DE19881823B4 - Cross sleeper for railway tracks - Google Patents

Abstract

The invention relates to a railway sleeper (12) consisting of rails placed on top of a bed of road metal. The underside of said sleeper is provided with a plastic deformable coating (22) increasing the stability of the track layer and reducing damage to the bed of road metal.

Description

The The invention relates to a sleepers for railway tracks made of concrete, Reinforced concrete or steel, as related to on a ballast bed Overlying track grids are used in railway superstructure.

The Cross sleeper as a component in the railway superstructure takes from the Traffic loads emanating from the forces Rail and the intermediate layers with the bracing elements in the bases the sleeper bearing and the forces introduced derived to the underlying ballast scaffolding load distribution and forwarded to the substructure or subsoil.

since Beginning of the railway age in the past century used as sleepers wooden sleepers. In the time of industrialization and as a barometer of the steel industry were also steel sleepers produced and installed, in recent times also as "Y-threshold". Since the 50s Prestressed concrete sleepers were increasingly used in this century which have currently prevailed as state of the art.

The et al from ecological establish scarcely used wooden threshold had the advantage among other things to be considered "elastic". one the reasons for that is the teeth of the comparatively soft wooden threshold underside with the hard stone gravel.

In contrast, have the concrete sleeper and the comparable steel sleeper in this context the disadvantage that in contrast to the wooden threshold, on the support surface of the threshold on the gravel two inelastic materials meet, so the above mentioned Gearing not possible is, so that the Recording of longitudinal and transverse forces is reduced by the ballast bed. Furthermore, the lead hard, inelastic contact points between ballast and sleeper in case of overuse to damage or destruction the threshold or the gravel.

In order to avoid overuse of the ballast, especially in fast-driving routes, it has already been proposed to coat the threshold underside with an elastic, polymeric material in order to achieve cushioning and thus to relieve the ballast pressure. An appropriate track is for example on DE 691 13 884 T2 known. By using such an elastic intermediate layer between ballast and concrete sleeper, although the ballast bed can be spared, but on the other hand, the longitudinal and transverse displacement resistance forces are considerably reduced, so that the positional stability of such tracks is still less than that of tracks in which the concrete sleepers directly on the Resting ballast bed.

Of the The invention is therefore based primarily on the object, a Threshold to create, with the positional stability of the track can be increased and at the same time damage of the ballast bed is avoided.

These Task is inventively characterized solved, that the Cross sleeper on its underside, in particular in the area of their supports is provided with a plastically deformable coating.

by virtue of the plastically deformable coating of the threshold underside Due to the plastic deformation of the coating a "toothing" of the threshold with scored the ballast, whereby on the one hand the transverse displacement resistance and the longitudinal displacement resistance the track rust significantly increased and thus the positional stability of the track is significantly improved. Furthermore, this will achieved that on the one hand peak pressures degraded and edge pressures are reduced and on the other hand, that the contact area between gravel and threshold is increased, so that the surface pressures across from The prior art can be reduced and material destruction reduced or excluded. Finally, the one with the Coating achieved "softness" of the contact area between gravel and threshold material-friendly.

In preferred development of the invention, the plastically deformable Consist essentially of a tar / asphalt mixture coating, which is a particularly cost-effective Solution is. Alternatively, the coating may consist essentially of a plastic, wood concrete, wood or wood shavings.

Already for cost reasons it may be appropriate the plastically deformable coating exclusively in Form area of the support of the sleepers, so that the bearing free Zones remain uncoated.

The Thickness of the coating may be comparatively thin, i. less than 10mm and may in particular be about 5 mm. Furthermore, the bottom can The coating will be profiled to an even better anchorage to achieve the sleepers on the ballast bed.

Although the Beschich tion of the sleepers can optionally also be retrofitted to the thresholds, it is preferred to integrate the application of the coating in the manufacturing process of concrete sleepers to ensure the best possible bond. For this purpose, the coating can be applied in particular as a final operation when casting the threshold on the corresponding areas of the threshold underside. Alternatively, the coating could also be subsequently glued to the threshold underside.

in the The following will be an embodiment of Invention with reference to the drawing explained. In show the drawing:

1 a vertical section through a track in a plane parallel to the rails,

2 a plan view of the track according to 1 .

