JP5167193B2 - Repair method for underground structures and waterstop structures - Google Patents

Description

  The present invention relates to an underground structure and a repair method for a water stop structure.

  An underground structure constructed by connecting two or more frames (for example, box culverts, segment rings, propulsion pipes, etc.) connected to each other and having a water stop structure at the joint between the frames is known. (See Patent Document 1).

  This water stop structure has sufficient flexibility (followability), but if an unexpected ground deformation occurs in the surrounding ground of an underground structure due to an earthquake or ground subsidence, it will be more than expected between the frames. Opening amount and deviation may occur, and the water stop function may be impaired. When repairing the water-stopping structure to restore the water-stopping function, it is necessary to remove the water-stopping plates, etc. that were provided between the enclosures. Since there is concern about the inflow of groundwater and earth and sand, it is necessary to improve the ground around the still water structure from the ground or from the shaft.

JP 2006-90100 A

  However, for example, if the underground structure is built at a deep depth or if the work site cannot be secured on the ground, it will be difficult to improve the ground from the ground, leading to prolonged repair work and the cost of repair. It will increase. In addition, there is a case where the ground improvement cannot be performed on a portion that is hidden behind the underground structure (for example, the ground below the underground structure).

  From such a point of view, the present invention is an underground structure in which a plurality of enclosures are connected in series, and an underground structure capable of easily and quickly repairing a water stop structure provided between the enclosures. It is an object to provide a repair method for a water stop structure that can easily and quickly repair a water stop structure of an underground structure formed by connecting a plurality of frames. To do.

  An underground structure according to the present invention that solves such a problem is an underground structure formed by connecting a plurality of frames, and a water stop structure that stops the joint between the adjacent frames. And a freezing pipe embedded in at least one of the housings, and the freezing pipe is provided so as to pass through the ground side of the water stop structure.

  According to the present invention, it is possible to freeze the surrounding ground of the water-stopping structure simply by passing the cooling liquid through the freezing pipe embedded in the housing. That is, according to the present invention, it becomes possible to easily and quickly take measures against the surrounding ground of the water stop structure to be repaired, so that repair (including replacement and reconstruction) of the water stop structure can be easily and quickly performed. Can be performed. Further, according to the present invention, since the freezing pipe is piped so as to pass through the ground side rather than the water stopping structure, the freezing pipe does not get in the way when repairing the water stopping structure, and even during repair work Since the cooling liquid can be passed through the freezing pipe, it is possible to perform repair work while maintaining the frozen state of the surrounding ground in a good state.

  For example, the inlet and the outlet that communicate with the freezing tube may be provided on the inner surface of the casing. In this way, it is possible to connect the cooling liquid transport pipe for circulating the cooling liquid to the inlet and the outlet only by the work from the inner space side of the housing, so that the freezing work can be started quickly and easily. It becomes possible.

  Further, a coolant transport pipe extending from the freezing pipe to the ground may be provided outside the housing. If it does in this way, when performing repair work in the inner space side of a frame, since a cooling fluid transport pipe does not get in the way, repair work becomes easy.

  It is preferable to provide a repair target area to be cut when repairing the water stop structure in the casing, and embed the frozen pipe outside the repair target area. If it does in this way, since it becomes possible to leave a freezing pipe after repair work, it becomes possible to reuse a freezing pipe when repairing the same location again.

  The repair method of the still water structure according to the present invention that solves the above-described problem is provided at the joint between the enclosures using a freezing pipe embedded in an underground structure in which a plurality of enclosures are connected in series. A method for repairing a water stop structure, in which a coolant is passed through the freezing pipe that has been piped so as to pass through the ground side of the water stop structure, and the ground around the water stop structure is frozen. Then, while leaving the freezing pipe, the water stop structure is removed from the inner air side of the housing, and a new water stop structure is constructed.

