JPH11200786A - Sealing material for tail, etc., and sealing raw material and shield tunneling method and injection system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sealing material for a tail, etc., which is safety and by which work environment is not deteriorated. SOLUTION: The sealing material is injected among tail brushes 6 moved along the outer circumferential surface of a segment 4 assembled at the rear section of a shield machine 1 and into an entrance space at the time of the departure of the shield machine 1. A sealing raw material containing a 1-15 wt.% alkali irritant consisting of at least one kind selected from a substance obtained by hydrating, re-grinding and drying at least 1-30 wt.% one kind selected from a 55-98 wt.% silicate mineral comprising not less than 50 wt.% montmorillonite, a water-soluble high-molecular thickening agent, sepiolite and attapulgite, sodium hydroxide, magnesium oxide, calcium hydroxide and cement and fly ash is mixed with water at a rate as the sealing raw material/(the sealing raw material + water) = 0.1-0.3 at a weight ratio.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sealing material such as a tail used in a shielding method, and further relates to a shielding method using the sealing material and a sealing material injection system.

[0002]

2. Description of the Related Art The shield method is a method of excavating the ground with an excavator called a shield machine, assembling a segment behind the shield machine, and constructing a tunnel in the ground while using this as a reaction force. In this shield method, a gap (tail void) occurs due to the difference between the outer diameter of the segment assembled at the rear of the shield machine and the outer diameter of the excavation of the shield machine. In order to prevent the backing material filling the tail void, groundwater, drilling mud, drilling additives, etc. from entering the shield machine through this gap, several rows of wire brushes are arranged in a ring on the inner periphery of the skin plate in the shield machine. There is provided a seal structure called a tail brush having a structure for mounting and pressing the brush against the segment side. Further, grease mainly composed of oil and fat is injected between the several rows of tail brushes to seal the tail portion. In addition, inventions relating to compositions have been found, but those in which an inorganic material is partially blended mainly with fats and oils (JP-A-2-96087) and those in which bentonite is blended with organic polymers and fibers (JP-A-9-125881)
No.), and conventional sealing materials are all based on organic materials.

[0003]

As described above, the sealing material used in the conventional shield method is grease mainly composed of oils and fats, but there is a danger of accidents due to fire. Or fire in storage area. In addition, adhesion to clothing or to a scaffold causes a fall accident, which is a factor of deteriorating the working environment. Also, if grease flows out into the ground, oil and fat components may contaminate groundwater. Further, the grease does not have high flowability, it is difficult to inject the grease into the space between the tail brushes, the injection pressure is high, the injection pipe must be thick, and it is necessary to provide many injection points. And since grease is expensive, when a tail brush wears out, loss is large and it is uneconomical.

An object of the present invention is to provide a sealing material such as a tail made of an inorganic material which is safe and does not deteriorate the working environment, and further provide a shielding method using the sealing material and a sealing material injection system. Is to do.

[0005]

In order to achieve this object, according to the first aspect of the present invention, there is provided a space between a tail brush moving along an outer peripheral surface of a segment assembled at a rear portion of a shield machine and a shield machine. A sealing material injected into the entrance space at the time of start of the vehicle, comprising 55 to 98 silicate minerals containing 50% by weight or more of montmorillonite.
1% by weight of at least one selected from the group consisting of water-soluble polymer thickeners, sepiolite and attapulgite.
30% by weight, containing 1 to 15% by weight of an alkali stimulant consisting of at least one selected from sodium hydroxide, magnesium oxide, calcium hydroxide, hydrated cement, reground and dried, and fly ash Seal material to be used, the weight ratio of seal material / (seal material +
(Water) = sealing material such as tail mixed with water at a ratio of 0.1 to 0.3.

In the sealing material according to the first aspect, the silicate mineral contains montmorillonite in an amount of 50% by weight or more. Generally, bentonite is represented as a silicate mineral containing montmorillonite. Bentonite has higher quality as the swelling power is larger. In the sealing material of the first aspect, a silicate mineral having a swelling power of 30 cc / 2 g or more after one day is used. The swelling force is determined by the standard test method of the Bentonite Industry Association of Japan. That is, in the sealing material of the first aspect, the silicate mineral containing montmorillonite at 50% by weight or more refers to, for example, high-grade bentonite having a swelling power of 30 cc / 2g or more after one day.

