JP3459814B2 - Tunnel auxiliary method - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a tunnel auxiliary construction method. More specifically, the present invention relates to a tunnel auxiliary construction method capable of preventing solidification or blockage of a two-liquid-mixing type coagulant in a mixing unit and reliably injecting the coagulant into a predetermined location.

[0002]

2. Description of the Related Art Conventionally, in an auxiliary construction method for tunnel construction, a hollow pipe-shaped rock bolt or a perforated steel pipe is inserted into a hole formed in rock (ground) in order to prevent falling rock. A two-part type rock-solidifying liquid consisting of urethane foam resin and so-called silica resin (resin containing silicon dioxide) is injected into it to solidify the holes and the surrounding rocks. There is.

The above-mentioned two-liquid type rock solidifying liquid is pressure-fed by a pouring machine through a hose in the form of two separate feeds, joined at a mixing unit at the tip of the hose, and then a hollow pipe or an injection located downstream. The mixture is mixed and stirred in the tube for use, and finally ejected from the nozzle into the rock mass (ground).

In the conventional tunnel auxiliary construction method, as shown in FIG.
As shown in, a mixing unit made of T-type cheese (T-type tube) is used. In the hollow main body 21, two introduction ports 22 and 23 are formed at positions opposed to each other in the main body 21, and a T-shaped confluence portion 24 is formed substantially in the center of the main body 21. One discharge port 25 is formed in a portion branched from the merging portion 24 in.

Further, in the mixing unit of FIG. 3, 90 ° elbows 26 and 27 which are bent at an angle of approximately 90 ° are screwed into the introduction ports 22 and 23, respectively. Further, a coupler 28 for connecting a hose or the like or a nozzle or the like is screwed to the discharge port 25.

[0006]

However, in the tunnel auxiliary construction method using such a mixing unit, two liquids of the rock solidifying chemical liquid collide with each other at the confluence portion 24 inside the main body 21 made of T-type cheese and almost merge with each other. After that, since the mixed liquid changes its direction by 90 ° and goes to the discharge port 25,
Large pressure loss occurs. Therefore, it is necessary to increase the injection pressure. Further, when the 90 ° elbows 26 and 27 are fitted in the inlets 22 and 23, a large pressure loss occurs at the 90 ° elbows 26 and 27, so that the injection pressure needs to be further increased.

Further, the two liquids are partially mixed and stirred by substantially head-on collision inside the T-shaped merging portion 24. Therefore, there is a problem that the chemical liquid is solidified in the mixing unit and the discharge port 25 is blocked when the solidification time of the chemical liquid is short such as in summer. Due to this problem, the injection work is hindered, the number of mixing units used is increased, and the problem is economically caused.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a tunnel auxiliary construction method capable of surely injecting a two-liquid mixing type coagulant into a predetermined location.

[0009]

According to the tunnel auxiliary construction method of the present invention, a hollow pipe-shaped rock bolt or a perforated steel pipe is inserted into a hole formed in a rock mass, and pressure is fed from a pouring machine through separate hoses. The two liquid rock solidifying chemicals of the two liquid type that have been merged are combined in a mixing unit connected to the tip of the hose, and the combined rock solidifying liquid is injected into the lock bolt or the perforated steel pipe. 0.5-50 kg / cm ²
.A tunnel auxiliary construction method for injecting about G to consolidate the hole and the rock around it, wherein the mixing unit has a hollow body with two inlets and one outlet formed , and the one of the body of the merging portion, the two inlets to the extending portion caused a substantially U-shaped or substantially V-shaped, the converging portion of the interior of the body through the discharge port
It is characterized in that a partition plate is provided along the axial direction .

Each of the two inlets of the main body has 135
It is preferable that an elbow having an obtuse angle that is bent at about a degree or more is attached.

[0011]

It is preferable that the length of the partition plate projecting into the merging portion is about 10 to 50 mm.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Next, the tunnel auxiliary construction method of the present invention and the mixing unit used in the construction method will be described in detail with reference to the drawings. FIG. 1 is a sectional explanatory view showing an embodiment of a mixing unit used in the tunnel auxiliary construction method of the present invention, and FIG. 2 is a sectional explanatory view showing another embodiment of the mixing unit used in the tunnel auxiliary construction method of the present invention.

