FR2892735A1 - REINFORCED LATTICE STRUCTURE AND REINFORCEMENT METHOD - Google Patents

Abstract

A trellis structure (1) comprising an elongate structural member (2) and a reinforcing device for relieving the elongate structural member of a portion of the stresses to which it is subjected, wherein the reinforcing device comprises a material for distributing the forces defining a block (4) applying on two substantially opposite faces (2a, 2b) of the elongated structural member, said block (4) of force distribution material stress distribution material being compressed against the faces of the elongated structural element (2a, 2b)

Description

Reinforced mesh structure and reinforcement method

  The present invention relates in particular to the reinforcement of a lattice structure, which it is desired to increase the bearing capacity.

  Planar wire mesh structures designed to withstand bending stresses generally consist of two main chords, one tensioned and the other compressed, as well as uprights or diagonals, connecting the main chords to each other, and intended to resume the shearing effort. These structures are extremely effective for building civil engineering structures, by the ratio of inertia to section and lever arms. They have been widely used since the 19th century to build iron or steel including bridges, towers (Eiffel Tower), or crane arrows. The interest of lattice structures is the maximum saving of the necessary material, at the cost of greater complexity in the assemblies. Indeed, the ribs, uprights and diagonals of the lattices are generally rolled sections, in the form of angles or H, connected together by connection nodes most often bolted or riveted. These assembly nodes require intermediate parts, plates or gussets, on which are anchored the elements to be assembled. But lattice structures are often quite old, and may have degraded over time. In addition, the increase in traffic and the maximum axle weight leads to higher operating costs.

  It may therefore be necessary to reinforce these lattice structures, usually without disturbing the operation of the structure, that is to say, ensuring continuity of traffic.

  Various solutions have already been proposed for this purpose. Thus, it is known to replace a chord, by separating it at the level of the assembly nodes. But, this solution requires partially dismantling the lattice, so it is relatively complicated and requires to support it temporarily. It has also been proposed to add profiles, tie rods or bumpers. However, when these profiles, tie rods or bumpers are set apart from the intermediate pieces (plates or gussets), this solution does not strengthen the chord to its end and if it does not, this solution weakens the intermediate pieces. In order to overcome the aforementioned drawbacks, the invention proposes a lattice structure comprising an elongated structural element and a reinforcing device intended to relieve the elongated structural element of a part of the stresses to which it is subjected, in which the reinforcing device comprises a force distribution material defining a block applying on two substantially opposite sides of the elongated structural member, said block of force distribution material being compressed against said faces of the elongated structural member.

  This solution requires no welding and avoids any disassembly of existing elements. It is therefore relatively simple to implement. The transfer of effort between the elongated structural member and the distribution material is effected by friction due to the compression exerted on the distribution material. The compression exerted on the distribution material also makes it possible to increase its mechanical strength. According to another characteristic according to the invention, the structure further comprises an elongate reinforcing structural member having a free end embedded in the block of force distribution material. The transfer of force between the elongated reinforcing structural member and the distribution material is also effected by friction due to the compression exerted on the distribution material. Thus, the structure is reinforced by the elongate reinforcing structural element including in the connection zone between the elongated structural element and the elongated structural reinforcing element due to the presence of the force distribution material. According to the invention, the structure further has the following features: the structure comprises a first and a second chord, the first chord comprises the elongate structural member, and the elongated structural member is attached to the second chord away from said free end 20 embedded in the block of force distribution material. Thus, the elongate reinforcing structural member effectively reinforces the structure by acting on the two chords of the structure. According to a complementary feature according to the invention, the elongate reinforcing structural member extends in a longitudinal direction and is compressed in the longitudinal direction. Thus, the elongate reinforcing structural member provides an active reinforcement that more effectively relieves the structure. According to the invention, the structure furthermore has the following features: it furthermore comprises a reinforcement tie passing through the block of material of distribution of the stresses and resting on a support secured to the block of material of distribution of the forces to a first end, the structure comprises a first and a second chord, the first chord comprises the elongated structural member, and the reinforcing tie is attached to the second chord at a second end remote from the first end. This solution also reinforces the structure by providing an active reinforcement relieving the two members of the structure. According to another characteristic according to the invention, the structure further comprises a cable bearing at one end on a support integral with the block of material for distribution of forces, said support incorporating stiffeners in the form of ribs. The force of the cable passes into the support, then into the block of material distribution forces, before being distributed over the rest of the existing structure and in particular on the elongated structural element. According to another characteristic according to the invention, the structure further comprises a cable stretched between two anchor points and passing through a passage formed in the block of material for distribution of forces, said passage being not aligned with the two anchor points. This passage serves as a deflector and is much simpler to achieve than a conventional welded deflector to weld or bolt on the elongated structural member. It can in particular be adjusted more easily in orientation on site, to accommodate the imperfections of realization of the existing structure, and avoids the manufacture of parts according to very precise geometric dimensions. According to another characteristic according to the invention, the elongated structural element comprises a portion extending in an elongation direction between two ends between which it is not maintained and the block of force distribution material is encapsulated perpendicularly. at the elongation direction in a corset and continuously in the elongation direction, substantially between the two ends of said portion of the elongate structural member. This solution makes it possible to effectively strengthen an unsupported portion of the elongated structural element over its entire length, while allowing simplified implementation and saving of iron or steel compared to prior techniques. According to the invention, the structure further has the following features: wherein the elongate structural member extends to a free end, the structure further comprises an elongate structural member extension having two substantially opposite faces and extending to a free end disposed near the free end of the elongate structural member, wherein the block of force distribution material extends near the free end of the elongated structural member on the opposing faces of the elongated structural member against which it is compressed and near the free end of the elongate structural member extension on opposite sides of the elongated structural member extension against which it is compressed.

