BALLASTLESS TRACK SECTION FOR A RAIL VEHICLE

Abstract

The invention relates to a ballastless track section for a rail vehicle, said section being fastened to a platform (10) and comprising: a prefabricated concrete track slab (20, 120) comprising two stringers (21, 22); a rounded bearing surface (21c, 22c) borne by an underside of each stringer at each longitudinal end and having a curvature, the center of curvature of which is the top of a rail (21b, 22b) borne by the stringer; a prefabricated support pad (30, 130) for supporting each longitudinal end of the slab (20, 120) and comprising at least two support bases (33, 34) for the two stringers of this longitudinal end of the slab, each base (33, 34) comprising at least one shim (33a, 34a) of predetermined thickness supporting said rounded bearing surface (21c, 22c) of the stringer of said slab facing this base.

Claims

1. A ballastless track section for a rail vehicle intended to be fastened on a track platform, wherein said track section comprises: a prefabricated concrete track slab comprising two stringers extending along a longitudinal direction and, at each longitudinal end of the slab, a notch separating said stringers so as to form an H-shaped track slab; for each stringer, a plurality of transverse supporting blocks for maintaining a longitudinal rail and mounted on an upper face of said stringer, and at each longitudinal end of the stringer, a rounded bearing surface borne by an underside of said stringer and having a curvature whose center of curvature is the top of said rail; for each longitudinal end of said slab, a prefabricated support pad of at least this longitudinal end of the slab, said prefabricated support pad comprising a plate and a longitudinal central block projecting from said plate intended to extend into the notch of this longitudinal end of said slab, once this slab is mounted on this pad, and delimiting, on either side of said central block, at least two support bases for the two longitudinal stringers of this longitudinal end of said slab, each base comprising at least one shim of predetermined thickness arranged on said plate and intended to support said rounded bearing surface of the stringer of said slab facing this base, once this slab is mounted on said pad; for each support pad, foundation means for this support pad in said track platform.

2. The track section according to claim 1, wherein at least one pad comprises, on either side of the central block, two support bases for two stringers separated by a transverse stiffening wall, so that this pad can support two longitudinal ends of two consecutive slabs.

3. The track section according to claim 1, wherein said central block of at least one pad comprises at least one longitudinal stop borne by a longitudinal wall of said central block so as to be able to block any longitudinal displacement of the slab whose notch receives this longitudinal wall of the central block.

4. The track section according to claim 1, wherein said central block of at least one pad comprises at least one lateral stop mounted on a side wall of said central block so as to be able to block any lateral displacement of the slab, the notch of which receives this side wall of the central block.

5. The track section according to claim 4, wherein said central block of at least one pad comprises at least one adjustable lateral stop so as to be able to define the lateral space that separates said central block from each slab borne by this pad.

6. The track section according to claim 1, wherein said bases of the shims of at least one pad are inclined toward said central block to allow better stability of each slab borne by this pad.

7. The track section according to claim 1, wherein said slab further comprises, at each longitudinal end, on either side of said notch, at least one threaded insert (27a, 27b) arranged in said slab and emerging facing said plate of the pad bearing this end of the slab, once the slab is mounted on said pad, so as to allow vertical lifting of said slab relative to the pad by screwing a lifting screw into said insert that bears against said plate of said pad.

8. The track section according to claim 1, wherein at least one pad comprises, on either side of the central block, two support bases for two stringers separated by a transverse wall, so that this pad can support two longitudinal ends of two consecutive slabs.

9. The track section according to claim 1, wherein said foundation means for at least one pad in said track platform comprise at least one pile per stringer support base.

10. The track section according to claim 1, wherein said rounded bearing surfaces of said longitudinal stringers of said slab are formed from an elastomer.

11. The track section according to claim 1, wherein said shims of predetermined thickness arranged on said plate of said pad are made of steel.

12. A ballastless track for a rail vehicle comprising a track platform and a plurality of track sections successively fastened to said track platform, the track sections comprising: a prefabricated concrete track slab comprising two stringers extending along a longitudinal direction and, at each longitudinal end of the slab, a notch separating said stringers so as to form an H-shaped track slab; for each stringer, a plurality of transverse supporting blocks for maintaining a longitudinal rail and mounted on an upper face of said stringer, and at each longitudinal end of the stringer, a rounded bearing surface borne by an underside of said stringer and having a curvature whose center of curvature is the top of said rail; for each longitudinal end of said slab, a prefabricated support pad of at least this longitudinal end of the slab, said prefabricated support pad comprising a plate and a longitudinal central block projecting from said plate intended to extend into the notch of this longitudinal end of said slab, once this slab is mounted on this pad, and delimiting, on either side of said central block, at least two support bases for the two longitudinal stringers of this longitudinal end of said slab, each base comprising at least one shim of predetermined thickness arranged on said plate and intended to support said rounded bearing surface of the stringer of said slab facing this base, once this slab is mounted on said pad; for each support pad, foundation means for this support pad in said track platform.

