JP2006118214A - Filler for tunnel cavity, and tunnel excavating method using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a filler for a tunnel cavity, and a tunnel excavating method using the filler for the tunnel cavity that can suppress the collapse of the natural ground without causing hindrance to the construction of a tunnel in excavating the tunnel in the natural ground where self-support is difficult. <P>SOLUTION: In a shield tunneling method for constructing the tunnel T by disposing segments 10 assembled inside a shield machine 30, in the natural ground G while excavating the natural ground G by the shield machine 30, the filler 12 for the tunnel cavity formed of an acrylic material, is filled in the cavity K3 formed between the periphery of the shield machine 30 and an excavated face K2 of the natural ground G as the tunnel is excavated. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a tunnel gap filling material filled in a gap formed between a tunnel excavator and a natural ground, and a tunnel excavation method using the same.

  A tunnel excavator such as a shield machine or a tunnel boring machine (hereinafter sometimes referred to as “TBM”) is basically a cutter head for excavating natural ground and a power source of the tunnel excavator disposed behind the cutter head. And a shield part for protecting jacks and the like.

  Such a tunnel excavator is formed so that the outer diameter (outer shape) of the shield portion is smaller than the excavation diameter (excavation shape) of the normal cutter head. The difference between the excavation diameter of the cutter head and the outer diameter of the shield part (hereinafter sometimes referred to as “excess excavation part”) corresponds to a curved line shape, deformation of the natural ground, an expansive natural ground, and the like.

  However, tunnel construction in unconsolidated grounds and cracked rocks such as rocks with many cracks may cause troubles due to the collapse of the ground due to the presence of overexcavations. It was. In particular, when the excavation work is interrupted for some reason in such a difficult ground, the collapsed sediment is accumulated, consolidated, and compacted to restrain the tunnel excavator and resume the excavation. There was a case that could not be done.

For this reason, when excavating a tunnel with a tunnel excavator in such a natural ground that is difficult to stand by itself, for example, by injecting an injection material such as cement milk, water glass, and urethane foam into the natural ground, In some cases, they were independent and prevented from collapsing.
In Patent Document 1, in tunnel excavation by TBM, a flat rectangular plate formed so as to cover the upper half of the shield part is disposed, and the bag is attached to the air. A method of supporting a natural ground by inflating it by injecting fluid such as water is described.
JP 2001-40994 A ([0012]-[0024], FIG. 2 to FIG. 3)

However, the former method using the injection material has a problem that adhesion to the tunnel excavator in the natural ground including the injection material increases, which may adhere to the outer peripheral surface of the excavator and hinder the excavation. Had a point. In addition, there has been a problem in that excavation may be difficult because the earth and sand containing the injection material adheres to the earth and sand intake and cannot be carried out in the chamber of the tunnel excavator.
In the latter case, it is possible to protect the excavator by preventing the collapse of the ground during construction, but if the excavation work is interrupted for some reason, the fall of the face on the front of the excavator is prevented. Because it was not possible to do this, it was necessary to make the ground stand self-supporting with an injection material. For this reason, when excavation is resumed, the ground containing the injection material is dug, so that the earth and sand containing the injection material may adhere to the chamber of the excavator, which may hinder the construction. It was.

  The present invention has been made to solve the above-mentioned problems, and in tunnel excavation in a natural ground where it is difficult to stand on its own, it is possible to suppress the collapse of the natural ground without causing an obstacle to the construction of the tunnel. Another object is to propose a tunnel gap filler and a tunnel excavation method using the filler.

  In order to solve the above problems, the invention according to claim 1 is a filler for a tunnel gap that is filled in a gap formed between a periphery of a tunnel excavator and a natural ground, and the tunnel gap The filler for use is a mixture of an aqueous monovalent or divalent metal salt of acrylic acid, an aqueous solution of an aluminum water-soluble salt, and an aqueous bisulfite solution.

