Abstract:
The invention relates to a wood-reinforced structure comprising several beams ( 2, 3, 4, 6, 7 ) which are constructed from at least three wood boards ( 16, 17, 18 ), two external boards ( 16, 17 ) and a central board ( 18, 19, 21, 22 ), said boards being assembled to one another. The aforementioned external boards ( 16, 17 ) are positioned on either side of the central board ( 18 ) and said central board is positioned at the junction zones which form an intersection ( 8, 9, 11, 12, 13 ) between at least two beams ( 2, 3, 4, 6, 7 ). The central wood board ( 18, 19, 21, 22 ) is inserted fully into the housing ( 23, 24, 26 ) which is disposed in each of the two external wood boards ( 16, 17 ).

Description:
[0001]    The present invention relates to a reinforced wooden structure. The present invention also relates to a framework equipped with a reinforced wooden structure. The present invention is concerned with a building having a framework equipped with a reinforced wooden structure. The present invention additionally relates to a method for manufacturing and assembling a reinforced wooden structure.  
           [0002]    Wood is a material which is very widely used in construction, and with which it is possible to produce a whole series of load-bearing systems having their own specific mechanical properties and capable of withstanding all levels and types of load. The various load-bearing systems made of wood are, for the main part, posts and beams, triangulated systems also referred to as “trusses”, jointed systems, portal frames, beam latticeworks, shells and elements operating as plates.  
           [0003]    The invention relates to the production of a reinforced wooden structure with parallel members or in the form of a truss, which has good mechanical properties, allows a reduction in the production costs and can be readily adapted to suit the characteristics desired for each specific application (load to be withstood, dimensions of the structure, etc.).  
         PRIOR ART  
         [0004]    A great many proposals have been made with respect to producing the assembly node forming an intersection between at least two beams of the triangulated wooden systems, whether these be systems with parallel members or-triangular systems.  
           [0005]    Documents CH 467,402 and FR 2,303,128 disclose a reinforcement placed in beams which are formed as one piece at the intersection node. The reinforcement is inserted into a simple slot made for its passage. Metal fittings are also provided to keep the assembly in place.  
           [0006]    However, these solid timbers of large cross section are relatively expensive. The problems associated with solid timbers are also deformations and cracks which appear with drying, which is made more difficult when the cross sections increase. This type of wood is generally employed in the nondried state.  
           [0007]    Document WO 00/32,891 discloses an economic way of producing beams using structures formed by planks nailed together to make up larger cross sections from wood of small cross section. A reinforced wooden structure is formed by several beams constructed from at least three planks. The two outer planks and the central plank are joined to one another, the two outer planks being placed on either side of the central plank. In addition to the central planks, reinforcements are positioned at the junction zones forming an intersection between at least two beams.  
           [0008]    A first disadvantage of these reinforced structures is the presence of a given odd number of planks, which gives successive incrementations of thicknesses lacking flexibility. Another disadvantage is that the central planks and the reinforcements must constantly keep the same thickness for one and the same structure. Another disadvantage is that marking, positioning and fixing the various reinforcements and central planks prove to be relatively complex and inexact operations, since this involves longitudinal joining without blocking points. Another disadvantage is that central planks and reinforcements give a large number of components for one and the same truss, which gives rise to high manufacturing costs and increased assembly times.  
           [0009]    Documents DE 100 50 989 and U.S. Pat. No. 4,891,927 disclose a reinforcement of the beam intersection node using a central metal piece which is completely embedded in an indentation formed symmetrically between two wooden planks situated on either side. This central metal piece is provided with integral nails or pins which are driven into each of the two planks from the piece itself.  
