WO1999053143A1

WO1999053143A1 - Rigid structure for reinforcing and vertically integrating road structures such as motorways or bridges with joints or cracks

Info

Publication number: WO1999053143A1
Application number: PCT/FR1999/000876
Authority: WO
Inventors: Daniel Doligez
Original assignee: 6D Solutions
Priority date: 1998-04-15
Filing date: 1999-04-14
Publication date: 1999-10-21
Also published as: AU3334699A; FR2777577A1

Abstract

The invention concerns a device and a method for repairing damage caused by slab (2) rocking on motorways or the like, and the damage caused to road structures such as bridges whereof the flooring is not sufficiently strong. The invention is characterised in that it consists in providing perpendicular to the damaged part rigid rods (9), having for example 5.5 x 5.5 mm in cross-section in the direction of traffic, maintained by transverse braces (8). The transverse braces can be replaced with a nonwoven, so that the product can be rolled up. The whole assembly is placed at the interface of the sand asphalt layer (4) and the asphalt (5) or asphalt mix, in one particular but not exclusive embodiment. In the example selected the invention also prevents the formation of cavities.

Description

Rigid structure for vertical reinforcement and joining of rolling structures like highways or bridges with joints or cracks

The present invention relates to the technical sector of reinforcements and reinforcements for road surfaces such as roads, highways, bridges and the like.

The invention applies more particularly to road structures, highways and bridges, comprising in their structure blocks separated by joints, or generally structures having a strong deflection.

Non-limiting examples of such structures are represented in particular by motorways and by certain bridges.

Road structures which include blocks separated by joints are subject to particular phenomena.

On the one hand, there are successive horizontal withdrawal and expansion movements of the hydraulic binder constituting the so-called "rigid" pavements, between the hot periods and the cold periods of the climate. These movements naturally affect in traction the various coatings placed above the blocks forming the base of the track.

On the other hand, the passages of the axles of the vehicles exert a force, vertical that one, on each block. It therefore occurs at each passage of an axle bending of the block subjected to the axle load, then its relaxation when the axle passes over the next block immediately. The first block is therefore subjected to vertical oscillating movements at each charge passage. As for the next block, which is very slightly raised compared to the previous block, since the latter has sunk very slightly under the axle passage, receives the "shock" of the axle on its transverse border , then undergoes the axle load. So each block is therefore subjected, at each load passage, to a shock from top to bottom and then to the axle load then to an upward relaxation towards its initial position, this movement is known to professionals by the term of "slab flapping" . We also mention an alternative phenomenon from top to bottom and vice versa, called "pumping".

Similar phenomena are found during the formation of cracks between the blocks.

The movements which have just been described are of course of small amplitude but their large number causes very significant damage over time.

Not only do these movements alter the quality and integrity of the upper coating layers arranged according to specific needs above the base blocks, but the phenomenon of "pumping" combined with water infiltration and the well-known phenomenon of freezing / thawing can lead to the formation under the joint, or under the crack, of real cavities whose dimensions vary from a few millimeters to a meter. It is specified that, already for a cavity of the order of a millimeter, the beat phenomenon is initiated and damaging for the structure.

If the flapping phenomenon is less than 1 mm, repair operations can be attempted by injecting materials under the tiles, with a very mixed success rate.

If, on the other hand, for example in cases where a motorway has been too long without maintenance, the beat reaches or exceeds 1 or 1.5 mm, public works professionals can no longer deal with the problem. It is then necessary to break the portion of track and completely redo this portion. The direct costs (works) and indirect costs (unavailability of the track) are exorbitant.

Various reinforcements of the strip or ply type, more or less reinforced, are known in the profession, as for example described in French patent application N ° 97 10735 filed on 25 08 97 by

Applicant, but such tapes do not provide a solution to the particular problem posed by the phenomenon of "flapping" at the level of a joint or a crack existing or appearing in a pavement of the "rigid" type, that is to say generally made up of juxtaposed concrete blocks, like a highway especially.

Other prior techniques combine a layer of material with a low modulus of elasticity (relatively flexible cad) with a layer of reinforcement.