[0007] As described in claim 2, the water-soluble polymer-based thickener is carboxymethyl cellulose (CM).
C), at least one selected from water-soluble cellulose ethers such as methylcellulose (MC), natural gums and artificial gums. If the viscosity of the sealing material is low, it is advisable to add gum (natural gum or artificial gum). When both the cellulose ether and the gum are contained, the sealing material preferably contains 1 to 20% by weight of the cellulose ether and 10% by weight or less of the gum. Further, only gum may be contained instead of cellulose ether.

Attapulgite and sepiolite are minerals. The thickening effect can also be increased by replacing these with cellulose ether or gum, or adding them together with cellulose ether or gum. Also,
Attapulgite and sepiolite have the property of suspending and thickening even in seawater, so it is better to contain them depending on the ground conditions.

The alkali stimulant has the effect of significantly improving the viscous effect of the material.

[0010] Since the sealing material of the first aspect does not contain oils and fats, there is no danger of fire or the like, and since it is water-based and can be easily washed off with water, it contributes to improvement of the working environment.

The sealing material according to the first aspect may further include an anionic coagulant in the sealing material of 5% by weight or less, as described in the third aspect. By containing an anionic coagulant, the sealing material can be made slimy, and the piping resistance when pouring between the tail brushes can be reduced. Further, as described in claim 4, the fiber may further contain short fibers of at least one kind selected from vinylon, polypropylene, acrylic and cotton and having a length of 10 mm or less. The short fibers integrate the sealing material and prevent the sealing material from separating due to the influence of groundwater, backfill material, drilling mud, drilling additives, grout material, etc., which penetrate into the tail void. Further, as described in claim 5, a rust preventive material may be further contained. Rust prevention materials are used to prevent oxidation of shield machines and tail brushes.

According to a sixth aspect of the present invention, there is provided a seal which is injected into the entrance space between the tail brushes moving along the outer peripheral surface of the segment assembled at the rear part of the shield machine and the entrance space when the shield machine is started in a state of being mixed with water. 55 to 98% by weight of a silicate mineral containing 50% by weight or more of montmorillonite, 1 to 30% by weight of at least one selected from a water-soluble polymeric thickener, sepiolite and attapulgite, A seal material containing 1 to 15% by weight of an alkali stimulant consisting of at least one selected from sodium oxide, magnesium oxide, calcium hydroxide, cement hydrated, reground and dried, and fly ash. .

According to a seventh aspect of the present invention, a sealing material such as a tail according to any one of the first, second, third, fourth and fifth aspects is provided on an outer peripheral surface of a segment assembled at a rear portion of a shield machine. This is a shield method characterized in that the tail portion is sealed by injecting between tail brushes moving along. By using an aqueous sealing material in this way, it is possible to perform a shielding method that is safe and does not deteriorate the working environment.

In the shield method according to the seventh aspect, as described in the eighth aspect, immediately before the sealing material is injected between the tail brushes, the sealing material containing no alkali stimulant is used.
It is preferable to mix the solution B and the solution B containing the alkali stimulant. Then, the liquid can be sent in a low-viscosity state immediately before the injection between the tail brushes, and the injection work from a distance can be performed without increasing the injection pressure of the pump. Further, since the injection pressure is low, it is not necessary to use a plunger type (piston type) pump used for injecting the conventional grease. As described in claim 9, the liquid A comprises a silicate mineral containing 50% by weight or more of montmorillonite and at least one selected from a water-soluble polymer-based thickener, sepiolite, and attapulgite. Blended at a weight ratio of 1000: 0-100,
The liquid B was prepared at a weight concentration of 10 to 30% with respect to water, and the liquid B contained 10% or more of silicate mineral containing montmorillonite at 50% by weight or more based on the weight ratio of water to 1000.
At least one selected from water-soluble polymer-based thickeners, sepiolite and attapulgite.
-10, sodium hydroxide, magnesium oxide, calcium hydroxide, hydrated cement, re-crushed and dried, and fly ash selected from alkali stimulants of at least one selected from the group consisting of 10-100. It is preferable that the mixing ratio of the liquid A and the liquid B at the time of forming the sealing material is 1000: 50 to 300 in terms of volume ratio.

