JP2016130436A - Repair structure for concrete structure, and construction method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a repair structure for a concrete structure that is low in construction costs and high in work efficiency, ensuring water cut-off even when an injection hole does not cross a crack or when there is a large void on a rear surface of concrete.SOLUTION: A repair structure for a concrete structure comprises in an area subject to water cut-off on lining concrete 2: a plurality of non-penetrating injection holes 6 formed leaving an interval in the area subject to water cut-off, from a front surface side of the lining concrete 2; and water cut-off parts 8a, 8b, 9a, 9b, 10 formed to almost fill each of the injection holes 6, and to spread from each of the injection holes 6 as starting points to infiltrate into a minute gap in the lining concrete 2. The water cut-off part is formed of a water cut-off material containing a base compound having viscosity of 5 mPa s or less.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a repair structure for a concrete structure that repairs water leakage that occurs in a concrete structure such as a tunnel, an underground facility, or a building, and a method for constructing the repair structure.

  As a repair method for stopping the leakage of water in a concrete structure, as shown in FIG. 6, the crack 21 generated on the concrete wall 20 is at a predetermined angle so as to cross the crack 21 and about 2/3 of the wall thickness. The injection hole 22 is formed up to a deep position, and the surface layer portion of the concrete wall 20 of the crack 21 is closed with the quick-setting cement 23. In this state, a high-viscosity waterstop material of 700 to 1400 mPa · s is formed as the injection hole 22. There is one in which a water stop portion 24 is formed so as to be injected into the crack 21 at a high pressure of 10 to 20 MPa and foamed by a chemical reaction with water to fill the injection hole 22 and the crack 21 (see Patent Document 1). In the figure, 31 is soil, and 32 is a back cavity where water between the concrete wall 20 and the soil 31 exists.

  Further, as shown in FIG. 7, a through hole 25 penetrating to the back surface is formed in the concrete wall 20, and a water-stopping material having a specific gravity close to water is injected into the through hole 25 to radiate along the back surface of the concrete wall 20. There is also a method of forming a water-stopping film 26 that is diffused over a wide area and hardened on the back side of the concrete wall 20 (see Patent Document 2). The water blocking film 26 is intended to stop water even at locations where there are many leaking cracks 21 or where the water leakage path cannot be specified.

JP 2004-251010 A JP 2014-208970 A

  By the way, in the construction method in which the injection hole 22 is formed at a predetermined angle so as to cross the crack 21 in FIG. 6 and the water-stopping material is filled into the crack 21, the injection hole 22 is formed so as not to cross the crack 21. In this case, the cracks 21 are not filled with the water-stopping material and are not stopped. The success or failure of this crossing is difficult to discriminate in the pressure control of the injection pressure of the water-stopping material, because the pressure rises in the same way even when the normal injection is completed or when the injection hole is not cracked. It is. Furthermore, in order to perform high-pressure injection, it is necessary to prepare an expensive high-pressure pump, and if high-pressure injection is performed, there is a possibility that a water-stopping material will be ejected from an unexpected location, which requires troublesome construction management. There is also.

  On the other hand, in the construction method in which the water blocking film 26 is formed on the back side of the concrete wall 20 in FIG. 7, the water blocking is not hindered by crossing the crack 21 of the injection hole 22 described above, but the back cavity is large. In this case, the water-stopping material does not stay around the outlet of the through-hole 25 and flows out and disappears, resulting in another problem that the water-stopping film 26 cannot be formed. Furthermore, when the wall thickness of the concrete wall 20 is large, there is a problem that a great deal of labor is required for the drilling operation of the through hole 25.

  The present invention is proposed in view of the above problems, and can reliably stop water even when the injection hole does not cross the crack or there is a large cavity on the back of the concrete, and the construction cost is low and the construction efficiency is low. An object of the present invention is to provide a concrete structure repair structure and its construction method that are superior to the above.

