EP0939164B1 - Construction method for a railway track - Google Patents

Abstract

The construction process for a tramway track (16) comprises several stages. The sides (3,4) and the underside (5) of a rail (1) are coated with a resilient material (2) before placing on supports (10) on top of a foundation baseplate (13). The supports are adjusted into a position where the surface of the rails is at the same level as the track surface. Concrete (31) is then poured around and under the coated rail to form the road surface (32).

Description

The present invention relates to a method of construction a railway line, preferably a railway line in site particularly for the construction of a tramway. She may be nevertheless useful in other fields, rural railways, where the problems encountered are of the same type as those solved by the invention.

A railway line in an urban site generally consists of four subsets: a platform that lies under a foundation layer, a tread of the tram that supports the rail and its anchors and a coating layer which constitutes the apparent part of the structure completed. The latter can be made of various materials: earth grassed, one or more layers of bituminous concrete and asphalt asphalt, pavers, concrete slabs, sand-laid stones, gravel, or concrete. US-A-5 285 964 shows such a method of construction of a railway line in an urban site. The realization of a railroad track in an urban site for tramway involves a number of constraints that must be met imperatively. As regards the tramway, with electric traction, the current return must be provided by the rails. As a result, continuity electrical must be ensured without defects. Indeed, many networks Public facilities are buried in city roads. But leaks of current through the rails cause electrolysis phenomena of metal parts of the various buried networks. The problem is particularly serious with regard to the transport of gas, where the alteration pipes can lead to gas leaks which themselves give explosions when the gas, which escapes, accumulates in a pit, a cellar for example. To avoid this problem, it is necessary to isolate the rail as much as possible, electrically, from the environment in which it rests.

In addition, especially when the rail is made in a road urban, it must not be the seat of water infiltration. Indeed, the water infiltrating into the surrounding pavement body causes phenomena of plastic lifts that undermine the behavior of the foundation. The roadway is degraded because it is no longer waterproof.

Finally, we are paying more and more attention, today, to the effects of noise caused by the shocks and vibrations of the wheels of trains and vehicles that cross the rails and spread to homes nearby.

It is already known, to remedy this type of problem, to ask rails on pedestals, usually sleepers, and then provide rails of an elastic coating protection. EP-A-0 308 876 gives an example of coating elastic of a rail. The difficulty encountered comes from what the rail, in place, is maintained about every 70 cm, or even every 50 cm on the sleepers, and that the incorporation of the coating protectors is tedious on the one hand, and not very effective on the other.

Indeed, where the rail rests on sleepers, it is not possible to ensure the continuity of the coating. This results in troubles partial, but not negligible. In addition, in the case of track realization urban railway, it is necessary that the top of the rail is flush with the level of the floor. Because of the mode of operation thus imagined, poses of rails, fixings rails, cover sections of rails, and space upgrades around the rails, the four-step labor load becomes heavy to support.

This problem is particularly felt in countries developed, who are otherwise lovers of tramway, where the workforce is never cheap. In addition, in an attempt to solve the problem of discontinuity of the coating sections, accessories have been produced, finally very complex to put in place. In particular, the fixing of the rail and / or the fixing of the coating sections, requires the establishment of Temporary supports that must be removed before finishing the coating. These accessories also hinder the automatic installation of the coating by a slip-form type machine in the case of realization of a cement concrete.

The present invention aims to remedy these disadvantages by a completely different process, calling into question all the techniques used so far. According to the invention, we give up fixing rigidly, from place to place, conventionally, the rail on sleepers or supports. On the contrary, we coat the rail, before its installation on its entire length, on the sides and underneath, so that it is completely embedded in an elastic material.

Of course, the coating does not cover the rail, the part of which will still be used as a running surface for the train. Because of the I-shape of the rail, the coating then constitutes a self-locking structure maintaining the rail throughout its length. This maintenance, while being elastic, is performed continuously. It does not need to be as powerful as intermittent fixation. As a result, the rail is well kept in its coating.

Moreover, the coating is itself then kept in place in concrete poured over its entire length so as to ensure its maintenance in the body of the roadway in the case of concrete pavement of cement.

It will be shown that the method of the invention makes it possible to perform three steps instead of four previously, the establishment of the rail.

The subject of the invention is therefore a method of constructing a urban railroad track as defined in claim 1.

• Figure 1 : une représentation schématique de la mise en place d'un rail selon le procédé de l'invention,
• Figures 2a et 2b: les détails d'une phase d'enrobage du rail selon une étape essentielle du procédé de l'invention,
• Figure 3 : une variante de réalisation de l'enrobage permettant une amovibilité du rail dans son enrobage.

The invention will be better understood on reading the description which follows and on examining the figures which accompany it. These are given only as an indication and in no way limit the invention. The figures show:

• Figure 1: a schematic representation of the implementation of a rail according to the method of the invention,
• 2a and 2b: details of a coating phase of the rail according to an essential step of the method of the invention,
• Figure 3: an alternative embodiment of the coating for a removability of the rail in its coating.