  This solution is particularly useful when it is necessary to substitute an elongate structural element section with a new element. It makes it possible to join two elongated structural elements with excellent transmission of forces and also makes it possible to overcome the difficulty of splicing two elongated structural elements of different sections by means of the force distribution material. In the case where there is a gap between the free end of the elongated structural member and the free end of the elongate structural member extension, the force distribution material block advantageously also extends between these two. ends.

  According to the invention, the structure furthermore has the following characteristics: where the two opposite faces of the elongate structural element are substantially parallel to each other, two compression plates substantially parallel to one another are connected by constrained compression struts. in extension, where the force distribution material block extends between the plates, and the compression tie rods pass through the force distribution material block. This solution is relatively simple to implement and provides high robustness to the structure for a moderate cost. According to a complementary feature according to the invention, the compression plates extend away from the elongated structural member. Thus, the efficiency of compression exerted by the compression plates on the block of force distribution material is improved.

  According to another characteristic according to the invention, the force distribution material consists of mortar. Since the mortar exhibits excellent strength properties when compressed, it is particularly suitable for taking up part of the stresses of the elongate structural element. According to an alternative characteristic according to the invention, the force distribution material consists of a plastic resin. The plastic resin is ideal for such an application, for its ease of implementation and its propensity to adhere to the elongated structural element. The invention further relates to a method for reinforcing a lattice structure comprising an elongated structural member and a reinforcing device for relieving the elongated structural member of a portion of the stresses to which it is subjected. According to the invention, the method comprises the following steps: a) disposing a unit block of force distribution material on two substantially opposite sides of the elongated structural element, then b) compressing said block of force distribution material against the opposite faces of the elongated structural member. According to an advantageous characteristic according to the invention, during step a), the force distribution material is disposed in a substantially fluid state to form the block, and the force distribution material is then expected to be at least partially solidified to compress the block of force distribution material in step b). According to another advantageous characteristic in accordance with the invention, the method furthermore comprises the following 35 steps: prior to step a), two substantially parallel compression plates are arranged with respect to the two opposite faces of the element. structural elongated, then the two compression plates are connected by compression tie rods, - in step b), the compressive tie rods are stretched. Other features and advantages of the present invention will emerge in the following description of nonlimiting exemplary embodiments, with reference to the appended drawings in which: FIG. 1 is an overall view of a structure conforming to FIG. FIG. 2 is a scale view of the zone of the structure marked II in FIG. 1, before reinforcement; FIG. 3 is a sectional view along line III-III in FIG. 2; FIG. 4 is a view according to FIG. 2, of a first embodiment according to the invention, FIG. 5 is a sectional view along the line marked VV in FIG. 4, FIG. 2 is a view in accordance with FIG. 2 of a second embodiment according to the invention; FIG. 7 is a sectional view along the line marked VII-VII in FIG. 6; FIG. according to FIG. 2, of a third embodiment according to the invention, FIG. 9 is a sectional view along line IX-IX in FIG. 8; FIG. 10 is a view according to FIG. 2, of a fourth embodiment according to the invention; FIG. 11 is a partial view along the arrow marked XI in FIG. 10; FIG. 12 is a sectional view along the line marked XII-XII in FIG. 10; FIG. 13 is a view in accordance with FIG. of a fifth embodiment according to the invention, - Figure 14 is a sectional view along the line marked XIV-XIV in Figure 13, - Figure 15 is a view according to Figure 2, A sixth embodiment according to the invention, - Figure 16 is a sectional view along the line marked XVI-XVI in Figure 15; - Figure 17 is a sectional view along line XVII-XVII in FIG. 15. The figures illustrate a lattice structure 20 resting on the ground via pillars 7. The structure n trellis essentially comprises a tensioned chord 6 and a compressed chord 8 between which extend uprights 18 and diagonals 17. The uprights 18 and the diagonals 17 are fixed on the chords 6, 8 by means of fixing plates or gussets 16 and rivets 19 at nodes 11, 12, 13, 14. In the rest of the description, we will focus on the reinforcement provided to the structure 1 near the node 11 by the various embodiments as illustrated in Figures 4 to 17, with respect to the unreinforced structure shown in Figures 2 and 3, but a similar reinforcement could be provided to the other nodes of the structure 1.