The invention of claim 10 is the first invention.
A tank for storing a sealing material such as a tail described in any one of 2, 3, 4, and 5, and a tail brush for moving the sealing material in the tank along an outer peripheral surface of a segment assembled at a rear portion of the shield machine. An injection circuit for injecting between,
A pump for pumping the sealing material, a sensor for detecting the injection pressure of the sealing material, and the pump is stopped when the injection pressure of the sealing material exceeds the reference value, and the injection pressure of the sealing material does not reach the reference value. An injection system comprising a control unit that sometimes activates the pump. In the injection system according to the tenth aspect, as described in the eleventh aspect, the sensor can be arranged, for example, in the middle of an injection circuit.

[0016]

Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an explanatory diagram of the shield machine 1. A cutter 2 is provided at the tip of the shield machine 1 (the left end in FIG. 1). The cutter 2 rotates to excavate the ground 3 and move forward, while being behind the shield machine 1 (to the right in FIG. 1). Assemble the segment 4 into a cylindrical shape to build a shield. On the inner periphery of the cylindrical skin plate 5 covering the outer periphery of the shield machine 1, tail brushes 6 arranged in a ring shape in three rows in the illustrated example are provided at appropriate intervals. By pressing the tail brush 6 to the outside of the segment 4, the tail brush 6 moves along the outer peripheral surface of the segment 4 as the shield machine 1 advances. The tail brush 6 is composed of, for example, a metal wire brush, or a metal wire brush in which the surroundings and gaps are covered with urethane foam. A sealing material 7 is injected through an injection circuit 8 between the tail brushes 6 arranged in these three rows. Further, the tip side of the injection circuit 8 is branched into several lines (five in the illustrated example) so that the sealing material 7 can be injected between the tail brushes 6 at a plurality of locations.

As shown in an enlarged view in FIG. 2, a tank T storing a sealing material 7 is arranged at the most upstream side of the injection circuit 8, and the sealing material 7 in the tank T is injected by the operation of the pump P. The liquid is sent through the circuit 8, and the sealing material 7 is injected between the tail brushes 6 in the gap between the outer peripheral surface of the segment 4 and the inner peripheral surface of the skin plate 5. Then, by the sealing structure composed of the tail brushes 6 and the sealing material 7 injected therebetween, the backing material 9 filled in the tail voids on the outer peripheral surface of the segment 4 assembled behind the shielding machine 1, Groundwater, drilling mud, drilling additives, and the like are prevented from entering the shield machine 1.

Here, the sealing material 7 used in the present invention is an aqueous material made by mixing the sealing materials shown in Table 1 with water, and is a conventional oil-based material such as grease. Unlike sealing materials, it has non-oil properties. The mixing ratio between the sealing material and water is preferably a ratio of sealing material / (sealing material + water) = 0.1 to 0.3 by weight.

[0019]

[Table 1]

The silicate mineral of compounding material a shown in Table 1 contains at least 50% by weight of montmorillonite and has a swelling power of 30 cc / 2 g or more after one day. For example,
High-grade bentonite having a swelling power of 30 cc / 2 g or more after one day may be used. Cellulose ethers such as carboxymethylcellulose (CMC) and methylcellulose (MC), attapulgite,
Sepiolite uses any of them or a combination thereof. By adding the compound material b, the effect of increasing the viscosity of the sealing material 7 can be increased. Attapulgite and sepiolite can maintain viscosity even in seawater. As the alkali stimulant shown in the compounding material c, any of sodium hydroxide, magnesium oxide, calcium hydroxide, hydrated cement, re-crushed and dried, fly ash, or a combination thereof is used. This alkali stimulant has the effect of significantly improving the viscous effect of the sealing material 7. The sealing material 7 used in the present invention may contain an anionic coagulant shown in the compounding material d in addition to the compounding materials a to c. Alternatively, they may contain a combination thereof. By containing an anionic coagulant, the sealing material 7 is slimy,
Piping resistance during injection between the tail brushes 6 can be reduced. In addition, by containing a natural gum or an artificial gum, a thickening effect of the sealing material 7 can be obtained. Table 1
Although not shown, the sealing material 7 used in the present invention is not shown.
May contain a short fiber or a rust preventive material. The short fiber is made of vinylon, polypropylene, acrylic, cotton, or the like and has a length of 10 mm or less, and integrates the sealing material 7. The rust preventive has an effect of preventing oxidation of the shield machine 1 and the tail brush 6. Since the sealing material 7 used in the present invention is a non-oil containing no oil, there is no danger of fire or the like, and it is water-based and can be easily washed off with water.