Description

LIST OF FIGURES

[0061] Further aims, features and advantages of the invention will become apparent upon reading the following description, which is provided solely by way of a non-limiting example, and which refers to the accompanying figures, in which:

[0062] FIG. 1 is a schematic perspective view of a track section according to one embodiment of the invention;

[0063] FIG. 2 is a detailed schematic view of a pad and a longitudinal end of a track slab of the track section of FIG. 1;

[0064] FIG. 3 is a schematic side perspective view of the pad of FIG. 2;

[0065] FIG. 4 is a schematic side view of the pad of FIG. 3 further comprising means for lifting the track slab;

[0066] FIG. 5 is a schematic profile view of a track section according to one embodiment of the invention.

DETAILED DESCRIPTION OF ONE EMBODIMENT OF THE INVENTION

[0067] For the sake of illustration and of clarity, the scales and the proportions are not strictly adhered to in the figures. Throughout the following detailed description with reference to the figures, unless otherwise indicated, each element of a track section is described as it is arranged when the track section is anchored in a platform to form a running track of a rail vehicle. This configuration is shown in particular in FIG. 1.

[0068] The terms longitudinal, transverse and vertical are used in a non-limiting manner with reference to the trihedron L, T, V as shown in FIG. 1. The longitudinal direction corresponds to the direction of the rails of the track section and defines the direction of displacement of a rail vehicle using this track section. The vertical direction is the direction defined by the gravity of the installation site of the track section. The transverse direction is the direction perpendicular to the longitudinal direction and to the vertical direction.

[0069] Moreover, identical, similar or analogous elements are denoted using the same reference signs throughout the figures.

[0070] FIG. 1 schematically illustrates a track section according to one embodiment of the invention comprising a prefabricated concrete track slab 20 (also referred to using the term “track panel”) and two pads 30, 130 arranged at each of the longitudinal ends 20a, 20b of the track slab 20. FIG. 1 also illustrates a portion of a second track slab 120, one longitudinal end of which rests on the pad 130, with the other longitudinal end of this second slab 120 resting on another pad not shown in FIG. 1.

[0071] Throughout the following, the same reference signs are used for the constituent elements of the slabs 20, 120 and of the pads 30, 130 for the sake of clarity and insofar as the features of the two pads and of the two slabs are identical.

[0072] The prefabricated concrete track slab 20 comprises two stringers 21, 22, which each extend along the longitudinal direction L. The slab 20 further has a notch 23, 24 at each of its longitudinal ends 20a, 20b. Thus, the slab 20 is generally H-shaped.

[0073] Each stringer 21, 22 also bears a plurality of transverse supporting blocks 21a, 22a for maintaining a longitudinal rail 21b, 22b. The supporting blocks 21a, 22a are for example formed from concrete and sealed in the track slab 20. The means for supporting the rails 21b, 22b can be of any type and are not described in detail herein.

[0074] Each stringer also comprises, at each of its longitudinal ends, and as shown in FIGS. 3 and 5, a rounded bearing surface 21c, 22c, for example made of elastomer, borne by an underside of the stringer. This rounded bearing surface 21c, 22c has a curvature whose center of curvature is the top of the rail 21b, 22b borne by this stringer.

[0075] In other words, the geometry of the rounded bearing surface 21c, 22c (and in particular its curvature) depends on the thickness of the slab, the height of the supporting blocks and the height of the rails borne by the supporting blocks so that, once these various elements are assembled, the center of curvature of the rounded bearing surface 21c, 22c coincides with the top of the rail 21b, 22b.

[0076] Each rounded bearing surface 21c, 22c rests on a stack of shims 33a, 34a, formed for example from steel. The height of the shims or the number of shims (in the case where the shims have identical thicknesses) make it possible to adjust the height and the cant of the track section.

[0077] The shims 33a, 34a rest on bases 33, 34. These bases 33, 34 are formed on a plate 31 of the pad and are separated from each other by a longitudinal central block 32. The plate 31 has the general shape of a truncated V, whereof the branches of the V form the bases inclined toward the longitudinal central block 32, which stands at the center of the truncated V.

[0078] Each branch of the truncated V preferably extends parallel to the lower surface of the stringer, which bears the rounded bearing surface arranged opposite the base formed by this branch of the truncated V.

[0079] The base 33 receives the stack of shims 33a on which the bearing surface 21c of the stringer 21 bears. The base 34 receives the stack of shims 34a on which the bearing surface 22c of the stringer 22 bears.

[0080] According to the embodiment of the figures, each pad 30, 130 comprises, on either side of the central block 32, two support bases for two stringers separated by a transverse wall 37, 38, so that this pad 30, 130 can support two longitudinal ends of two consecutive slabs. In other words, a pad according to the embodiment of the figures supports the two adjacent longitudinal ends of two consecutive track slabs. Each pad 30, 130 has, according to the embodiment of the figures, a symmetry with respect to a transverse plane (except for the heights of the shims, which can be different on either side of the plane of symmetry insofar as the adjustment of the two consecutive track slabs can be different from one slab to another).