3 a horizontal section through the track according to 1 perpendicular to the longitudinal direction of the rails, and

4 an enlarged sectional view in the region of a threshold.

In the figures, the reference numeral 10 a ballast bed, with the reference number 12 In the ballast bed arranged sleepers, with the reference numeral 14 arranged on the sleepers rails and the reference numeral 16 referred to a guided on the rails wheel. Between rail 14 and sleepers 12 are the usual liners 18 arranged. The ballast bed 10 lies on a plane 20 on. In that regard, this structure of a railway track corresponds to the conventional structure and requires no further explanation.

At the bottoms of the sleepers 12 are plastically deformable coatings 22 trained, and how, how 2 and 3 is recognizable, such that the bearing-free areas 24 the sleepers 12 are coating-free. It should be noted that the hatches in 2 those areas of (in 2 not visible) threshold underside to mark, on which a coating is provided. The arrows 26 and 28 in the 1 to 3 should indicate the transverse or longitudinal forces occurring in the track.

The detailed representation according to 4 illustrates the interlocking of the stones of the ballast bed with the plastically deformable coating 22 , Firstly, it is immediately clear that the displacement forces increase significantly due to the teeth, on the other hand is readily apparent that the contact surface of the threshold underside with the ballast bed is now greatly increased, so that the forces occurring between the contact surfaces per unit area significantly reduced overall become.

• – anstelle einer wie beim Stand der Technik vorhandenen punktuellen Kraftübertragung zwischen Schwelle und Schotter nunmehr eine flächenmäßige Kraftübertragung erfolgt,
• – Spitzendrücke auf einzelne Schottersteine abgebaut und die Kantenpressungen verkleinert werden,
• – hierdurch eine Zertrümmerung der Schottersteine bzw. eine Beschädigung der Betonschwelle vermieden wird, und
• – aufgrund der Verzahnung des Schotterbetts an der plastisch deformierbaren Beschichtung der Querschwellen eine Erhöhung der Längs- und Querverschiebewiderstände auftritt, wodurch die Lagestabilität des Gleises verbessert wird.

The advantages achieved by the invention are therefore in particular that

• Instead of a point-like force transmission between threshold and gravel, as in the prior art, an area-based force transmission now takes place,
• - reduced peak pressures on individual ballast stones and the edge pressures are reduced,
• - This is a destruction of the ballast stones or damage to the concrete sleeper is avoided, and
• - Due to the toothing of the ballast bed on the plastically deformable coating of the sleepers an increase in the longitudinal and lateral displacement resistance occurs, whereby the positional stability of the track is improved.

10

ballast

12

sleepers

14

rails

16

wheel

18

interim storage

20

Planum

22

coating

24

auflagerfreie areas

26

transverse forces

28

longitudinal forces

Claims (8)

Cross sleeper for railway tracks of concrete, reinforced concrete or steel, with a plastically deformable coating ( 22 ) on its underside. A tie according to claim 1, characterized in that the plastically deformable coating ( 22 ) is mounted only in the area of the support of the sleepers. A tie according to claim 1 or 2, characterized in that the coating ( 22 ) consists essentially of a tar / asphalt mixture. A tie according to claim 1 or 2, characterized that the Coating consists essentially of a plastic. A tie according to claim 1 or 2, characterized in that the coating ( 22 ) in the essentially made of wood or wood-concrete or wood shavings. A tie according to one of the preceding claims, characterized in that the underside of the coating ( 22 ) is profiled. A tie according to one of the preceding claims, characterized in that the coating ( 22 ) is formed as a coating applied in the production process of the cross sleeper. Railway track with a ballast bed ( 10 ) and a track grid resting on the ballast bed, characterized by sleepers ( 12 ) according to any one of the preceding claims.