Here, as a method of injecting the sealing material 7 between the tail brushes 6, there is a method of not containing an alkali stimulant.
It is also conceivable to mix the liquid and the B liquid containing the alkali stimulant before injection to form a sealing material, and to inject the sealing material 7 between the tail brushes 6. That is, in the embodiment shown in FIG. 3, the upstream side of the injection circuit 8 is connected to the first injection circuit 8a and the second injection circuit 8a.
Of the first injection circuit 8a and the second injection circuit 8b.
And a tank Tb. Then, a liquid A containing no alkali stimulant is stored in the tank Ta, and a liquid B containing an alkali stimulant is stored in one tank Tb. The liquid A stored in the tank Ta is composed of a silicate mineral containing 50% by weight or more of montmorillonite and at least one selected from a water-soluble polymer-based thickener, sepiolite, and attapulgite at a ratio of 1000: 0 to 100. And a solution prepared at a weight concentration of 10 to 30% with respect to water. The liquid B stored in the tank Tb is water 100
10 to 100% by weight of a silicate mineral containing 50% by weight or more of montmorillonite, and 1 to 10% by weight of at least one selected from a water-soluble polymer-based thickener, sepiolite and attapulgite in a weight ratio to 0. , Sodium hydroxide, magnesium oxide, calcium hydroxide,
It is preferable that the liquid be prepared by blending at least 10% by weight of at least one alkali stimulant selected from hydrated cement, crushed and dried, and fly ash. Then, the liquid A in the tank Ta is sent through the injection circuit 8a by operating the pump Pa, and the liquid B in the tank Tb is sent through the injection circuit 8b by operating the pump Pb. The liquid A and the liquid B are mixed, and the sealing material 7 created just before is injected between the tail brushes 6. By separately feeding the liquid A and the liquid B in this manner, the sealing material 7 can be transported in a low-viscosity state immediately before the liquid is injected between the tail brushes 6 without increasing the injection pressure of the pump Pa or the pump Pb. Injection work from a distance is also possible, and it is not necessary to use a plunger type (piston type) pump. For example, by controlling the operation amount of the pump Pa or the pump Pb, the mixing ratio of the liquid A and the liquid B at the time of forming the sealing material 7 is changed by the volume ratio of the liquid A:
It is preferable to adjust so that B solution = 1000: 50-300.

Next, FIG. 4 is an explanatory view schematically showing an injection system 10 configured to automatically inject the sealing material 7 stored in the tank T described above with reference to FIG. is there. In the injection system 10, a sensor S is disposed in the middle of the injection circuit 8, and the injection pressure of the sealing material 7 detected by the sensor S is input to the control unit 11. The control unit 11 controls the transmission 12 of the pump P for pumping the sealing material 7 between the tail brushes 6 via the injection circuit 8 and controls the opening and closing operation of the valve 13 arranged in the middle of the injection circuit 8. It is supposed to. Further, in the injection system 10, the storage amount of the sealing material 7 in the tank T is detected by the liquid level sensor 14, and when the remaining amount of the sealing material 7 becomes small, the operation of the pump P 'causes the tank T to operate. It is configured to supply the sealing material 7 therein.