  In the vicinity of the node 11, the stretched chord 6 is constituted on one side by an elongated structural element, here a profile 2, extending in a longitudinal direction 10 and on the other side by a profile 15. An amount 18 comes connect to the tensioned chord 6 at the node 11. The profile 2 here has a T-shaped section comprising a vertical core and a horizontal flange. The vertical core has two vertical faces 2a, 2b and substantially parallel to each other.

  In the embodiment illustrated in FIGS. 4 and 5, the structure 1 is reinforced by a reinforcing device comprising two reinforcing profiles 22, a block 4 of force distribution material and a compression assembly 26.

  The block 4 of force distribution material is unitary and applies to the two opposite faces 2a, 2b of the vertical core of the profile 2 and one of the faces of the horizontal sole of the profile 2. The compression assembly 26 compresses the block 4 of force distribution material in a transverse direction substantially perpendicular to the longitudinal direction 10. It essentially comprises two compression plates 27a, 27b and compression tie rods 28 extending between the compression plates 27a, 27b.

  The compression plates 27a, 27b are substantially parallel to the opposite faces 2a, 2b of the profile 2. The profile 2 and the block 4 of force distribution material extend between the compression plates 27a, 27b. The compression rods 28 pass through the block 4 of force distribution material and are fixed on the compression plates 27a, 27b by nuts 29. The reinforcing profiles 22 extend between the nodes 11 and 12 substantially parallel to the amount 18 in a substantially vertical direction of elongation 30, perpendicular to the longitudinal direction 10 and to the transverse direction 20. These reinforcing profiles 22 have a free end 22a embedded in the block 4 distribution forces. They extend substantially in contact with one another between the nodes 11 and 12, but are bent near their free end 22a to form a non-zero angle with respect to the direction of elongation 30 near their free end 22a, so that they deviate from one another and receive between them the vertical core of the section 2. To set up the reinforcing device illustrated in Figures 4 and 5 from the situation illustrated in FIGS. 2 and 3, the profiled section 2 and the profile 15 are sandblasted near the node 11, or a similar operation designed to allow a high coefficient of friction between the sections 2 and 15 and the material for distributing the profiles. efforts. Then, we put in place the reinforcement profiles 22, the compression plates 27a, 27b and the compression tie rods 28 passing through the gussets 16 and housed in tubular sleeves 21 avoiding their adhesion to the distribution material 2. It is then cast the force distribution material in a substantially liquid state between the two compression plates 27a, 27b. It may be possible to facilitate the introduction of the force distribution material by adding removable formwork elements between the compression plates 27a and 27b. Then, when the force distribution material has at least partially solidified, it comes to apply a compressive force on the block 4 of force distribution material by screwing nuts 29 on the compression tie rods 28, so that the compressive tie rods 28 will be constrained in extension. It will be noted that the compression plates 27a, 27b extend substantially away from the profile 2.