  The invention according to claim 2 is the tunnel void filler according to claim 1, wherein the metal salt aqueous solution is 1 and the aluminum water-soluble salt aqueous solution is 0.9 or more and 1. 5 or less, wherein the bisulfite aqueous solution is mixed at a ratio of 0.9 to 1.5.

  If such a filler for a tunnel gap is filled in a gap (overexcavated portion) formed between a tunnel excavator and a natural ground, the filler for the tunnel gap is cured with a predetermined strength in the gap. It is also possible to suppress the collapse of the natural ground even when excavating a tunnel in the unconsolidated ground. Further, the tunnel gap filler constituted by the above-mentioned composition has a weak adhesion with iron, and therefore does not adhere to the outer peripheral surface of the tunnel excavator and does not hinder the thrust of the tunnel excavator. . In addition, when tunnel excavation is interrupted for some reason, if the gap between the face face and the tunnel excavator is filled with a filler for tunnel gap, the face collapse is suppressed, and when excavation is resumed, The earth and sand containing the filler for the tunnel gap does not adhere in the chamber and does not hinder the construction.

  Here, examples of the monovalent or divalent metal salt aqueous solution of acrylic acid according to the present invention include alkali metal salts, alkaline earth metal salts, sodium salts, and magnesium salts of acrylic acid. Examples of the aqueous solution of the aluminum water-soluble salt include aluminum acrylate, aluminum chloride, aluminum nitrate, aluminum sulfate, alum, sodium alum, aluminum acetate, aluminum lactate, polyaluminum chloride, polyaluminum sulfate chloride, and the like. Furthermore, examples of the aqueous bisulfite solution include alkali metal salts, sodium bisulfite salts, and potassium bisulfite salts.

  According to a third aspect of the present invention, an excavation step of excavating a natural ground with a tunnel excavator, and an air gap formed between the tunnel excavator and the natural ground in the excavation step is made of an acrylic material. A tunnel excavation method comprising: a filling step of filling a filler for a tunnel gap.

  The invention according to claim 4 is the tunnel excavation method according to claim 3, wherein the filling step includes a monovalent or divalent metal salt aqueous solution of acrylic acid, an aqueous solution of aluminum water-soluble salt, And a step of mixing the aqueous bisulfite solution to form the tunnel void filler.

  The invention according to claim 5 is the tunnel excavation method according to claim 4, wherein the aqueous metal salt solution is 0.9 and the aqueous aluminum salt solution is 0.9 or more and 1.5 or less. The tunnel void filler is constituted by mixing the bisulfite aqueous solution at a ratio of 0.9 to 1.5.

  Such a tunnel excavation method is applied to the present invention from a hole formed in a shield part of a tunnel excavator, an opening, a back surface, etc. in a gap formed between a tunnel excavator such as a shield machine or a tunnel boring machine and a natural ground. By filling the tunnel gap filling material, the tunnel excavation can be performed while preventing the excavation of the tunnel excavator and the collapse of the natural ground is suppressed, so that stable tunnel construction is possible. That is, the filler for tunnel voids made of an acrylic material composed of the above-mentioned composition has a weak adhesive force with iron and exhibits a predetermined strength, so that it hardens without adhering to the tunnel machine, It is possible to suppress the collapse of the mountain.

In addition, by using the tunnel gap filling material as it is as a backfilling material, it is possible to reduce the amount of backfilling material to be filled on the back surface of the segment after assembling the segment, which is economically superior.
In addition, since the tunnel gap filler has a weak adhesive force with iron, when the construction is interrupted, the gap between the face surface and the cutter head of the tunnel excavator is filled to a predetermined strength. The hardened tunnel gap filler prevents the face from collapsing, and after the excavation resumes, the tunnel gap filler is carried out with the earth and sand without adhering inside the tunnel excavator, which may hinder the construction. Not preferred.

