JPH07138902A - Sleeper - Google Patents

Abstract

PURPOSE:To provide a sleeper which can be applied even to a place where depth of ballast can not be easily ensured, while depth of ballast can be reduced, and strength and lateral resistance of the sleeper can be ensured. CONSTITUTION:The height of a side board 24 of a hollow, box-shaped sleeper 10, the bottom of which is open and into which ballast can be filled, is made as low as possible to a such a degree that may not impair the strength of the sleeper by making larger the thickness of an upper board 22 and the side board 24. A plurality of protrusions 32 are projected downwardly, in a spaced apart relationship, from the lower end of the side board 24 of the sleeper 10 to generate lateral resistance.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sleeper, and more particularly to a hollow box-shaped sleeper having an open bottom.

[0002]

2. Description of the Related Art Conventionally, a railroad track has a roadbed formed by ballast of gravel, crushed stone, etc. on a roadbed, sleepers are buried in the roadbed, and a pair of rails are laid on the railroad track. The sleepers are generally made of wood or concrete. These conventional sleepers are formed to have a certain thickness or more in order to secure their strength.

[0003]

[Problems to be Solved by the Invention]
There are places where it is difficult to secure the thickness of the roadbed. For example, when installing overhead lines to electrify an existing unelectrified tunnel, or when vehicles passing through this tunnel grow in size, avoid re-digging the tunnel, or To minimize this, it is common practice to reduce the thickness of the bed. Also on the culvert, etc., it is often difficult to ensure the thickness of the track.

However, in the railroad track, it is necessary to secure a ballast layer having a constant thickness under the sleepers.
In addition, the sleepers themselves need to have a certain thickness or more because of the demand for strength and lateral resistance. Therefore, there is a problem in that the road bed thickness cannot be simply reduced with the conventional configuration.

Therefore, an object of the present invention is to solve the above problems and to provide a sleeper which can reduce the thickness of the roadbed and can secure the strength and lateral resistance of the sleeper main body.

[0006]

In order to achieve the above object, the present invention requires the height of a peripheral side plate of a hollow box-shaped sleeper body whose bottom is opened and can be filled with ballast from the viewpoint of strength. It is formed to be as low as possible and is provided with a toothless projection projecting downward at the lower end of the peripheral side plate of the sleeper body.

[0007]

With this structure, the sleeper main body has the necessary strength, and the height of the side plate of the sleeper main body, that is, the thickness of the sleeper main body is made as small as possible to secure the thickness of the roadbed. It is easy to apply even in places where it is difficult to do so, and by filling the interior of the hollow box shape with an open bottom with ballast, a ballast layer is also formed inside the sleeper body, and this sleeper body is practically used. The thickness of the roadbed can be reduced by just that much. Furthermore, the tooth-shaped projections protruding downward from the lower edge of the side plate of the sleeper main body mesh with the ballast to reduce the substantial thickness of the sleeper main body, but the required lateral resistance force is reduced. Reserved.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. 1 to 4, reference numeral 10 denotes a sleeper body, which is formed in a hollow box-like shape with an open bottom and is made of a metal material such as ductile cast iron. The sleeper main body 10 can support the pair of rails 14 by the rail support portions 12 formed near both ends thereof, and the hole portions of the pair of shoulder portions 15 formed in the rail support portions 12 respectively. Each rail 14 can be fastened by a pan roll clip 18 attached to 16.
An insulating pad 20 is interposed between the rail 14 and the support portion 12.

The box-shaped sleeper main body 10 has an upper plate 22 and side plates 24 swirled around the periphery. The upper plate 22 defines the width of the sleeper main body 10, and the side plates 24 define the sleeper main body. A height or thickness of 10 is defined. The ratio of the height to the width of the sleeper body 10 is 1
The height of the side plate 24 is set as low as necessary for strength so as to be 5 to 30%. Specifically, the conventional sleeper has a thickness of 140 to 260 mm, while the sleeper body 10 shown has a thickness of 50 to 100 mm.
It is set to about mm. Further, a thick portion 26 for reinforcement is formed at the hem edge of the side plate 24. Corresponding to the reduction of the thickness of the sleeper body 10 in this way,
The plate thicknesses of the upper plate 22 and the side plates 24 are set large enough to obtain the required strength and weight of the sleeper main body 10.

The central portion 28 of the sleeper main body 10 between the pair of rail supporting portions 12 is formed narrower than the rail supporting portions 12, and as a result, the central portion 28 and the rail supporting portion 12 are separated from each other. An end surface 30 for generating lateral resistance is formed at the boundary. Further, a plurality of toothless protrusions 32 for lateral resistance generation are integrally formed at the lower end of the side plate 24 in the peripheral portion so as to project downward so as to be able to mesh with and engage with the ballast. It has a sleeper structure.

According to this structure, the sleeper body 1
With 0, the thickness can be made as small as possible while securing the necessary strength that can resist bending and deformation due to wheel load as described above. In addition, sleeper body 1
By filling the ballast 34 inside 0, the ballast layer is also formed inside the sleeper body 10. That is, the ballast layer can be formed not from the lower end of the sleeper body 10 but from the inner surface of the upper plate 22 thereof. for that reason,
Even if the ballast layer, that is, the thickness of the track bed is reduced by the substantial thickness of the sleeper body 10 excluding the thickness of the upper plate 22,
As shown in FIG. 3, the lower ballast layer of the sleeper body 10 can be maintained at a predetermined thickness T.

Therefore, by adopting such a roadbed structure having a smaller thickness than that of the conventional one, when installing an overhead line for electrifying an existing unelectrified tunnel, or a vehicle passing through this tunnel becomes large in size. Even in a case where it is difficult to secure the thickness of the roadbed, as in such a case, it is possible to easily apply the method and avoid re-digging the tunnel. Even if excavation is absolutely necessary, the amount of excavation can be minimized. Moreover, even if lateral pressure is generated on the sleepers due to the passage of the vehicle, especially in curved sections,
As described above, by increasing the plate thickness of the sleeper body 10 to increase the weight, and by the end face 30 for generating lateral resistance and the plurality of toothless projections 32 protruding downward, Despite the reduced thickness and reduced pressure-receiving area, the required lateral resistance can be secured.

[0013]

As described above, according to the present invention, the height of the peripheral side plate of the sleeper body is formed as low as necessary for strength, and the lateral resistance from the lower end of the peripheral side plate of the sleeper body is increased. Since the toothless protrusion for generation is projected downward, the thickness of the sleeper body is made as small as possible, and the ballast layer is also formed inside the sleeper body. The thickness can be reduced, and the required lateral resistance can be secured even though the thickness of the sleeper body is reduced.

[Brief description of drawings]

FIG. 1 is a partially cutaway front view of a sleeper according to an embodiment of the present invention.

2 is a plan view of the sleeper of FIG. 1. FIG.

3 is a cross-sectional view of the sleeper of FIG.

FIG. 4 is a schematic perspective view of the sleeper of FIG. 1.

[Explanation of symbols]

 10 sleeper body 24 side plate 32 toothless protrusion 34 ballast

Claims (1)

[Claims] 1. A hollow box-shaped sleeper body having an opening at the bottom which can be filled with ballast, has a peripheral side plate formed to have a height as low as necessary for strength, and the sleeper body has a lower height. A sleeper having a toothless protrusion protruding downward at the lower end of the peripheral side plate.