JPH06257379A - Drilling method for tunnel and the like - Google Patents

Abstract

PURPOSE:To construct a lining body having excellewnt workability and sure pressure proofing before drilling of a tunnel or the like, concerning a drilling method of a tunnel or the like. CONSTITUTION:A drilling bit 43 is engaged with the extreme ends of a double drilling tube 35 provided with side injection nozzles on the circumferential wall of the extreme end part, and a reinforcing steel tube 57 inserted in the double tube. They are inserted into the circumferential edge part of the ground to be excavated facing to the pit part drilling direction, water W poured into the steel tube is let flow from the extreme end of the drilling bit so as to drill up to a predetermined position, thereafter, hardening material of high pressure is forcedly fed between the inner tube 37 and the outer tube 39 of the double drilling tube is jetted from the injection nozzles 41, and while drilling the ground, the double drilling tube is detached from the drilling bit and retreated while rotating. Hereby, columnar hardened layers are constructed adjacent to surrounding of the double drilling tube insertion locus along the circumferential edge of the pit opening, and hence a lining body is constructed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of excavating tunnels, underground tunnels and the like.

[0002]

2. Description of the Related Art Conventionally, in excavation work for tunnels, underground tunnels, etc., prior to excavation of tunnels, etc., by constructing an arched lining body with concrete etc. along the tunnel cross section in front of the face, An excavation method for improving the stability of the face is disclosed in Japanese Examined Patent Publication No. 4-42520 or JP-A-3-20898.
No. 6, for example.

In the excavation method disclosed in Japanese Examined Patent Publication No. 4-42520, as shown in FIGS. 7 and 8, an injection pipe 3 provided with a side injection nozzle 1 on the tip side is directed in the advancing direction of mine excavation. And insert it into the peripheral edge portion B of the ground A to be excavated, and when the hole is drilled to a predetermined position, the hardening material is pressure-fed to the injection pipe 3 and ejected from the injection nozzle 1 as a high-pressure jet flow. By rotating and retreating, as shown in FIG. 9, the columnar hardened layer 5 formed by mixing the soil around the injection pipe insertion locus and the hardened material is successively formed along the periphery of the pit opening to form an arched lining. Repeating the steps of constructing the body 6 and excavating the ground A to be excavated on the inside of the lining body 6 constructed in this way within the range of the length of the lining body 6 or less to perform the support lining. , The tunnel is excavated one after another.

In the figure, 7 is a drilling device used in the above-mentioned excavation method, and the drilling device 7 is provided with the injection pipe 3 and the rotary drive mechanism 9 for rotationally driving the injection pipe 3. Has a perforation bit 11 and a side injection nozzle 1 at its tip, and
The rear end portion is connected to a supply portion for a hardening material and lubricating water via a swivel 13. The injection pipe 3 is laterally supported on a position operating mechanism 17 which tilts the universal joint 15 in the front-rear and left-right directions using the universal joint 15 as a support shaft, and the position operating mechanism 17 is installed on a base rod 19 that rotates up and down. The self-propelled base 21 that is self-propelled by the caterpillar
Is loaded on.

The drilling device 7 thus constructed
Running in front of the target ground, the height direction is determined by the base rod 19, and the position of the target ground wall surface by the elevation angle and the left and right inclination is determined by the position operating mechanism 17, and then the injection pipe 3 is first tested. Lubricating water is pumped at low pressure and rotated,
The above process is carried out by inserting the ground A into the peripheral edge B as shown in FIG.

On the other hand, in the excavation method disclosed in Japanese Unexamined Patent Publication No. 3-208986, as shown in FIG. 10, a rod 25 having a drill bit 23 attached to the tip is inserted into a pipe 27, and the tip is drilled. After the bit 23 is projected from the pipe 27 and coaxially held by the rotary unit, the rod 25 and the pipe 27 are simultaneously inserted into the ground 29, and the hardening material is jetted from the lateral jet nozzle 31 at the tip of the rod at a high pressure. do it,
A cylindrical hardened layer 33 formed by mixing the soil around the rod insertion locus and the hardened material is provided on the periphery of the pit opening, and then the rod 25 is pulled out from the pipe 27, and as shown in FIG. It is used as a core material.

