JP2022163764A - Repair method for filler layer of concrete slab track - Google Patents

Abstract

To provide a repair method for a filler layer which can carry out in a short time, work to repair a wide range of the CA mortar layer serving as a filler layer between a roadbed concrete and a track concrete slab of a concrete slab track.SOLUTION: A repair method for a filler layer, which digs the filler layer located between a roadbed concrete and a track concrete slab in a concrete slab track from a side of the concrete slab track and filling a repair material therein, comprises: a first step of digging the filler layer down to a designated depth from the side of the concrete slab track; a second step of fitting sinking-prevention means onto a side face of the track concrete slab to prevent a side part of the track concrete slab from sinking; a third step of inserting a repair bag with multiple valves on its back part into a space made by the digging in the first step, positioning the valves to face a deep part of said space; a fourth step of forming a repair body by filling the repair material into the repair bag and curing it; and a fifth step of removing the sinking-prevention means fitted onto the side face of the track concrete slab during the second step.SELECTED DRAWING: Figure 2

Description

TECHNICAL FIELD The present invention relates to slab track repair technology, and more particularly to a filling layer repairing method for repairing a CA mortar layer (cement asphalt mortar) layer as a filling layer provided between roadbed concrete and a track slab.

The slab track is provided with a filling layer made of CA mortar that has a cushioning function between the roadbed concrete and the track slab made of a concrete plate laid above it. Conventionally, this CA mortar layer was made by a formwork method in which a formwork is provided and a filler is injected into the inside and hardened, and a long tube made by injecting mortar into a non-woven fabric bag. There are things.
Among these, an invention relating to a method for constructing a track slab with a CA mortar layer of the long tube type interposed is disclosed in Patent Document 1, for example.

In recent years, on slab tracks in cold, snowy regions, deterioration of the CA mortar layer has progressed due to repeated freezing and thawing caused by soaking into the CA mortar layer with water sprinkled to melt snow and rainwater. Therefore, in the slab track part where the CA mortar layer is less deteriorated, measures are taken to prevent water from penetrating into the CA mortar layer by coating the side part where the CA mortar layer is exposed with a resin. .
On the other hand, in the slab track section where the deterioration of the CA mortar has progressed considerably, the excavator was used to excavate and remove the mortar from the side of the CA mortar layer to a relatively deep part, and then the repair material was injected to restore the CA mortar layer. Repair work is underway. In the case of the CA mortar layer of the long tube method, it is also necessary to remove the non-woven fabric covering the surface, so a slab raceway repairing grinding apparatus suitable for this has also been developed.

Further, conventionally, there are inventions described in Patent Documents 2 and 3 as inventions related to a repairing device and a repairing method for a filling layer (CA mortar layer) in a slab track.
Among these, the invention of Patent Document 2 is a traveling type that is placed on the rail after excavating the filling layer between the roadbed concrete and the track slab from the side, and then providing a formwork on the outside of the track slab. A two-liquid mixing type filler is injected into the inside of the mold from the nozzle of the mixer provided in the packed bed repairing device and hardened, and then the mold is removed.

The invention of Patent Document 3 removes the deteriorated CA mortar layer from the periphery of the track slab to an appropriate depth in the horizontal direction to form a gap that opens to the outer periphery of the track slab, and the gap is filled with a repair bag from the outside. Afterwards, a repair filler is injected into the repair bag to expand the repair bag and fix it in close contact with at least the upper and lower surfaces of the gap.

Japanese Unexamined Patent Application Publication No. 2010-203178 JP 2015-224418 A JP 2012-180634 A

However, in the case of the filling layer repair method described in Patent Document 2, since it is necessary to install and remove the formwork on the roadbed concrete, there are many work processes, and the problem is that it takes a considerable amount of time and money. There is
On the other hand, in the case of the filling layer repair method of Patent Document 3, although there is an advantage that the work of installing and removing the formwork is unnecessary, a plurality of It is necessary to repeat the operation of inserting the repair bag and sequentially injecting the filler into the repair bag.

In addition, in the filling layer repair method of Patent Document 3, in order to fill the gap remaining at the back of the gap where the repair bag is inserted, the track slab is provided with an injection hole in the vertical direction in advance, and the filler is injected. However, there is still a problem that it takes a lot of time and the cost is not sufficiently reduced.
Moreover, if the CA mortar layer is excavated over a wide area, both sides of the track slab may sink before the filler hardens. There is a problem that it is not suitable for large-scale repair.