The repair structure for a concrete structure of the present invention is formed in a concrete water-stop target region in a non-penetrating manner from the surface side of the concrete, and a plurality of injection holes provided at intervals in the water-stop target region, and the injection hole And a water stop portion provided so as to diffuse from each of the injection holes as a starting point and penetrate into the micro voids of the concrete, and the water stop portion has a viscosity of 5 mPa · It is formed by the water stop material comprised from the main ingredient below s.
According to this, the water stop material penetrates the entire water stop target area of the concrete, and the entire water stop target area including the water stop portion that has penetrated into the minute gaps is stopped, so the injection hole crosses the crack. Even if not, since the penetrated water-stopping material reaches the crack and is almost filled, the water can be reliably stopped even when the injection hole does not cross the crack. Further, since the water stop portion is formed by penetrating into the concrete itself, the water can be reliably stopped regardless of the size of the cavity on the back surface of the concrete. In addition, when pressure-stopping a water-stopping material composed of a main agent having a viscosity of 5 mPa · s or less, the water-stopping material can be diffused and penetrated into microscopic gaps by injecting under pressure with an inexpensive low-pressure pump. Therefore, an expensive high-pressure pump having high-pressure performance is unnecessary, and construction can be performed at low cost. Furthermore, since the water-stopping material can be sufficiently diffused and permeated by low-pressure pressurization without deeply drilling the injection hole, the labor of the drilling operation can be reduced and the construction efficiency can be increased. Furthermore, the water-stopping material is not ejected from an unexpected location by low-pressure pressurization, so that the labor required for construction management can be reduced and the load imposed on the concrete to be repaired by pressurization can be reduced.

The repair structure for a concrete structure according to the present invention is characterized in that the position of the tip of each of the injection holes is a position of 1/2 or less in the thickness direction of the concrete from the concrete surface side.
According to this, the labor of a drilling operation can be further reduced and the construction efficiency can be further increased.

In the repair structure of a concrete structure of the present invention, the waterstop material has a viscosity of 1 to 5 mPa · s, a first main agent mainly composed of sodium acrylate having a specific gravity of 1.075 ± 0.025, and a viscosity of 1 to 5 mPa. -It is characterized by being comprised from the 2nd main ingredient which has sodium persulfate of specific gravity 1.025 +/- 0.025 as a main component, and the hardening regulator which adjusts hardening time.
According to this, the hardened water-stopping part can be made of a material that is rich in elasticity, adhesion, and adhesion, and is not leached by water or organic matter. When the concrete back is ground, the ground is stabilized. It is also possible to expect. In addition, since the specific gravity of the water-stopping material is close to that of water, the water-stopping material can be properly distributed without floating or sinking in the water even when water leakage actually occurs. Further, by adjusting the addition amount of the curing modifier, it is possible to adjust the gel time on the spot according to the on-site situation.

The repair structure for a concrete structure according to the present invention is characterized in that the water stop portion is provided over substantially the entire water stop target area of the concrete.
According to this, it is possible to perform water stop treatment without leaking over almost the entire water stop target area of concrete, including places where cracks are likely to occur in the near future. It is possible to eliminate the dignity of the water that turns into another crack and leaks, and there is a separate water stop treatment.