[0007]

Thus, the pipe 27 is thus formed.
As the core material of the cylindrical hardened layer 33, the strength of the cylindrical hardened layer 33 is improved and the pressure resistance against the ground is increased as compared with the cylindrical hardened layer 5 shown in FIG.
When 5 is held by the rotary unit, since the rod 25 is long, the tip side (perforation bit 23 side) may be bent by its own weight and come into contact with the inner circumference of the tube 27.
When the rod 25 comes into contact with the inner circumference of the pipe 27 in this manner, the rod 25 and the pipe 27 that rotate in opposite directions are rotated.
There is a risk that the rotation will be hindered and the soil cannot be discharged smoothly between the rod 25 and the pipe 27.

On the other hand, if a spacer is interposed in the pipe 27 to prevent the rod 25 and the pipe 27 from coming into contact with each other, the spacer may hinder the discharge of soil. Also, FIG.
Although the pipe 27 has its rear end side supported by the ground 29, as shown in FIG.
Since there is a gap between the outer periphery of the pipe and the ground 29, if the rod 25 is pulled out from the pipe 27, the pipe 27 cannot be held at a predetermined inclined angle with respect to the level line, and the pipe 27 cannot be held.
May shift in the direction of the arrow, and if the pipe 27 shifts in this way, there is also the possibility that the set strength (pressure resistance) of the cylindrical hardened layer 33 cannot be secured.

The present invention has been devised in view of such circumstances, and prior to excavation of a tunnel or the like, a columnar hardened layer is formed in front of the cutting face along the tunnel cross section and arched lining, as in the conventional case. It has excellent workability in constructing the body,
An object of the present invention is to provide a method for excavating a tunnel or the like that can construct a lining body having a reliable pressure resistance.

[0010]

In order to achieve such an object, a method for excavating a tunnel or the like according to the present invention is a double hole drilling which comprises an outer pipe and an inner pipe provided with a side injection nozzle on a tip peripheral wall. The drilling bit is engaged with the tip of the pipe and the reinforcing steel pipe inserted into the inner pipe of the double-drilled pipe, these are inserted in the peripheral edge of the ground to be excavated in the direction of the excavation of the pit, and injected into the steel pipe. After water is made to flow from the tip of the boring bit and drilled to a predetermined position, a high-pressure hardened material that has been pressure-fed between the inner and outer pipes of the double-drilled pipe is jetted from the jet nozzle to lay the ground. After excavation, the double-drilled pipe was rotated and removed from the drill bit to be retracted, so that a cylindrical hardened layer was sequentially formed around the double-drilled pipe insertion track along the periphery of the hole opening. The lining body is constructed in an arch shape, and the ground to be excavated is within the length of the lining body. It is intended to continue to advance.

In the excavation method for a tunnel or the like according to claim 2, a drainage mud hole is provided in the peripheral wall of the reinforcing steel pipe, and when excavating the ground with a hardening material, the mixed mud sludge of soil and the hardening material is drained. It is discharged to the outside through.

[0012]

According to the excavation method for a tunnel or the like according to the first aspect, the boring bit is engaged with the tips of the double boring pipe and the reinforcing steel pipe, and water is caused to flow out from the tip of the boring bit to drill a hole to a predetermined position. After that, the high-pressure hardening material pumped between the inner pipe and the outer pipe of the double-drilled pipe is ejected from the injection nozzle to excavate the ground, and the double-drilled pipe is rotated while the drill bit is removed from the drill bit. By removing and retracting, a columnar hardened layer is formed around the double hole pipe insertion track along the periphery of the pit opening.