  Advantageously, the force distribution material consists of mortar or a plastic resin. In the embodiment illustrated in FIGS. 6 and 7, the block 4 of force distribution material and the compression assembly 26 are substantially identical to those of the embodiment illustrated in FIGS. 4 and 5. The embodiment illustrated in FIGS. Figures 6 and 7 differs from the embodiment illustrated in Figures 4 and 5 essentially in that the reinforcing profiles 22, passive type, are replaced by reinforcement profiles 32 of the active type, usually known as the butons, extending along the compressed chord 6. The reinforcement section 32 extends in the longitudinal direction 10 of the section 2 between the nodes 11 and 14, parallel to the profile 2, and is in the form of a tube having a free end 32a embedded in the block 4 distribution of efforts. The reinforcement profile 32 exerts on the structure 1 a force 34 tending to move the nodes 11 and 14 in the longitudinal direction 10, so as to take back part of the permanent compression stresses to which the profile 2 could be subjected. This effort 34 is obtained by compressively forcing the reinforcing profile 32 in the longitudinal direction 10 by means of jacks and thus maintaining it by means of shims, according to a technique well known per se. The establishment of the reinforcing device illustrated in FIGS. 6 and 7 is substantially similar to that of the device illustrated in FIGS. 4 and 5, except that the reinforcing profiles 32 replace the reinforcement profiles 22 and that, in an ultimate step, the reinforcing profiles 32 are constrained in compression in the longitudinal direction 10. The embodiment illustrated in Figures 8 and 9 35 differs from that illustrated in Figures 4 and 5 in that reinforcing tie rods 42 are substituted for the profile reinforcement 22 and that the compression assembly is completed by a support plate 47c to form a compression assembly 46. The support plate 47c is connected to the compression plates 27a and 27b and extends in proximity to the upper flange of the stretched chord 6 and in particular the sections 2 and 15. The reinforcing tie rods 42 extend between the nodes 11 and 12 parallel to the upright 18. They pass through the block 4 of material distribution of the stresses housed in tubular sleeves 41 avoiding their adhesion to the distribution material and are constrained in extension by screwing nuts 43 bearing on the support plate 47c by tensioning with a jack. Thus, the reinforcing tie rods 42 exert a force 44 tending to bring the knots 11 and 12 closer together and thus to reduce the stresses to which the post 18 is subjected. The installation of the reinforcement device illustrated in FIGS. 8 and 9 is similar to that reinforcement device illustrated in Figures 4 and 5, except that in an ultimate step, the reinforcing tie rods 42 are constrained in extension by screwing nuts 43 or by tensioning by means of a jack. In the embodiment illustrated in FIGS. 10 to 12, the structure 1 is reinforced by a reinforcing device comprising cables 52, 62, a block 4 of force distribution material, a compression assembly 56, guide tubes 63 forming tubular sleeves and a support 40.

  As in the previously described embodiments, the block 4 of force distribution material is unitary and applies to the two opposite faces 2a, 2b of the vertical core of the profile 2 and one of the faces of the horizontal web of the 2. The compression assembly 26 essentially comprises two compression plates 27a, 27b and compression tie rods 28 extending between the compression plates 27a, 27b. The compression assembly 26 compresses the block 4 of force distribution material in the transverse direction 20. The compression plates 27a, 27b are substantially parallel to the opposite faces 2a, 2b of the profile 2. The profile 2 and the block 4 of stress distribution material extends between the compression plates 27a, 27b. A support plate 57c and a support 40 extend substantially between the compression plates 27a, 27b to which they are connected and close to the upper sole of the sections 2 and 15. The compression tie rods 28 pass through the block 4 of material distribution of forces and are fixed on the compression plates 27a, 27b by nuts 29. The cables 52 are tensioned and fixed at one end to the node 13 and bear against the support 40 by an end head 52a. The ribs 48, extending substantially perpendicular to the longitudinal direction 10, reinforce the support 40 to withstand the forces applied by the cables 52. The guide tubes 63 are clamped in the block 4 of force distribution material and present each a passage 64 receiving the cables 52 and 62.

  The cables 62 are stretched between the nodes 13 and 14 and exert a force on the structure tending to move the nodes 11 and 12, because the passages 64 are not aligned with the nodes 13 and 14. To set up the device reinforcement illustrated in FIGS. 10 to 12 from the situation illustrated in FIGS. 2 and 3, after having sandblasted or the like close to the knot 11, the compression plates 27a, 27b are put in place, the plate of support 57c and the support 40. Then, the guide tubes 63 are placed and their orientation is adjusted. The compression tie rods 28 and their tubular sleeves 21 are then put in place and the material for distributing the forces between the compression plates 27a, 27b is cast. Then, it comes to apply a compressive force on the block 4 of force distribution material by screwing the nuts 29 on the compression tie rods 28. Finally, the cables 52 and 62 are stretched. In the embodiment illustrated in FIGS. and 14, the structure 1 and in particular the section 2 is reinforced by a reinforcing device comprising a corset 72, a block 4 of force distribution material and a compression assembly 76. The corset 72 defines an interior cavity filled with a block 4 of force distribution material and wherein the section 2 is substantially completely received. The corset 72 extends along the section 2 substantially along its entire length in the longitudinal direction 10 between the nodes 11 and 14, between which it is not maintained. It has in cross section perpendicular to the longitudinal direction substantially a U-shape comprising two compression plates 77a, 77b and an intermediate plate 77c connecting the compression plates 77a and 77b. The upper core of the profile 2 extends in the transverse direction substantially between the compression plates 77a, 77b. The vertical core of the section 2, and in particular the vertical faces 2a, 2b of the section 2 extend substantially opposite the compression plates 77a, 77b. Compression tie rods 78 housed in tubular sleeves 71 avoiding their adhesion to the distribution material and forced in extension by nuts 79 applied on the compression plates 77a, 77b tend to bring the compression plates 77a, 77b one towards the other. on the other and thus to compress the block 4 of force distribution material.