Figure 1 shows, schematically, the different stages of the method of the invention. It shows a rail 1 embedded in a coating 2. The coating 2 may be rubber, PVC or any other material elastic, in particular a polymer. The coating 2 will naturally have a certain rigidity. The coating 2 coats the rail 1 essentially on the sides 3 and 4 of the rail, and under the underside 5 of the rail. For example, layer 5 under the rail will be about 2 cm thick. The coating forms at top of the rail a surface that extends the rail on both sides to the same level or at a nearby level, the rail may be slightly protruding. So coated, the rail 1 forms a box whose section is of the order of 20 cm by 20 cm. In the example shown, the rail 1 is an oared rail 6. Nevertheless, it is conceivable to provide simple rails. In that case, the coating 2 will have a cavity to allow the insertion of the flange of the wheel of the train.

The coated rail is preferably carried, at least locally, in cradles 7. Cradles 7 are metal parts, shaped overall of U and which follow the shape of the section of the rail embedded in its lower part. Cradles 7 are not necessary if the material wrapping elastic is sufficiently rigid. They can be particularly useful if this material is rubber.

The cradles 7 are provided, on their vertical flanks, with on the other side of the coated rail, crows 8 each having a threaded bore 9 vertical. In the bores 9, are threaded rods 10 whose head can be maneuvered in a rotation 11 to sink more or less the 9. The threaded rods 10 have a base 12 which rests on a foundation plate 13 made beforehand.

For example, the sole 13 is made on the bottom 14 of a trench 15. Trench 15 is made in an existing roadway 16. The pavement 16 can also be a pavement to create. The base 12 of the rod 10, rests on the foundation plate 13, preferably via of a reaction plate 17 which avoids its penetration into the foundation 13. In Indeed, it can be equipped with various networks: remote indication 18, power supply 19, or others. The reaction plate 17 is particularly necessary if the constitution of the footing is made with lean concrete with little resistance. Otherwise, we can do without it.

By acting on the threaded rods 10, the rail can be adjusted vertical position, so that its upper surface is flush at the height of the finished roadway 16. Preferably, the lengths of the stems 10 will be less than the height between the plate 17, or the footing 13, this altitude of pavement finished. In this way, at the end, it does not will not be necessary to remove the threaded rods 10 that will remain lost in the coating concrete mass.

To make a path, of course, two rails are put in place and a second rail 20 can be put in place in the same way as the rail 1. The rail 20 will also be adjusted in spacing relative to the rail 1 by a spacer 21 having a double flange 22, worm.

The spacer 21 thus comprises two threaded rods 23 and 24 which take support, in thrust and traction, in two crows 25 and 26 respectively. By a rotation 27 of the flange 22, the spacing of the rails 1 and 20. If the coating material is relatively soft, crows 25 and 26 will be carried by cradles 7 and 28. By However, if the material 2 is more resistant, the crows can be applied directly. The altitude position of the spacer 21 will be significantly lower than the finished road surface. 16. Where necessary, crows 25 and 26 will be fixed under the cradles.

Once the rails coated with elastic materials are thus supported and adjusted above the foundation plate 13, one sinks in place a mass of concrete to hold the rail. Concrete can be a concrete cement, bituminous concrete or, more generally, any material allowing a setting by casting and then making a catch hardening hydraulic, thermal (asphalt) or even chemical (emulsion). This casting in place is obtained by a device 29 of dispensation located at the front with respect to a direction of advance 30 of a set 34 of set up. Exemption 29 may include several spreading openings located in particular on both sides and between the two rails 1 and 20. Fluid concrete 31 flows thus above the sole 13, under the lower part 5 of the coating 2, and on both sides of the flanks vertical rails embedded. At the back of dispensation 29 is a rule smoothing 32 and a vibrating needle 33 which is immersed in the mass, relatively liquid, concrete that has just been put in place.

Exemption 29, Rule 32, Needle 33 and others equipment are carried by a carriage 34 which has the particularity of rolling directly on rails 1 and 20 or on the roadway 16 while being guided by rails 1 and 20. If the railway is not to be made in a trench 15, but in elevation only above of an existing sole 13, the carriage 34 will also carry formwork side. In this case, the type of concrete used will be such that after sliding formwork, its hold is sufficient not to collapse.

It follows from this way of doing that the operation of level of the pavement on the edges of the coated rail, can be carried out a pass. In particular, the position of the spacer 21 will be sufficient deep so that the vibrating needle 33 can pass over for hang. Similarly, in the case where the coating layer has to be performed differently from the wearing course, the mass 31 is set to a level lower than the final surface to allow the setting up subsequent coating layer.

For various reasons, it may be necessary to remove stems 10, and possibly the spacers 21. However, it is found that the rail carries by its sole 5 directly on the underlying mass of concrete. Therefore, there is no risk of creating a hard point to where the crows 8 are attached to the cradles 7. In these circumstances, the removal of rods 10 and spacers 21 is not essential. The supports 10 and 21 are actually provisional, even if they are not removed because in the end they contribute very little to maintaining the rails. This maintenance is ensured by the surrounding concrete.