  Furthermore, the invention described in claim 6 is the tunnel excavation method according to claim 4 or claim 5, wherein the filling step includes the monovalent or divalent metal salt aqueous solution of the acrylic acid, A step of individually feeding an aqueous solution of an aluminum water salt and the aqueous bisulfite solution through three pipe lines, a monovalent or divalent metal salt aqueous solution of the acrylic acid fed, and And a step of mixing the aqueous solution of the aluminum water salt with the aqueous bisulfite solution to fill the voids.

  In such tunnel excavation method, the tunnel gap filler that hardens early after mixing is mixed just before filling the gap, so that even in tunnel construction with a long tunnel extension, the tunnel gap filler can be cured in the middle of the piping. By proceeding, the pipeline is not blocked and construction will not be hindered.

  By the tunnel gap filling material of the present invention and the tunnel excavation method using the same, it is possible to suppress the collapse of the natural ground without causing any trouble in the tunnel construction in the tunnel excavation in the natural ground where it is difficult to be independent. Therefore, stable tunnel construction becomes possible.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described with reference to the drawings. In the description, the same reference numerals are used for the same elements, and duplicate descriptions are omitted.

<First Embodiment>
Hereinafter, a first embodiment (hereinafter, simply referred to as “first embodiment”) will be described.
FIG. 1 is a cross-sectional view showing a state of filling a gap between a shield machine, which is a tunnel excavator, and a natural ground with a tunnel gap filler according to the first embodiment. Moreover, FIG. 2 is the schematic which shows the injection apparatus of the sliding material and backfilling material of 1st Embodiment.

  In the first embodiment, as shown in FIG. 1, the shield 10 constructs the tunnel T by arranging the segments 10 assembled inside the shield machine 30 in the ground pile G while excavating the ground pile G by the shield machine 30. In the construction method, the tunnel gap filling material 12 made of an acrylic material is filled in the gap K3 formed between the periphery of the shield machine 30 and the excavation surface K2 of the natural ground G as the tunnel is dug. In the first embodiment, the shield machine 30 is used as the tunnel excavator. However, for example, a TBM (tunnel boring machine) may be used, and the tunnel excavator applied to the present invention is limited to the shield machine. Is not to be done. In the first embodiment, the segment 10 is used. However, for example, a liner may be used, and the support structure of the tunnel is appropriately selected according to the situation at the site.

In addition, the tunnel gap filler 12 filled in the gap K3 is a mixture of a monovalent or divalent metal salt aqueous solution of acrylic acid, an aqueous solution of an aluminum water-soluble salt, and a bisulfite aqueous solution.
Here, the blending of the monovalent or divalent metal salt aqueous solution of acrylic acid, the aqueous solution of the aluminum water-soluble salt and the aqueous bisulfite solution is 1: 0.9 to 1.5: 0.9 to 1. 5 is mixed.

Here, as the monovalent or divalent metal salt aqueous solution of acrylic acid, an alkali metal salt, alkaline earth metal salt, sodium salt or magnesium salt of acrylic acid is used. As the aqueous solution of the aluminum water-soluble salt, aluminum acrylate, aluminum chloride, aluminum nitrate, aluminum sulfate, alum, sodium alum, aluminum acetate, aluminum lactate, polyaluminum chloride, polyaluminum sulfate chloride and the like are used. Furthermore, as the bisulfite aqueous solution, an alkali metal salt, sodium bisulfite salt, potassium bisulfite salt or the like is used.
In addition, the density | concentration of the aluminum water salt (solid content) in the aqueous solution of the said aluminum water-soluble salt shall be in the range of 10 to 70 weight%, More preferably, it shall be in the range of 30 to 50 weight%. Moreover, the density | concentration of the bisulfite (solid content) in the said bisulfite aqueous solution shall be in the range of 0.5 to 10 weight%, More preferably, it shall be in the range of 1 to 5%.