The concrete structure repair method according to the present invention is a method for constructing a concrete structure repair structure according to the present invention, wherein the injection hole is formed, the injection hole is formed, and the injection hole is formed. A first step of installing a packer at the mouth of the injection hole that can block the communication between the back of the hole and the outside of the hole, and a sodium acrylate having a viscosity of 1 to 5 mPa · s and a specific gravity of 1.075 ± 0.025 as a main component Mixing the first main agent, a second main agent containing sodium persulfate having a viscosity of 1 to 5 mPa · s and a specific gravity of 1.025 ± 0.025 as a main component, and a curing regulator for adjusting the curing time. As a water material, a second step of injecting into the injection hole from the communicating portion at the mouth of the injection hole at a pressure of 200 kPa or less, and a third step of confirming the seepage of the water stop material from the surface of the concrete, It is characterized by having The
According to this, the water-stop part provided by curing the water-stop material can be made of a material with high elasticity, adhesion, adhesion, and no leaching due to water or organic matter. It is possible to stabilize the ground. In addition, since the specific gravity of the water-stopping material is close to that of water, the water-stopping material can be properly distributed without floating or sinking in the water even when water leakage actually occurs. Further, by adjusting the addition amount of the curing modifier, it is possible to adjust the gel time on the spot according to the on-site situation. In addition, by applying pressure injection of 200 kPa or less, it is possible to minimize the burden on the concrete to be repaired by pressure injection while ensuring sufficient diffusion and penetration of the water-stopping material. Moreover, the completion of the injection can be recognized efficiently by the seepage of the water-stopping material from the concrete surface, and the construction efficiency can be further improved.

  According to the repair structure of a concrete structure of the present invention or the construction method thereof, water can be reliably stopped even when the injection hole does not cross the crack or there is a large cavity on the back of the concrete, and the construction cost is low. Construction can be performed with excellent construction efficiency.

Partial cross-sectional explanatory drawing which shows the construction middle state of the repair structure of the concrete structure of embodiment by this invention. The longitudinal cross-sectional view which shows the repair structure of the concrete structure of embodiment by this invention. The longitudinal cross-sectional view which shows the water stop target area | region of the concrete which is leaking water. The longitudinal cross-sectional view which shows the state which perforated the injection hole in the water stop object area | region of the concrete of FIG. 3, and gave the seal | sticker. The longitudinal cross-sectional view which shows the state which installed the packer in the injection hole from the state of FIG. 4, and inject | poured the water stop material. The fragmentary longitudinal cross-section which shows the repair structure of a prior art example. The fragmentary longitudinal cross-section which shows the conventional repair structure of another example.

[Repair structure of concrete structure of embodiment and construction method thereof]
The concrete structure repair structure according to the embodiment of the present invention repairs the lining concrete 2 of the tunnel 1 as shown in FIG. Water is present in the back cavity 4 between the soil 3 outside the lining concrete 2 and the lining concrete 2, and the repair structure is configured to stop water leakage from the crack 5 generated in the lining concrete 2. Is provided.

  In the repair structure of this embodiment, as shown in FIG.1 and FIG.2, the injection hole 6 is formed in the water stop target area | region of the lining concrete 2 from the surface side of the lining concrete 2 without penetrating. A plurality of non-penetrating injection holes 6 are provided at intervals in the water stop target region, and the tip positions of the respective injection holes 6 extend from the surface side of the lining concrete 2 in the thickness direction of the lining concrete 2. It is formed so as to be a position of 1/2 or less, and preferably is formed to be a position of 1/2 or less in the thickness direction and 1/3 or more from the viewpoint of wider diffusion and penetration of the water-stopping material. .

  A packer 7 is installed at the mouth of each injection hole 6, a water stop portion 8 a at a deeper portion than the packer 7 of the injection hole 6, and a water stop portion 8 b at a portion before the packer 7 of the injection hole 6. Is provided so as to substantially fill the injection hole 6. Further, a water stop portion 9 a is provided so that the crack 5 is filled in the portion where the injection hole 6 crosses the crack 5, and the water stop is provided so as to cover the opening of the crack 5 on the back side of the lining concrete 2. A portion 9b is provided. Further, a water stop portion 10 is provided so as to diffuse from each of the injection holes 6 and penetrate into the minute gaps of the lining concrete 2 in the water stop target region.

  The water stop portions 8a and 8b, the water stop portions 9a and 9b, and the water stop portion 10 are formed of a low-viscosity, high-permeability water stop material composed of a main agent having a viscosity of 5 mPa · s or less. Are, for example, a first main ingredient mainly composed of sodium acrylate having a viscosity of 1 to 5 mPa · s and a specific gravity of 1.075 ± 0.025, and persulfuric acid having a viscosity of 1 to 5 mPa · s and a specific gravity of 1.025 ± 0.025. It is preferable to comprise from the 2nd main ingredient which has sodium as a main component, and the hardening regulator which adjusts hardening time.

