JPH0415761Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field] The present invention relates to the improvement of cushioning materials under railway trackbeds.

Tracks with concrete foundations are used for railways such as the Shinkansen. On such tracks, ballast pine is laid on the foundation concrete, ballast is loaded on top of the ballast pine, and sleepers are placed on top of the ballast pine to reduce vibration noise and wheel load fluctuations caused by running trains. However, there is a tendency for tracks that fix the rails to these sleepers to be used frequently. The underbed cushioning material of the present invention is used as such a ballast mat.

[Prior art]

As such a ballast mat, a rubber sheet having a thickness of about 25 mm, a width of 500 mm, and a length of about 2000 mm is conventionally used. In order to apply compressive displacement in the thickness direction, a large number of spaces are formed in the ballast pine, and the displacement of the ballast pine is absorbed by the spaces.

[Problem that the invention attempts to solve]

In such conventional ballast pine, the ballast pine is compressed and deformed in the thickness direction every time a train passes on the track, so the space formed inside the ballast pine or between the ballast pine and the concrete floor becomes small. Become. That is,
Each time a train passes, the space in the ballast pine becomes smaller, and when a train passes, the compressive force is released and the space becomes larger. For this reason, it is predicted that the air filling the space will move in and out, and the pumping action of this air will suck rainwater into the space, or dirt and the like along with the rainwater, filling the space with dirt and the like. If the space is filled with earth and sand, etc., there is no space to absorb the compression displacement due to the compression in the thickness direction of the ballast pine, so the ballast pine will not be compressed, and the ballast pine will not be compressed. The effects of reducing vibration and noise during train running are virtually lost.

The object of the present invention is to provide an under-trackbed cushioning material that can reduce vibration and noise caused by train running for a long period of time without the inflow of earth and sand.

[Means for solving problems]

The under-track cushioning material of the present invention is composed of a large number of wall-shaped support parts arranged parallel to each other at intervals, and an upper plate part that integrally connects the upper ends of the support parts,
A plate-shaped solid part made of highly elastic rubber having a long groove between the mutually adjacent supporting parts, and a solid part embedded in and fixed to the openings at both ends of the long groove to close the openings at both ends of the long groove, and having a flat lower end surface. It is characterized by comprising a plug part that is softer than the support part and is formed at the same level as the lower end surface of the support part.

The under-track cushioning material of the present invention is formed between the supporting parts by closing both ends of the long groove formed between the supporting parts constituting the solid part with plug parts, and laying this under-track cushioning material on the base. The space is sealed from the outside using a stopper and a base. Therefore, even if the under-road bed cushioning material undergoes repeated compressive deformation and recovery, there is little risk of dirt or the like flowing into the space within the under-road bed cushioning material from the outside.

[Detailed explanation of the structure of the invention]

The underbed cushioning material of the present invention is composed of a solid part made of highly elastic rubber and a plug part.

The solid part made of high elastic rubber consists of a wall-shaped support part which is arranged parallel to each other at many intervals and in the form of a plane as a whole, and an upper plate part which integrally connects the upper end of the support part. It is a plate-like structure. The thickness or thickness of the support parts, the space between the support parts, the elastic modulus of the solid part, etc. can be selected from various values depending on the purpose. Note that the solid portion here includes the meaning of a solid member rather than a porous body.

The support part constituting this solid part substantially receives the compressive force acting on the underbed cushioning material, and is compressed in the thickness direction by the compressive force, and the support part itself reduces its height and its thickness and thickness. By increasing the displacement, compressive displacement is possible. Note that the wall-like support portion may have cuts in a direction different from its longitudinal direction. When the wall-like support portion is fragmented by the cuts, these fragments form a columnar shape. The upper plate section, which is another component of the solid section, converts the pressure acting from above the under-track cushioning material into a compressive force in the height direction of the support section (corresponding to the thickness direction when viewed from the entire under-track cushioning material). It transmits power. Therefore, it is preferable that the upper plate portion be relatively thick. or,
It is preferable that the portion of the upper plate portion that is in contact between the supporting portions has a thicker wall thickness than the upper portion of the supporting portion.