European patent EP 0 505 010 is also known, which describes overlays of relatively fine mesh, of metallic wires and flexible metallic cables. It is a reinforcing structure which does not specifically attack the phenomenon of flapping of the slabs. The marketed product comprises a heavy lattice consisting of a lattice of steel wires reinforced by "strands" which are cables with 2 or 3 wires of 3 mm, therefore still very flexible. The brochure also specifies that the mesh obtained has good flexibility in the transverse and longitudinal directions, the strands are therefore not stiffening, and flexibility remains a sought-after quality. Furthermore, this technology does not allow hot work.

In the prior art, a so-called "dowelling" solution has also been developed, employing vertical cylinders. This solution is not entirely reliable and it remains very expensive.

We have also tried in the prior art to deposit successive layers of asphalt at the level of the problem, in order to "cover it", on the one hand, it is a palliative which does not deal with the problem but is limited to masking it for some time, after which it reappears, and on the other hand we are thus led to consider additional thicknesses so large that the initial sizes are no longer respected. This is how, in some cases, the resumption of the roadway forced the bridges crossing it to be raised. The extent of the problem, the cost of its treatment with current palliative measures, and the absence of an effective solution are better measured using such examples. In fact, there is to date a whole range of solutions which depend on the perception of the project manager, with regard to the severity of the beat.

The invention relates to a new structure intended to remedy this problem.

According to the invention, a stiffening element is incorporated in the area to be treated either preventively, during construction, or curatively. When you operate from construction, you avoid the occurrence of the problem. In curative mode, the invention makes it possible to repair a floor without the need either to deposit tens of cm of asphalt on the affected area, or to completely destroy the track.

Attempts have already been made to try to stiffen certain portions of tracks. These attempts were unsuccessful. Mention will be made, for example, of attempts to install metal plates and the like, and in particular galvanized metal reinforcement plates arranged over the entire surface of the track (and not only on the joint or the crack, which is very costly. important), in combination with an under layer of material with low elastic modulus.

Surprisingly, the invention achieves its objective in a simple and reliable manner, and relatively inexpensive.

According to the invention, the area to be treated is stiffened either curatively or preventively by a structure of substantially flat shape, very open and very rigid, capable of integrating into the constituent layers of the track and of working as a reinforcement.

By "substantially planar" is meant a structure which can either be planar or have some undulations, striations or the like, or voluntary to improve the attachment, or involuntary and inherent in manufacturing irregularities.

By "very open" is meant a structure comprising wide openings, regularly spaced or not, of any shape, and distributed over substantially the entire surface of the structure. These openings or meshes must be sufficiently large individually to provide a vertical passage to the materials constituting the pavement, which ensures a good anchoring of the structure in the pavement, without affecting the required rigidity.

By "very rigid" is meant a structure which, although open in the sense above, retains great rigidity, either by its geometry, its thickness etc., or by reinforcing elements. According to the invention, the stiffness modulus of the structure can be specified by the following nonlimiting examples:

bars of 5.5 x 5.5 mm; polyester resin reinforced with glass fibers

Flexural modulus of 40,000 MPa

(according to standard NFT 57105)

Other characteristics and advantages of the invention will appear better on reading the description which follows, and with reference to the appended drawing, in which:

FIG. 1 represents a pavement of rigid type, comprising blocks, generally made of concrete or the like, 1 and 2, placed on the ground. the blocks are covered with a bituminous layer 4 and one or more asphalt layers 5. Between each pair of blocks is a joint 3

Figure 2 shows a rigid type pavement, of the type shown in Figure 1, and illustrates the effect of thermal expansion shrinkage (horizontal arrows f) and "pumping" (arrow F indicating the force exerted by the axle 6 in its position 6A, and arrow C indicating the impact of the axle on the block 2 when the axle passes into position 6B); pumping is constituted as we have seen by these forces and alternately their relaxation after the passage of the axle.

FIG. 3 represents a nonlimiting embodiment of the invention, integrated into a rigid track. FIG. 4 represents the nonlimiting embodiment of the invention, used in FIG. 2.

