How to build slab track

Abstract

To provide a slab track construction method which, during the slab track construction, prevents roadbed concrete from getting dirty and makes it easy to install the track slabs at a constant height.SOLUTION: A grouting bag for slab track construction, which includes a grouting bag body 1 and a grouting port 2, is prepared. The grouting bag body 1 is made of laminated nonwoven fabric. The grouting port 2 is made of woven or knitted fabric with higher tensile strength than the laminated nonwoven fabric. The laminated nonwoven fabric is formed by laminating and bonding, on both sides of ultrafine fiber nonwoven fabric formed by accumulating thermoplastic ultrafine fibers, long fiber nonwoven fabric formed by accumulating thermoplastic long fibers with a finer diameter than the thermoplastic ultrafine fibers. The grouting bag for slab track construction is inserted between the concrete or the roadbed concrete laid on it and the track slab, or between the locking protrusions installed on the concrete slab or the roadbed concrete laid on it and the track slab. Then, the slab track is constructed by pressure-feeding and injecting filling materials from the grouting port 2.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a method for constructing a slab track for railways such as the Shinkansen, and more particularly to a method for constructing a slab track in which a filler injection bag is inserted between the roadbed concrete or the like and the track slab. [Background technology]

[0002] In railways, track construction has generally used ballast track, which uses ballast as the track bed. However, in recent years, faster trains and an increase in the number of routes have led to increased labor and costs involved in destroying the track bed and carrying out maintenance work. In response, slab track was developed with the primary goal of making the track maintenance-free, and is already in use on Shinkansen and conventional lines.

[0003] As shown in Fig. 1, a slab track is constructed by placing a track slab 13 on a roadbed concrete 12, which is poured on a concrete floor slab 11, which is the surface layer of an embankment, tunnel, bridge, etc., and laying rails 14 on the track slab 13. A horizontal layer 15 made of a filler material such as cement asphalt mortar or synthetic resin is provided between the roadbed concrete 12 and the track slab 13, so that the track slab 13 is set at a constant height. In addition, a locking projection 16 is provided on the roadbed concrete 12, and a vertical layer 17 made of a filler material is provided between the side of the locking projection 16 and the side of the track slab 13, so that the track slab 13 does not easily shift in the traveling direction of the train.

[0004] Conventionally, filler injection bags have been used to provide the horizontal layer 15 made of filler. That is, the filler is injected into the injection bag to provide the horizontal layer 15. Nonwoven fabric is used as the material for this injection bag (Patent Documents 1 and 2). However, with typical nonwoven fabric, the filler leaks, soiling the roadbed concrete 12 and making it difficult to install the track slab 13 at a constant height. In particular, the injection bag described in Patent Document 2 is characterized in that the side of the injection bag is covered with asphalt, assuming that the cement asphalt will leak (Patent Document 2, claims 1 and 2).

[0005] [Patent Document 1] Japanese Patent Application Publication No. 1-271501 [Patent Document 2] Patent No. 5329263 Summary of the Invention [Problem to be solved by the invention]

[0006] The object of the present invention is to provide a method for constructing a slab track which prevents leakage of filler such as cement asphalt mortar from an injection bag, prevents contamination of the roadbed concrete when constructing a slab track, and makes it easy to install the track slab at a constant height. [Means for solving the problem]

[0007] The present invention solves the above problem by adopting specific materials for the injection bag body and the injection port. That is, the present invention relates to a method for constructing a slab track, which includes a step of preparing an injection bag body for slab track construction, which is composed of a laminated nonwoven fabric in which a long-fiber nonwoven fabric in which thermoplastic long fibers having a finer diameter than the thermoplastic ultrafine fibers are accumulated is bonded to both sides of an ultrafine fiber nonwoven fabric in which thermoplastic ultrafine fibers are accumulated, by the adhesiveness of the thermoplastic ultrafine fibers or the thermoplastic long fibers themselves, and an injection port formed of a woven or knitted fabric having a higher tensile strength than the laminated nonwoven fabric, a step of inserting the injection bag for slab track construction between concrete or a roadbed concrete provided thereon and a track slab, and a step of pumping and injecting a filler from the injection port. The present invention also relates to a method for constructing a slab track, which includes inserting the injection bag for slab track construction between a locking protrusion installed on a concrete slab or a roadbed concrete provided thereon and a track slab, and then pumping and injecting a filler from the injection port. Effect of the Invention