Figures 2a and 2b show a preferred prior phase of realization of the coating of the rail 1. The coating 2 is in the form a profile having, substantially, the definitive form that it must have around the rail. In a first phase, the flanks 3 and 4 are spread apart from the coating 2. However, it is possible to deliver on the site a coating profile already rest.

Under these conditions, the wings 35 and 36 of the base of the rail 1 are introduced into cavities 37 and 38 respectively of the coating 2. This being achieved, the coating 2 is closed by pressing on the flanks 3 or 4. need, we use strapping 380 PVC or iron, the type of those used in the field of packaging. These strings will be lost by the after. We will cut the upper part.

Figure 2b shows a workshop for producing the coating of the rail. A section 39 already coated rests on trestles 40. A section to embedding 41 has a continuity with the rail section 40, including by welding sections of rail. A section 42 of coating is put in according to the description of Figure 2a. Once this implementation carried out, or during this installation, section 42 is pushed back to the section 40 so as to minimize leakage. If necessary, apparent section 43 between the sections 40 and 42, may be provided with an adhesive to ensure the continuity of the coating. At the other end, the rail 1 is worn by trestles 44. Then we move the workshop for a next section.

FIG. 3 shows an example of a particular form of the coating 2 in which it is made in the form of several sections nestable. The coating 2 may thus comprise a first part 45 forming the flank of one side and the soleplate. It also includes two other parts 46 and 47. Part 46 has a profile that must conform to the shape 1. It has a globally flat shape to fill just the space below the mushroom 48 of the rail 1. The third part 47 completes the overall shape of the coating so that it is the same type as seen previously. Parts 46 and 47 thus form keys whose subsequent removal allows to remove the rail 1 to replace it.

The removal is carried out as follows: Part 47 is taken vertically in one direction 49. Then part 46 is moved laterally in a direction 50 before being also elevated in direction 49. Once parts 46 and 47 are removed, rail 1 may be himself removed by an elevation and possibly a slight rotation.

Figure 2a also shows possible breakthroughs be made from place to place in the rail 1. In correspondence, the coating 2 will have growths. Furthermore, the coating 2 may comprise patterns in relief in relation to his profile. For example, the coating 2 can have a shape with wings 51 and 52 to be held properly on and at the bottom in the mass of concrete. The wings 51 and 52 can be realized on key coating elements or on embedding elements normal.

When the coating 2 is made in several parts, it is possible to take advantage of this feature and to have a key profile to force the tightening of the lips of the coating on the holding shape 31 after drying of this form. With such removable profiles, it is possible to thus to reinforce the maintenance of the rails after the catch. For example part 47 allows horizontal expansion at the point of the arrow 50.

Claims (11)

1. A method of building urban rail track (16), in particular for a tramway, in which:

   the sides (3, 4) and the bottom (5) of a rail (1) are clad with resilient material (2) to form a cladding profile flush with the top surface of the rail;

   a foundation slab (13) is laid in an urban street;

   after the rail has been clad, it is supported (10) and adjusted (21) above (17) the foundation slab by means of temporary supports in a position such that the final position of its top surface is substantially flush with the surface of the urban street;

   a mass (31) of concrete is cast (29) around and below the clad rail up towards the surface of the urban street both to hold the rail and to serve in forming the road surface; and

   the mass of concrete is cast by means of sliding shuttering-by causing the sliding shuttering to slide relative to the rail (1, 20), said sliding shuttering being borne by a carriage (34) moving directly on the rails.
2. A method according to claim 1, characterized in that:

   two rails (1, 20) are supported by means of temporary supports; and

   the two rails are coupled together by means of temporary links.
3. A method according to claims 1 or 2 characterized in that:

   temporary rail supports and/or temporary inter-rail links are implemented with spacers of size that is adjustable (11, 27) by screw means.
4. A method according to any one of claims 1 to 3, characterized in that:

   a resilient shaped section member is made provided with a cavity (36, 37) for receiving the rail;

   the shaped section member is opened, and the rail is inserted therein; and

   the shaped section member is re-closed (38) around the rail.
5. A method according to claim 4, characterized in that:

   the shaped section member is re-closed around the rail by means of lost hoops.
6. A method according to any one of claims 1 to 5, characterized in that:

   at least at the temporary supports or links, cradles (7) are placed for supporting the clad rail.
7. A method according to any one of claims 1 to 6, characterized in that:

   reaction plates (17) are placed on the foundation slab to serve as abutments for the temporary supports.
8. A method according to any one of claims 1 to 7, characterized in that:

   the rail is provided with anchors projecting in relief from its profile so as to remain incorporated in the cladding.
9. A method according to any one of claims 1 to 8, characterized in that:

   the cladding of the rail is provided with anchors (51, 52) projecting in relief from its profile so as to remain incorporated in the mass of concrete.
10. A method according to any one of claims 1 to 9, characterized in that:

    the rail is clad with a shaped section member in a plurality of portions, at least one of which is removable.
11. A method according to claim 10, characterized in that:

    the removable portion is removed and the lips of the cladding are forced to clamp against the holding bed after the operation in which the rails are bedded into the mass of concrete.

Images