Figure 5, which consists of Figures 5 a to 5 d, shows non-limiting variants of embodiments of the invention.

- Figure 6 shows another variant of a non-limiting embodiment of the invention.

FIG. 7 represents a metallic type bridge structure and the integration of an element according to the invention.

FIG. 8 represents nonlimiting positioning modes of the invention, playing on the laying angle with respect to the joint or to the crack.

FIG. 9 represents nonlimiting variants of embodiments of the invention.

FIG. 10 represents nonlimiting variants of embodiments of the invention.

Figure 1 1 shows non-limiting variants of embodiments of the invention.

In the different figures, the same references designate the same elements.

Figures 3 and 4 show the general principle of the invention. This involves placing a rigid structure as defined above in the direction of flow (indicated by the arrow SC).

According to the preferred variant shown, the structure 10 according to the invention is composed of rigid bars 9 relatively long. Their cross section can be square as shown, or different, for example round, oval, or triangle or other. Length is a function parameters such as the severity of the problem to be treated, the nature of the pathway, the nature of its damage, whether it is a curative or on the contrary preventive treatment, and other parameters on which the profession will be able to act by a few simple tests in the field.

According to the variant shown, the bars are rectilinear, but one can also envisage slightly sinusoidal bars along their length, so as to distribute the load even better, or other forms capable of effecting a better distribution; the only limit in this area is not to weaken the rigidity and not to increase the cost of manufacturing and implementation too much.

To improve the mechanical anchoring, bars or notched or rough rods may be used, according to a non-limiting variant of implementation.

According to the variant shown, the bars are held together by spacers 8. These spacers are shown, according to the non-limiting variant used, with a rectangular cross section. Other sections are of course possible, on condition of not weakening the solidity of the assembly, of facilitating the attachment of the spacers in the layers 4, 5 of the track, and of not increasing the manufacturing cost too much and of implementation.

In this example, the spacers and bars are glued to their junction points with an adhesive capable of withstanding the high temperatures of casting of layers 4 and 5.

In general, layer 4 will be a layer of 1 to 3 cm

(although there is no upper limit, except the cost) of a "coated sand" which consists of fairly fine sand to which about 10% by weight of bitumen is added. The assembly is known to those skilled in the art under the term "SAMI". Its modulus of elasticity is around 9000 MPa at 15 ° C and 10 Hz. Layer 5 generally consists of a layer of asphalt "or" bituminous concrete "(" asphalt "or" asphalt mix "), of thickness compatible with its function as a tread or possibly of pavement structure.

Optionally, other layers may be present, and a sandwich-type structure deposition may be carried out by integrating the product according to the invention in several thicknesses, with the traditional materials based on bituminous binder or the like between the two products. . Several thicknesses of constituent materials of the roadway can be put in place, according to the rules of the art.

As seen in Figure 3, the structure according to the invention is arranged on the layer 4 at a time when it is still sufficiently fluid so that the spacers 8 can be anchored therein. On the other hand, the bars 9 remain substantially on the surface of the layer 4.

Those skilled in the art will however understand that the effect of the invention is also achieved if the bars 9 are also anchored by themselves in the layer 4, at least in part.

According to a variant which can be very advantageous in many cases, the bars 9 are glued (or otherwise fixed, for example by partial melting or the like) on a nonwoven strip which replaces the spacers 8. Such a nonwoven strip 40 is shown in Figure 5 d. One advantage is that the structure can be rolled up, and another advantage is that the strip of nonwoven fabric will eventually be destroyed by fusion when the layer 5 is cast or by "punching" with the aggregate. This can be interesting in certain configurations.

According to another variant, simpler to implement, the bars can be simply connected by braids transverse to the bars; the assembly is then remarkably easy to manufacture, transport and set up. According to yet another variant, the bars can take the form of "rods" of circular cross section, or any other form accessible to those skilled in the art.

During the passage of a load on the portion of track treated by the invention, there may be oscillations of the structure of the invention itself, the end being able to rise in particular when the load is substantially in the center. This clearly shows the technical difficulties encountered during the development of the invention, and explains why no practical solution exists to date.