When the injection pressure of the sealing material 7 detected by the sensor S becomes equal to or higher than the reference value, the controller 1
The operation of the pump P is stopped by the signal from 1, the valve 13 is closed, and the injection of the sealing material 7 is stopped. On the other hand, when the injection pressure of the sealing material 7 detected by the sensor S has not reached the reference value, the pump P is operated by the signal from the control unit 11, the valve 13 is opened, and the injection of the sealing material 7 is started. . When the rate of increase of the injection pressure of the sealing material 7 detected by the sensor S is low, the operation amount of the transmission 12 can be increased to increase the liquid supply amount. When the liquid level sensor 14 detects that the storage amount of the sealing material 7 in the tank T has decreased, the pump P 'is operated to supply the sealing material 7 into the tank T. The use of such an injection system 10 makes it possible to automate the injection of the sealing material 7 between the tail brushes 6 and to continuously inject the sealing material 7 into the space between the tail brushes 6.
Since the sealing material 7 can be injected in between, it is possible to improve the water stoppage, the leakage of water, and the sealing property against the grout material.

Next, FIGS. 5 to 8 show the state when the shield machine 1 starts moving. When the shield machine 1 starts, first, as shown in FIG.
A starting port 21 is formed at 0, and a packing 22 is attached around the starting port 21. Then, as shown in FIG.
The excavation is started by inserting the tip (the right end in FIGS. 5 to 8) of the shield machine 1 provided with the gasket into the face through the packing 22, and the assembly of the segment 4 is started behind the shield machine 1. Then, as shown in FIG. 7, when the tail portion of the shield machine 1 (the left end of the shield machine 1 in FIGS. 5 to 8) just enters the ground 3, the tail portion is formed around the segment 4 at the entrance of the tunnel. Entrance space 2
By injecting the sealing material 24 into 3, the groundwater, drilling muddy water, drilling additives, etc. are prevented from leaking to the outside. Thus, the entrance space 23 is sealed with the sealing material 24.
8, the shield machine 1 is further advanced to continue excavation, and the tail void formed around the segment 4 is filled with the backing material 25.

As described above, the sealing material 24 injected into the entrance space 23 when the shield machine 1 starts moving is the same as the sealing material 7 injected between the tail brushes 6 of the shield machine 1 described above. May be. Then, by using the water-based sealing material 24, it is possible to similarly enjoy the effects of avoiding the danger of fire and the like and improving the working environment. When the sealing material 24 is injected into the entrance space 23 as described above, the grout hole 25 of the segment 4 located inside the vicinity of the packing 22 can be used as shown in FIG. Further, the pressure of the sealing material 24 in the injection circuit 26 connected to the grout hole 25 ′ is detected by the pressure gauge 27, and the pressure of the sealing material 24 injected into the entrance space 23 is detected by the pressure gauge 28. It is also conceivable to configure a system for automatically injecting the sealing material 24 into the entrance space 23.

[0026]

EXAMPLES Next, examples were performed on the sealing material according to the present invention. First, the improvement of viscosity by an alkali stimulus was examined. Table 2 shows the results.

[0027]

[Table 2]

Material a is 50% by weight of montmorillonite.
It is a high quality bentonite including the above. No which is a comparative example
As shown in FIG. 1, even when a high-grade bentonite having a high montmorillonite content is simply used, the viscosity does not easily increase. In order to obtain a high viscosity, the content of high-grade bentonite must be increased, so that the density (raw specific gravity) increases. For this reason, the operability is deteriorated, for example, the pipe resistance of pumping during injection is increased. On the other hand, Nos. 2 and 4 according to the embodiment of the present invention
As shown in (1), a significant increase in viscosity can be obtained by adding magnesium oxide as an alkali stimulant. In this case, the piping resistance for pumping is low,
Cost reduction when transporting products. In addition, as shown in Comparative Example No. 3, the addition of the CMC results in a lower viscosity increase than the case where the alkali stimulant (magnesium oxide) is added.

