Classifications

• • E—FIXED CONSTRUCTIONS
  • E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
  • E01B—PERMANENT WAY; PERMANENT-WAY TOOLS; MACHINES FOR MAKING RAILWAYS OF ALL KINDS
  • E01B5/00—Rails; Guard rails; Distance-keeping means for them
  • E01B5/02—Rails
  • E01B5/04—Grooved rails
• • E—FIXED CONSTRUCTIONS
  • E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
  • E01B—PERMANENT WAY; PERMANENT-WAY TOOLS; MACHINES FOR MAKING RAILWAYS OF ALL KINDS
  • E01B21/00—Track superstructure adapted for tramways in paved streets

Definitions

• the present invention is in the railway field, more particularly in the field of urban rail transport means, including tramway tracks.
• a tramway in the city is subject to many constraints because the basement is in many places and at various depths occupied by networks.
• a tramway in the city must be compatible with car traffic in particular, which involves burying the slabs to support the track to be built so that the top of the rails is at ground level. This excavation usually leads, prior to the construction of the road itself, to divert the existing networks. This is a long, extremely costly and time-consuming task.
• a concrete track slab for example of extruded concrete, of sufficient strength, intended to support the track or the two parallel tracks.
• the engravures are intended to receive the rails, they have a width slightly greater than the width of the runner of the rails, and a depth slightly greater than the height of the rail.
• the top of the rails to be located substantially at the upper face of the track slab, it follows that the depth of these engravures and the thickness of this slab are mainly conditioned by the height of the rails. There is therefore a strong interest in using the lowest rails possible.
• Another advantage of using the lowest possible rails is that the insulating coating products for fastening the rails have a high cost.
• the document FR 2 816 967 describes the use of a low rail for the construction of a tramway track.
• Document FR 2 852 978 gives another example of a low rail.
• These rails, used for the construction of tramway tracks comprise a lower part forming a pad, an intermediate portion forming the core of the rail, and in the upper part a mushroom and a bib, the mushroom and the bib defining a throat between them .
• the invention proposes to further reduce the depth of the engravures and thus the thickness of the channel slab.
• a method of constructing a railway which may comprise the steps of:
• each rail comprising a pad, surmounted by a mushroom and a flap, said mushroom and said flap delimiting between them a groove
• the method according to the invention uses rails that do not have a core so ultra-low, which allows use of shallower engravures and a slab lane less thick.
• the height of the rails may be less than or equal to half their width.
• the height of a rail is defined as the common height of the mushroom and the bib above the base of the pad if they have an identical height or the greatest height in the opposite case, and the width of the rail is defined as that of the rail pad.
• the method uses rails much lower than the known rails, their height being less than half their width, and preferably between 40 and 50% of this width.
• the foundation slab is made of concrete, it is possible to make a slab of track whose thickness is between 75% and 90% of the thickness of the foundation slab.
• the foundation slab is made of bituminous product, it is possible to make a slab of track whose thickness is between 2 and 3 times the thickness of the foundation slab.
• the bearing capacity of the soil must be at least 50 MPa.
• the method may comprise the prior step of pouring the foundation slab on a prepared floor.
• the foundation slab is provided. Otherwise the method comprises the step of producing this slab on a prepared floor.
• the thickness of the structure composed of the foundation slab and the slab of track may be between 35 and 50 cm.
• the method according to the invention makes it possible to gain in overall thickness of the structure, the structure being defined as the assembly consisting of the foundation slab and the track slab. The gain obtained is 15 to 20% in thickness with respect to a method of the state of the art.
• the track slab can be cast using a roller finisher, a slipform paver or a vibrating rule, depending on the possibilities and constraints of the worksites.
• a manual implementation can just as easily be used.
• the method may further comprise the step of performing a surface treatment on said channel tile, such as shot blasting, deactivation or printing.
• the method may further comprise the step of depositing a thin coating such as a surface coating or resin blocks on the track slab, or of disbursing the slab of track in order to lay pavers or topsoil for planting plants, including sod.
• a thin coating such as a surface coating or resin blocks on the track slab, or of disbursing the slab of track in order to lay pavers or topsoil for planting plants, including sod.
• the step of producing the engravures may comprise the steps of:
• the engravings are milled in the slab of road so that there remains, under the bottom of each engravure, a thickness of concrete superior to the depth of the engravure.
• An ultra-low, soulless rail will require a shallower engraving that will therefore be performed more quickly.
• the step of fixing a rail in each engravure may comprise the steps of:
• One solution to avoid stray currents is to weld rails and embed them in a non-conductive coating, such as a polyurethane resin.
• This coating also has the advantage, through an elastic load, for example cork or rubber, to filter the noise and vibrations caused by the passage of trains.
• this coating has a high cost.
• a soulless rail will require a smaller amount of potting compound.
• the rail is held and positioned in engravure very precisely, then the coating product is poured around and under the rail. Beforehand, a primer has been deposited on the walls and the bottom of the engravure, as well as on the rail.
• a template may be used to wedge the rail relative to the bottom and the walls of said engravure.
• the conventional method of setting the rail is to have shims at the bottom of the engravure, made of a material identical or similar to the coating product.
• the invention proposes to use a mobile template to very precisely place the two rails at a time, which provides a time saving.