By constructing such a columnar hardened layer sequentially adjacent to the insertion path of the double-drilled pipe to construct the lining body in an arch shape, the face is stabilized. According to the excavation method according to the second aspect, when excavating the ground with the hardened material, the mixed sludge of soil and the hardened material is positively discharged to the outside through the mud hole.

[0014]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a schematic cross-sectional view of a hole drilling device used in the first embodiment of the method of the present invention, in which 35 is a double hole drilling pipe composed of an inner pipe 37 and an outer pipe 39, and a tip side of the outer pipe 39. A side injection nozzle 41 for injecting cement milk at high pressure is provided on the peripheral wall, and the double drilling pipe 35 is used as the position operating mechanism 17 and the base rod 19 in the drilling device 7 shown in FIG.
It is loaded on a self-propelled base by a device similar to.

A drill bit 43 is fitted to the tip of the double drill pipe 35 so that the double drill pipe 35 is rotated by a rotation driving mechanism (not shown) so that the drill bit 43 can move the ground 45. It is designed for drilling. still,
Reference numeral 47 is a water supply hole provided in the drill bit 43.

A cement milk supply hose 53 and a water supply hose 55 are connected to the rear end side of the double-drilled pipe 35 via swivels 49 and 51. As shown in FIG. The high-pressure cement milk S pressure-fed from 53 passes between the inner pipe 37 and the outer pipe 39 and is jetted from the side jet nozzle 41 at right angles to the drilling direction.

Reference numeral 57 is a reinforcing steel pipe inserted into the inner pipe 37 of the double-drilled pipe 35, the tip of which is the above-mentioned drill bit 43.
It is screwed onto and is arranged on the same axis as the inner pipe 37 and the outer pipe 39 of the double-drilled pipe 35. When the double-drilled pipe 35 is rotated by the rotation driving mechanism, the steel pipe 57 is interlocked with this. Are designed to rotate in the same direction. Further, as shown in FIG. 1, the rear end of the steel pipe 57 is a free end in the inner pipe 37, and when the water W is supplied from the water supply hose 55 into the double-drilled pipe 35, the water W is The water is ejected from the water supply hole 47 in the drilling direction through the steel pipe 57.

Thus, one embodiment of the method of the present invention is carried out by the drilling device having the above construction. First, as in the conventional case, the self-propelled base equipped with the above-mentioned drilling device is run in front of the target ground, the height direction of the double drilling pipe 35 is determined by the base rod, and the position operating mechanism is also used to double the height direction. The elevation angle of the hole-drilling pipe 35 and the position of the target ground wall surface by the left-right inclination are determined.

Then, the double-drilling pipe 35 is rotated by the rotary drive mechanism to be inserted into the peripheral portion of the ground to be excavated, and at the same time, the water W supplied from the water supply hose 55 is drilled from the water supply hole 47 of the drill bit 43. The ground 45 is drilled by ejecting in the direction.

Then, as shown in FIG. 1, after finishing the drilling of the ground 45 to a predetermined position, the supply of the water W is stopped, and then,
As shown in FIG. 2, cement milk S is pumped from the cement milk supply hose 53 between the inner pipe 37 and the outer pipe 39,
At the same time as the high-pressure cement milk S is jetted from the side jet nozzle 41, the double-drilled pipe 35 is rotated and retracted.

By thus rotating the double-drilled pipe 35 and retracting it, as shown in FIG.
Disengages from the perforation bit 43, and the side jet nozzle 4
The ground 45 is sequentially excavated by the high-pressure cement milk S ejected from No. 1, and the cylindrical hardened layer 59 having the steel pipe 57 as the core material as shown in FIG. Is created in. The sludge excavated with the cement milk S is discharged to the outside from between the outer pipe 39 of the double-drilled pipe 35 and the ground 45.