The solid parts can be made from conventional natural rubber, synthetic rubber, or recycled rubber.

The plug portion fills the space between the adjacent support portions of only the opposing end surfaces of the solid portion, and forms a groove in the solid portion with both ends closed. The plug part is not made of the same material as the solid part, but is made of a soft porous body. If it is made of a soft porous material,
Since it is easily compressed and contracted, it has the same effect as the space formed between the support parts, which is preferable. As the soft porous material, a closed cell material is particularly preferable. For this reason, it is preferable to construct the stopper portion with a foam such as a soft urethane foam or a polyethylene foam.

The solid portion and the plug portion are integrally formed or joined.

[Effect of idea]

The under-track cushioning material of the present invention has a plate-like overall shape. In addition, a large number of grooves with both ends closed are provided in parallel on the lower surface of the under-track bed cushioning material. Therefore, even if the volume of the space in the groove in the under-bed cushioning material changes due to compressive deformation of the under-bed cushioning material, the inflow of earth and sand is prevented by the plugs provided at both ends of the groove. Therefore, the compressive deformation of the under-track cushioning material is maintained for a long period of time. Therefore, vibrations and noise caused by running trains can be effectively absorbed for a long period of time by the under-track cushioning material of the present invention. Moreover, since the plug part is soft, the elasticity of each part of the solid part does not vary.

〔Example〕

FIG. 1 shows a partial perspective view of an under-track cushioning material A according to an embodiment of the present invention. This under-track cushioning material A is composed of a solid portion 1 and a plug portion 2. The solid portion 1 is a relatively thick upper plate portion 1 that integrally connects a large number of partition-like support portions 11 and the upper end portions of each support portion 11.
It is composed of 2. A long groove 1a is formed between each adjacent support part. Further, a relatively shallow recess 12a is formed on the upper surface of the upper plate part 12 and in a portion corresponding to the upper part of the support part 11, and the thickness of the upper plate part 12 becomes thinner above the support part 11.

The plug portion 2 is located only at opposite ends of the solid portion 1, and is located between the long grooves 1a formed between the wall-shaped support portions 11.
are joined with both ends closed.

This solid portion 1 is integrally formed entirely of synthetic rubber, and its compressive elastic modulus is relatively high. The plug part 2 is made of polyethylene foam, and the solid part 1 and the plug part 2 are integrally bonded with adhesive adhesive.

FIG. 2 shows a cross section of this under-track cushioning material A laid on the base B. The long groove 1a formed below the under-track cushioning material A is surrounded by the solid portion 1, the plug portions 2 on both sides, and the base B, forming a sealed space. Therefore, earth and sand cannot flow into the long groove 1a.

[Brief explanation of the drawing]

FIG. 1 is a partial perspective view showing an under-track cushioning material according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of the under-track cushioning material shown in FIG. 1 placed on a base. A...Buffer material under the track bed, B...Base, 1...Solid part, 2...Plug part, 1a...Long groove.

Claims (1)

[Claims for Utility Model Registration] (1) Consisting of a large number of wall-shaped support parts arranged parallel to each other at intervals, and an upper plate part that integrally connects the upper ends of the support parts, a plate-shaped solid part made of highly elastic rubber having a long groove between the adjacent supporting parts; embedded and fixed in the openings at both ends of the long groove to close the openings at both ends of the long groove; An under-track bed cushioning material comprising a plug part that is softer than the support part and is formed at the same level as the lower end surface of the support part. (2) The under-track cushioning material according to claim 1 of the utility model registration claim, wherein the plug part is a soft porous material. (3) The under-track cushioning material according to claim 1, wherein the plug portion is made of closed-cell soft resin or rubber.