The present invention was made under the above background, and repairs a CA mortar layer as a filling layer between the roadbed concrete of the slab track and the track slab over a wide area in a short time and at a low cost. It is an object of the present invention to provide a method for repairing a packed layer in a slab track.

In order to achieve the above object, the present invention
A method for repairing a filling layer in a slab track, wherein the filling layer provided between the roadbed concrete and the track slab in the slab track is excavated from the side of the slab track and filled with a repair material,
A first step of excavating the filled layer from the side of the slab track to a predetermined depth;
a second step of attaching a sinking prevention means for preventing sinking of the side portion of the track slab to the side surface of the track slab;
A repair bag having a size corresponding to the space and having a plurality of valves on its back is inserted into the space excavated in the first step so that the valves face the inner part of the space. a third step;
a fourth step of filling the repair bag with a repair material and curing the repair material to form a repair body;
and a fifth step of removing the anti-sinking means attached to the side surface of the track slab in the second step.

According to the method according to the above procedure, after attaching the subduction prevention means to the side surface of the track slab, the repair bag is inserted into the excavation space, filled with the repair material, and hardened to form a repair body (long tube). Since it is possible to fill the repair material while preventing the side of the track slab from sinking, it is possible to extensively repair the filling layer (CA mortar layer) between the roadbed concrete and the track slab. can. In addition, since it is necessary to install and remove the formwork on the roadbed concrete, the work time and cost can be reduced. Furthermore, since the repair work can be completed in a short period of time, it is possible to carry out the repair work during night hours when commercial trains do not run.

Here, desirably, in the fourth step, the repair material is injected from the front side of the repair bag and the center in the longitudinal direction.
According to this method, since the repair material injected from the front side of the repair bag and the center in the longitudinal direction moves in the front-rear direction and flows out to the inner part of the excavated space, the repair material flows out to the inner part of the excavated space. It is possible to prevent the slab structure from becoming weak due to cavities without repair material.

In addition, preferably, the repair bag is formed so as to have a length larger than the length in the longitudinal direction (front-rear direction) of the track slab when filled with the repair material.
According to this method, since the length of the repair bag is longer than the length of the track slab, the repair material injected into the repair bag flows into the inner part of the excavated space and flows back and forth along the wall of the inner part. When it reaches the boundary of the adjacent track slab, the edge of the repair bag touches the edge of the adjacent repair bag and acts as a barrier, preventing the repair material from leaking out to the outside of the track slab. can be prevented.

Preferably, the anti-sinking means comprises fasteners fixed to the side surfaces of the track slab by a pair of fixing bolts, and vertical holding bolts screwed into the fasteners. I made it so that
According to this method, a simple and proven anti-sinking means is attached to the track slab to prevent both sides of the track slab from sinking until the repair material hardens, and the upper surface of the track slab is repaired. You can avoid being lower than before.

Further, desirably, the pair of fixing bolts are provided in advance on the side surface of the track slab by using a pair of bolt holes in which bolts for fixing a jig for suspension are fixed. Fasteners are secured to the sides of the track slab.
According to this method, when repairing the mortar layer as a filling layer of a slab track having a flat plate slab, the repair can be performed without processing the flat plate slab at all. A decrease in strength can be prevented.

According to the method for repairing the filling layer in the slab track according to the present invention, the CA mortar layer as the filling layer between the roadbed concrete of the slab track and the track slab can be repaired over a wide area for a short time without adversely affecting the track slab. It can be repaired easily and at low cost.

1 is a perspective view showing a structure of a slab track to which a method for repairing a CA mortar layer as a filling layer according to the present invention is applied; FIG. 1 is a perspective explanatory view showing an example of a structure of a slab track by large-scale repair to which the present invention is applied; FIG. (A) is a perspective view showing the state of the inner surface of a long tube inserted into the excavation space of the CA mortar layer, and (B) and (C) are perspective views showing specific examples of valves provided on the inner surface of the long tube, respectively. It is a diagram. (A) is a perspective view showing a specific example of means for supporting the weight of the track slab after the repair material is injected into the long tube, and (B) is an explanatory view showing another specific example of means for supporting the weight of the track slab. be. (A) is a perspective view showing how to lift the flat plate slab when constructing the first slab track, and (B) is an enlarged view showing the state after the side fasteners of the flat plate slab have been removed.