Next, a simple vane test was performed on the sealing material of each composition, and the change in shearing force was examined. Table 3 shows the composition of each sealing material. The kneading concentration in the table indicates the weight concentration of the sealing material with respect to the total weight of the sealing material (water + sealing material). Nos. 4, 5, and 6 in Table 3 are examples of the present invention,
1, 2, and 3 show comparative examples. FIG. 1 is a graph comparing the change over time of the shearing force obtained from the simple vane test for each sealing material shown in Table 3 with respect to each compound.
0. From FIG. 10, it can be understood that the sealing material in the range of the present invention has a larger shearing force than the comparative example. When the shearing force is large, the viscosity of the sealing material increases in proportion to the sealing material, and when the sealing material is filled between the tail brushes or the like, the adhesive force with the brushes increases, and it becomes difficult to separate due to external force (water pressure or the like). In addition, the sealing material itself is also integrated, thereby increasing the separation resistance.

[0030]

[Table 3]

Next, the change in strength due to the impact during the injection of the pump was examined. SC (montmorillonite-containing silicate mineral):
A sealing material blended with Mg0 (magnesium oxide): BSP (a water-soluble polymer containing CMC) = 940: 30: 30 was kneaded with water at a weight concentration of 14%, and the fiber was mixed with 0.5% of water.
% Was added to prepare a sealing material. An impact was applied to the sealing material three days after kneading, and the resurrection state (recovery state) of the shearing force was examined. The result is shown in FIG. From the test results, it was confirmed that the pressure and pressure of the sealant of the present invention reduced the viscosity and shear force that would cause resistance during pipe transportation by pressurization, and that the fluidity could be improved by the pump pressure during injection. . It was also found that the shearing force was restored after injection, and the viscosity increased. The filling property was good, and the strength after injection increased, which could reduce the outflow of the tail seal to the outside (ground side). is there.
Furthermore, by utilizing this characteristic, it is possible to maintain the pressure between the tail brushes, transmit the pressure, and maintain the pressure, thereby facilitating automatic injection.

Next, a method for producing a sealing material by mixing the solution A containing no alkali stimulant and the solution B containing the alkali stimulus immediately before injection was examined. Table 4 shows the composition of each solution A and solution B. The test was performed with the mixing ratio of the A liquid and the B liquid being A: B = 1000: 100 by volume ratio. FIG. 12 shows the change in strength of the sealing material immediately after mixing the liquid A and the liquid B.
It was shown to.

[0033]

[Table 4]

From this test, it was found that, immediately after mixing, the liquid can be fed in a state where the viscosity of the sealing material is low, and the liquid can be injected between the tail brushes in a state where it can be pumped or in a state where pipe transport is possible. This makes it possible to perform injection work from a distance. In addition, it is not necessary to use a plunger type (piston type) pump that fills the present oil-based sealing material (grease).

[0035]

According to the present invention, the danger of fire and the like can be avoided and the working environment can be improved by making the sealing material injected between the tail brushes of the shield machine and the entrance space at the time of starting off water-based. It does not cause groundwater pollution because it does not contain oils and fats. Moreover, it is inexpensive as compared with the oil-based sealing material, and the economical burden can be reduced even if the injection frequency is increased.

Since the sealing material of the present invention is excellent in pressure fluidity, it is easy to supply liquid and replenish the sealing material, the number of injection points can be reduced, and an automatic sealing material injection system and a management system can be introduced. It becomes easy to do. By mixing the liquid A containing no alkali stimulant and the liquid B containing the alkali stimulant and forming a sealing material immediately before pouring between the tail brushes, the pressure loss at the time of pouring can be further reduced. Since the injection circuit can be extended to arrange the injection equipment such as a pump and a tank behind the shield, the space in the tunnel can be effectively used.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a shield machine 1.

FIG. 2 is a partially enlarged view showing a state in which a sealing material is injected between tail brushes.

FIG. 3 is a diagram showing a state immediately before a sealing material is injected between tail brushes.
It is an enlarged view explaining the embodiment which mixes a liquid and B liquid.

FIG. 4 is an explanatory view schematically showing an injection system configured to automatically inject a sealing material between tail brushes.

FIG. 5 is an explanatory diagram showing a state before starting excavation when the shield machine starts.

FIG. 6 is an explanatory diagram showing a state immediately after the start of excavation when the shield machine starts.