In the tunnel auxiliary construction method of the present invention, hollow pipe-shaped rock bolts or perforated steel pipes are inserted into a plurality of holes formed in rock (ground) at intervals of, for example, about 0.5 to 3 m. . Then, the two liquids of the rock-solidifying liquid of the two-liquid type are pressure-fed through the hose separately from the injection machine. The two liquids are combined in a mixing unit connected to the tip of the hose, and then injected into a hollow pipe-shaped rock bolt or perforated steel pipe downstream at an injection pressure of about 0.5 to 50 kg / cm ² · G. And mix and stir. Finally, the rock-solidifying chemical liquid mixed in the rock is ejected from the nozzle and hardened to solidify or seal it for stabilization.

In the tunnel auxiliary construction method of the present invention, the combination of the two liquids which are mixed and stirred in the mixing unit is appropriately selected from the combination of the two liquids which are the components of the conventionally used two-liquid type rock solidifying liquid.

For example, in addition to the above-mentioned combination of the urethane foam resin and the silica resin, a combination of a two-component mixed resin such as an epoxy resin and a two-component cement type can be selected.

Next, the mixing unit used in the auxiliary method of the present invention will be described.

The mixing unit shown in FIG. 1 has a hollow body 1 having two inlets 2, 3 and one outlet 4.
In the main body 1, there is formed a merging portion 5 in which the portions extending to the two inlets 2 and 3 are substantially U-shaped. Further, a coupler 8 for connecting a hose or the like is provided to a discharge port 4 formed at a portion branched from a substantially middle position of a portion of the merging portion 5 extending in a substantially U shape.
Or a nozzle or the like is screwed on.

The mixing unit shown in FIG. 2 is a Y-type cheese (Y-type tube) in which two introduction ports 2, 3 and one discharge port 4 are formed in a hollow main body 1, and Inside the main body 1, there is formed a merging portion 5 in which a portion extending to the two introduction ports 2 and 3 has a substantially V shape. Further, a coupler 8 for connecting a hose or the like or a nozzle or the like is screwed to a discharge port 4 formed at a portion branched from a substantially intermediate position of a portion of the merging portion 5 extending in a substantially V shape.

The mixing unit shown in FIGS.
In the merging portion 5 inside the container, the portion extending to the two inlets 2 and 3 has a substantially U-shape or a substantially V-shape, so that the chemical solution flows in from the two inlets 2 and 3. The resistance at the time of mixing and stirring can be reduced, and as a result, the pressure loss can be significantly reduced.

The main body 1 is made of metal, resin or the like, and the opening angle θ (see FIG. 2) of the merging portion 5 is set to an acute angle in consideration of the resistance at the time of merging and the size of the mixing unit main body. Is preferred.

Further, in the example of FIG. 2, since the elbows 6 and 7 having obtuse angles bent by about 135 ° or more are respectively screwed into the two inlets 2 and 3 of the main body 1, the conventional 90 °. The pressure loss at the elbow can be significantly reduced as compared with the elbow (for example, the portions indicated by reference numerals 26 and 27 in FIG. 3). On the other hand, when the merging portion 5 has a substantially U-shaped portion as shown in FIG. 1, the obtuse angle elbows 6 and 7 can be omitted, but they may be attached.

Further, at the confluence portion 5 inside the main body 1 of FIGS. 1 and 2, a partition plate 9 is provided along the axial direction passing through the discharge port 4.
Is provided. With this partition plate 9, the introduction port 2,
The two liquids introduced from No. 3 are discharged from the discharge port 4 inside the merging section 5.
It is possible to reduce the pressure loss due to the pressure-feeding of the two liquids by making each of them into a separate state from before to the point of discharge and joining them at the time of discharge.

Moreover, the partition plate 9 is used to prevent the two liquids from merging inside the merging portion 5, thereby preventing the reaction solidification of the two liquids in the mixing unit and the solidification of the discharge port 4. It is possible to solve the problem and reduce the number of mixing units used.