Hereinafter, an embodiment of a method for repairing a CA mortar layer as a filling layer in a slab track according to the present invention will be described in detail with reference to the drawings.
FIG. 1 shows the structure of a slab track to which the filling layer repair method according to the present invention is applied. As shown in FIG. 1, the slab track consists of roadbed concrete 11 of a predetermined thickness provided on a concrete floor slab (not shown) along the direction in which the track extends, and CA mortar on the roadbed concrete 11 . It has a structure in which a track slab 13 (length 4.95 m, width 2.34 m, thickness 16 cm) is laid through layers 12 . The width of the CA mortar layer 12 is the same as the width of the track slab 13 .

The track slab 13 is constructed by arranging a plurality of rectangular concrete plates in the rail extension direction when viewed from above. It is fastened to the track slab 13 .
More specifically, cylindrical locking projections 14 are provided at predetermined intervals in the center of the roadbed concrete 11 , and at the center of the front end and the center of the rear end of each rectangular concrete plate that constitutes the track slab 13 . A semi-cylindrical notch having a diameter slightly larger than that of the locking projection 14 is formed. configured to be positioned. A gap is filled between the outer periphery of the locking projection 14 and the track slab 13 by injecting and hardening a filler 15 .

As the CA mortar layer 12, there are those made by a formwork method and those made by a long tube in which CA mortar is injected into a bag made of non-woven fabric. The long tube type CA mortar layer 12 is formed by installing a long tube bag in the gap between the roadbed concrete 11 and the track slab 13, and filling the entire tube with a cement-asphalt mixture from an injection port provided on one side of the bag. It is constructed by pouring and cutting off the ends of the inlets that protrude laterally from the track slab 13 after curing. Bags for long tubes are made of, for example, long-fiber nonwoven fabric made of polyester, polyethylene terephthalate, or the like.

The cement-asphalt mixture injected into the long tube bag contains, for example, cement/asphalt/fine aggregate in a predetermined ratio. The asphalt component is added as an asphalt emulsion, and when the water is removed and the asphalt solidifies, it exhibits toughness as an elastic body. In addition, in order to improve the weather resistance of the long tube, the side surface of the long tube may be treated with light resistance.

Here, as the light resistance treatment, there are a method of improving the light resistance of the fibers constituting the nonwoven fabric, a method of coating the surface including the side surface of the long tube with a light resistant resin, and a method of completely covering the side surface of the long tube with asphalt. .
Among these, as a method for improving the light resistance of constituent fibers of a nonwoven fabric, there is a method of mixing constituent fibers with a light stabilizer to form fibers. On the other hand, as a method of coating the surface including the side surface of the long tube with a light-resistant resin, for example, after injecting a cement-asphalt mixture into the long tube, there is a method of applying an acrylic light-resistant paint etc. to the exposed side surface of the long tube. .

When the CA mortar layer 12 having the above structure is deteriorated, as described above, partial repair or large-scale repair (large cross-section chipping repair) is performed according to the degree of deterioration. Among these, the present invention is intended for large-scale repair. In the large-scale repair in the embodiment, the CA mortar layer 12 below the track slab 13 with a width of about 2.5 m is excavated from both sides to about 70 cm deep to form a new filling layer. done. The excavation depth of the CA mortar layer 12 is not limited to around 70 cm.

The structure and method of slab track for large-scale repairs are described in detail below.
FIG. 2 shows an example of the structure of a slab track after large-scale repair to which the present invention is applied. As shown in FIG. 2, the repair of the slab track in this embodiment is performed by excavating both sides of the CA mortar layer 12 below the track slab 13 along the rail extending direction, and Long tubes 16A and 16B, which are strip-shaped when viewed from above and filled with a repair material, are interposed.

Although FIG. 2 shows the track slab 13 separated from the CA mortar layer 12, in the actual construction, the track slab 13 is not lifted, and both sides of the CA mortar layer 12 are lifted. Spaces for inserting the long tubes 16A and 16B are formed by excavating them respectively. After excavating both sides of the CA mortar layer 12, the long tubes 16A and 16B are formed by inserting a repair bag forming the long tubes into the excavation space, and then inserting uncured CA mortar or the like into the bag. Since the long tubes 16A and 16B can be easily handled manually by injecting and hardening the material, there is no need to bring large machinery or heavy machinery into the track.