           [0010]    This solution is not entirely satisfactory owing to the fact that the strength of the intersection node depends on the cross section of the wooden planks situated on either side of the central metal piece. The central metal piece is thus unable to reinforce the assembly node, but only able to transmit forces through the integral nails or pins. Such a solution is very expensive because it requires force-fitting the central metal piece at the factory. This solution thus rules out the possibility of assembly by skilled workers at the actual site, and does not allow easy adaptation to suit the constructions to be produced. Moreover, the integral nails or pins must be welded perfectly to the central metal piece so that the wooden planks situated on either side assume a well-aligned position. Finally, and as yet another disadvantage, the central metal pieces conduct high temperatures and lose their rigidity in the event of fire.  
         SUMMARY OF THE INVENTION  
         [0011]    One of the main problems posed is that of being able to absorb the maximum flow of force which is localized at the supports, the intersections and the diagonals so as to simultaneously take up bending, tensile, compressive and shear forces. A second problem is to succeed in reducing the number of components in the case of one and the same reinforced wooden structure. A third problem is to provide a way of marking, positioning and automatically fixing the various central planks. A fourth problem is of developing a method of manufacturing reinforced structures which allows the possibility of assembly by skilled workers on the actual site and can be easily adapted to suit the constructions to be produced.  
           [0012]    A reinforced wooden structure consists of several beams constructed from at least three wooden planks, two outer planks and one central plank, which are joined to one another, the two outer planks being placed on either side of the central plank, the central plank being positioned at the junction zones forming an intersection between at least two beams.  
           [0013]    According to the invention, the reinforced structure is characterized in that the central wooden plank is inserted in a housing formed by two cutouts, each made in one of the two outer wooden planks.  
           [0014]    Thus, in such a structure, the means of connection used, which are totally independent of the two outer planks and the central plank, will work in shear with the two planks. In order to avoid any asymmetry, the housing may preferably be formed symmetrically in the two outer planks, such that the two cutouts have the same depth. The width of the central wooden plank may be greater than or equal to the width of the two outer wooden planks so as to further increase the contact areas and thus the reinforcing effect.  
           [0015]    In a particularly favorable manner, the beams of the reinforced structure may comprise a number N of central wooden planks and a number N+1 of outer wooden planks. The N central planks may then be inserted in a number N of housings made in the N+1 outer planks. In another exemplary embodiment, the beams may further comprise two additional wooden planks arranged on each of the visible faces of the two outermost wooden planks.  
           [0016]    In yet another exemplary embodiment, the beams may comprise a first group having a number N of central planks and a number N+1 of outer planks which is joined to a second group having a number N of central planks and a number N+1 of outer planks. The N central planks may be inserted in N housings made in the N+1 outer planks.  
           [0017]    In an advantageous manner, the central plank or planks may have a thickness which is different than that of the outer planks. The material of the central plank or planks may be selected, individually or in combination, from the group consisting of Kertopuu® panels and other glued microlam panels with high mechanical performance.  
           [0018]    According to a second aspect of the invention, a framework is characterized in that it is equipped with a reinforced wooden structure as described above.  
           [0019]    According to a third aspect of the invention, a building is characterized in that it comprises a framework as described above.  
           [0020]    According to a fourth aspect of the invention, a method for manufacturing and assembling the reinforced wooden structure as described above is characterized in that it comprises the steps consisting in making a cutout in each of the two outer wooden planks at the junction zones forming an intersection between at least two beams, in positioning a central wooden plank in the cutout, and in assembling the two outer wooden planks and the central wooden plank.  
           [0021]    The reinforced wooden structure may preferably be assembled by nailing, screwing, pinning and/or by gluing. 