To reduce or eliminate this drawback, it is of course possible to increase the thickness of the layer 5, but this presents an additional cost and, moreover, there may be problems of size. One can also think of lengthening the bars 9, but there is also an additional cost.

According to the invention, it is proposed to terminate the rigid structure according to the invention by two zones (one in front and the other behind with respect to the direction of circulation) by two zones of progressive rigidity.

Several variants have been shown in FIG. 5, as well as in FIG. 6.

In Figure 5, Figure 5a shows the normal structure. FIG. 5b represents a structure with zones Z1 and Z2 of progressive rigidity owing to the fact that the bars 9 ′ are offset with respect to the bars 9. likewise in FIG. 5 c, the bars 9 ′ are longer than the bars 9. Finally , in FIG. 5 d, two bands b1 and b2 are provided which consist of a conventional reinforcement or reinforcement of the ROTAFLEX (TM) type or the like, which extends the rigidity of the structure by two reinforced but non-rigid zones.

Other configurations will be apparent to those skilled in the art. 10

In particular, the spacers 8 can be replaced in whole or in part by a nonwoven strip 40 capable of having a sufficient open character according to the above criteria of the invention.

FIG. 6 represents a variant where the region of progressive rigidity is obtained by variation of the cross section of the bars 9.

FIG. 7 represents another case of serious damage to the road which we do not know how to deal with to date and which the invention, surprisingly, also makes it possible to resolve. Some bridges have a frame or deck 30, generally made of steel, resting on supports 31. It quite frequently happens that, for various reasons, the frame 30 has been undersized. In certain well-known cases in Northern Europe in particular, we observe this scenario. The supports 31 are, in this case, distributed approximately every 30 cm. The frame 30 is coated, in this type of bridge, first with a thin layer of bitumen 32 for waterproofing (often a bituminous membrane known to those skilled in the art, of usual thickness 1 to 5 mm or even upper) then two layers 33, 34 of each 10 to 40 mm approximately of asphalt poured typically at 210 ° C or even 240 ° C. On passing a load, like that of an axle 6, there is a deflection of the structure, shown in FIG. 7 by the dotted lines marked FL. Over time, these successive deflections and relaxations cause cracks to form in the deck deck itself and / or the upper bituminous layers or wearing courses. To reduce or prevent sagging, it has of course been thought of placing plates, in particular of steel, over the entire surface of the bridge. However, there is no known technique capable of hanging such plates on the bitumen., And the plates quickly peel off and separate. The only solution is then often to build a new bridge next to the old one, which is destroyed, we clearly measure the acuity of the problem.

According to the invention, a structure 10 (which can take any of the various variants which have just been described) is positioned on the layer of bitumen, where it is capable of anchoring, then the layer or layers is poured of asphalt. Positioning is symbolized by the arrow. 1 1 we see that we place the bars 9 substantially perpendicular to the direction of flow SC, and the spacers 8 substantially parallel. As shown in Figure 8, you can also choose an oblique positioning for better load distribution. Either bars 9 can be used connected by spacers 8 glued with an adhesive which is preferably resistant to a temperature of at least 210 ° C, or resistant at least to approx. 150 ° C (the difference in heat resistance being due to the consideration of the thermal inertia of the materials in question), like known epoxy adhesives (for example two-component structural epoxy adhesive with Shore hardness of about 80 ) of the skilled person, either connect the bars 9 with a nonwoven which will be destroyed or melted during casting.

So that the stiffening material according to the invention brings the maximum effect to the general structure, it is advantageous to apply it as "low" as possible. It will then, for example in FIG. 7, be placed between layers 32 and 33. As indicated above, it may be arranged in a “sandwich” structure, ie an element between layers 32 and 33 and an element between layers 33 and 34. When the material is applied directly to the layer 32, the layer 33 will generally be applied manually since, in this case, the material is in the transverse direction relative to the direction of circulation on the roadway, and that the material according to the invention cannot and must not sink into layer 33.

To solve the problems posed on a structure of the bridge type, one will preferably not use metal bars, because of the respective coefficients of expansion, one will choose a composite material, or another material whose coefficient of expansion will be adapted to the conditions temperature of the placement of bituminous materials, and / or will be adapted to the climate.