  The water stop portions 8a, 8b, 9a, 9b, and 10 are provided over substantially the entire water stop target region of the lining concrete 2, and in the example of FIG. The water stop portion 10 provided so as to penetrate into the gap is formed so as to partially overlap the adjacent water stop portion 10.

  When constructing the repair structure for a concrete structure of this embodiment, as shown in FIGS. 3 and 4, drilling is performed in the water stop target area of the lining concrete 2 where the water leakage LW is generated from the crack 5. Thus, the injection hole 6 is formed. In the example of FIG. 4, the injection hole 6 is formed so as to incline downward from the construction surface of the surface of the lining concrete 2 toward the inside of the lining concrete 2, and the tip position is the thickness of the lining concrete 2. The injection hole 6 is formed so as to be at a position of ½ or less in the vertical direction, and the injection hole 6 that traverses the crack 5 and the injection hole 6 that is provided at a place where there is no crack 5 are formed. At this time, for the required crack 5 such as the crack 5 in the water stop target region or the crack 5 in which the water stop material is directly injected across the injection hole 6, the opening on the surface side of the lining concrete 2 is covered. The sealing material 15 is provided by coating or sticking.

  Then, as shown in FIG. 5, a packer 7 is installed at the mouth of the injection hole 6, which can block communication between the depth of the injection hole 6 and the outside of the hole. The packer 7 is appropriate, for example, one that fills the bag with an inflating material after the installation into the injection hole 6 and expands, or one that tightens and expands the expansion rubber.

  Then, a water stop material is inject | poured in the injection hole 6 which installed the packer 7 with the pressure of 200 kPa or less through the communicating part of the hole back and the hole exterior. As the water-stopping material, for example, a first main agent mainly composed of sodium acrylate having a viscosity of 1 to 5 mPa · s and a specific gravity of 1.075 ± 0.025, and a specific gravity of 1.025 ± at a viscosity of 1 to 5 mPa · s. In the case of injecting a water-stopping material composed of 0.025 sodium persulfate as a main component and a curing regulator, as shown in FIG. 1, the first main agent and the second main agent are reduced in pressure. Separately supplied by the pump 16, low pressure injection is performed in the injection hole 6 while adding and mixing a curing regulator in the vicinity of the injection hole 6 by the mixing unit 17. Then, the injection of the water-stopping material into the injection hole 6 is completed when the seepage of the water-stopping material from the surface of the lining concrete 2 has been confirmed.

  At this time, since the water-stopping material of this example is a cured acrylic resin, it is basically colorless and transparent. If the surface of the lining concrete 2 is not to be soiled by oozing, it is used as it is. When it is desired to confirm the completion of the construction, any colorant can be mixed, and coloring according to the site conditions is possible.

  With the injection of the water-stopping material into the injection hole 6, the water-stopping material filled in the injection hole 6 is cured after a predetermined time and the water-stopping portion 8a is formed in the injection hole 6 that does not cross the crack 5. In addition to the formation, the water stop material injected from the injection hole 6 as a starting point diffuses and penetrates into the surrounding minute gaps to form the water stop portion 10, and further penetrates to the front of the packer 7 in the injection hole 6. The water stop 8b is formed.

  In addition, in the injection hole 6 crossing the crack 5, a part of the water-stopping material injected into the injection hole 6 flows outward from the opening on the back side of the lining concrete 2 of the crack 5, and the opening is opened. A water stop portion 9b is formed so as to cover, and a water stop portion 9a is formed so as to fill the crack 5 between the water stop portion 9b and the sealing material 15, and further, a water stop material is formed in the injection hole 6. The water-stopping portion 8a is formed by filling, and the water-stopping material injected from the injection hole 6 as a starting point diffuses and penetrates into the surrounding minute gaps to form the water-stopping portion 10, and further, the injection hole The water stop portion 8b is formed by penetrating and reaching the front of the packer 7 of 6.