       
    
    
     DESCRIPTION OF THE DRAWINGS  
       [0022]    A good understanding of the invention will be provided, and its various advantages and characteristics will emerge more clearly, from the subsequent description of the nonlimiting exemplary embodiment with reference to the appended schematic drawings, in which:  
         [0023]    [0023]FIG. 1 represents a side view of a truss;  
         [0024]    [0024]FIG. 2 represents a perspective exploded view of a three-plank truss;  
         [0025]    [0025]FIG. 3 represents a perspective exploded view of a five-plank truss;  
         [0026]    [0026]FIG. 4 represents a view in longitudinal section of a three-plank beam;  
         [0027]    [0027]FIG. 5 represents a view in longitudinal section of a five-plank beam;  
         [0028]    [0028]FIG. 6 represents a view in longitudinal section of a seven-plank beam;  
         [0029]    [0029]FIG. 7 represents a view in longitudinal section of a five-plank beam, in an alternative embodiment;  
         [0030]    [0030]FIG. 8 represents a view in longitudinal section of a seven-plank beam, in an alternative embodiment;  
         [0031]    [0031]FIG. 9 represents a view in longitudinal section of a six-plank beam, in an alternative embodiment;  
         [0032]    [0032]FIG. 10 represents a side view of a truss with simple beams;  
         [0033]    [0033]FIG. 11 represents a side view of a two-pinned portal frame;  
         [0034]    [0034]FIG. 12 represents a side view of a latticework with parallel members;  
         [0035]    [0035]FIG. 13 represents a side view of a half-truss;  
         [0036]    [0036]FIG. 14 represents a side view of a truncated truss;  
         [0037]    [0037]FIG. 15 represents a side view of a truss with upturned ties;  
         [0038]    [0038]FIG. 16 represents a side view of a three-pinned portal frame; and  
         [0039]    [0039]FIG. 17 represents a side view of a multi-facet truss. 
     
    
     DETAILED DESCRIPTION  
       [0040]    The primary reinforced structures in the form of a triangle ( 1 ), or “truss” (see FIGS.  1  to  3  and  10  to  17 ), are generally used to produce roof frameworks and provide the roof with its pitch. The elements involved in the production of such structures are composed of two principal rafters ( 2 ), of a tie ( 3 ), of two diagonals ( 4 ), of a post ( 6 ) and of two angle braces ( 7 ). Such assemblies rest on supports (not shown) arranged at each end of the tie ( 3 ).  
         [0041]    The various elements, that is to say the principal rafters ( 2 ), the tie ( 3 ), the two diagonals ( 4 ), the post ( 6 ), and the two angle braces ( 7 ) are in beam form and are denoted in the remainder of the description by the common term “beam”. Each beam is constructed from planks which are nailed to one another to make up larger cross sections.  
         [0042]    There are thus a node or intersection ( 8 ) between principal rafters ( 2 ) and tie ( 3 ), an intersection ( 9 ) between principle rafters ( 2 ) and post ( 6 ), an intersection ( 11 ) between principal rafters ( 2 ) and diagonals ( 4 ), an intersection ( 12 ) between principal rafters ( 2 ) and angle braces ( 7 ), an intersection ( 13 ) between tie ( 3 ) and angle braces ( 7 ) and an intersection ( 14 ) between tie ( 3 ), diagonals ( 4 ), and post ( 6 ).  
         [0043]    To produce these structures, the constituent planks involved in making up each beam are solid wooden planks whose cross section is generally between 15 cm and 30 cm wide by 3 cm to 10 cm thick, not excluding other specific dimensions. Moreover, with thin planks, for example of around 3 cm to 5 cm, it is possible carry out artificial drying under conventional conditions. The length of said planks may be variable and dependent on the structures to be produced, and will be, for example, between 4 m and 12 m. Longer planks may be obtained by finger jointing.  
         [0044]    For structures capable of having great strength, individual planks may be combined to give larger cross sections. The planks may also be in the form of glued laminated or microlaminated planks of the Kertopuu® type or other equivalents.  
         [0045]    All of the beams involved in the formation of such a structure are formed by three constituent planks ( 16 ,  17  and  18 ), for example nailed together (see FIGS. 2 and 4). The beams comprise two outer planks ( 16  and  17 ) and one central plank ( 18 ). The central plank or plate ( 18 ) constitutes a reinforcement.  
