JP2000110497A - Water stop construction method for concrete underground structure jointly using freezing method, and water stop device used therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stop water using a freezing method in combination to stop water in the case of an underground structure being flooded. SOLUTION: As a primary treatment, a large number of a freezing mixture filling holes are drilled around a water springing-out large bore opening part of a concrete wall, at specified spaces so as to pierce the concrete wall, and a freezing mixture is filled from the filling holes to freeze spring water or discharge water discharged from the opening part. As secondary treatment, after the spring water or discharge water from the opening part is frozen, water stop material filling holes are drilled anew between the freezing mixture filling holes so as to pierce the concrete wall, and within the time before thawing of the frozen part, water stop material is filled from the water stop material filling holes to harden a water flowing part at the back face of the wall. A recess formed by thawing of the frozen part of spring water or discharge water from the opening part is filled with concrete or the like, and a concrete internal wall surface is finished to complete water stop work. An adjustable filling pipe or packer pipe with a diameter enlargeable part in correspondence with the change of bores of the filling holes is used to fill the water stop material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water stopping method using a freezing method in order to stop a large amount of water from flowing into an underground structure, and a water stopping device used for the method.

[0002]

2. Description of the Related Art Conventionally, in a concrete underground structure such as a tunnel, an underground tunnel, and a basement, groundwater outside the structure passes through a crack in a concrete wall, a defect in concrete work, a joint of a concrete structure, and the like. There is a problem that water often leaks into the underground room or underground room, so that there is a problem in that the civil engineering work is hindered, and there is a problem in the water discharge treatment after the completion of the structure.

[0003]

As a countermeasure against such flooding, the present inventor has invented a method of stopping water for a concrete underground structure as disclosed in the specifications of Japanese Patent Nos. 1833264 and 2777249. And implemented it. In summarizing these inventions, after the water from the jet port spouting through the through-hole opening on the inner surface of the wall is temporarily fixed by closing the jet port, the cement mixture is applied at a pressure of ³ to 5 kg / cm ² . Inject into the through hole from the spout and press the cement mixture against the outside wall of the water leaking part by the pressure of groundwater outside the wall, and stop the water by forming a cement solidified layer that spreads on the outside wall of the wall It is characterized by. Such a water stoppage method is effective for spring water of about 200 liters / minute. However, when the spring water is larger than that, it is spouting from a large-diameter opening of 100 mm or more. In this case, it becomes difficult to inject the cement mixture from the opening against the pressure of the discharge water.

[0004]

SUMMARY OF THE INVENTION Accordingly, the present inventor has found the case of such a large-scale concrete wall spring. The freezing method conventionally used for strengthening the ground and impermeable water is applied to the waterproofing of concrete walls, and the large-scale spring water as described above is temporarily frozen while cement is mixed through another injection hole. The liquid is injected into the outer surface of the wall of the water leaking section to perform the above-described water stoppage. That is, as a primary treatment, a large number of frozen material injection holes are drilled at predetermined intervals around the large-diameter opening where the concrete wall is springing so as to penetrate the concrete wall, and frozen from the injection hole. The material is injected to freeze the spring water or discharge water discharged from the opening.

[0005] Next, as a secondary treatment, after the spring water or discharge water from the opening is frozen, a new water-stopping material injection hole is inserted between the frozen material injection holes so as to penetrate the concrete wall. During the time until the hole is cut and the frozen portion is thawed, a water-stopping material is injected from the water-stopping material injection hole, and the flowing water portion on the back surface of the wall is hardened. As a result, even if the frozen portion of the spring water or the discharge water from the opening is thawed, the back surface of the opening is closed by the hardening of the waterproof material, and the spring water or the discharge water disappears. Thereafter, the depression where the frozen part of the spring water or the discharge water from the opening is melted is filled with concrete or the like to finish the inner wall surface of the concrete, and the waterproofing work is completed.

[0006] The injection of the waterproof material is performed as follows. That is, as a first step, only cement is mixed with water at a pressure of ^{3 to 5} kg / cm ² into the frozen soil outside the concrete wall or in the water through the through hole at a cement mixing ratio slightly higher than that of the water. The mixed cement mixture is injected to block the fine cracks in the concrete wall with the fine cement particles, and then, as a second step, the cement mixing rate of the cement mixture is gradually increased to gradually increase the concrete wall. The cement mixture is injected through the injection hole until the water leakage to the inside stops, and as a third step, after the water leakage to the inside of the concrete wall stops, the coagulant is mixed into the injected cement mixture. A cement solidification layer is provided on the outside of the concrete wall of the water leakage part to complete the water stop around the opening.