[0008] The infusion bag for slab track construction used in the method for constructing a slab track according to the present invention has an infusion bag body made of a laminated nonwoven fabric, and an infusion port made of a woven or knitted fabric having a higher tensile strength than the laminated nonwoven fabric. Therefore, when the filler is pressure-fed and injected through the infusion port, the infusion port is less likely to break, and the effect of preventing the filler from leaking out is achieved. In addition, the ultrafine fiber nonwoven fabric in the laminated nonwoven fabric is made of ultrafine fibers with a small fiber diameter, so the fiber gaps are small, and the liquid components in the injected filler are less likely to leak out. The long fiber nonwoven fabric in the laminated nonwoven fabric has a large fiber diameter, so it has excellent mechanical strength and is less likely to break or burst during and after the infusion of the filler. In addition, the laminated nonwoven fabric has gaps between the fibers, so it is breathable, and air mixed in the filler can be released to the outside when the filler is injected. Therefore, by adopting the method for constructing a slab track according to the present invention, it is possible to prevent the roadbed concrete from becoming dirty and to easily install the track slab at a constant height. Furthermore, the injection bag for constructing a slab track used in the present invention is less susceptible to rainwater and other elements entering from the outside, so the filler is less likely to deteriorate, and a slab track with a long life is obtained. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic perspective view showing a conventional slab track structure. [Diagram 2] FIG. 1 is a plan view of an example of an infusion bag for constructing a slab track used in the present invention, and an infusion bag of this shape is used for constructing a flat track slab. [Diagram 3] This is another example of a plan view of an infusion bag for constructing a slab track used in the present invention, and an infusion bag of this shape is used to construct a frame-shaped track slab. [Figure 4] FIG. 4 is a plan view of an infusion bag piece used when creating the infusion bag for slab track construction shown in FIG. 2 or FIG. 3. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] The infusion bag for slab track construction used in the present invention comprises an infusion bag body 1 and an infusion port 2. The infusion bag body 1 is made of a laminated nonwoven fabric. The laminated nonwoven fabric is made by laminating and bonding a long fiber nonwoven fabric made of thermoplastic long fibers having a finer diameter than the thermoplastic ultrafine fibers on both sides of an ultrafine fiber nonwoven fabric made of accumulated thermoplastic ultrafine fibers. As the material for the thermoplastic ultrafine fibers, polyolefin resins such as polyethylene, polypropylene, or ethylene-propylene polymer, polyester resins such as polyethylene terephthalate, and polyamide resins such as nylon 6 or nylon 66 are used. The fineness of the thermoplastic ultrafine fibers is about 0.001 to 1 decitex. By accumulating such ultrafine fibers, microvoids are formed between the ultrafine fibers, and although the ultrafine fibers have air permeability, the water permeability is extremely reduced, and the injected filler is less likely to leak. The ultrafine fiber nonwoven fabric can be obtained by the so-called melt blown method, and its basis weight is 10 to 100 g / m 2 That's about it.

[0011] As for the material of the thermoplastic long fibers constituting the long fiber nonwoven fabric laminated and bonded on both sides of the ultrafine fiber nonwoven fabric, polyolefin resin, polyester resin, polyamide resin, etc. are used, as in the case of the thermoplastic ultrafine fibers. The materials of the thermoplastic ultrafine fibers and the thermoplastic long fibers are preferably the same type, for example, polyolefin resin. This is because the affinity between the ultrafine fibers and the long fibers is good when the materials are the same type, and they are easier to bond. The fineness of the thermoplastic long fibers is higher than that of the ultrafine fibers, about 1 to 30 decitex. Since the fineness of the thermoplastic long fibers is higher than that of the thermoplastic ultrafine fibers, the mechanical properties such as the tensile strength of the laminated nonwoven fabric are improved, and the infusion bag body 1 is less likely to break or burst. The basis weight of the long fiber nonwoven fabric is 5 to 100 g / m 2 The long fiber nonwoven fabric can be obtained by a conventionally known method, and is preferably obtained by the so-called spunbond method.