  According to the present invention, it is possible to repair the water stop structure only by work from the inner space side of the housing. In addition, according to the present invention, since the freezing pipe is piped so as to pass the ground side rather than the water stopping structure, the freezing pipe does not become an obstacle when removing the water stopping structure. Since the cooling liquid can be allowed to flow through the freezing pipe even in the removed state, the repair work can be performed while maintaining the frozen state of the surrounding ground in good condition. Further, according to the present invention, since the frozen tube is left after the repair work, the frozen tube can be used again when repairing the same portion again.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to repair the water stop structure provided between the housings simply and quickly.

It is a perspective view which shows the underground structure based on suitable embodiment of this invention. It is a fragmentary longitudinal cross-sectional view of the underground structure shown in FIG. It is a schematic cross-sectional view of the underground structure shown in FIG. (A)-(c) is a longitudinal cross-sectional view which shows the repair method of the still water structure using the underground structure of FIG. (A) And (b) is a longitudinal cross-sectional view which shows the modification of an underground structure. It is a cross-sectional view showing another modification of the underground structure.

  DESCRIPTION OF EMBODIMENTS Preferred embodiments of the present invention will be described in detail with reference to the drawings. In the following description, the same reference numerals are used for the same elements, and duplicate descriptions are omitted.

  In the present embodiment, as shown in FIG. 1, an underground structure 1 configured by connecting a plurality of box culverts (frames) 10, and a water stop structure 20 provided in the underground structure 1. The repair method of the water stop structure which repairs (refer FIG. 2) is demonstrated.

  As shown in FIG. 2, the underground structure 1 includes a plurality of box culverts 10 connected to the ground, and a water stop structure 20 that stops a joint between adjacent box culverts 10 and each box. And a freezing tube 30 embedded in an end portion of the culvert 10.

The box culvert 10 is a concrete member having a rectangular cross section, and is continuously provided in the ground by a propulsion method, a shield method, an open-cut method, or the like.
In the present embodiment, the box culvert 10 is used as the casing, but the configuration of the casing is not limited, and may be another casing such as a segment ring or a propulsion pipe.

A cutout portion 11 for installing a secondary waterstop plate 22 of the waterstop structure 20 is formed on the end surface of the box culvert 10 in the axial direction.
In addition, the notch part 11 is formed as needed and may be omitted.

  The water stop structure 20 prevents intrusion of groundwater or earth and sand from the joint between the box culverts 10, and in this embodiment, as shown in FIG. A water plate (seismic joint, etc.) 22 is provided.

  The primary water blocking plate 21 is a resin plate material and is disposed approximately in the middle of the box culvert 10 in the thickness direction. The primary water blocking plate 21 is disposed across both the box culverts 10 and 10, thereby closing the joint.

  The primary water blocking plate 21 includes a tubular portion 21a and embedded portions 21b and 21b extending forward and backward from the tubular portion 21a.

  The tubular portion 21a is disposed between the box culverts 10. The tubular portion 21a is configured to follow a predetermined amount by extending and deforming when a gap or an opening occurs in the joint between the box culverts 10 and 10. Further, the tubular portion 21a is torn when a deviation or opening of a predetermined amount or more occurs.

In the primary water blocking plate 21, one embedded portion 21 b is embedded in one box culvert 10 and the other embedded portion 21 b is embedded in the other box culvert 10, thereby closing the joint.
In addition, the structure of the primary water stop board 21, a fixing method, etc. are not limited.

  The secondary water blocking plate 22 is a plate material disposed inside the primary water blocking plate 21, and is disposed across the two box culverts 10, 10 at a joint between adjacent box culverts 10. The joint is closed.

  The secondary water blocking plate 22 has one end fixed to the notch 11 of the one box culvert 10 and the other end fixed to the notch 11 of the other box culvert 10 via a bolt 23.

  The secondary water stop plate 22 is a rubber-made plate material, and is configured to expand and contract with respect to the displacement and separation between the box culverts 10. In addition, the material and structure of the secondary water stop plate 22 are not limited.