For the injection of the water blocking material, an adjustable injection pipe or a packer pipe having a portion that can be expanded in response to a change in the diameter of the injection hole is used. That is, two forked short pipes are connected to one end of a hollow pipe having a length substantially equal to the thickness of the concrete wall via a branch portion, and a valve is attached to each of these distal ends. One of the forked short tubes is used for injecting a cement mixture, and the other is used for mixing a coagulant. At the outside of the other end of the hollow tube, a swelling portion made of a flexible material, which expands in response to a change in the diameter of the injection hole, is attached. In addition, the injection pipe is prevented from slipping out of the injection hole, and is closely fitted to each other so that the injection material does not leak out from between the inner wall of the injection hole and the injection pipe. When removing the injection tube from the hole,
The bulging portion is reduced and removed from the inner wall of the injection hole, so that the injection tube can be easily removed.

[0008] Since the present invention is configured as described above, even if a large amount of water is generated in the underground structure, the leakage is temporarily stopped and frozen by injecting the frozen material from around the leaked portion. Since the cement mixture and the coagulation liquid are injected according to the melting of the portion, effective water stoppage is performed. In addition, the injection pipes of the cement mixture liquid and the coagulation liquid used in the above-mentioned water stoppage method can be used for injection holes of different diameters within a certain range, so that quick and accurate injection work can be performed using injection pipes of the same diameter. I can do it.

[0009]

1 and 2 show conceptual diagrams of a freeze-stopping method according to the present invention. FIG. 1 is a front view of a leak point of a concrete wall. When water is to be shut off from a large-diameter opening 1 of a concrete wall that is springing, as a primary treatment,
A large number of holes are formed on the circumference surrounding the opening 1 at intervals of about 40 cm from each other to form small-diameter holes 2 penetrating the concrete wall and reaching the outside. The diameter of the small diameter hole 2 is 30-50mm
It is. After inserting the injection tube 3 into the small-diameter hole 2 and fixing it, the cryogen is injected.

[0010] As a freezing method, a refrigerant such as liquid nitrogen is poured into an injection pipe and directly sprayed on the ground outside the concrete wall to freeze for a short period of time. 30
℃ cooled through a small-diameter hole 2 by a pump,
It is sent to the ground outside the concrete wall, and the portion surrounding the opening 1 is frozen from outside the concrete wall toward the inside. The hatched portion in FIG. 2 shows the opening 1 and the small-diameter hole 2 after freezing.

FIG. 3 shows an embodiment of an injection pipe used for the freeze-stopping method according to the present invention. The injection pipe 3 is provided with one end of a hollow pipe 4 having a length corresponding to the thickness of a concrete wall, and two short pipes 5 and 5 are attached to one end of a hollow pipe 4. 6 is attached. On the inner side of the branch portion of the hollow tube, a larger-diameter thread portion 7 having a thread groove formed on the outer surface.
Is formed, and a nut 8 having a length substantially equal to the length of the screw portion is attached to that portion. A collar 9 having an inner diameter slightly larger than the outer diameter of the hollow tube is fitted into the central portion of the hollow tube 4. The collar 9 is movable in the axial direction of the hollow tube by rotating the nut 8 at the branch portion. As shown in FIG. 4, the injection tube 3 only needs to be long enough to be inserted into a small-diameter hole by 5 to 10 cm.

A rubber tube 10 having a central hole and a desired outer diameter is fitted into the distal end portion of the hollow tube 4 so as to be fitted on the outer surface of the hollow tube 4. The inner end of the rubber tube 10 is in contact with the front end of the collar 9 via a perforated disk-shaped washer 11, and the outer end of the rubber tube 10 is a screw engraved at the front end of the hollow tube. A nut 13 screwed to the portion 12 is fixed so as not to come out of the hollow tube. Several types of rubber cylinders 10 having an outer diameter of about 1.5 to 2 times the outer diameter of the hollow tube 4 are prepared.