[0012] To laminate and join ultrafine fiber nonwoven fabrics and long fiber nonwoven fabrics, for example, the following method is adopted. That is, after obtaining a long fiber nonwoven fabric by the spunbond method, the surface of this long fiber nonwoven fabric is sprayed with thermoplastic ultrafine fibers by the meltblown method to form an ultrafine fiber nonwoven fabric. Then, thermoplastic long fibers are accumulated on the surface of the ultrafine fiber nonwoven fabric by the spunbond method to form a long fiber nonwoven fabric, thereby obtaining a laminated nonwoven fabric in which the long fiber nonwoven fabrics are laminated and joined on both sides of the ultrafine fiber nonwoven fabric. The ultrafine fiber nonwoven fabric and the long fiber nonwoven fabric are bonded to each other by the adhesiveness of the thermoplastic ultrafine fibers themselves, by spraying the thermoplastic ultrafine fibers still in a softened state onto the surface of the long fiber nonwoven fabric and accumulating the thermoplastic long fibers on the surface of the still softened ultrafine fiber nonwoven fabric. If it is desired to further advance the bonding, the laminated nonwoven fabric can be passed between a pair of heated rolls to soften the thermoplastic ultrafine fibers and / or thermoplastic long fibers, and the bonding can be performed by the adhesiveness of the thermoplastic ultrafine fibers and / or thermoplastic long fibers themselves. In this case, the thermoplastic ultrafine fibers can be sprayed in two or more stages by the meltblown method to form a two-layer or three or more layers of ultrafine fiber nonwoven fabric. Alternatively, a long-fiber nonwoven fabric can be obtained by the spunbond method, and then the thermoplastic ultrafine fibers can be sprayed on the surface of the long-fiber nonwoven fabric by the meltblown method to prepare two two-layer laminates of the ultrafine fiber nonwoven fabric and the long-fiber nonwoven fabric, which are then laminated so that the ultrafine fiber nonwoven fabrics are in contact with each other, to obtain a laminated nonwoven fabric in which the long-fiber nonwoven fabrics are laminated and bonded to both sides of the ultrafine fiber nonwoven fabric.

[0013] The basis weight of the laminated nonwoven fabric is 30 to 150 g / m 2 This laminated nonwoven fabric is excellent in water resistance, as the liquid components in the filler do not easily leak out. For example, when a water pressure of 500 mmH2O is applied for 30 minutes using a water pressure tester, the amount of water seeping out is about 50 cc or less. It is also preferable to incorporate weathering agents such as ultraviolet absorbers and light stabilizers into the thermoplastic ultrafine fibers and thermoplastic long fibers that make up the laminated nonwoven fabric. This is to prevent deterioration, as injection bags for slab track construction are often used outdoors for long periods of time.

[0014] The inlet 2 is a portion for injecting the filler and for applying pressure to pump the filler into the infusion bag body 1. Therefore, it is made of a material having higher mechanical strength, such as tensile strength, than the infusion bag body 1. For example, it is preferable to form it from a woven or knitted fabric such as nylon taffeta.

[0015] The method of producing the infusion bag for slab track construction having the shape shown in FIG. 2 can be, for example, the following method. That is, two infusion bag pieces shown in FIG. 4 are prepared. This infusion bag piece is formed by sewing an infusion bag main body piece 1a made of laminated nonwoven fabric with a thread 5 such as a sewing thread, and an infusion inlet piece 2a made of woven or knitted fabric. Of course, instead of sewing with the thread 5, it may be bonded with a hot melt adhesive or the like. In addition, 4 is a recess for fitting the locking protrusion. By overlapping two such infusion bag pieces and sewing the overlapping periphery with a thread 3 such as a sewing thread, it is possible to obtain an infusion bag for slab track construction. Of course, in this case, it is also possible to adhere with a hot melt adhesive or the like instead of sewing with the thread 3. In addition, it is also possible to produce an infusion bag for slab track construction having the shape shown in FIG. 3 by folding one infusion bag piece shown in FIG. 4 in the up-down direction and overlapping it, and sewing the overlapping periphery with a thread 3 such as a sewing thread. In this case, it is not necessary to sew or glue the folded side.