  As shown in FIG. 1, the shield machine 30 includes a cutter head 31 that mainly excavates the natural ground G, and a shield part 32 that is located behind the cutter head 31 and protects various facilities inside the shield machine 30. It is composed of The shield machine 30 according to the first embodiment is formed in a circular cross section, and the outer diameter of the shield portion 32 is slightly smaller than the outer diameter of the cutter head 31. The shape of the shield machine 30 is not limited to a circular cross section. For example, the cross section has a rectangular shape or an elliptical shape, or a double-type cross-section or a triple-type cross-section in which a plurality of circular cross-sections are connected. Things may be used.

Inside the shield portion 32, a chamber 33 in which the earth and sand excavated by the cutter head 31 is temporarily deposited is formed on the back surface of the cutter head 31, and the earth and sand in the chamber 33 is Transported outside the tunnel T. In addition, a shield jack 35 is disposed inside the shield portion 32, and by the thrust of the shield jack 35 based on the segment 10 assembled inside the shield portion 32 and disposed in the natural ground G. The shield machine 30 moves forward.
Further, an injection hole 34 for filling the tunnel gap filler 12 into the gap K3 is passed through the upper portion of the shield portion 32. Note that the shape, number, arrangement, and the like of the injection hole 34 are not limited, and are appropriately formed so as to be able to reliably fill the gap K3.

  The segment 10 according to the first embodiment is formed in a circular cross section having an outer diameter slightly smaller than the outer diameter of the shield portion 32 by assembling the members divided into a predetermined number inside the shield machine 30. Has been. The configuration, material, shape, and the like of the segment 10 are not limited to those described above, and are appropriately set in consideration of the situation at the site, the completed cross section of the tunnel T, and the like. In addition, the code | symbol 35 in FIG. 1 is a tail seal for preventing inflow of earth and sand etc. to the inside of the shield machine 30. FIG.

An injection pipe (pipe) 21 for feeding the tunnel gap filler 12 through the mixing portion 22 is attached to the injection hole 34.
As shown in FIG. 2, the injection pipe 21 includes a first injection pipe 21 a that sends a monovalent or divalent metal salt aqueous solution of acrylic acid, and a second injection pipe 21 b that sends an aqueous solution of an aluminum water-soluble salt. And three of the third injection pipes 21c for feeding a bisulfite aqueous solution. Each injection tube 21 is connected via an injector 23 to a first tank 24a storing a monovalent or divalent metal salt aqueous solution of acrylic acid and a second tank storing an aqueous solution of aluminum water-soluble salt. The tank 24b is connected to a third tank 24c in which an aqueous bisulfite solution is stored.

As shown in FIG. 1, the tunnel T is constructed by connecting the segment 10 formed in a predetermined shape inside the shield machine 30 to the ground G at any time and using the ground head G by the cutter head 31 of the shield machine 30. It is carried out by excavating by the thrust of the shield jack 35 while excavating (excavation process).
At this time, since the excavation surface K2 formed by the cutter head 31 of the shield machine 30 is formed larger than the outer shape of the shield part 32, the cutter head 31 is located behind the excavation surface K2 and the shield part 32. A gap K3 is formed.

  For this reason, for the purpose of preventing the collapse of the natural ground G, the tunnel gap filler 12 is filled from the injection hole 34 formed in the shield portion 32 as needed (filling step). Furthermore, since the segment 10 is formed inside the shield machine 30 and has an outer diameter slightly smaller than the outer diameter of the shield part 32, there is no gap between the tunnel gap filler 12 and the segment 10. Is formed. For this reason, backfilling with the backfilling material 11 is performed on the back surface of the segment 10 at any time as the shield machine 30 is dug. Here, in the first embodiment, a cement-based filler that solidifies integrally with the segment 10 is used as the backfill material 11. In addition, as the material of the backfill material 11, for example, a tunnel gap filler 12 may be used, as long as it suppresses the collapse of the natural ground G by exhibiting a predetermined strength and is excellent in water-stopping property. It is not limited to cement fillers.