In Figure 8, there is shown a combination of the structure according to the invention with the geometry of the joints 3 (or cracks). It can often be advantageous to install the structure according to the invention, and in particular the bars 9, or 9, 9 ′ according to the variants, according to a certain angular inclination relative to the passage E of an axle. We 12

distributes the load better. In the example of FIG. 8, the spacers 8 have been replaced by a nonwoven 40 in strip form.

Preferably, the bars 9 will be made of materials such as a composite of glass fibers and polyester resin, or alternatively of galvanized steel, the coefficient of expansion of which will be adapted to the temperature conditions of use of the bituminous materials and / or the climate in which the road is located, the problems often being dependent on latitudes.

The spacers 8 will for simplicity be made of the same material.

For very high temperature applications, materials such as charged polyesters and the like will be preferred.

EXAMPLES

Example 1: Structure to Fight Against the Flapping of Slabs

Bars and non-woven

The stiffening elements consist of bars with a square section of 5.5 x 5.5 mm, made of polyester resin (possibly reinforced with glass fibers). The bending module of the bars is 42,000 MPa according to standard NFT 57105.

The bars are 2 m long and have a rough surface. The bars are coated with bitumen.

The bars are spaced 50 mm apart, and are arranged by hot laminating on a polyester nonwoven at 20 g / m2, to form a structure according to the invention, which can be rolled easily, for example in length of 9 m (which corresponds to the width of two tracks). 13 Example 2: Structure to fight against the flapping of slabs.

Bars and spacers

2.1 The elements are the same bars as in Example 1, of section 5.5 x 5.5 mm, made of polyester (possibly reinforced with glass fibers), with a rough surface, but in length of 1 m.

They are spaced every 100 mm (10 cm).

They are placed and glued on a polyester resin spacer of square section 5.5 x 5.5 mm, the spacers being spaced every 200 mm (20 cm). We used an epoxy glue.

A structure according to the invention of 1.40 m in width, shown in FIG. 9, is produced. It can be seen that the bars have been offset so as to form "V" ends as shown.

2.2 The same elements are used as above, but by making the structure as shown in FIG. 10 where a single spacer 8 has been shown.

Example 3: Reinforcement in the event of subsidence.

3.1 Elements 9 are polyester rods with a rough surface, with a cross-sectional diameter of 10 mm. Their modulus of elasticity is from 50,000 to 70,000 MPa.

We use 13-meter rods coated with bitumen, hot laminated on a polyester nonwoven at 20 g / m2.

The rods are spaced 200 mm (20 cm) apart.

We obtain a well integrated structure in asphalt. The structure can be constructed as shown according to the various variants indicated in the attached figures. 14

3.2 The same structural elements as in 3.1 were used, but not coated with bitumen and the structure being integrated into the earthmoving materials.

We used a nonwoven 60 of width less (eg 10m) to the size of the rods, as shown in Figure 11 attached, to allow good anchoring of the ends EX of the rods 9 in a concrete support, for example.

The nonwoven used may be a geotextile, which will provide in a single operation the reinforcement functions and those specific to the geotextile.

3.3 Metal rods of steel with a diameter of 10 mm were used, with a modulus of elasticity of 150 to 200,000 MPa.

Polyethylene glue was laminated to a polypropylene nonwoven at 30 g / m2.

A 3 m wide structure was developed, with 13 m rods and a 10 m wide nonwoven, according to the model in Figure 11.

Such a structure is integrated into the soil at neutral pH, slightly corrosive, with a spacing of the rods chosen at 200 mm.

This material can be rolled.

The width of 3m (in all the examples and embodiments presented here) depends on the weight of the roll which must remain easy to handle, ie approx. 80 kg max.

Example 4: Reinforcement of bridge deck.

Bars of square section 5.5 mm x 5.5 mm are used in charged polyester. The flexural modulus is of the order of 40,000 MPa.

We select a rough and notched surface. 15

The resistance to a temperature> 180 ° C is of the order of 10 min.