• the insulating product may be a polyurethane resin, which may comprise an elastic load.
• the invention also relates to a railway track made using a method according to the invention.
• FIG. 1 schematically represents a tramway of the state of the art in cross-section
• FIGS. 2A and 2B schematically represent two embodiments of a tramway track according to the invention in cross-section
• FIG. 3 shows a soulless rail used in a tramway according to the invention in cross section.
• Figure 1 illustrates a state-of-the-art tramway track in cross-section with two rails.
• the track consists of a foundation slab 2 in concrete, scraped or not, cast on a floor 1; the thickness of this foundation slab depends on two parameters:
• the intensity of the expected traffic, counted in the passage of axles from 1 1 to 12 tons depending on the rolling stock during the lifetime of the track, is generally as a rule for 30 years.
• the foundation slab 2 will have a thickness of about 19 cm. If the floor has a bearing capacity of at least 50 MPa, it is also possible to make an asphalt foundation slab. In this case, it will have a smaller thickness, typically about 11 cm.
• the foundation slab 2 is surmounted by a slab of track 3 whose thickness depends little on the lift of the ground; it will be thicker if the foundation slab is made of bituminous product.
• the slab of track 3 comprises two longitudinal grooves 4a, 4b, each comprising a rail 10a, 10b, intended to be embedded in a product insulation inside its respective engravure.
• the product layer between the rail on the one hand and the walls and the bottom of the engravure on the other hand has a thickness of between 1.5 and 2.5 cm.
• the rails 10a, 10b are adapted to the circulation of trams, that is to say that they are asymmetrical: in addition to the mushroom, whose upper face constitutes the running surface of the rail, they comprise a flap, the mushroom and the bib delimiting between them a gorge. These rails also have a shoe which acts as a support for the rail, the mushroom assembly and bib being connected to the pad by a soul. This soul has a certain vertical extension: these rails typically have a height of about 15 cm. Consequently, the method of constructing the track comprises a step of producing engravings 4a, 4b which are sufficiently deep to receive this type of rail. The thickness of the slab of track 3 is therefore essentially conditioned:
• the height of the rails used thus significantly determines the overall thickness of the structure composed of the foundation slabs and track.
• FIGS. 2A and 2B illustrate a tramway track VI, also comprising two rail tracks, constructed according to the method of the invention, using soulless rails 11a, 11b which will be described in detail below.
• These rails have a much lower height than the rails of the state of the art, typically about 7 cm. Consequently the engravings 5a, 5b provided to receive these rails may be shallower and the track slab 3 less thick.
• the upper face 3a of the track slab 3 is in its entirety substantially at the height of the rail head 11a, 11b. This upper face can undergo a surface treatment such as deactivation, shot blasting or printing.
• the track slab 3 comprises disbursements 4a between the rails, and 4b, 4c on either side of the track VI. These disbursements make it possible to receive paving stones 6 or topsoil.
• Figure 3 illustrates a cross-section of a coreless groove rail 11 used in the invention.
• This rail comprises in the lower part a shoe 12 surmounted in the upper part of an assembly comprising a first transverse side a mushroom 13 and the opposite transverse side a flap 14, the mushroom 13 and the flap 14 defining between them an open groove 15 to the top.
• the pad 12 has a lower flat base 12a on which it rests in use, extended on each side by a transverse protuberance 12b and 12c. The distance between the ends of these transverse extensions of the pad defines the width L of the rail.
• the mushroom 13 has an upper surface 13a flat or substantially curved, and the flap 14 has an upper surface 14a flat or substantially curved.
• the upper surface 13a of the mushroom constitutes the running surface of the rail 11 intended to receive the tread of the wheels, the bead of the wheels circulating in the groove 15.
• the plane P which tangents these upper surfaces 13a and 14a is substantially parallel to the base 12a.
• the distance between this plane P and the base 12a defines the height H of the rail.
• the mushroom 13 and the flap 14 have an identical height H.
• the mushroom 13 and the flap 14 could have a different height; in this case, the height H of the rail is defined as the larger of the two.
• This rail 11 is characterized by a ratio HL less than 1 ⁇ 2.
• a rail of this type has for example a height of about 7 cm and a width of about 16 cm, a ratio of 0.4375.
• This type of grooved rail therefore has no intermediate body between the pad 12 and the assembly consisting of the mushroom 13 and the flap 14 which can be assimilated to a soul:
• the rail 11 is asymmetrical in the sense that:
• the mushroom 13 has a transverse dimension much greater than that of the flap 14; in the example cited above, the transverse dimension at mid-height L3 of the mushroom 13 is about 5.75 cm and that L4 of the flap 14 is about 3.1 cm;
• the walls of the groove 15 are not of the same shape: the wall 15a which constitutes the limit of the mushroom 13 is substantially rectilinear, the wall 15b which constitutes the limit of the flap 14 is curved, so that the throat itself is asymmetrical.

Landscapes

• Engineering & Computer Science (AREA)
• Architecture (AREA)
• Civil Engineering (AREA)
• Structural Engineering (AREA)
• Mechanical Engineering (AREA)
• Road Paving Structures (AREA)
• Machines For Laying And Maintaining Railways (AREA)

Applications Claiming Priority (2)

Publications (2)

Family

ID=48577116

Family Applications (1)

Country Status (5)

Citations (3)

Family Cites Families (3)

• 2012
  • 2012-05-16 FR FR1254488A patent/FR2990704B1/fr active Active
• 2013
  • 2013-05-13 DK DK13727273.8T patent/DK2850249T3/en active
  • 2013-05-13 EP EP13727273.8A patent/EP2850249B1/de active Active
  • 2013-05-13 BR BR112014028200A patent/BR112014028200A2/pt not_active Application Discontinuation
  • 2013-05-13 WO PCT/FR2013/051034 patent/WO2013171412A2/fr active Application Filing

Patent Citations (3)

Non-Patent Citations (1)

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