  According to the present embodiment, the water stop portion 10 penetrates the entire water stop target region of the lining concrete 2, and the entire water stop target region including the water stop portion that has permeated the minute gaps is stopped. Even when the injection hole 6 does not cross the crack 5, the permeated water-stopping material reaches the crack 5 and is substantially filled, so that the injection hole 6 reliably stops water without crossing the crack 5. be able to. Furthermore, since the water stop portion is formed by penetrating into the lining concrete 2 itself, the water can be reliably stopped regardless of the size of the back cavity 4 of the lining concrete 2.

  In addition, when pressure-injecting a water-stopping material composed of a main agent having a viscosity of 5 mPa · s or less, the water-stopping material can be diffused to an extremely fine minute gap if pressure-injected with the pressure of an inexpensive low-pressure pump 16. An expensive high-pressure pump that can be infiltrated and has high-pressure performance is unnecessary, and can be constructed at low cost. Furthermore, since the water-stopping material can be sufficiently diffused and permeated by low-pressure pressurization without deeply drilling the injection hole 6, it is possible to reduce the labor of the drilling operation and increase the construction efficiency. Furthermore, the water-stopping material is not ejected from an unexpected part by low-pressure pressurization, so that the labor required for construction management can be reduced and the burden imposed on the lining concrete 2 to be repaired by pressurization can be reduced. .

  In addition, since the water stop portion is provided over substantially the entire water stop target area of the lining concrete 2, it is possible to perform the water stop treatment without leakage including a portion where a crack 5 is likely to occur in the near future. When the crack 5 which has actually leaked water is closed, water can turn to another crack 5 and leak, and there is no need to perform a water stop treatment separately. In particular, in this embodiment, the water-stop portion is formed of a cured acrylic resin, so that the acrylic resin swells due to water absorption, maintains an elastic state even after drying shrinkage, and repeats swelling if water is included again. Since the water is stopped by making use of the properties, there is no fear of re-forming the gap due to shrinkage of the water-stopping material after curing, and a stable and long-term water-stopping effect can be expected.

  Moreover, the 1st main ingredient which has a specific gravity of 1.075 ± 0.025 as a main component with a viscosity of 1-5 mPa · s, and a sodium persulfate with a specific gravity of 1.025 ± 0.025 with a viscosity of 1-5 mPa · s. In the case of providing a water-stop part using a water-stop material composed of a second main component mainly composed of selenium and a curing regulator that adjusts the curing time, the cured water-stop part is provided with elasticity, adhesion, and adhesion. It is possible to make the material rich in force and not to be leached by water or organic matter, and when the back surface of the lining concrete 2 is the ground, the ground can be stabilized. Moreover, since a water stop part becomes alkaline, the soundness of the neutralized lining concrete 2 can be restored | restored. In addition, since the specific gravity of the water-stopping material is close to that of water, the water-stopping material can be properly distributed without floating or sinking in the water even when water leakage actually occurs. Further, by adjusting the addition amount of the curing modifier, it is possible to adjust the gel time on the spot according to the on-site situation.

  Moreover, when constructing the repair structure, the seepage of the water-stopping material from the surface of the lining concrete 2 can be visually observed to recognize the completion of the injection, and the construction efficiency can be further improved. .