By repeating these steps in sequence to form the columnar hardened layer 59 adjacently, a lining body similar to the lining body 6 in FIG. 9 is constructed in an arch shape along the periphery of the pit opening. As the stability of the face is ensured,
The excavation of the tunnel will be performed by excavating and excavating within the range of the length of the lining body on which the ground to be excavated is constructed.

As described above, also according to one embodiment of the method of the present invention, the columnar hardened layer 59 having the core material is successively formed adjacently to construct the arched lining body along the pit opening peripheral edge. However, according to the present embodiment, as shown in FIG. 3, the steel pipe 57 as the reinforcing core material is securely held at the predetermined position with respect to the level line by the drilling bit 43 driven into the ground 45. As compared with the conventional example shown in FIG. 11, it is possible to reliably manufacture the cylindrical hardened layer 59 having a predetermined breakdown voltage.

Of course, as described above, the sludge produced when the high-pressure cement milk S is jetted from the side jet nozzle 41 to excavate the ground is the outer pipe 39 of the double-drilled pipe 35 and the ground 45. Since it is quickly discharged from the gap to the outside, the sludge sludge treatment is smoother than the conventional one, and the double-drilled pipe 35 and the steel pipe 57 rotate in the same direction at the time of drilling. Even if the rear end side touches the inner circumference of the inner pipe 37 by its own weight, it does not hinder the drilling work. As a result, according to the present embodiment, the drilling work and the lining body are made more than conventional ones. It has the advantage that the construction work can be done smoothly.

FIG. 4 shows a drilling device used in the second embodiment of the method of the present invention. In this embodiment, a plurality of mud holes 61 are provided in the peripheral wall in place of the steel pipe 57 as the reinforcing core material. Using the steel pipe 57A, the mixed sludge S'of cement milk S and soil is quickly discharged to the outside through each sludge hole 61.

That is, depending on the ground, the side injection nozzle 4
When the high-pressure cement milk S is ejected from No. 1, a large pressure is generated in the ground, which may adversely affect the ground surface and the like. Therefore, in the present embodiment, as shown in FIG. 4, the mixed sludge S of soil and cement milk S excavated by the jet of cement milk S is used by using a steel pipe 57A having a plurality of sludge holes 61 provided on the peripheral wall. ′ Is positively discharged to the outside from the double-drilled pipe 35 through the mud hole 61.
In the figure, 63 is a swivel mounted on the rear end side of the double-drilling pipe 35. The swivel 63 is supplied with water W at the time of drilling by the double-drilling pipe 35 and the ground 45 made of cement milk S. A supply / discharge hose 65 for discharging the mixed sludge S ′ to the outside at the time of excavation is connected. Since the other structures are the same as those of the first embodiment, the same components are designated by the same reference numerals and their description will be omitted.

Thus, also in this embodiment, the method of forming the cylindrical hardened layer 59 covering the steel pipe 57A is the same as that of the first embodiment described above. First, the double drilled pipe 35 is rotated by the rotary drive mechanism. Rotate and insert into the peripheral edge of the ground to be excavated, and at the same time supply and discharge hose 6
The water W supplied from 5 is jetted in the drilling direction from the water feed hole 47 of the drill bit 43 to drill the ground 45.

Then, as shown in FIG. 4, after the boring of the ground 45 is completed to a predetermined position, the supply of the water W is stopped, and then,
As shown in FIG. 5, cement milk S is pumped from the cement milk supply hose 53 between the inner pipe 37 and the outer pipe 39,
At the same time as the high-pressure cement milk S is jetted from the side jet nozzle 41, the double-drilled pipe 35 is rotated and retracted.

By thus rotating the double-drilled pipe 35 and retracting it, as shown in FIG.
Disengages from the perforation bit 43, and the side jet nozzle 4
The ground 45 is sequentially excavated by the high-pressure cement milk S ejected from No. 1, and the mixed sludge S ′ of the soil and the cement milk S is discharged.
However, when it is positively discharged from the double-drilled pipe 35 through the drainage hole 61 through the supply / discharge hose 65, a cylindrical hardened layer 59 having a steel pipe 57A as a core material is formed in the pit portion as shown in FIG. It will be created around the double drilled pipe insertion track along the periphery of the opening.

