (203, 303) of the stiffening section (3). 22. Panel according to one or more of the preceding claims, characterized in that the wood layer (1) is formed by a plurality of wood strips (6) placed side by side and superimposed on at least two layers (1A, 1B) of side by side wooden strips (6), all the strips being oriented with their longitudinal axes parallel to each other and parallel to the longitudinal extension (L) of the panel and being the transversal sides of the panel, i.e. those oriented in the direction of the width of the panel formed by the sides of head of the wooden strips provided in correspondence with said transversal sides of the panel, while the said head sides of the strips (6) are oriented transversely to the wood fibers or to the wood grain of the wooden strips (6). 23. Panel according to one or more of the preceding claims, characterized in that it has on one or both faces of the wood layer (1) one or more external cladding layers (5) having a moisture barrier function, as well as anti-adhesion for concrete. 24. Panel according to claim 23, characterized in that said coating layers (5) consist of thin films of resins, paints, or the like or of layers of plastic material, for example of the type consisting of polypropylene decayed with vegetable flours and known for example as Wood-Stock ®. 25. Panel according to claim 24, characterized by the fact that said coating or protection layers (5) are joined together in a tight way by means of chemical / physical adhesion to the sealing edges (4), thus generating a sealing jacket of the internal wood layer (1) which sealing jacket is of plastic or resin material and is sealed on all sides or at least on the transverse sides and on the two faces of the panel, by means of said chemical / physical adhesion, for example welding, gluing or the like . 26. Panel according to claim 25, characterized in that the sealing edge (4) overlaps the thickness of the wood layer (1) and also the thickness of the covering or protective layer (s) (5) with which it is connected tight. 27. Panel according to one or more of the preceding claims, in which at least one further layer (1B) is fixed to a first layer (1A) of wooden strips (6) in superimposed position, directly or with the interposition of further intermediate layers of wooden strips (6) in which said strips are arranged side by side and joined together along the longitudinal sides of mutual contact of the longitudinal edges (106) of said strips and in which the wood fibers of the individual strips (6) are oriented in the longitudinal direction of the strips (6) themselves. 28. Panel according to claim 27, characterized in that the position of the strips of a first layer (1A) is offset transversely with respect to the position of the strips (6) of at least a second layer (1B) superimposed on the first in such a way, to wherein the longitudinal surfaces (106) of mutual contact and union of the strips (6) of said first layer (1A) fall into a position that does not coincide with the longitudinal surfaces (106) of mutual contact and union of the strips (6) of said second layer (1B) to each other, ie in a position coinciding with an intermediate longitudinal axis of the strips (6) of said second layer (1B) and vice versa. 29. Panel according to claim 28, characterized in that in the transversal direction of the strips the resistance to deformation or transverse warping of the panel is determined by the presence of the sealing edges (4) reinforced by at least one stiffening profile (3) at least along the two leading edges of the panel oriented transversely to the longitudinal axis of the strips and / or to the orientation of the wood fibers. 30. Panel according to one or more of the preceding claims, characterized in that it has at least two or more layers of wood fibers and in particular two or more layers (1A, 1B) overlapping each one formed by strips (6) side by side and joined together along the longitudinal sides (106) of mutual contact being provided only one stiffening strip (3) for each leading edge of the panel or a stiffening strip for each layer (1A, 1B) of wood or for a subset of layers with respect to the global number of layers. 31. Panel according to claim 30, characterized that the groove (2) for inserting the stiffening profile (3) is made within the thickness of one layer (1A, 1B) extends or can extend over the thickness of several adjacent layers (1A, 1B). 32. Panel for the construction of containment walls of formwork for concrete casting, in particular for containment formwork for the construction of concrete slabs or the like, which panel is formed by at least one layer of wood or the like, characterized from the fact that the wood layer (1) has recessed corner areas (7) which are filled with plastic inserts (8) with a shape that completes the perimeter shape of the panel to an ideal shape provided for it in the absence of said re-entrant areas 33. Panel according to claim 32, characterized in that the recesses (7) in correspondence with the corner areas of the panel are provided with a curved wall (107) in the shape of a C or U which opens towards the edge on the transverse side of the panel. 34. Panel according to claims 32 or 33, characterized in that it has a sealing edge (4) which sealing edge (4) is connected to one or more filling inserts (8) of plastic material of at least one or more of said recesses (7). 35. Panel according to one or more of claims 32 to 34, characterized in that said sealing edge (4) joins together the filling inserts (8) of two recesses (7) in correspondence of the corner areas to the two ends of said transverse edge of the panel. 36. Panel according to claims 34 or 35, characterized in that the sealing edge (4) is made reinforced and the reinforcement element (3) also extends into the recesses (7) of the corner areas being incorporated into the material plastic of the corresponding filling insert (8) and along at least part of the sealing edge (4). 37. Panel according to claim 36, characterized by the fact that the reinforcement element consists of a stiffening profile (3) which is inserted in a groove (2) along an edge, preferably in the transverse edges of the panel. 38. Panel according to claim 37, characterized in that said groove (2) opens with at least one or with each of its ends into a corresponding recess (7) of the corner area of the panel which recesses (7) are provided in the opposite corner zones at the ends of said transverse edge and the stiffening profile (3) is of such length as to protrude in one or both of said recesses (7) at least for a part of their extension in a direction parallel to the transverse edge of the panel. 39. Panel according to claim 37, characterized in that the end or ends of the stiffening profile (3) and which protrude into the corner recesses (7) of the panel are bent in such a way as to extend for a certain depth of the corresponding recess in the direction of the extension of the recess both parallel to the transverse edge and parallel to the longitudinal edge Panel according to one or more of claims 32 to 39, characterized in that the filling insert (8) of the recess (s) (7) and the sealing edge (s) (4) connected thereto are made in one piece and of the same material. 