  The freezing pipe 30 is a pipe material for freezing the surrounding ground by circulating a coolant, and as shown in FIGS. 2 and 3, the box culvert passes through the ground side rather than the water stop structure 20. 10 is embedded in the end portion of the box culvert 10 along the outer peripheral surface.

  In this embodiment, a stainless steel pipe is used as the freezing pipe 30 to prevent oxidation by the coolant. Therefore, the freezing tube 30 can be used repeatedly. In addition, the material and structure of the freezing tube 30 are not limited.

  The inlet 31 and the outlet 32 leading to the freezing tube 30 are provided on the inner surface of the box culvert 10, and the inlet 31 connecting the inlet 31 and the outlet 32 and the freezing tube 30 are connected to the end of the box culvert 10. 33 and a discharge pipe 34 are embedded.

The freezing pipe 30, the injection pipe 33, and the discharge pipe 34 are embedded outside the repair target region 12 that is cut when the water stop structure 20 is repaired.
Moreover, the freezing pipe 30 is embedded in the ground G side in the cross section of the box culvert 10 and at a position effective for freezing of groundwater and earth and sand (ground G) around the joint between the box culverts 10.

  When the freezing tube 30 is not used, plugs are respectively installed at the inlet 31 and the outlet 32.

Next, the repair method of the water stop structure concerning this embodiment is demonstrated.
As shown in FIG. 4A, when a large force acts on the underground structure 1 due to an earthquake or the like, the box culvert 10 moves, and the allowable value of the water blocking structure 20 at the joint between the box culverts 10 ( The case where the damaged water-stopping structure 20 is repaired when the above displacement occurs is described.

First, the cooling liquid is passed through the freezing pipe 30 to freeze the ground G around the joint between the box culverts 10 to form the frozen portion G1.
At this time, by curing (covering) the inner surface of the box culvert 10 with a heat insulating material or the like, the surface of the box culvert 10 is prevented from being exposed to warm air inside the box culvert 10. This prevents condensation from occurring due to a temperature difference between the ground G side and the inside of the mine (inside sky), and prevents the cooled concrete from being warmed by the warm air in the mine. In addition, it is possible to use a well-known material suitably for a heat insulating material.

  The coolant is flowed by connecting a coolant transport pipe 35 to the inlet 31 and the outlet 32 and circulating the coolant to the freezing pipe 30 via the coolant transport device 36. In this embodiment, brine (saturated aqueous solution of sodium chloride) is used as the coolant, but the coolant is not limited. The coolant transport pipe 35 is piped to the ground part, and may transport the coolant from the ground part, or may be configured to circulate in the mine.

  By forming the frozen part G1, inflow of groundwater, earth and sand, etc. from the joint between the box culverts 10 is prevented.

Next, as shown in FIG. 4B, a hole is drilled from the inner side of the box culvert 10 with the freezing tube 30, the injection tube 33, and the discharge tube 34 left, and the water stop structure 20 is removed. .
At this time, the cooling liquid is continuously passed through the freezing pipe 30 and the water stoppage by the freezing part G1 is maintained.

If the water stop structure 20 is removed, as shown in FIG.4 (c), the primary water stop plate 21 and the secondary water stop plate 22 will be arrange | positioned, and new water stop structure 20 'will be constructed | assembled.
And the repair of a water stop structure is completed by defrosting frozen part G1.
At this time, the primary water stop plate 21 may be left in a damaged state, and only the secondary water stop plate (seismic joint or the like) 22 may be replaced to construct a new water stop structure 20 ′.

  In addition, when the waterstop structure 20 is repaired, the sand packed in the belt-like bag is backfilled around the joint between the box culverts 10 to prevent liquefaction around the joint and to repeatedly freeze and thaw. It is good also as a possible structure. Here, the sand is not necessarily packed in a bag. Further, the material to be backfilled around the seam is not limited to sand, and other materials effective for repeated freezing may be used. In this case, the material to be used may or may not be packed in a belt-like bag like the sand. Moreover, you may take a countermeasure against liquefaction separately.