  In addition, in said Example, the part which flowed outside from the opening by the side of the back surface of the lining concrete 2 of the crack 5 and the water stop part 9b was formed so that the opening might be covered was described. However, according to the present invention, it is not an essential requirement that the injection hole 6 intersects and fills the crack 5, and the water-stopping material is diffused and permeated over a wide range. In the example shown, as a countermeasure when the injection hole 6 hits the crack 5 and does not return to the surface side, a hardening accelerator is additionally added to the waterstop material and used to form the waterstop portion 9b. This process is not necessary when the injection hole 6 does not hit the crack 5. Alternatively, depending on the field conditions, the amount of the curing accelerator used is suppressed, and a water-stopping material is actively poured into the back cavity 4 on the back side using the cracks 5 penetrating the lining concrete 2. You may fill with a water stop material.

[Modifications of Embodiment, etc.]
The invention disclosed in this specification is specified by changing these partial configurations to other configurations disclosed in this specification, in addition to the respective inventions, embodiments, and examples, to the extent applicable. Those that are specified by adding other configurations disclosed in this specification to these configurations, or those that have been identified by deleting these partial configurations to the extent that partial effects can be obtained and specifying them The following modifications are also included.

  For example, the application object of the repair structure of the concrete structure or the construction method of the present invention is not limited to the tunnel lining concrete 2 but can be applied to repair of various concrete structures such as underground facilities and buildings. Moreover, if the water stop material used by this invention is a water stop material comprised from the main ingredient with a viscosity of 5 mPa * s or less, it is appropriate within the meaning of the present invention.

  The present invention can be used, for example, when water leakage generated in a concrete structure such as a tunnel, an underground facility, or a building is stopped.

DESCRIPTION OF SYMBOLS 1 ... Tunnel 2 ... Covering concrete 3 ... Soil 4 ... Back cavity 5 ... Crack 6 ... Injection hole 7 ... Packer 8a, 8b, 9a, 9b, 10 ... Water stop part 15 ... Sealing material 16 ... Low pressure pump 17 ... Mixing unit LW ... Leakage 20 ... Concrete wall 21 ... Crack 22 ... Injection hole 23 ... Quick setting cement 24 ... Water stop part 25 ... Through hole 26 ... Water stop film 31 ... Soil 32 ... Back cavity

Claims (5)

A non-penetration formed from the surface side of the concrete to the water stop target area of concrete, and a plurality of injection holes provided at intervals in the water stop target area,
A water stop portion provided so as to substantially fill each of the injection holes, and provided so as to diffuse from each of the injection holes as a starting point and penetrate into the minute voids of the concrete,
The repair structure for a concrete structure, wherein the water stop portion is formed of a water stop material composed of a main agent having a viscosity of 5 mPa · s or less.   The repair structure for a concrete structure according to claim 1, wherein a tip position of each of the injection holes is a position that is 1/2 or less of a thickness direction of the concrete from a surface side of the concrete.   The waterstop material has a viscosity of 1 to 5 mPa · s and a specific gravity of 1.075 ± 0.025 as a main component, and a viscosity of 1 to 5 mPa · s and a specific gravity of 1.025 ± 0.025. 3. The repair structure for a concrete structure according to claim 1, comprising: a second main agent comprising sodium persulfate as a main component and a curing regulator for adjusting a curing time.   The repair structure for a concrete structure according to any one of claims 1 to 3, wherein the water stop portion is provided over substantially the entire water stop target area of the concrete. A construction method for repairing a concrete structure according to any one of claims 1 to 4,
A first step of forming the injection hole, and installing a packer at the mouth of the injection hole that can close the back of the injection hole and communication outside the hole;
Main component is a first main ingredient mainly composed of sodium acrylate having a viscosity of 1 to 5 mPa · s and a specific gravity of 1.075 ± 0.025, and sodium persulfate having a viscosity of 1 to 5 mPa · s and a specific gravity of 1.025 ± 0.025. A second main agent that is a component and a curing regulator that adjusts the curing time are mixed, and the water-stopping material is injected into the injection hole at a pressure of 200 kPa or less from the communicating portion at the mouth of the injection hole. Process,
And a third step of confirming the seepage of the water-stopping material from the surface of the concrete. A method for constructing a repair structure for a concrete structure, comprising:

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