  When the shield machine 30 reaches a reach position (not shown), the back face of the tunnel lining (segment 10) is backed by the backfill material 11 and the tunnel gap filler 12 by unloading the shield machine 30 from the reach position. Construction of the filled tunnel T is completed.

  In addition, the filler 12 for the tunnel gap is made of a monovalent or divalent metal salt aqueous solution of acrylic acid by three injection pipes 21 extending from an appropriate place on the ground or in the mine to the inside of the shield machine 30. The aqueous solution of the aluminum water-soluble salt and the aqueous bisulfite solution are individually fed and mixed by the mixing unit 22 immediately before filling the gap K3 (see FIG. 2). Hereinafter, when “a monovalent or divalent metal salt aqueous solution of acrylic acid, an aqueous solution of an aluminum water-soluble salt and an aqueous bisulfite solution” are not distinguished, they may be simply referred to as “aqueous solution”.

  As shown in FIG. 2, the tunnel gap filler 12 is a first tank in which each aqueous solution constituting the tunnel gap filler 12 is installed in an injection plant disposed at an appropriate place on the ground or in a mine. 24a, the second tank 24b, and the third tank 24c are individually stored. Each of the three types of aqueous solutions is adjusted to a predetermined flow rate by the injector 23, and is then passed through the first injection tube 21a, the second injection tube 21b, and the third injection tube 21c, respectively. The liquid is sent to the inside.

  As shown in FIG. 1, each aqueous solution sent to the inside of the shield machine 30 is mixed by the mixing unit 22 fixed to the injection hole 34 and then discharged from the injection hole 34 to the gap K3. The injection hole 34 is arranged on the upper surface of the shield machine 30 and the tunnel gap filler 12 is injected upward into the gap K3. The entire circumference of 30 is filled. In addition to the injection hole 34, a confirmation hole (not shown) is formed in the shield machine 30, and the filling state of the tunnel gap filler 12 is confirmed using this confirmation hole. The confirmation of the filling state of the tunnel gap filling material 12 is not limited to the above method, and an appropriate method is appropriately selected, such as by performing a hitting sound investigation of hitting the inner surface of the shield machine 30 with a hammer or the like. Just do it. Also, the injection hole 34 is increased as appropriate according to the size of the shield machine (tunnel excavator) 30.

  Further, when the excavation work is interrupted for some reason, the gap K4 between the face K1 and the cutter head 31 is also filled with the tunnel gap filler 12 to prevent the face K1 from collapsing. .

  As described above, according to the tunnel gap filler and the tunnel excavation method using the same according to the first embodiment, the following effects can be obtained.

  That is, in the first embodiment, as the tunnel void filler 12, an acrylic mixture comprising a monovalent or divalent metal salt aqueous solution of acrylic acid, an aqueous solution of an aluminum water-soluble salt, and a bisulfite aqueous solution is used. Since it is used, it has a property of weak adhesion to iron, and even if it is filled and solidified in the gap K3 between the excavation surface K2 and the shield machine 30, it will adhere to the shield machine 30 and so on. Will not interfere with the excavation of. Therefore, tunnel construction that is safe and excellent in workability in which collapse of the natural ground G is suppressed is possible. Further, even when the excavation work is interrupted for some reason, it is possible to prevent the face K1 from collapsing by filling the gap K4 between the face K1 and the cutter head 31 with the tunnel gap filler 12. Become. In addition, even after the construction is resumed, the tunnel gap filler 12 is hardened to a predetermined strength, so that excavation is possible, and earth and sand containing the tunnel gap filler 12 may adhere in the chamber 33. Therefore, the construction can be performed smoothly. When the excavation operation is interrupted, the tunnel gap filler 12 may be filled into the chamber 33 together with the filling of the gap gap filler 12 into the gap K4.