  As described above, according to the underground structure according to the present embodiment, the surrounding ground is simply and quickly frozen by simply passing the cooling liquid through the freezing pipe 30 and the water is stopped. Can be repaired.

  Further, since the freezing tube 30 is embedded in the cross section of the box culvert 10, protection of the freezing tube 30 becomes unnecessary. Moreover, since the freezing pipe 30 etc. are arrange | positioned in the construction range of the box culvert 10, it does not require an additional construction separately and is economical.

Further, by disposing the freeze tube 30 in the vicinity of the water stop structure 20, the water stop at the time of repair is excellent.
Since repair is performed from the inner space side of the box culvert 10, repair work can be easily performed even for underground structures arranged at deep locations.

Since the repair is performed while the frozen pipe 30 is maintained, even if the water stop structure 20 is damaged again, the water stop structure 20 can be repaired using the freeze pipe 30 repeatedly.
Moreover, in order to perform water stop by freezing without injecting a water stop material or the like into the ground G, if the frozen part G1 is thawed, the original state is restored. Therefore, repair can be performed without affecting the natural system.

As mentioned above, although preferred embodiment was described about this invention, this invention is not restricted to said each embodiment, In the range which does not deviate from the meaning of this invention, it can change suitably.
For example, in the above embodiment, the freeze tubes 30 are arranged in a single row, but as shown in FIG. 5A, a plurality of freeze tubes 30 (two rows in the drawing) may be arranged. Thereby, the range of freezing part G1 can be widened and the water stop effect can be improved more.

  In the above embodiment, the coolant transport pipe is disposed in the inner space of the box culvert. However, as shown in FIG. 5B, the coolant transport pipe 35 is piped outside the box culvert 10. Also good. As a result, when the repair work is performed on the inner space side of the housing, the coolant transport pipe does not get in the way, so that the repair work is facilitated.

  In the above embodiment, the cryopipe is arranged along the outer peripheral surface of the box culvert in the cross section of the integrally formed box culvert. However, a plurality of box culverts 10 'shown in FIG. If the constituent members 13, 13, and 13 are combined, the freezing pipe 30 may be provided for each constituent member 13. In addition, the code | symbol 14 in FIG. 6 is invert concrete.

  Moreover, in the said embodiment, although the freezing pipe | tube 30 shall be piping outside the repair object area | region 12, when the freezing pipe 30 does not need to be used repeatedly, the installation location of the freezing pipe 30 is the circumference | surroundings of a joint. As long as the ground G can be frozen, it is not limited to the outside of the repair target region 12.

  Although the case where the primary water stop board 21 and the secondary water stop board 22 were provided as the water stop structure 20 was demonstrated, the structure of the water stop structure 20 is not limited to this.

1 Underground structure 10 Box culvert
12 Repair target area 20 Water stop structure 30 Freezing pipe 31 Inlet 32 Outlet 35 Coolant transport pipe G Ground G1 Freezing part

Claims (5)

An underground structure formed by connecting a plurality of frames,
A water stop structure that stops the joint between the adjacent bodies;
A freezing tube embedded in at least one of the housings,
The underground structure is characterized in that the freezing pipe is piped so as to pass through the ground side rather than the water stop structure.   The underground structure according to claim 1, wherein an inlet and an outlet that communicate with the freezing pipe are provided on an inner surface of the housing.   The underground structure according to claim 1, wherein a coolant transport pipe extending from the freezing pipe to the ground is provided outside the housing. In the case, a repair target area to be cut when repairing the water stop structure is set,
The underground structure according to any one of claims 1 to 3, wherein the freezing pipe is embedded outside the repair target region. A method of repairing a water stop structure provided at a joint between the enclosures using a freezing pipe embedded in an underground structure formed by connecting a plurality of enclosures,
Flowing the coolant through the freezing pipe that has been piped to pass through the ground side rather than the water stop structure, after freezing the ground around the water stop structure, with the freezing pipe left, A repair method for a water stop structure, wherein the water stop structure is removed from an inner air side of the housing and a new water stop structure is constructed.

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