JP2940402B2 - Rock tunnel excavation method using arch machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to the excavation of rock tunnels,
Such as those related to the rock tunnel excavation construction method suitable for drilling rock tunnel large section such diameter 20 to 30 m.

[0002]

2. Description of the Related Art A tunnel construction method for forming a tunnel by excavating the ground so that structures such as roads and railways are provided in the ground is based on ground geology and groundwater conditions, the shape and length of a tunnel cross section, and other factors. Various construction methods are selected in consideration of construction conditions and the like. Conventionally, as a method of excavating rock masses from soft rock to hard rock, for example, conventionally, for example, blasting by blasting, or forming a large number of drilling holes on the face face, and inserting a wedge-shaped rock drill into the rock to divide the rock. BACKGROUND ART A construction method and a mechanical excavation method using various rock excavation machines such as a tunnel excavator and a breaker are known.

In the excavation work of a tunnel for such a bedrock, for example, when a tunnel having a diameter of 20 to 30 m is excavated and formed, it is difficult to excavate the excavated cross section at a time. In addition, in order to efficiently perform the excavation work of such a large cross section, each divided cross section is sequentially excavated in accordance with a predetermined sequence such as an upper half cross section advanced excavation method, a pit advanced excavation method, or the like.

[0004]

However, in excavation by blasting, excavation is efficiently and economically performed with a small amount of medicine so as not to delay the progress of the excavation plan, and excess excavation and the loosening of the ground are minimized. It is important to. Therefore, in order to perform blasting effectively, it is necessary to increase the free surface as much as possible and increase the amount of crushing with the same amount of medicine.

[0005] In the above-mentioned construction method using a wedge-shaped rock-cutting machine, the efficiency of the rock-cutting work can be improved by using the free surface. Has become.

Further, even in combination with a conventional mechanical excavation method using a rock excavation machine, it is difficult to efficiently excavate and form a large-section tunnel, and development of a new excavation technique for a large-section tunnel is desired. It is rare.

An object of the present invention is to solve the above problems, it is to provide a rock tunnel excavation construction method capable of safely and efficiently rapidly drilling forms a large cross-section tunnels.

[0008]

In order to achieve the above object, the present invention provides an arch-shaped self-propelled gantry and a self-propelled gantry.
Small size with multiple units slidably arranged along the arch on the front
An excavator, and a front-rearly mounted excavator
With a cutter head that also has a cutter on the side of the
With the gripper provided on the self-propelled platform to obtain from the ground side
An excavation method of a rock tunnel for forming a tunnel in a rock using an arch machine provided with the step of excavating an advanced shaft on both sides below an arch-shaped tunnel section, A step of forming an arch outer peripheral space portion by slidingly excavating an outer peripheral portion of a tunnel cross section in a ring-cut shape by an arch excavator equipped with an excavator slidably along the arch; Excavating the ground in the tunnel surrounded by the outer peripheral space (claim 1).

[0009] Further, in the rock tunnel excavation method of another invention, an arch-shaped self-propelled gantry and an arch on the front of the self-propelled gantry are provided.
A small excavator that is slidably arranged along the
It is provided on the front of the excavator so that it can move forward and backward, and
With a cutter head and a reaction force from the ground side
And a gripper provided on the self-propelled platform to obtain
Excavating an advanced shaft with tunnel excavators on both sides below the arched tunnel section using a drill excavator;
An arch excavator having an excavator slidably mounted along an arch on an arch-shaped base to slide and excavate an outer peripheral portion of a tunnel cross section in a ring-cut shape to form an arch outer peripheral space, and the arch outer peripheral space Dividing the inside into an outer layer and an inner layer, casting arch concrete as an outer layer to form an outer shell, and leaving a remaining arch outer peripheral space portion on the inner layer, and then freeing the remaining arch outer peripheral space portion Excavating the ground in the tunnel surrounded by the remaining arch outer peripheral space as a surface (claim 2).

[0010]

[0011]

In the excavation method according to the first aspect of the present invention, after an advanced pit is preliminarily excavated on both sides below the tunnel section by a tunnel excavator, the excavator is excavated while sliding the outer peripheral portion of the tunnel section in a ring cut shape. . Therefore, the arch outer peripheral space along the arch of the large-section tunnel can be formed economically with a small number of excavators.