  Moreover, since the filler 12 for tunnel gaps is hardened to a predetermined strength at an early stage after mixing each aqueous solution, it also has a function of suppressing the collapse of the natural ground G and can be used as a backfill material as it is. it can. Therefore, the backfill material 11 to be filled in the back surface of the segment 10 may be filled only in the gap between the tunnel gap 12 and the segment 10, and the conventional method of performing backfill injection into the gap between the excavation surface K <b> 2 and the segment 10. Compared to, the amount can be greatly reduced.

  In addition, since the filler 12 for the tunnel gap can be adjusted so that it hardens at an early stage, the filler that penetrates into the ground (tunnel gap) even in constructions with relatively large gaps such as sand layers and gravel-mixed soil layers. The amount of the filler 12) for use is small, and the gap K3 can be reliably filled while minimizing the amount of filler, which is economical. Moreover, since it becomes possible to minimize the amount of the filler 12 for the tunnel gap and the backfilling material 11 required, the area of the stock yard necessary for the storage can be reduced, such as an urban area. Also, it can be suitably applied to construction sites where there are restrictions on the site.

Moreover, quality control of each aqueous solution is easy because it is only stored in the individual tanks 24a, 24b, and 24c. In addition, since the quality after injection into the gap K3 has little variation, the reliability is high.
Further, since the tunnel gap filler 12 according to the present invention has a low viscosity, after filling into the gap K3, it flows down into the entire gap K3 and is reliably filled, so that high-quality tunnel construction is possible.

  Moreover, since the filling material 12 for tunnel gaps of this invention can adjust hardening time and the intensity | strength after hardening by the mixing | blending of each aqueous solution, the applicable geology is not limited.

<Second Embodiment>
Hereinafter, a second embodiment (hereinafter may be simply referred to as “second embodiment”) will be described.
FIG. 3 is a cross-sectional view showing a state of filling a gap between a tunnel boring machine (hereinafter sometimes referred to as “TBM”) which is a tunnel excavator for tunnel gap filler according to the second embodiment and a natural ground. .

  In the second embodiment, as shown in FIG. 3, the tunnel is formed by the steel support 13 assembled behind the TBM 40 and the shotcrete 14 sprayed on the ground G while excavating the ground (rock) G by the TBM 40. In the TBM construction method for constructing T, the tunnel gap filler 12 made of an acrylic material is filled into the gap K3 formed between the periphery of the TBM 40 and the excavation surface K2 of the natural ground G as the tunnel is dug. In the second embodiment, the open type TBM 40 is used as a tunnel excavator. However, for example, a rock shield or a full shield type TBM may be applied, and a main gripper and a shield part are provided. The tunnel excavator is not limited. Moreover, in 2nd Embodiment, it was set as the structure which supports a natural ground by the steel support work 13 and shotcrete 14, However For example, a liner, a segment, etc. may be used and the support structure of a natural ground is limited. It is not a thing. Here, when a liner or a segment is used as a support, the back of the liner or segment is filled with a backfill material.

  As each aqueous solution of the tunnel gap filler 12 according to the second embodiment, the same solution as that used in the first embodiment is used, and detailed description thereof is omitted.

  As shown in FIG. 3, the TBM 40 includes a cutter head 41 in which a plurality of roller cutters 41 a that mainly excavate natural ground G are disposed, and various facilities inside the TBM 40 that are located behind the cutter head 41. And a main gripper 46 supported by the main beam 47 and projecting laterally behind the shield part 42 to take a digging reaction force from the rock mass (natural ground G). The TBM 40 according to the second embodiment is formed in a circular cross section, and the outer diameter of the shield portion 42 is slightly smaller than the inner diameter of the excavation surface K2 formed by the cutter head 41. The shape of the TBM 40 is not limited to a circular cross section. For example, the TBM 40 has a rectangular cross section, an elliptical cross section, a double cross section with a plurality of circular cross sections connected, or a triple cross section. May be used.