As described above, in the case of the method of excavating the CA mortar layer 12, inserting a repair bag therein, and injecting the repair material to form the long tubes 16A and 16B, if the CA mortar layer is excavated over a wide range, the track If both sides of the slab 13 sink under their own weight and the repair material hardens in that state, there is a risk that the upper surface of the track slab 13 will become lower than before repair. Therefore, in this embodiment, in order to avoid such a risk, a means for supporting the weight of the track slab 13 is temporarily installed until the repair material is completely hardened.

In addition, the CA mortar layer formed first corresponds to the track slab 13 adjacent in the front-rear direction for both the slab track of the flat plate slab that does not use the long tubes and the slab track of the formwork slab that uses the long tubes. Although there was a gap between the mortar layers, in this embodiment, the long tubes 16A and 16B that are longer in the front-rear direction than the conventional long tubes are used, and the injection of the repair material is completed. In this case, the long tubes adjacent to each other in the front-rear direction (rail extending direction) are in contact with each other.

As shown in FIG. 3A, the long tube 16A (also 16B) to be used has a plurality of valves 16b at predetermined intervals on the side facing the deep part of the excavation space, that is, on the back surface. set aside. In addition, a cement asphalt injection port 16c is provided at the center of the front side of the long tube 16A in the front-rear direction. As a result, the repair material injected from the center of the repair bag moves in the front-rear direction and flows out to the back of the excavation space through the valve 16b on the back surface. can be prevented from occurring and weakening the slab structure.

FIG. 3B shows a specific configuration example of the valve 16b.
The valve 16b shown in FIG. 3B is provided inside each opening hole 16a formed in the back (inner side) of the long tube 16A, and the repair material of the long tube 16A can flow out to the outside. A check valve is used which has a structure in which the outflowing repair material is difficult to return.

FIG. 3C shows another configuration example of the valve 16b.
The valve 16b shown in FIG. 3(C) is slightly larger than the opening hole 16a so as to cover the opening hole 16a with a diameter of several mm to several cm formed in the back (inner surface) of the long tube 16A. A cross-shaped cut is provided in the center of a disk-shaped elastic body having a diameter. The material of the valve 16b may be any material, such as polyethylene terephthalate, which is the material of PET bottles, as long as it is elastically deformable and strong. Note that the configuration of the valve 16b is an example, and is not limited to the configuration described above.

When a long tube as described above is used, after excavating the side of the CA mortar layer 12 and inserting a repair bag forming the long tube into the excavated space, cement asphalt is injected from the injection port 16c. Then, the long tube is filled with cement asphalt, and the cement asphalt flows out from the valve 16b provided on the back side to fill the gap between the deep part of the excavation space and the long tube. In addition, when the gap in the inner part is filled, the cement asphalt moves to the outer side and fills the gap between the upper and lower walls of the excavation space and the long tube.

As a result, it is possible to prevent rainwater from entering the gaps between the excavated space of the CA mortar layer 12 and the long tubes 16A and 16B, which would otherwise accelerate deterioration. In addition, since the length of the long tubes is long and the adjacent long tubes are in contact with each other, the cement asphalt that has flowed into the deep part of the excavation space is prevented from leaking out from the gap between the front and back long tubes. can be prevented.
Furthermore, the repair material injection port 16c of the long tube is provided not at the end of the tube but at the central portion in the front-rear direction (longitudinal direction) of the outer surface of the tube. As a result, the injected repair material spreads forward and backward from the central portion of the tube, so that no cavities remain in the deep portion of the excavated space of the packed bed.

For the repair bag, a long fiber nonwoven fabric or the like similar to the long tube used when providing the filling layer when constructing the slab track for the first time may be used. Since the repair bag made of long-fiber nonwoven fabric has the property that the injected cement asphalt oozes out from the surface, the repair bag inserted into the space created by excavating the CA mortar layer 12 is also used in this embodiment. When the bag is filled with cement asphalt, it oozes out from the surface and fills the gaps between the track slab 13 above and the roadbed concrete 11 below.

FIG. 4 shows a specific example of the anti-sinking means for supporting the weight of the track slab 13 after the repair material is injected into the repair bag as described above. Among these, FIG. 4A shows a plurality of L-shaped fasteners 22 fixed to the outer surface of the track slab 13 by a pair of fixing bolts 23, and a female screw formed in the horizontal piece 22a of the fastener 22. A holding bolt 24 is turned and screwed until the tip comes into contact with the surface of the roadbed concrete 11 .