In the excavation method according to the second aspect, the arch outer peripheral space is divided into an outer layer and an inner layer.
For example, arch concrete is cast by spraying or by a slide center which also serves as a reaction force receiving member to form an outer shell, and a remaining arch outer peripheral space is left in the inner layer. Therefore, when excavating the ground in the outer shell, the remaining arch outer peripheral space contributes as a free surface for facilitating excavation, while the outer layer exists as precedent arch concrete during excavation. Therefore, a large-section tunnel can be excavated safely and rapidly. Further, since this arch concrete can also serve as a lining, no interior is required and the entire construction period can be shortened.

In the arch excavator according to the first and second aspects, one or a plurality of small excavators are provided at the front of the arch-shaped self-propelled gantry so that the excavator can move along the arch. The cutter head is capable of moving forward and backward, and the cutter head is also provided with a cutter on the side of the head.
Therefore, for example, it is possible to use a method in which the reaction force is taken from the ground side by the gripper, and the excavator is shifted in the arch direction (arrow B in FIG. 2) while the cutter head is advanced (arrow A in FIG. 4). When the excavation for one arch has been completed, the self-propelled gantry can be advanced by one stage, and the above operation can be repeated again.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the illustrated embodiments. FIGS. 1 and 2 illustrate a case where a substantially semicircular large-section tunnel 10 having a diameter of, for example, about 20 to 30 m is excavated in hard rock or medium hard rock.

In this tunnel construction procedure, first, an advanced shaft 1,1 having a diameter of about 5.0 m in this embodiment is attached to a lower end on both sides of a tunnel 10 to be formed by a tunnel excavator 12 such as a tunnel boring machine. Excavate one pair (construction procedure). In the present embodiment, the advanced shaft 1 is excavated in the form of a preceding tunnel that precedes arch excavation by the arch excavator 20 described below, but may be formed in advance as a shaft that passes from the start side to the arrival side. Good. This advanced shaft 1
Inside, as shown in FIGS. 1 and 2,
A belt conveyor 14 is laid in the extension direction of the advanced shaft 1.

After the advanced shaft 1 is formed, as shown in FIG. 3, an H steel 18 is placed in the advanced shaft 1 and a rail 19 is laid thereon. The possible arch excavator 20 excavates the arch outer space 2 of the tunnel 10 (construction procedure).

As will be described in detail later, the arch machine 20 has an arch-shaped reaction force frame 21 that can run on the rail 19, and a small excavation having a diameter of, for example, about 2 m is provided on the front surface of the reaction force frame 21. Machine (small TBM) 24
There is a base or a plurality of bases (two in this example) as needed, which are arranged so as to be movable along the arch. , 2
9, the excavator 24 is shifted in the arch direction (arrow B in FIG. 2) while moving forward (arrow A in FIG. 4) while taking a reaction force, and if excavation for one arch is completed, 1 It is configured to advance forward in stages and repeat this again to excavate. The cutter head 23 of the excavator 24 is different from a normal cutter head, and has a structure in which a cutter is also provided on the side of the head.

The excavation by the arch excavator 20 is performed by the advanced shaft 1 excavated by the preceding tunnel excavator 12.
The excavation of the arch outer space 2 and the advanced shaft 1 can be performed in parallel. As the excavation by the arch machine 20 progresses, the lining concrete, that is, the arch concrete 3 is sprayed or cast in place using the slide center 42.
(Construction procedure). This arch concrete 3
Is less than or equal to the height of the arch outer peripheral space 2,
In the arch outer peripheral space 2, the remaining arch outer peripheral space 2 a remains inside the arch concrete 3. In the embodiment shown in FIG. 1, the lining concrete 3 is cast using the slide center 42 provided behind the excavator 24, and the excavator 24 is advanced through the slide center 42 and the reaction force receiver 13. When the reaction force is applied, the arch outer space 2
Obtained from the surrounding ground.