FIG. 7 is an explanatory diagram showing a state where the tail portion just enters the ground when the shield machine starts.

FIG. 8 is an explanatory diagram showing a state where digging is further continued.

FIG. 9 is an explanatory diagram of an entrance space.

FIG. 10 is a graph comparing the change over time of the vane shear force of each sealing material.

FIG. 11 is a graph showing a resurrection state of the shearing force of the sealing material.

FIG. 12 is a graph showing a change in shear force of a sealing material prepared by mixing the liquid A and the liquid B.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Shield machine 2 Cutter 3 Ground 4 Segment 5 Skin plate 6 Tail brush 7 Sealing material 8 Injection circuit 8a First injection circuit 8b Second injection circuit 9 Backing material 10 Injection system 11 Control unit 12 Transmission 13 Valve 14 Liquid level sensor 20 Piercing wall 21 Starting port 22 Packing 23 Entrance space 24 Sealing material 25 Backing material 25 'Grout hole 26 Injection circuit 27 Pressure gauge 28 Pressure gauge P pump T tank Ta, Tb tank

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[Procedure amendment]

[Submission date] February 24, 1999

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claim 1

[Correction method] Change

[Correction contents]

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] Claim 6

[Correction method] Change

[Correction contents]

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] Claim 9

[Correction method] Change

[Correction contents]

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0001

[Correction method] Change

[Correction contents]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sealing material such as a tail used in a shielding method, and further relates to a shielding method using the sealing material and a sealing material injection system .
Concerning.

[Procedure amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0005

[Correction method] Change

[Correction contents]

[0005]

In order to achieve the above object, according to the first aspect of the present invention, there is provided a shield machine which moves between tail brushes moving along an outer peripheral surface of a segment assembled at a rear portion of a shield machine. A sealing material injected into the entrance space at the time of launching, wherein a silicate mineral containing 50% by weight or more of montmorillonite is 55 to 9%.
8% by weight, at least one selected from a water-soluble polymer thickener, sepiolite and attapulgite
~ 30% by weight, sodium hydroxide, magnesium oxide,
A sealing material mainly composed of an inorganic material containing 1 to 15% by weight of at least one alkali stimulant selected from calcium hydroxide, cement hydrated, reground and dried, and fly ash. A sealing material such as a tail which is excellent in pressurized fluidity and is mixed with water in a ratio of sealing material / (sealing material + water) = 0.1 to 0.3 by weight ratio.

[Procedure amendment 6]

[Document name to be amended] Statement

[Correction target item name] 0012

[Correction method] Change

[Correction contents]

The invention according to claim 6 is a seal injected into the entrance space between the tail brushes moving along the outer peripheral surface of the segment assembled at the rear part of the shield machine and the entrance space when the shield machine starts, in a state of being mixed with water. 55 to 98% by weight of a silicate mineral containing 50% by weight or more of montmorillonite, 1 to 30% by weight of at least one selected from a water-soluble polymeric thickener, sepiolite and attapulgite, Inorganic materials containing 1 to 15% by weight of at least one alkali stimulant selected from sodium oxide, magnesium oxide, calcium hydroxide, cement hydrated, reground and dried, and fly ash This is a seal material.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiroshi Ishimaru 1-3-8 Moto-Akasaka, Minato-ku, Tokyo Kashima Construction Co., Ltd. Tokyo Branch (72) Inventor Fumio Imatari 2-19 Tobita Shibi, Chofu-shi, Tokyo 1 Kashima Construction Co., Ltd. Technical Research Institute (72) Inventor Hiromasa Igarashi 2-19-1, Tobita-Shi, Chofu-shi, Tokyo Kashima Construction Co., Ltd. Technical Research Institute (72) Inventor Muneo Yoshimura 1-2-2 Moto-Akasaka, Minato-ku, Tokyo No. 7 Kashima Construction Co., Ltd. (72) Inventor Tsutomu Imagawa 1-2-7 Moto-Akasaka, Minato-ku, Tokyo Kashima Construction Co., Ltd. (72) Inventor Kaname Aoyama 1-8 Kandanishikicho, Chiyoda-ku, Tokyo Sumitomo Osaka Cement Co., Ltd. (72) Inventor Yasuo Watanabe 3-6-18 Higashi-Nihonbashi, Chuo-ku, Tokyo Bent Night Sangyo Co., Ltd.