If the length L (see FIG. 2) of the partition plate 9 protruding into the merging portion 5 is about 10 to 50 mm, the two liquids are not mixed inside the merging portion 5 and are discharged. It is preferable because the merging can be performed with good timing at the time (immediately after exiting the discharge port 4).

The partition plate 9 can be made of iron, resin or the like. For example, a cut is made in a part of the main body 1, the partition plate 9 is inserted into the cut, and then the partition plate 9 is welded. It is provided inside the main body 1 by being fixed to the body 1 and closing the cut.

Next, an example of use of the above mixing unit will be described. First, the component (A) consisting of an aqueous alkali silicate solution, the component (B) consisting of an organic polyisocyanate compound, a water-soluble aliphatic tertiary amine having a molecular weight of 120 or more and a nitrogen atom number of 2 or more, or water-soluble Using a proportional compounding type pump capable of controlling the injection amount, pressure, compounding ratio, etc. of the component (C) consisting of an alicyclic tertiary amine and the component (D) consisting of a polyol component, the above component (A), (C) ) Component and a mixture of (D) component,
Put the component (B) in a separate tank, and pass a perforated rock bolt or injection rod through a predetermined location (for example, a plurality of holes drilled at intervals of about 0.5 to 3 m) such as bedrock,
Then, using the mixing unit of the present embodiment,
Injection pressure 0.5 to 50 kg / cm ² · into the lock bolt or injection rod while mixing and stirring each component in the tank.
Inject at about G. Thereby, a predetermined amount of the mixture of the components (A), (C) and (D), and (B)
The components can be uniformly mixed, and can be injected and permeated into a predetermined unstable rock mass or a ground site to be hardened or sealed by hardening and then stabilized.

[0028]

EFFECTS OF THE INVENTION According to the present invention, by adopting a branch pipe in which two of the merging portions extend into a substantially U-shape or a substantially V-shape, it is possible to compare with a conventional T-type cheese. Therefore, the pressure loss can be significantly reduced.

Further, if a partition plate is provided at the confluent portion of the main body, it is possible to prevent the reaction solidification of the two liquids in the mixing unit. As a result, it is possible to solve the problem of blockage of the discharge port, and at the same time, it is possible to reduce the number of mixing units used.

[Brief description of drawings]

FIG. 1 is a cross-sectional explanatory view showing an embodiment of a mixing unit used in a tunnel auxiliary construction method of the present invention.

FIG. 2 is a sectional explanatory view showing another embodiment of the mixing unit used in the tunnel auxiliary construction method of the present invention.

FIG. 3 is a cross-sectional view of a conventional mixing unit.

[Explanation of symbols]

1 body A few inlets 4 outlets 5 Confluence section 6, 7 elbow 9 partition boards

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-5-272126 (JP, A) JP-A-53-61111 (JP, A) JP-B-4-49640 (JP, B2) (58) Field (Int.Cl. ⁷ , DB name) E21D 20/00 E02D 3/12 101

Claims (3)

(57) [Claims] 1. A rock-solid rock bolt or a perforated steel pipe in the shape of a hollow pipe is inserted into a hole formed in rock, and a two-liquid type rock-solidifying chemical liquid is pressure-fed from an injector through separate hoses. The two liquids are combined in a mixing unit connected to the tip of the hose, and the combined rock solidifying liquid is injected into the lock bolt or the perforated steel pipe at a pressure of 0.5 to 50 kg.
A tunnel auxiliary construction method for solidifying the hole and rock around it by injecting at about 1 / cm ² · G, wherein the mixing unit has two introduction ports and one discharge port formed in a hollow body. are those which are, the one of the merging portion of the inner body, the two inlets to the extending portion caused a substantially U-shaped or substantially V-shaped, the converging portion of the interior of the body, the discharge port Axis direction through
A tunnel auxiliary construction method characterized in that a partition plate is provided along the line . 2. Each of the two inlets of the main body has 13
The tunnel auxiliary construction method according to claim 1, wherein an obtuse elbow bent at about 5 ° or more is attached. 3. The tunnel auxiliary construction method according to claim 2 , wherein a length of the partition plate protruding into the confluence portion is about 10 to 50 mm.