A chamber 43 in which the earth and sand excavated by the cutter head 41 is temporarily deposited is formed on the back surface of the cutter head 41 inside the shield part 42. The earth and sand in the chamber 43 is tunneled by an earth and sand conveying means (not shown). Transported outside of T. The TBM 40 excavates the face K1 by applying a reaction force to the surrounding rock mass (excavation surface K2) by the main gripper 46.
In addition, an injection hole 44 for filling the tunnel gap filler 12 into the gap K3 is penetrated in the upper part of the shield part. Note that the shape, number, arrangement, and the like of the injection hole 44 are not limited, and are appropriately formed so that the gap K3 can be reliably filled. In addition, the code | symbol 45 in FIG. 3 is an auxiliary | assistant gripper which corrects the direction of excavation of TBM40.

The steel support 13 is configured by arranging a steel mold formed in advance according to a tunnel cross-sectional shape along the excavation surface K2 of the natural ground. And the shotcrete 14 is sprayed by the predetermined thickness to the excavation surface K2 in which the steel supporter 13 is arrange | positioned.
Here, the injection device 20 for the tunnel gap filling material 12 is the same as that shown in the first embodiment, and thus detailed description thereof is omitted. In addition, in 2nd Embodiment, the injection apparatus 20 shall be arrange | positioned in a mine as an injection | pouring plant which can be installed in the predetermined position in a work yard near the origin side wellhead which is not illustrated, or a mine.

As shown in FIG. 3, the tunnel T according to the second embodiment is constructed by the main gripper 46 while assembling the steel support 13 and spraying the sprayed concrete 14 onto the ground G at the rear of the TBM 40. It is performed by excavating the natural ground G with the cutter head 41 while taking the excavation reaction force (excavation process).
At this time, the excavation surface K <b> 2 formed by the cutter head 41 of the TBM 40 is formed larger than the outer shape of the shield part 42, so that a gap K <b> 3 is formed behind the cutter head 41.

For this reason, for the purpose of preventing the collapse of the natural ground G, the tunnel gap filler 12 is filled from time to time through the injection hole 44 formed in the shield part 42 (filling step).
Then, after the TBM 40 is assembled, the steel support 13 divided and carried into the mine as needed is assembled along the cross section of the excavation surface K2, and then the shotcrete 14 is sprayed.

  Completion of the excavation by the TBM 40 completes the construction of the tunnel T having a tunnel support or lining composed of the steel support 13, the shotcrete 14, and the tunnel gap filler 12.

  In addition, since the filling method to the space | gap K3 of the filler 12 for tunnel space | gap is the same as the method shown in 1st Embodiment, detailed description is abbreviate | omitted.

  When the excavation operation is interrupted for some reason, the gap K4 between the face K1 and the cutter head 41 is also filled with the tunnel gap filler 12 to prevent the face K1 from collapsing. .

  As described above, according to the tunnel gap filling material and the tunnel excavation method using the same according to the second embodiment, the collapse of the natural ground G is suppressed even in the tunnel construction in the collapsible rock such as the rock with many cracks. It is possible to safely perform tunnel construction by the TBM method.

  That is, in the second embodiment, as the tunnel void filler 12, an acrylic mixture comprising a monovalent or divalent metal salt aqueous solution of acrylic acid, an aqueous solution of aluminum water-soluble salt, and a bisulfite aqueous solution is used. Because it is used, it has a property of weak adhesion to iron, and even if it is filled in the gap K3 between the excavation surface K2 and the TBM 40 and solidifies, it adheres to the TBM 40 and prevents the tunnel T from being dug. There is no. Therefore, the collapse of the natural ground G is suppressed, and tunnel construction that is safe and excellent in workability is possible. Even when the excavation work is interrupted for some reason, it is possible to prevent the face K1 from collapsing by filling the gap K4 between the face K1 and the cutter head 41 with the tunnel gap filler 12. It becomes. In addition, since the earth and sand containing the tunnel gap filler 12 does not adhere in the chamber 43 even after the construction is resumed, the construction can be performed smoothly. When the excavation work is interrupted, the tunnel gap filler 12 may be filled in the chamber 43 together with the filling of the gap gap filler 12 into the gap K4.