         [0046]    According to the invention, the central planks or reinforcements ( 18 ) make it possible in a simple manner to reinforce the intersections forming a junction between these beams, and more specifically make it possible for the intersections subjected to the most stress to be reinforced. The reinforcements ( 18 ) are thus positioned in the central layer, which allows the connection means or connectors passing through to be in double shear by comparison with reinforcements exposed on the outside of the structure, as is often the case.  
         [0047]    The length and width of the reinforcements ( 18 ) is independent of the length and width of the outer planks ( 16  and  17 ). The width of the reinforcements ( 18 ) is greater than or equal to the width of the two outer planks ( 16  and  17 ). Moreover, however, to increase the inertia of the reinforcements ( 18 ) and thus reinforce the assembly node, the surface area of the reinforcements ( 18 ) is enlarged so as to greatly exceed the dimensions of the node and protrude outside the structure (see FIGS.  1  to  3  and  10  to  17 ).  
         [0048]    An upper reinforcement ( 19 ) is placed at the intersection ( 9 ) between principal rafters ( 2 ) and post ( 6 ). A lateral reinforcement ( 21 ) connects the intersection ( 11 ) between principal rafters ( 2 ) and diagonals ( 4 ), the intersection ( 12 ) between principal rafters ( 2 ) and angle braces ( 7 ) to the intersection ( 13 ) between tie ( 3 ) and angle braces ( 7 ). Given that the intersections ( 11 ,  12  and  13 ) are duplicated to the left and right of one and the same truss ( 1 ), two reinforcements ( 21 ), one right and one left, are used. A lower reinforcement ( 22 ) is placed at the intersection ( 14 ) between tie ( 3 ), diagonals ( 4 ), and post ( 6 ).  
         [0049]    The lateral reinforcement ( 21 ) in the form of a plank is able to take up the bending moment and the local shear which are generated by the two internal beams, for example the compressed diagonal ( 4 ) and the compressed angle brace ( 7 ). The lateral reinforcement ( 21 ) thus reinforces the intersection ( 11 ) with respect to bending and to local shear forces which are important mechanical components of the system of intersection. The lateral reinforcement ( 21 ) acts as an additional rib. It should be noted that the lateral reinforcement ( 21 ) is offset with respect to the node ( 8 ) between the principal rafter (2) and tie ( 3 ).  
         [0050]    According to the invention, the various reinforcements ( 19 ,  21  and  22 ) are inserted in housings. These housings are each formed by two cutouts, each being cut into a face of each of the two outer planks ( 16  and  17 ). The combination of two cutouts constitutes a housing. The length of the housings is independent of the length of the outer planks ( 16  and  17 ).  
         [0051]    These cutouts have a depth which is substantially equal to half the thickness of the various reinforcements ( 19 ,  21  and  22 ). By virtue of this characteristic, it is thus no longer necessary for the three constituent planks ( 16 ,  17  and  18 ) forming each beam to be of the same thickness.  
         [0052]    Housings ( 23 ) are thus provided at the upper end of the principal rafters ( 2 ) and of the post ( 6 ) in the region of the intersection ( 9 ). These housings ( 23 ) are intended for the upper reinforcement ( 19 ). Housings ( 24 ) are thus provided over a portion of the length of the principal rafters ( 2 ), at the upper end of the diagonals ( 4 ), over the whole length of the angle braces ( 7 ) and over part of the tie ( 3 ), in the region of the intersections ( 11 ,  12  and  13 ). The angle braces ( 7 ) will simply have a thickness which is less than that of the planks ( 16  and  17 ). These housings ( 24 ) are intended for the lateral reinforcements ( 21 ). Housings ( 26 ) are thus provided at the lower end of the diagonals ( 4 ), at the lower end of the post ( 6 ) and at the center of the tie ( 3 ), in the region of the intersection ( 14 ). These housings ( 26 ) are intended for the lower reinforcement ( 22 ).  