As described above, also in this embodiment, the columnar hardened layer 59 having the steel pipe 57A as the core material is successively formed adjacently to construct the arched lining body along the periphery of the pit opening. The steel pipe 57A as a reinforcing core material is securely held at a predetermined position with respect to the level line by the drilling bit 43 driven into the ground 45.
A cylindrical hardened layer 59 having a predetermined withstand voltage as compared with the conventional example shown in FIG.
It has the effect that it can be manufactured reliably.

Of course, as described above, the soil produced when the high pressure cement milk S is ejected from the side jet nozzle 41 to excavate the ground becomes the mixed sludge S'mixed with the cement milk S. , Double-drilled pipe 3 through sludge hole 61
5. Since it is positively discharged from the supply / discharge hose 65 to the outside, there is an advantage that a large pressure is prevented from being generated in the ground and the lining body can be constructed smoothly without adversely affecting the ground surface and the like.

[0032]

As described above, according to the invention described in each of the claims, prior to excavation of a tunnel or the like, a columnar hardened layer is provided in front of the cutting face along the tunnel cross section with concrete to form a lining body. In constructing, it has an excellent workability as compared with the conventional one, and has an effect that a cylindrical hardened layer having a sufficient pressure resistance can be formed.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a hole drilling device used in a first embodiment of the method of the present invention.

FIG. 2 is an explanatory diagram showing a ground excavation state using cement milk.

FIG. 3 is a cross-sectional view of a formed cylindrical hardened layer.

FIG. 4 is a sectional view of a drilling device used in a second embodiment of the method of the present invention.

FIG. 5 is an explanatory diagram showing a state of excavation of the ground using cement milk.

FIG. 6 is a cross-sectional view of the formed cylindrical hardened layer.

FIG. 7 is a side view of a conventional drilling device used for tunnel excavation work.

FIG. 8 is a cross-sectional view of the tunnel.

FIG. 9 is a cross-sectional view of the tunnel showing the construction status.

FIG. 10 is an explanatory view showing a conventional method for forming a cylindrical hardened layer.

FIG. 11 is a cross-sectional view of a conventional cylindrical hardened layer.

[Explanation of symbols]

 35 Double Drilling Pipe 37 Inner Pipe 39 Outer Pipe 41 Side Injection Nozzle 43 Perforation Bit 49, 51, 63 Swivel 53 Cement Milk Supply Hose 55 Water Supply Hose 57, 57A Steel Pipe 59 Cylindrical Hardening Layer 61 Drainage Hole 65 Supply and Discharge hose

Claims (2)

[Claims] 1. A double-drilled pipe consisting of an outer pipe and an inner pipe provided with lateral injection nozzles on the peripheral wall of the tip, and a drill bit at the tip of a reinforcing steel pipe inserted into the inner pipe of the double-drilled pipe. Insert them into the peripheral edge of the ground to be excavated in the direction of the pit excavation direction, let the water injected into the steel pipe flow out from the tip of the piercing bit and make a hole to the specified position, then double dig By excavating the ground by ejecting the high-pressure hardening material pumped between the inner tube and the outer tube of the hole pipe from the injection nozzle, by removing the double hole pipe from the drill bit and retracting it while rotating it. , The columnar hardened layer along the periphery of the pit opening is sequentially constructed adjacently around the double hole drilling pipe insertion path to construct the lining body in an arched shape, and the ground to be excavated is within the length of the lining body A method of excavating tunnels, etc., characterized by digging in. 2. A mud discharge hole is provided in the peripheral wall of the reinforcing steel pipe, and when excavating the ground with a hardening material, mixed mud mud of soil and hardening material is discharged to the outside through the mud discharging hole. The excavation method for tunnels described in 1.