  The compression assembly 76 is defined by the compression plates 77a, 77b, the intermediate plate 77c, the compression tie rods 78 and the nuts 79. To set up the reinforcement device illustrated in FIGS. 13 and 14 from FIG. 2 and 3, after advantageously sandblasting the profile 2 between the nodes 11 and 14, the compression assembly 76 is put in place, then the material of distribution of the forces is cast, and finally when this is substantially solidified, it is compressed by screwing the nuts 79. In the embodiment illustrated in Figures 15 to 17, the structure 1 is reinforced by a reinforcing device comprising a profile extension 82, a block 4 of force distribution material and a compression assembly 86. The profile extension 82 extends between the node 14 and an end 82c, in the extension along the longitudinal direction 10 of the profile 2. The profile 2 extends d between the node 11 and the free end 2c in the longitudinal direction 10. The profile 2 and the profile extension 82 are not supported between the node 11 and the node 14. The profile extension 82 thus constitutes an extension of the profile 2, the end 82c of the profile 82 extending in the immediate vicinity of the end 2c of the profile 2. The extension of the profile 82 here has an H-shaped section comprising two substantially horizontal flanges interconnected by a core substantially vertical having two substantially vertical opposite sides 82a, 82b. The profile 2 here has a substantially H-shaped section also comprising two horizontal insolesreliés them by a vertical core having two substantially vertical opposite faces 2a, 2b, but the spacing between the faces 2a and 2b is substantially different from the spacing between the faces 82a and 82b of the profile 82.

  The block 4 of force distribution material extends near the free end 2c of the section 2 on the vertical faces 2a, 2b and near the free end 82c of the profile extension 82 on the vertical faces 82a, 82b and is unitary, so as to connect to each other the profile 2 and the profile extension 82. The compression assembly 26 comprises two compression plates 87a, 87b, 88 88 compression rods extending between the compression plates 87a, 87b and nuts 89 screwing onto the compression tie rods 88. The compression plates 87a, 87b extend parallel to each other and opposite sides 2a, 2b of the profile 2 and the opposing faces 82a, 82b of the profile extension 82. The compression tie rods 88 pass through the block 4 of force distribution material in tubular sleeves 81 avoiding their adhesion to the distribution material and are fixed on the compression plates 87a, 87b pa The compression assembly 86 thus compresses the block 4 of force distribution material in the transverse direction substantially perpendicular to the longitudinal direction against the vertical faces 2a, 2b, 82a, 82b. To set up the reinforcing device illustrated in FIGS. 15 to 17, after having advantageously sanded the profile 2 near its free end 2c and the profile extension 82 near its free end 82c, and then put in place the compression assembly 86, pouring the force distribution material between the compression plates 87a, 87b, then when at least partially solidified, compressing the block 4 of force distribution material by tightening the nuts 89 on the Of course, the invention is not limited to the embodiments which have just been described. In particular, although described separately, the various embodiments could be combined. In all cases, the tightening S exerted by the compression tie rods is dimensioned so as to transmit the longitudinal force F to the opposite faces 2a and 2b, taking into account a useful coefficient of friction f and an adequate safety coefficient y: yF <_ fS where 0, 5 <f <1 and 1.5 <y <2

Claims (3)