When the track slab 13 is a flat plate slab, a pair of jigs 25 for suspension are attached to the outer surface of the track slab 13 as shown in FIG. are fixed by means of fixing bolts 23 of . Therefore, after the track slab 13 is installed, the fixing bolts 23 and jigs 25 are removed, and the bolt insertion holes on the outer surface of the track slab 13 are closed with caps 26 as shown in FIG. 5(B). 4(A) can be attached with a fixing bolt 23 using the bolt insertion hole.

The holding bolts 24 prevent the upper surface of the track slab 13 from sinking by supporting the weight of the track slab 13 until the repair material in the long tube hardens, and are removed after the repair material hardens. . Since the repair material is selected to have a property that can be cured in a short time, the fastener 22, the fixing bolt 23, and the holding bolt 24 are usually removed before the first train passes and after confirmation of curing. .

FIG. 4(B) shows the weight of the track slab 13 when it did not harden before the first train passed or when trouble occurred during the work and the filling of the repair material could not be completed within the scheduled time. A specific example of a temporary support means for supporting the
The temporary support means shown in FIG. 4B is such that a plurality of metal plates 27 are inserted in an overlapping state between the track slab 13 and the roadbed concrete 11 in the excavation space. By inserting a plurality of metal plates 27, it is easy to adjust the height of the excavation space even if the height of the excavation space varies. Although the metal plate 27 may have the same thickness, it is desirable to prepare different thicknesses.

As described above, in the repair method of the present embodiment, the retention bolts 24 and the metal plates 27 prevent the track slab 13 from sinking until the cement asphalt or other repair material filled in the long tube hardens. can. Therefore, even if the CA mortar layer 12 under the track slab 13 is excavated relatively deeply from the side, both sides of the track slab 13 can be prevented from sinking, and the CA mortar layer 12 can be repaired over a wide area. In addition, since the repair work of the CA mortar layer 12 can be completed in a short period of time, it is possible to carry out the repair work during night hours when trains in service are not running.
It should be noted that the installation of the anti-sinking means consisting of the fasteners 22 and the retaining bolts 24 on the side surface of the track slab 13 is preferably performed before the excavation of the CA mortar layer 12. may be performed during the progress of

Although the invention made by the inventor has been specifically described based on the embodiment, the invention is not limited to the embodiment. For example, in the above-described embodiment, cement asphalt is used as a repair material to be filled in the long tubes 16A and 16B as repair bodies, but any material having a strength equal to or greater than that of cement asphalt when hardened can be used. , You may make it fill with materials other than a cement asphalt.
In the above-described embodiment, the long tubes 16A and 16B as the repair bodies are provided with the injection port 16c for the repair material. You may make it inject|pour a repair material.

11 roadbed concrete 12 CA mortar layer (filling layer)
13 track slab 14 locking projection 16A, 16B long tube (repair body)
16a opening hole 16b valve 16c repair material inlet 20 rail 21 rail fastener 22 fastener 23 fixing bolt 24 holding bolt 25 hanging jig 26 cap 27 metal plate

Claims (5)

A method for repairing a filling layer in a slab track, wherein the filling layer provided between the roadbed concrete and the track slab in the slab track is excavated from the side of the slab track and filled with a repair material,
A first step of excavating the filled layer from the side of the slab track to a predetermined depth;
a second step of attaching a sinking prevention means for preventing sinking of the side portion of the track slab to the side surface of the track slab;
A repair bag having a size corresponding to the space and having a plurality of valves on its back is inserted into the space excavated in the first step so that the valves face the inner part of the space. a third step;
a fourth step of filling the repair bag with a repair material and curing the repair material to form a repair body;
a fifth step of removing the anti-sinking means attached to the side surface of the track slab in the second step;
A method for repairing a packed bed in a slab track, comprising: 2. The method of repairing a filling layer in a slab track according to claim 1, wherein in the fourth step, the repair material is injected from the front side of the repair bag and the center in the longitudinal direction. 3. The repair bag according to claim 1, wherein the repair bag filled with the repair material has a length greater than the longitudinal length of the track slab. A method for repairing a packed layer in a slab track. The anti-sinking means is composed of a fastener fixed to the side surface of the track slab by a pair of fixing bolts, and a vertical holding bolt screwed into the fastener. A method for repairing a filling layer in a slab track according to any one of claims 1 to 3. The pair of fixing bolts are provided in advance on the side surface of the track slab, and the fasteners are attached to the track using a pair of bolt holes in which bolts for fixing jigs for hanging are fixed. 5. A method of repairing a packed layer in a slab track according to claim 4, wherein the filling layer is fixed to the side of the slab.

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