Claims (11)

[Claims] 1. A sealing material injected into a space between tail brushes moving along an outer peripheral surface of a segment assembled at a rear portion of a shield machine and an entrance space when the shield machine starts, wherein montmorillonite is 50% by weight or more. 55 to 98% by weight of a silicate mineral containing 1 to 30% by weight of at least one selected from a water-soluble polymer-based thickener, sepiolite and attapulgite, sodium hydroxide, magnesium oxide, calcium hydroxide,
A seal material containing 1 to 15% by weight of at least one alkali stimulant selected from hydrated cement, re-crushed and dried, and fly ash,
Seal material / (seal material + water) = 0.1 ~ by weight ratio
A sealing material such as a tail mixed with water at a ratio of 0.3. 2. The tail according to claim 1, wherein the water-soluble polymeric thickener is at least one selected from water-soluble cellulose ethers such as carboxymethylcellulose and methylcellulose, natural gums and artificial gums. Etc. sealing material. 3. The sealing material for a tail or the like according to claim 1, wherein the sealing material further contains 5% by weight or less of an anionic coagulant. 4. The method according to claim 1, further comprising short fibers of at least one selected from vinylon, polypropylene, acrylic and cotton and having a length of 10 mm or less.
Or a sealing material such as a tail according to any of 3. 5. The method according to claim 1, further comprising a rust preventive material.
A sealing material such as a tail according to any one of 2, 3, and 4. 6. A seal material which is injected in a state mixed with water into a space between tail brushes moving along the outer peripheral surface of a segment assembled at a rear portion of the shield machine or into an entrance space when the shield machine starts moving, 55-55 silicate minerals containing at least 50% by weight of montmorillonite
98% by weight, 1 to 30% by weight of at least one selected from a water-soluble polymer-based thickener, sepiolite and attapulgite, hydrated sodium hydroxide, magnesium oxide, calcium hydroxide, cement and re-crushed A sealing material containing 1 to 15% by weight of at least one alkali stimulant selected from dried and fly ash. 7. A sealing material such as a tail according to claim 1, 2, 3, 4 or 5, between a tail brush moving along an outer peripheral surface of a segment assembled to a rear part of the shield machine. A shield method characterized by injection and sealing the tail of the shield machine. 8. The method according to claim 7, wherein the sealing material is prepared by mixing a liquid A containing no alkaline stimulant and a liquid B containing the alkaline stimulant immediately before pouring the sealing material between the tail brushes. The shield method described. 9. The liquid A comprises a silicate mineral containing at least 50% by weight of montmorillonite, a water-soluble polymer thickener,
A mixture of at least one selected from sepiolite and attapulgite at a weight ratio of 1000: 0 to 100 and prepared at a weight concentration of 10 to 30% with respect to water. 10 to 100 of a silicate mineral containing 50% by weight or more of montmorillonite, 1 to 10 of at least one selected from a water-soluble polymer thickener, sepiolite and attapulgite, sodium hydroxide, Magnesium oxide,
A liquid prepared by mixing 10 to 100 alkali stimulants consisting of at least one selected from calcium hydroxide, cement hydrated, re-crushed and dried, and fly ash. Liquid A and B when making
The mixing ratio of the liquids is A: B liquid = 1000: 50 to 3 by volume ratio.
The method according to claim 7, wherein the number is 00. 10. A tank for storing a sealing material such as a tail according to any one of claims 1, 2, 3, 4 and 5, and a sealing material in the tank for a segment assembled at a rear portion of a shield machine. Injection circuit for injecting between the tail brushes moving along the outer peripheral surface, pump for pumping the sealing material, sensor for detecting the sealing material injection pressure, and when the sealing material injection pressure exceeds the reference value An injection system comprising a control unit for stopping the pump and operating the pump when the injection pressure of the sealing material has not reached the reference value. 11. The injection system according to claim 10, wherein the sensor is arranged in the injection circuit.