The bars are coated with bitumen, and hot laminated on a polypropylene nonwoven at 17 m2 / g.

The bars have a length of 5 to 8 m and are spaced 50 mm apart. We prepare a rolled structure of approximately 10 m which we will place as indicated above.

According to another variant of the invention, and depending on the problem to be treated, or its severity, the structure according to the invention can also be deposited in two thicknesses as shown in FIG. 12 appended, in order to establish a sandwich structure using a matrix of bituminous materials or the like. Depending on the problem, the bars can be placed as shown in any of Figures 5 and 8, 9, 10 or 11.

In Figure 12, we understand that the area (a) of the bars may come off the support due to thermal shrinkage, but will help to help the area (c) to support vertical movements. We will make sure that the zone (a) is much longer than the zone (a) so that (b) remains correctly glued during the movements of withdrawal of the support. Likewise, the length (a) may be identical to (b), but during the implementation in situ, (a) will not be bonded to the support and / or to the bituminous layer 4.

The structures according to the invention are laid by deposition on the lower layer, after a few operations of compacting this layer but before its last compacting operation. The structure according to the invention is then laid and the final compaction of the lower layer is then used to anchor the structure in said layer, the upper layers are then poured.

According to a variant of the invention, an additional lower layer can be deposited to further facilitate attachment, such as a layer of bitumen emulsion which may have special fluidity characteristics. On the bridge type structures mentioned above 16 above, we can deposit a layer of glue resistant to high temperatures.

According to yet another variant of the invention, the structure of the invention may be coated or coated, before the laying operation, in whole or in part, with a layer of product facilitating the attachment, such as a layer of bitumen , a high temperature adhesive or the like.

According to another variant of the invention, it may be decided to dig slightly (2 to 10 cm or 20 cm depending on the thickness of the slab) the concrete blocks 1, 2 around the joint (or around the crack ) across the width of the track. The structure of the invention will be placed in the cavity thus formed, reconstituting if necessary the lower attachment layer, and the procedure is carried out as above, the advantage is to drown the structure according to the invention more deeply, which allows have a greater thickness of wearing courses above the structure, without having to modify the template.

According to another variant, as shown in the attached drawing, the structure according to the invention is laid with the bars in the direction of circulation or transversely, and is laid either perpendicular to the damage or at an angle to the line of damage.

Claims

17 CLAIMS

1. - Reinforcement structure of road structures having joints or cracks, characterized in that it is very rigid.

2. - Reinforcement structure of road structures having joints or cracks, according to claim 1, characterized in that it is formed by a structure of substantially planar shape, very open and very rigid, capable of integrating into the layers constituting the track and working as a frame.

3. - Structure according to claim 1 or 2, characterized in that it (structure 10) comprises rigid bars 9 relatively long.

4. - Structure according to claim 3, characterized in that the cross section of the bars 9 can be square or round, oval, or in a triangle.

5. - Structure according to claim 3 or 4, characterized in that the bars are rectilinear

6. - Structure according to any one of claims 3 to 5, characterized in that the bars are bars, or rods, notched, or rough.

7. - Structure according to any one of claims 3 to 6, characterized in that the bars are held together by spacers 8.

8. - Structure according to claim 7, characterized in that the spacers have a rectangular cross section.

9. - Structure according to claim 7 or 8, characterized in that the spacers and the bars are glued to their junction points by a 18 adhesive capable of withstanding the high temperatures of casting of the wearing courses of the roadway.

10. - Structure according to any one of claims 3 to 6, characterized in that the bars 9 are glued (or otherwise fixed, for example by partial fusion or the like) on a strip of nonwoven, and are made of polyester, polyester reinforced with glass fibers, composite, or metal.

11. - Structure according to any one of claims 3 to 6, characterized in that the bars are simply connected by transverse braids relative to the bars.

12. - Structure according to any one of claims 3 to 11, characterized in that it comprises a structure with zones Z1 and Z2 with progressive rigidity in that the bars 9 'are offset with respect to the bars 9.