[0016] The injection bag for slab track construction shown in FIG. 2 has a body that is substantially the same shape as the flat track slab, and is used when constructing a slab track using a flat track slab. That is, the injection bag for slab track construction shown in FIG. 2 is inserted between the roadbed concrete and the flat track slab, and a filler such as cement asphalt mortar or urethane resin is injected into the injection bag body 1 from the injection port 2. Then, when the cement asphalt mortar or urethane resin hardens, a slab track structure can be constructed. Also, the injection bag for slab track construction shown in FIG. 3 is used when constructing a slab track using a frame-shaped track slab. That is, the injection bag for slab track construction shown in FIG. 3 is inserted between the left and right frame parts of the rail and the roadbed concrete, and a filler is injected into the injection bag body 1 from the injection port 2, so that a slab track structure can be constructed.

[0017] The injecting bag for slab track construction used in the present invention can also be applied between the locking protrusion and the track slab. That is, the injecting bag for slab track construction can be inserted into the vertical gap between the locking protrusion and the track slab, and the filler can be injected into the injecting bag body 1 from the injection port 2 to construct the slab track structure. Although the injecting bag for slab track construction applied to this location is not shown, for example, one having a shape as shown in Figure 3 can be wound around the side of the locking protrusion. After the slab track is constructed, the injection port 2 can be cut off or tied off. [Explanation of symbols]

[0018] 1 Infusion bag body 1a Injection bag body piece 2 Inlet 2a Inlet piece 3. Thread for sewing the overlapping edges of the infusion bag body piece and the infusion port piece 4. Recess for fitting the locking protrusion 5. Thread for sewing the infusion bag body piece and the infusion port piece 11 Concrete floor slab 12 Roadbed concrete 12 13 Track slab 14 Rail 16 engaging protrusions

Claims

1. A process of preparing an infusion bag for slab track construction, comprising: an infusion bag body made of a laminated nonwoven fabric in which a long-fiber nonwoven fabric made of thermoplastic long fibers having a finer diameter than that of the thermoplastic ultrafine fibers is bonded to both sides of the ultrafine fiber nonwoven fabric by the adhesiveness of the thermoplastic ultrafine fibers or the thermoplastic long fibers themselves; and an infusion bag for slab track construction, comprising an infusion bag body made of a laminated nonwoven fabric in which a long-fiber nonwoven fabric made of thermoplastic long fibers having a finer diameter than that of the thermoplastic ultrafine fibers is bonded to both sides of the ultrafine fiber nonwoven fabric by the adhesiveness of the thermoplastic ultrafine fibers or the thermoplastic long fibers themselves; and A step of inserting the injection bag for slab track construction between concrete or roadbed concrete provided thereon and a track slab; A step of injecting a filler through the injection port. A method for constructing a slab track, comprising:

2. The method for constructing a slab track as described in claim 1, which employs a step of inserting the injection bag for slab track construction as described in claim 1 between a locking protrusion installed on a concrete deck or the roadbed concrete installed on the concrete deck and the track slab, instead of the step of inserting the injection bag for slab track construction as described in claim 1, between a track slab and a locking protrusion installed on a concrete deck or the roadbed concrete installed on the concrete deck.

3. 3. A method for constructing a slab track according to claim 1 or 2, wherein the thermoplastic ultrafine fibers are polyolefin ultrafine fibers, and the thermoplastic long fibers are polyolefin long fibers.

4. 3. The method for constructing a slab track according to claim 1 or 2, wherein the woven or knitted fabric is nylon taffeta.

5. 3. The method for constructing a slab track according to claim 1 or 2, wherein the track slab is a flat track slab or a frame track slab.

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