         [0053]    The reinforcements ( 19 ,  21  and  22 ) and their positioning by embedding are always calculated to take up the shear forces generated by the two diagonals ( 4 ) occurring at the intersection, to take up the tensile forces and compressive forces in the axis of the diagonals ( 4 ) and to reinforce the principal rafters ( 2 ) in the region of the intersections so as to simultaneously take up bending forces and local compressive forces. These reinforcements ( 19 ,  21  and  22 ) of the “plate” type have great rigidity and work in both directions of the plane. However, in certain cases, the reinforcements have a main direction for absorbing forces and they may be reoriented differently in relation to the plank for better efficiency.  
         [0054]    In the manufacturing method, the cutouts corresponding to the housings ( 23 ,  24  and  26 ) are produced automatically, for example by numerical machining of the planks ( 16  and  17 ). The planks ( 16  and  17 ) are thus always planed. An antifungal treatment and a wood stain may be applied during machining.  
         [0055]    During assembly, the cutouts forming the housings ( 23 ,  24  and  26 ) in the planks ( 16  and  17 ) allows automatic positioning, without any marking, of the reinforcements ( 19 ,  21  and  22 ) without having to mark out the positions of the latter, unlike in the prior art. This constitutes an appreciable saving in time and precision in terms of assembly and reliability of the reinforced structure. The production plant can deliver complete trusses with all the components cut and numbered, which a skilled worker can then assemble by himself at his worksite.  
         [0056]    The various planks ( 16  and  17 ) and reinforcements ( 19 ,  21  and  22 ) are connected using independent connectors, by nailing, screwing or pinning. The connectors will pass right through the first plank ( 16  or  17 ), right through the reinforcement ( 18 ,  21  or  22 ) and about four-fifths of the way through the second plank ( 17  or  16 ). Such a solution allows greater forces to be withstood, the reinforcements ( 19 ,  21  and  22 ) in the region of the intersection zones ( 9 ,  11 ,  12 ,  13  and  14 ) increasing the nailing zones. Moreover, since the timbers are nailed in the dry state, there is no longer any deformation of the composite cross section. This nailing operation is designed not to crack the central reinforcements ( 19 ,  21  and  22 ).  
         [0057]    From a mechanical and structural performance point of view, the positioning of the reinforcements ( 19 ,  21  and  22 ) inside the housings ( 23 ,  24  and  26 ) is favorable for the transmission of forces. It is possible to make savings on connection means, such as nails, screws, bolts, etc. Furthermore, because the reinforcements ( 19 ,  21  and  22 ) are pre-fixed by fitting, it is conceivable for them to be glued at the bottom of the cutouts forming the housings ( 23 ,  24  and  26 ). This gluing of the reinforcements ( 19 ,  21  and  22 ) may be sufficient to assemble and produce the entire wooden structure. These central reinforcements ( 19 ,  21  and  22 ) in the form of planks therefore have good performance at their points of assembly.  
         [0058]    The reinforcements ( 19 ,  21  and  22 ) have a thickness which is conventionally between 27 mm and 39 mm. Thus, the corresponding cutouts of the housings ( 23 ,  24  and  26 ) will have a depth between 13.5 mm and 19.5 mm, respectively.  
         [0059]    These reinforcements ( 19 ,  21  and  22 ) are produced from a panel consisting of a structural element of LVL wood of the microlaminated plywood type. This is a laminated wood made up of spruce veneers which are obtained by rotary cutting. These approximately 3 mm-thick veneers are hot-glued, grain on grain, under high pressure with a weather-resistant phenolic resin. The fibers are arranged in the longitudinal direction. This plywood is marketed for example by Finnforest under the name Kertopuu® or Kerto®. Other glued microlam or plywood panels with high mechanical performance can also be used.  