  A trellis structure (1) comprising an elongated structural member (2) and a reinforcing device for relieving the elongated structural member of a portion of the stresses to which it is subjected, characterized in that the reinforcing device comprises a force distribution material defining a block (4) applying on two substantially opposite faces (2a, 2b) of the elongated structural member, said block (4) of force distribution material being compressed against said faces of the elongated structural element (2a, 2b).   The structure of claim 1, further comprising an elongate reinforcing structural member (22, 32) having a free end (22a, 32a) embedded in the block (4) of force distribution material.   3. Structure according to claim 2, wherein: the structure comprises a first chord (6) and a second chord (8), the first chord (6) comprises the elongated structural element (2), and -l Elongated reinforcing structural member (22) is attached to the second chord (8) away from said free end (22a) embedded in the block (4) of force distribution material. The structure of claim 2 or claim 3, wherein the elongate reinforcing structural member (32) extends in a longitudinal direction (10) and is compressed (34) in the longitudinal direction (10). 8. Structure according to any one of the preceding claims, wherein: - it further comprises a reinforcing tie rod (42) passing through the block (4) of force distribution material and bearing on a support (27a, 27b, 47c) integral with the block (4) of force distributing material at a first end (11), - the structure comprises a first chord (6) and a second chord (8), - the first chord (6) comprises the elongate structural member (2), and - the reinforcing tie (42) is attached to the second chord (8) at a second end (12) remote from the first end (11). 6. Structure according to any one of the preceding claims, further comprising a cable (52) supported at one end on a support (27a, 27b, 57c, 40) integral with the block (4) of force distribution material, said support (27a, 27b, 57c, 40) incorporating stiffeners (48) in the form of ribs. The structure of any preceding claim, further comprising a cable (62) extending between two anchor points (13, 14) and passing through a passage (64) in the block (4) of material force distribution, said passage (64) not being aligned with the two anchor points (13, 14). 8. Structure according to claim 7, wherein the passage (64) is defined by a guide tube (63) contained in the block (4) of force distribution material. 9. Structure according to any one of the preceding claims, wherein the elongated structural element (2) comprises a portion extending in an elongation direction (10) between two ends (11, 14) between which it is not maintained and the block (4) of force distribution material isencapsulated perpendicular to the elongation direction in a corset (72) and continuously in the elongation direction (10), substantially between the two ends (11, 14 ) of said portion of the elongate structural member (2). The structure of any one of the preceding claims, wherein: the elongate structural member (2) extends to a free end (2c), wherein the structure further comprises an elongate structural member extension (82) having two substantially opposite faces (82a, 82b) and extending to a free end (82c) disposed near the free end (2c) of the elongate structural member (2), where the block (4) stress distributing material extends near the free end (2c) of the elongated structural member on opposite sides (2a, 2b) of the elongated structural member (2) against which it is compressed and near the free end (82c) of the elongated structural member extension (82) on opposite faces (82a, 82b) of the elongated structural member extension (82) against which it is compressed . 11. Structure according to any one of the preceding claims, wherein: the two opposite faces (2a, 2b) of the elongated structural element (2) are substantially parallel to each other, two compression plates (27a, 27b; 77a, 77b; 87a, 87b) which are substantially parallel to each other are connected by tension rods (28, 78, 88) constrained in extension, where the block (4) of force distribution material extends between the plates, and the compression tie rods (28, 78, 88) pass through the block (4) of force distribution material. The structure of claim 11, wherein the compression plates (27a, 27b; 77a, 77b; 87a, 87b) extend away from the elongated structural member (2). 13. Structure according to claim 11 or claim 12, wherein the tie rods (28, 78, 88) are housed in tubular sleeves (21, 71, 81). 14. Structure according to any one of the preceding claims, wherein the force distribution material (4) consists of mortar. The structure of any one of the preceding claims, wherein the force distribution material (4) is made of a plastic resin. 16. A method of reinforcing a lattice structure comprising an elongated structural member (2) and a reinforcing device for relieving the elongated structural member (2) of a portion of the stresses to which it is subjected, wherein the following steps: a) a block (4) of force distribution material is provided on two substantially opposite faces (2a, 2b) of the elongated structural element (2), then b) said block (4) of material for distributing the forces against the opposite faces (2a, 2b) of the elongated structural member (2). 17. The method according to claim 16, characterized in that during step a), the force distribution material is arranged in a substantially fluid state to form the block (4), and the distribution material is then expected to be distributed. efforts are at least partially solidified to compress the block (4) of force distribution material in step b). 18. A method according to claim 16 or claim 17, wherein: prior to step a), two compression plates (27a, 27b, 77a, 77b, 87a, 87b) are arranged substantially parallel to one another two opposite faces (2a, 2b) of the elongated structural element (2), and then the two compression plates are connected by compression tie rods (28, 78, 88), where in step b), constrained the compression tie rods (28, 78, 88) in extension.