A rubber cylinder 10 having an outer diameter slightly smaller than the inner diameter of the small-diameter hole 2 is selected, and the injection pipe 3 attached to the distal end portion of the hollow tube 4 by the nut 13 is inserted into the small-diameter hole. . After inserting the injection tube 3 into the small-diameter hole, the nut inside the branch portion of the tube exposed to the outside of the hole is rotated to move the collar in the axial direction of the hollow tube, and through the washer. Press the rubber cylinder in the axial direction. As a result, the rubber cylinder 10 is squeezed in the axial direction, and as a result, swells in the circumferential direction and is brought into close contact with the inner wall surface of the small-diameter hole 2.
In addition to being stably fixed in the inside, the space between the small-diameter hole 2 and the injection pipe 3 is sealed, so that spring water, discharge water and the like are stopped, and leakage of the injected cryogen or the like is also eliminated.

Next, as a second treatment, after the spring water or discharge water from the opening 1 is frozen, a large number of small-diameter small-diameter holes 2 for injecting the freezing agent further penetrate outside the concrete wall. The small-diameter hole 14 for injecting the water-stopping material is drilled, and the water-stopping material is injected from the small-diameter hole 14 within the time until the frozen portion is thawed. The injection of the water-stopping material is started by using the injection pipe 3 and fixing the injection pipe 3 in the small-diameter hole 14 by the operation procedure described above.

Injecting the water-stopping material, first, at a pressure of ³ to 5 kg / cm ² , a cement injection solution in which only cement is mixed with water at a cement mixing ratio slightly higher than that of water, and fine cement is injected. The first step of clogging minute cracks from the outside to the inside of the concrete wall by the particles, and gradually increasing the cement mixing ratio of the cement mixture gradually, the leakage of the cement mixture to the inside of the concrete wall is reduced. A second step of injecting the outside of the concrete wall through the through hole until stopping, and after the water leakage to the inside of the concrete wall has stopped, a coagulant is mixed into the injected cement mixture and the cement solidified layer is formed on the outside of the leaking concrete wall. To complete the leakage stoppage. FIG. 4 shows a cross section of the concrete wall in a state where a cement solidification layer is formed on the outside of the concrete wall and water leakage has stopped.

[0016]

The present invention is configured as described above.
By performing the water stopping method stepwise while simultaneously using the freezing method, it is possible to effectively stop a large amount of spring water or discharge water from a hole having a large diameter of 100 mm or more. For this purpose, the equipment used for the conventional freezing method for the ground was used, and the standard injection pipe for the waterproof material was prepared. By simply preparing a plurality of bulging portions made of rubber cylinders, etc., having an outer diameter matching the small diameter hole for injection, freezing and waterproofing using injection holes of various scales becomes possible, is there.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram of a freeze-stopping method according to the present invention, showing a primary treatment state when a water leaking portion of a concrete wall is viewed from the front.

FIG. 2 shows a secondary treatment state when a water leaking point of a concrete wall is viewed from the front.

FIG. 3 shows a sketch of an embodiment of an injection pipe used for the freeze-stopping method of the present invention.

FIG. 4 is a cross-sectional view of the concrete wall in a state where a cement solidification layer is formed on the outside of the concrete wall and water leakage has stopped.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Opening part 2 Small diameter hole 3 Injection pipe 4 Hollow pipe 5 Short pipe 6 Valve 7 Screw part 8 Nut 9 Collar 10 Rubber cylinder 11 Washer 12 Thread part 13 Nut 14 Small diameter hole

────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] October 20, 1998 (1998.10.
20)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claim 2

[Correction method] Change

[Correction contents]

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0003

[Correction method] Change

[Correction contents]

[0003]

As a countermeasure against such flooding, the present inventor has invented a method of stopping water for a concrete underground structure as disclosed in the specifications of Japanese Patent Nos. 1833264 and 2777249. And implemented it. In summarizing these inventions, after the water from the jet port spouting through the through hole opened on the inner side surface of the wall is temporarily fixed by closing the jet port, the cement mixture is supplied with 3 to 5 kgf / cm ^2.
Injection into the through hole from the spout with the pressure of the above, the cement mixture is pressed against the outer wall of the water leaking part by the pressure of the groundwater on the outer wall, forming a cement solidified layer that spreads on the outer surface of the wall. It is characterized by water. Such a water stoppage method is effective for spring water of about 200 liters / minute. However, when the spring water is larger than that, it is spouting from a large-diameter opening of 100 mm or more. In this case, it becomes difficult to inject the cement mixture from the opening against the pressure of the discharge water.