  The operational effects of the tunnel gap filling material and the tunnel excavation method using the same according to the second embodiment are the same as those shown in the first embodiment, and thus detailed description thereof is omitted.

As mentioned above, although preferred embodiment was described about this invention, this invention is not limited to the said embodiment, A design change is possible suitably in the range which does not deviate from the meaning of this invention.
For example, in the first embodiment, the tunnel gap filler filled in the gap formed between the shield machine and the excavation surface and the backfilling material filled in the back surface of the segment are made of different materials. However, the present invention is not limited to this, and the tunnel void filler of the present invention may be used as a segment back-filling material.

Moreover, in each said embodiment, it was set as the structure which fixes a mixing part to the injection hole formed in the excavator, and mixes aqueous solution just before injection | pouring to a space | gap, but the timing which mixes each aqueous solution is limited. Instead, for example, if the extension of the tunnel is short and the backfill material does not harden in the middle of the liquid feeding in the injection pipe, a premixed liquid may be fed to fill the gap.
Further, instead of mixing three types of aqueous solutions at a time, after mixing two types of aqueous solutions, another type of aqueous solution may be added and mixed.

It is sectional drawing which shows the filling condition to the space | gap of the shield machine of the tunnel space | gap filler which concerns on 1st Embodiment, and a natural ground. It is the schematic which shows the injection apparatus of the filler for tunnel gaps concerning 1st Embodiment. It is sectional drawing which shows the filling condition to the space | gap of the tunnel boring machine and the natural ground of the filler for tunnel space | gap which concerns on 2nd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Segment 11 Backfilling material 12 Tunnel gap filling material 13 Steel support 14 Shotcrete 20 Injection device 21 Injection pipe 22 Mixing part 30 Shielding machine 40 TBM (tunnel boring machine)
G Ground mountain K1 Face face K2 Excavation face K3, K4 Air gap

Claims (6)

A tunnel gap filling material filled in a gap formed between a surrounding area of a tunnel excavator and a natural ground,
The filler for tunnel voids is formed by mixing a monovalent or divalent metal salt aqueous solution of acrylic acid, an aqueous solution of an aluminum water-soluble salt, and a bisulfite aqueous solution. .   The aqueous metal salt solution is mixed at a ratio of 0.9 to 1.5 and the aqueous bisulfite solution is 0.9 to 1.5 with respect to 1. The filler for tunnel voids according to claim 1, characterized in that it is characterized in that Excavation process to excavate natural ground with a tunnel excavator;
A tunnel excavation method comprising: filling a gap formed between the tunnel excavator and the ground with a tunnel gap filler made of an acrylic material in accordance with the excavation process.   The filling step includes a step of mixing the monovalent or divalent metal salt aqueous solution of acrylic acid, the aqueous solution of aluminum water-soluble salt, and the bisulfite aqueous solution to form the tunnel void filler. The tunnel excavation method according to claim 3, wherein:   When the aqueous solution of the metal salt is mixed with the aqueous solution of the aluminum water-soluble salt in a ratio of 0.9 to 1.5 and the aqueous bisulfite solution is mixed in a ratio of 0.9 to 1.5. The tunnel excavation method according to claim 4, wherein the gap filling material is constituted. A step of individually feeding the aqueous solution of the monovalent or divalent metal salt of the acrylic acid, the aqueous solution of the aluminum water salt, and the aqueous solution of the bisulfite with the three filling lines in the filling step; ,
A step of mixing the filled monovalent or divalent metal salt aqueous solution of the acrylic acid, the aqueous solution of the aluminum water salt, and the aqueous bisulfite solution to fill the voids. The tunnel excavation method according to claim 4 or 5.

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