         [0060]    In an alternative embodiment (see FIGS. 3 and 5), starting from a structure with beams comprising three constituent planks, it may also be envisioned to produce beams with five planks. All of the beams ( 2 ,  3 ,  4 ,  6  and  7 ) involved in the configuration of a reinforced structure of the truss type are formed by five constituent planks ( 27 ,  28 ,  29 ,  31  and  32 ), for example nailed together.  
         [0061]    In this variant, the term “outer plank” applies to all the planks ( 27 ,  29 , and  32 ) which are not reinforcements, even though they are included within the reinforced structure. The same technical characteristics of the reinforcements and planks already described above for the truss having beams comprising three planks will be adopted, with two upper reinforcements ( 19 ), four lateral reinforcements ( 21 ) and two lower reinforcements ( 22 ).  
         [0062]    The reinforcements ( 28  and  31 ) are thus duplicated and are then respectively positioned between the first plank ( 27 ) and the second plank ( 29 ) and between the second plank ( 29 ) and the third plank ( 32 ). The plank inserted at the center ( 29 ) will be machined on its two faces to form the cutouts required for positioning the reinforcements ( 28  and  31 ).  
         [0063]    In an alternative embodiment (see FIG. 6), starting from a structure having beams comprising five constituent planks, it may also be envisioned to produce beams having seven planks. All of the beams ( 2 ,  3 ,  4 ,  6  and  7 ) involved in the configuration of a reinforced structure of the truss type are formed by seven constituent planks ( 33 ,  34 ,  36 ,  37 ,  38 ,  39  and  41 ), for example nailed together.  
         [0064]    In this variant, the term “outer plank” applies to all the planks ( 33 ,  36 ,  39  and  41 ) which are not reinforcements, even though they are included within the reinforced structure. The same technical characteristics of the reinforcements and planks already described for the truss having beams comprising three or five planks will be adopted, with three upper reinforcements ( 19 ), six lateral reinforcements ( 21 ) and three lower reinforcements ( 22 ).  
         [0065]    The reinforcements ( 34 ,  37  and  39 ) are thus tripled and are then respectively positioned between the first plank ( 33 ) and the second plank ( 36 ), between the second plank ( 36 ) and the third plank ( 38 ) and between the third plank ( 38 ) and the fourth plank ( 41 ). The planks inserted at the center ( 36  and  38 ) will be machined on their two faces to form the cutouts required for positioning the reinforcements ( 34 ,  37  and  39 ).  
         [0066]    If the invention is extrapolated, the structure is characterized in that the number within the planks of reinforcements being positioned at each intersection is equal to N, the number of outer planks being equal to N+1. Given that the N planks of reinforcements are inserted in the N+1 outer planks, the total thickness of the beams will be equal to the sum of the thicknesses of the N+1 outer planks. Each connector will work with two, four or even six shear sections. This is advantageous in the case of large frameworks intended for agricultural or industrial buildings having free spans of 40 m to 60 m.  
         [0067]    In an alternative embodiment (see FIG. 7), starting from a structure having beams comprising three constituent planks ( 16 ,  17  and  18 ) (according to FIG. 4), it may also be envisioned to produce beams having five planks. All the beams ( 2 ,  3 ,  4 ,  6  and  7 ) involved in the configuration of a reinforced structure of the truss type are formed by five constituent planks ( 16 ,  17 ,  18 ,  42  and  43 ), for example nailed together. The two planks ( 42  and  43 ) are fixed to the respective free visible outer face of the two outermost planks ( 16  and  17 ).  
         [0068]    In this variant, the term “outer plank” applies to all the planks ( 16  and  17 ) which are not reinforcements ( 18 ), even though they are included within the reinforced structure. The same technical characteristics of the reinforcements and planks already described above for the truss having beams comprising three planks will be adopted, with an upper reinforcement ( 19 ), two lateral reinforcements ( 21 ) and a lower reinforcement ( 22 ).  