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0006

[Correction method] Change

[Correction contents]

[0006] The injection of the waterproof material is performed as follows. That is, as the first step, only cement is mixed with water in frozen soil or water outside the concrete wall through the through-hole at a pressure of ^{3 to 5} kgf / cm ² at a cement mixing rate slightly higher than that of water. The mixed cement mixture is injected to block the fine cracks in the concrete wall with the fine cement particles, and then, as a second step, the cement mixing rate of the cement mixture is gradually increased to gradually increase the concrete wall. The cement mixture is injected through the injection hole until the water leakage to the inside stops, and as a third step, after the water leakage to the inside of the concrete wall stops, in the injected cement mixture,
A coagulant is mixed in and a cement coagulation layer is provided on the outside of the concrete wall of the water leakage section to complete the water stop around the opening.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0015

[Correction method] Change

[Correction contents]

[0015] The injection of the water-stopping material is first performed at 3 to 5 kgf / cm ^2.
Injecting a cement injection solution in which only cement is mixed with water at a cement mixing ratio slightly higher than that of water at a pressure of 1st, and the fine cracks from the outside to the inside of the concrete wall are clogged by the fine cement particles. And a second step of gradually increasing the cement mixing ratio of the cement mixture in a stepwise manner and injecting the cement mixture through the through-holes to the outside of the concrete wall until water leakage to the inside of the concrete wall stops, After the water leakage to the inner surface of the concrete wall stops, a coagulant is mixed into the injected cement mixture to form a cement coagulation layer on the outside of the concrete wall of the water leaking part, thereby completing the water leakage stoppage. FIG. 4 shows a cross section of the concrete wall in a state where a cement solidification layer is formed on the outside of the concrete wall and water leakage has stopped.

Claims (5)

[Claims] 1. A large number of frozen material injection holes are drilled at predetermined intervals around a large-diameter opening of a concrete wall where spring water is flowing through the concrete wall, and the frozen material is injected from the injection hole. Then, the spring water or the discharge water discharged from the opening is frozen, and after the spring water or the discharge water from the opening is frozen, a water-stopping material injection hole is newly provided between the frozen material injection holes. The hole is cut through the concrete wall, and within the time until the frozen part is thawed, the water-stopping material is injected from the water-stopping material injection hole, and the flowing water part on the back of the wall is hardened. Water-stopping method for concrete underground structures using the freezing method. 2. Injecting a water-stopping material as a first step into the frozen soil or the water outside the concrete wall through the through hole at a pressure of ^{3 to 5} kg / cm ^{2 at} a pressure of ^{3 to 5} kg / cm ^2. At the mixing rate, a cement mixture in which only cement is mixed with water is injected to cause fine cement particles to clog fine cracks in the concrete wall, and then as a second step,
The cement mixing rate of the cement mixture is gradually increased, and the cement mixture is injected through the injection hole until the water leakage to the inside of the concrete wall stops, and as a third step, water leakage to the inside of the concrete wall is performed. The method according to claim 1, wherein after stopping, a coagulant is mixed into the injected cement mixture to provide a cement coagulation layer on the outside of the concrete wall of the water leaking part to complete the water stop around the opening. Water stoppage method for concrete underground structures using freezing method. 3. A hollow pipe having a length substantially equal to the thickness of a concrete wall, and two forked short pipes connected to one end of the hollow pipe via a branch portion. The valve is attached to each, and the other end of the hollow tube is expanded in accordance with the change in the diameter of the injection hole, and is expanded in response to the change in the diameter of the injection hole. An adjustable injection pipe with a swelling part made of flexible material that can be used for the waterproofing method of concrete underground structures combined with the freezing method. 4. The injection tube according to claim 3, wherein the bulging portion is formed of a rubber cylinder that can expand and contract in an outer circumferential direction. 5. The injection pipe has a bifurcated short pipe attached to one end of a hollow pipe having a length corresponding to the thickness of a concrete wall, and a valve for opening and closing a pipe line in each of the short pipes. At the inside of the branch portion of the hollow tube, a larger diameter screw portion with a thread groove formed on the outer surface is formed, and a nut approximately equal to the length of the screw portion is attached to that portion, and the hollow tube is attached. A collar having an inner diameter slightly larger than the outer diameter of the hollow tube is fitted into a central portion of the hollow tube, and the collar is movable in an axial direction of the hollow tube by rotating a nut of the branch portion. At the tip of the empty tube, a rubber tube having a desired outer diameter and a central hole fitted to the outer surface of the hollow tube are fitted, and the inner end of the rubber tube has a perforated disk shape. The end of the rubber tube comes into contact with the tip of the collar via the washer. The injection tube according to claim 4, wherein the injection tube is fixed so as not to come out of the hollow tube by a nut that is screwed into a thread portion engraved on the portion.