[0081] Throughout the following, the same reference signs are used for each element on either side of this transverse plane of symmetry.

[0082] As shown in particular in FIG. 2, the central block 32 of the pad 30 also comprises two longitudinal walls 32a, 32b and two side walls 32c, 32d. Each longitudinal wall 32a, 32b further comprises a longitudinal stop 35a, 35b. Each longitudinal stop 35a, 35b is for example formed from an elastomer. It can for example be slidably mounted in a groove formed on the longitudinal wall 32a, 32b of the central block. These longitudinal stops make it possible to prevent any longitudinal displacement of the slab 20.

[0083] In addition, each side wall 32c, 32d comprises two lateral stops 36a, 36b, which extend into each notch of the slab 20. These lateral stops 36a, 36b are formed for example from elastomer and make it possible to prevent any lateral displacement of the slab relative to the pad 30.

[0084] According to the embodiment of the figures, each lateral stop 36a, 36b is formed by a threaded rod configured to be able to be screwed into an internal thread formed in the side wall 32c, 32d of the central block so as to be able to define the distance that separates the central block 32 from the slab 20.

[0085] As illustrated schematically in FIGS. 2, 4 and 5, the track section preferably comprises, at each longitudinal end 20a, 20b of the slab 20, 120 on either side of the notch 23, 24 arranged at this end, a threaded insert 27a, 27b arranged in the slab 20, 120 that opens out facing the plate 31 of the pad 30, 130. Each insert 27a, 27b is configured to be able to receive a lifting screw 28, which, once screwed, bears against the plate 31 of the pad 30, 130, which causes a vertical displacement of the slab 20 relative to the pad 30 anchored in the platform.

[0086] In other words, the combination of the threaded insert 27a, 27b and the lifting screw 28 allows means to be formed for vertically lifting the slab 20 relative to the pad 30. This particularly allows the shims 33a, 34a to be inserted in order to adjust the orientation and the position of the slab 20.

[0087] FIG. 5 schematically illustrates how a track section according to the invention can be adjusted. In particular, if during the initial adjustment of the track or following compaction of the ground, the geometry of the track section must be corrected, the invention makes it possible to modify the orientation of the slab, without destroying the track and without particular difficulties.

[0088] In particular, it is considered that the initial adjustment of the track consisted in arranging shims 33a, 34a, which respectively have heights H1 and H2, under the rounded bearing surfaces 21c, 22c.

[0089] The particular structure of the track section according to the invention allows the following adjustments to be made: [0090] adding a shim of thickness e on each of the two shims 33a, 34a (after lifting the slab 20 by means of the lifting screws 28 inserted into the inserts 27a, 27b) allows the slab 20 to be raised in the vertical direction by a height e; [0091] replacing the shims 33a, 34a with shims with respective thicknesses H1-e and H2-e (after lifting the slab 20 by means of the lifting screws 28 inserted into the inserts 27a, 27b) allows the slab to be lowered in the vertical direction by a height e; [0092] adding a shim of thickness e on the shim 33a and replacing the shim 34a with a shim H2-e allows the slab 20 to laterally displace by a distance e to the left of FIG. 5; [0093] adding a shim with thickness e on the shim 34a and replacing the shim 33a with a shim of thickness H1-e allows the slab 20 to laterally displace by a distance e to the right of FIG. 5; [0094] adding a shim of thickness e on the shim 34a, without modifying the shim 33a, allows the slab 20 to be pivoted with respect to a longitudinal axis in order to form a cant to the left of FIG. 5; [0095] adding a shim of thickness e on the shim 33a, without modifying the shim 34a, allows the slab 20 to be pivoted with respect to a longitudinal axis in order to form a cant to the right of FIG. 5.

[0096] Thus, a pad of a track section according to the invention makes it possible to adjust the orientation of the slab simply with a minimum amount of standardized parts.

[0097] In the case of the construction of a new track or of the regeneration of a track, the invention allows the geometry of the track (height and cant) to be defined through the successive adjustment of the various pads supporting the various successive slabs of the track, following the installation of the various pads and of the various slabs on the pads.

[0098] In addition, with each slab resting on two successive pads, this frees up a space between the platform and the slab, which allows rainwater to flow under the slabs if necessary and allows insects and other amphibians living in the vicinity of the track to travel under the track. A track according to the invention is therefore more respectful of the ecosystem than the tracks of the prior art.

[0099] The invention is not limited to only the embodiments described with reference to the figures. In particular, a pad of a track section according to the invention can form the bearing surface of only one longitudinal end of a track slab and not of two longitudinal ends of two successive slabs as illustrated in the figures. Where applicable, the installation of a track requires twice as many pads, on an equivalent track, as the installation of the track for which each pad allows the two longitudinal ends of two successive slabs to be supported.