         [0069]    In another alternative embodiment (see FIG. 8), starting from a structure having beams comprising five constituent planks ( 27 ,  28 ,  29 ,  31  and  32 ) (according to FIG. 5), it may also be envisioned to produce beams having seven planks. All the beams ( 2 ,  3 ,  4 ,  6  and  7 ) involved in the configuration of a reinforced structure of the truss type are formed by seven constituent planks ( 27 ,  28 ,  29 ,  31 ,  32 ,  42  and  43 ), for example nailed together. The two planks ( 42  and  43 ) are fixed to the respective free visible outer face of the two outermost planks ( 27  and  32 ).  
         [0070]    In this variant, the term “outer plank” applies to all the planks ( 27 ,  29  and  32 ) which are not reinforcements ( 28  and  31 ), even though they are included within the reinforced structure. The same technical characteristics of the reinforcements and planks already described above for the truss having beams comprising three or five planks will be adopted, with two upper reinforcements ( 19 ), four lateral reinforcements ( 21 ) and two lower reinforcements ( 22 ).  
         [0071]    In an alternative embodiment (see FIG. 9) starting from a structure having beams comprising three constituent planks ( 16 ,  17  and  18 ) (according to FIG. 4), it may also be envisioned to produce beams having six planks. All the beams ( 2 ,  3 ,  4 ,  6  and  7 ) involved in the configuration of a reinforced structure of the truss type are formed by six constituent planks ( 16   a ,  17   a ,  18   a ,  16   b ,  17   b  and  18   b ), for example nailed together. This is in fact a first substructure or group comprising three constituent planks ( 16   a ,  17   a , and  18   a ) which is joined to a second substructure or group comprising three constituent planks ( 16   b ,  17   b  and  18   b ).  
         [0072]    In this variant, the term “outer plank” applies to all the planks ( 16   a ,  16   b ,  17   a  and  17   b ) which are not reinforcements ( 18   a  and  18   b ), even though they are included within the reinforced structure. The same technical characteristics of the reinforcements and planks already described above for the truss having beams comprising three or five planks will be adopted, with two upper reinforcements ( 19 ), four lateral reinforcements ( 21 ) and two lower reinforcements ( 22 ).  
         [0073]    For reasons of structural efficiency, a truss seen in cross section must always be symmetrical with respect to the axis of the centermost plank, that is to say, depending on the particular case, the reinforcement or the central plank which is not a reinforcement. In the case of more than-one reinforcement, the reinforcements will in principle have the same thickness. In the case of an odd number of reinforcements, the central reinforcement could have one thickness and the lateral reinforcements taken in pairs could have another thickness. This symmetry makes it possible to avoid unwanted forces, such as twisting forces on the truss, which would cause the truss to buckle on its more rigid side.  
         [0074]    The reinforcement of the intersections and of the wooden structure according to the present invention can be tailored equally well to the two broad families of triangulated wooden structures known as “structures with parallel members” and “triangulated trusses”. The structure with parallel members is used for example for bridges or horizontal floor structures.  
         [0075]    These possible structures are a truss with simple beams (see FIG. 10), a two-pinned portal frame (see FIG. 11), a latticework with parallel members (see FIG. 12), a half-truss (see FIG. 13), a truncated truss (see FIG. 14), a truss with upturned ties (see FIG. 15), a three-pinned portal frame (see FIG. 16), and a multi-facet truss (see FIG. 17).  
         [0076]    They comprise a structure substantially related to the truss ( 1 ) described in detail above. Where appropriate, they are placed on two vertical pillars ( 44 ). They comprise as many upper reinforcements ( 19 ), lateral reinforcements ( 21 ) and lower reinforcements ( 22 ) as there are possibilities of intersections and assembly nodes between the constituent beams ( 2 ,  3 ,  4  and  6 ).  
         [0077]    The present invention is not restricted to the embodiments described and illustrated. Many modifications may be made without thereby departing from the confines defined by the scope of the set of claims.