13. - Structure according to any one of claims 7 to 12, characterized in that the spacers 8 can be replaced in whole or in part by a nonwoven strip 40 capable of having a sufficient open character

14. - Structure according to any one of claims 1 to 13, for the reinforcement of a bridge type structure.

15. - Structure according to any one of claims 1 to 14, characterized in that the stiffening elements consist of bars with a square section of 5.5 x 5.5 mm, made of polyester resin (possibly reinforced with fibers of glass) and the bending module of the bars is 42,000 MPa according to standard NFT 57105.

16. - Structure according to claim 15, characterized in that the bars are 2 m long and have a rough surface. 19

17. - Structure according to claim 15 or 16, characterized in that the bitumen bars are coated.

18. - Structure according to any one of claims 15 to 17, characterized in that the bars are spaced 50 mm apart, and are arranged by hot laminating on a polyester nonwoven at 20 g / m2, to form a structure that can be rolled in length of 9 m.

19. - Structure according to any one of claims 1 to 14, characterized in that the elements are bars of section 5.5 x 5.5 mm, in polyester reinforced with glass fibers, with rough surface, length of 1 m.

20. - Structure according to claim 19, characterized in that the bars are spaced every 100 mm (10 cm).

21. - Structure according to claims 19 or 20, characterized in that the bars are arranged and glued with epoxy adhesive on a spacer made of polyester resin of square section 5.5 x 5.5 mm, the spacers being spaced every 200 mm (20 cm).

22. - Structure according to any one of claims 3 to 21, characterized in that the bars 9, 9 ', 9 "have been offset so as to form" V "ends.

23. - Structure according to any one of claims 1 to 14, characterized in that the elements 9 are polyester rods with rough surface, with a cross-sectional diameter of 10 mm, of modulus of elasticity from 50,000 to 70,000 MPa .

24. - Structure according to claim 23, characterized in that rods of 13 meters coated with bitumen, hot laminated on a polyester nonwoven at 20 g / m2 are used and the rods are spaced 200 mm (20 cm). 20

25. - Structure according to claim 24, characterized in that a nonwoven 60 of width less (eg 10m) has been used than the size of the rods.

26. - Structure according to claim 24 or 25, characterized in that metal rods of steel with a diameter of 10 mm have been used, with a

Modulus of elasticity from 150 to 200,000 MPa.

27. - Structure according to any one of claims 1 to 14, for the reinforcement of a bridge type structure, characterized in that bars of square section 5.5 mm x 5.5 mm are used in charged polyester , of Flexural modulus of the order of 40,000 Mpa, with a rough and notched surface.

28. - Structure according to claim 27, for the reinforcement of a bridge type structure, characterized in that the bars are coated with bitumen, and laminated with heat on a polypropylene nonwoven at 17 m2 / g.

29. - Structure according to claim 3 or 4, characterized in that the bars are slightly sinusoidal along their length.

30. - Structure according to claim 3 or 4, characterized in that the bars have along their length a suitable shape in order to operate a better distribution of the load.

31. - Structure according to any one of claims 3 to 1 1, characterized in that it comprises a structure with zones Z1 and Z2 with progressive rigidity because the bars 9 'are longer than the bars 9.

32. - Structure according to any one of claims 3 to 11, characterized in that it comprises a structure with zones Z1 and Z2 of progressive rigidity due to the fact that two bands b1 and b2 have been provided which consist of a classic ROTAFLEX (TM) reinforcement or reinforcement 21 or the like, which extends the rigidity of the structure by two reinforced but non-rigid zones.

33 - A method of reinforcing road structures characterized in that the area to be treated is stiffened either curatively or preventively by a structure according to any one of claims 1 to 32, of substantially planar shape, very open and very rigid, capable to integrate into the constituent layers of the track and to work as a reinforcement, at the level of damage 3.

34. - A method for reinforcing a road structure, according to claim 33, characterized in that the structure according to the invention can also be deposited in two thicknesses in order to establish a sandwich structure.

35. - Method for the reinforcement of a road structure, according to claim 33 or 34, characterized in that the structure according to the invention is laid with the bars in the direction of circulation or transversely, and is laid either perpendicular to the damage or at an angle to the damage line.