41. Panel for the construction of containment walls of formwork for concrete casting, in particular for containment formwork for the construction of concrete slabs or the like, which panel is formed by at least one layer of wood or the like, characterized by the fact that at least one edge of the panel is oriented at least for a part thereof in a direction transverse to the direction of the wood fibers and has at least along a part of said edge a groove (2) for interlocking engagement and / or by means of shape coupling and / or by coupling by friction and / or by coupling by force for a corresponding appendix (103, 303) for engaging a stiffening strip (3). 42. Panel according to claim 41, characterized that said stiffening strip fixed to the wood layer (1) of the panel is embedded and / or incorporated in a sealing edge of soft plastic material formed by over-molding along at least said part of edge of the panel and which adheres to the head side of said edge and to the stiffening strip. 43. Panel according to claims 41 or 42, characterized in that the stiffening profile has a cross section in the shape of a T, an H or a double T. 44. Panel according to claim 43, characterized in that the stiffening profile (3) has a T-shaped cross section, the fin (303) corresponding to the leg of the T-section intended to engage in a corresponding groove (2) in the leading edge of the wood layer. 45. Panel according to claim 44, characterized in that the flap (203) of the stiffening profile forming the crosspiece of the T-section overlaps from the outside to the head side of the edge of the wood layer (1) to to which the profile (3) is fixed and covers it for at least part of the thickness or entirely towards the outside. 46. Panel according to one or more of the preceding claims 41 to 45, characterized in that it has one or more of the characteristics of one or more of the claims 1 to 40. 47. Process for the manufacture of a panel for the construction of formwork containment walls for concrete casting, in particular for containment formwork for the construction of concrete slabs or the like, which panel is formed by at least one layer made of wood or the like, characterized in that it provides for the production by over-injection molding of a sealing edge (4) along at least one perimeter edge of the ob-layer of wood of the panel. 48. Process according to claim 47, characterized in that it provides for the incorporation in the sealing edge (4) of a reinforcement element (3) such as a stiffening section (3), said section being held in position along the edge of the panel and the stiffening profile (3) embedded in the sealing edge and joined together with the same to the edge of the wood layer by over-injection molding of said sealing edge (4). 49. Process according to claim 48, characterized in that it provides for the creation of a recess or a groove for mechanical coupling of a stiffening profile along at least one, a part or all of the peripheral edges of the wood layer (1), the insertion of said stiffening profile into said coupling recesses and in such a position as to project a partial length into the compartment intended to be occupied by the sealing edge (4) which is generated by injection into said compartment of plastic material which incorporates the protruding part of the stiffening profile (3) and connects to the corresponding edge or to the corresponding edges of the wood layer (1). 50. Process for the manufacture of a panel for the construction of containment walls of formwork for concrete casting, in particular for containment formwork for the construction of concrete slabs or the like, which panel is formed by at least one layer made of wood or the like, characterized in that it provides for the creation of recesses (7) in the corner areas of the rectangular, square or polygonal perimeter shape of the wood layer (1) and the filling of said recesses (7) by overmoulding plastic injection. 51. Process according to claim 50, characterized in that the recesses (7) are made with at least one concave boundary wall (107). 52. Process according to claims 50 or 51, characterized in that it provides for the production along at least one peripheral edge of the wood layer (1) of a sealing edge (4) which sealing edge is made by injection over-molding , said sealing edge being made one-piece with at least one filling insert (8) of the recesses (7) during the same injection over-molding step. 53. Process according to claim 52, characterized by the fact that the sealing edge (4) is made reinforced by being incorporated in it at least one reinforcement element such as a stiffening profile, said stiffening profile (3) being of such length as to extend at least partially along the sealing edge (4) and partially also inside the filling insert (8) of the recesses (7) of the wood layer. 54. Method according to claim 53, characterized in that the stiffening profile (3) is mechanically engaged in advance with the corresponding edge of the wood layer (1), while the sealing edge (4) and the filling insert (s) (8) are molded by injection over said edge and in said recesses of the wood layer and on the stiffening profile. 55. Process according to one or more of claims 47 to 54, characterized in that at least one covering and / or protective layer (5) of one face thereof is applied to the wood layer (1) by means of chemical / physical adhesion , since the sealing edge (4) and / or the inserts (8) for filling the recesses applied to the panel already provided with the wood layer and said at least one covering or protection layer (5) on at least one side, in such that during molding the material forming the sealing edge (4) and / or the filling insert (8) overlaps the head surface (101) of the edge of the wood panel and the corresponding thickness of the edge of the covering and / or protection layer (5). 56. Process for manufacturing a panel for the construction of formwork containment walls for concrete casting, in particular for containment formwork for the construction of concrete slabs or the like, which panel is formed by at least one layer made of wood or the like, characterized in that the wood layer 1 is formed by fixing a plurality of side-by-side wooden strips (6) to each other along facing longitudinal sides (106) so as to form a slab or the like , said strips being made with their longitudinal axis parallel to the direction of the wood fibers or joints. 57. Process according to claim 1, characterized in that it provides for the superposition of two layers of wood (1A, 1B) and the fixing of said layers to each other, each layer being formed by a plurality of side by side wooden strips (6). 'one to the other along longitudinal sides (106) facing each other so as to form a slab or the like and the said strips being made with their longitudinal axis parallel to the direction of the fibers or joints of the wood while the strips (6) of the two layers they are positioned with their longitudinal axes parallel to each other and with the adhesion surfaces (106) of the strips side by side with each other in a laterally offset position on each layer (1a, 1B). 58. Process according to claims 56 or 57, characterized in that it comprises one or more of the steps of claims 47 to 55.