After the completion of the arch concrete 3, the remaining ground inside the arch concrete 3 is excavated by a whole cross section or a bench cut (construction procedure). Here, the excavation work of such a large cross section is performed, but since the advanced shaft 1 and the remaining arch outer peripheral space 2a are previously formed outside the cross section, these contribute as free surfaces, and are extremely easy and efficient. Can be drilled well. In addition, arch concrete 3
Enables safe and rapid excavation of large section tunnels and shortens the overall construction period. Further, the advanced shaft 1 can obtain ground information and can be used as a place for performing an auxiliary construction method in advance when a bad geology is encountered.

Next, a concrete construction method for forming the arch outer peripheral space 2 and the arch concrete 3 will be described.

First, the construction of the arch machine 20 for excavating the arch outer peripheral space 2 of the tunnel will be described. As can be seen from FIGS. 3 and 4, the arch machine 20 includes an outer steel shell 22a and an inner steel 22a. It has an arch-shaped reaction force frame 21 composed of a shell 22b (FIGS. 1 and 2), and can move on a rail 19 laid in the advanced shaft 1. In front of the space surrounded by the double steel shells 22a and 22b of the arch machine 20, two small excavators 24 each having a cutter head 23 having a diameter of about 2 m are arranged. The excavator guide 25 (FIG. 3) as a direction moving mechanism is configured to be able to move along the arch. Excavator 2
As shown in an enlarged manner in FIG. 5, a front body 24a having the cutter head 23, a middle body 24b which is a core part integrally formed with the front body 24a, and a rear body which accommodates the middle body 24b so as to be able to enter and exit. 24c and a hydraulic jack 2
7, the cutter head 23 serving as the front body is moved to the rear body 24c.
It is configured to extend and retract to move forward and backward.

In order to obtain a reaction force when the cutter head 23 is extended from the ground side, the reaction force frame 21 projects radially outward and inward from the peripheral surfaces of the outer steel shell 22a and the inner steel shell 22b. Grippers 28 and 29 (see FIG. 3) for obtaining a reaction force from the ground and a hydraulic jack (not shown) for driving the grippers 28 and 29 are provided.
, And the cutter head 23 is advanced to excavate while taking the reaction force from the ground in and out of the radial direction. The cutter head 23 is also provided with a blade on its side, so that excavation by moving in the direction of the arch is possible.

The reaction force frame 21 of the arch machine 20 is provided with a plurality of rock bolt drifters 30 and a plurality of sprayers 40, in addition to the excavator 24. That is, the reaction frame 21 has two zones of guide cells running in the arch circumferential direction so as to be continuous with the outer periphery thereof, that is, the guide cell 31 for the drifter and the guide cell 41 for the spraying machine shown in FIG. A drifter boom base 32 (FIG. 3) of the lock bolt drifter 30 is provided in the drifter guide cell 31 so as to be movable in the circumferential direction of the arch, and the blower guide cell 41 is blown. The attaching machine 40 is provided so as to be movable along the arch circumferential direction. FIG. 3 shows the lock bolt drifter 32a while the hole is being drilled and the lock bolt drifter 32a while the hole is being drilled.

Now, a concrete construction method using the arch machine 20 having such a configuration will be described with reference to FIG. In the embodiment of FIG. 4, the advanced shaft 1 is configured to pass from the start side to the arrival side.

(1) First, the reaction force frame 21 is moved toward the face, and the excavator 24 is pressed against the face 4.

(2) The reaction force frame 21 is fixed to the ground by the grippers 28 and 29. That is, the grippers 28 and 29 of the excavator 24 are pushed outward and inward in the radial direction of the arch, and a reaction force is obtained from the ground side when excavating in the next step.

(3) While the hydraulic jack 27 mounted on the excavator 24 is extended, the excavator 24 is
The outer peripheral portion of the tunnel is slid along the excavator guide 25, thereby performing excavation. The reaction force at this time is obtained from the ground side by the grippers 28 and 29 pushed outward and inward in the arch radial direction. In addition, the shear is carried out to the arrival side of the advanced shaft 1 by the belt conveyor 14 laid in the advanced shaft 1.

(4) When the hydraulic jack 27 is fully extended, excavation is stopped, the jack 27 is contracted, and the gripper 2
After subtracting 8, 29, the operation (1) is performed. That is,
The excavator 24 excavates by repeating the above operations (1) to (3). (5) During excavation, the rock bolt drifter 30 mounted on the reaction force frame 21 cuts as shown in FIG. The arch concrete 3 is obtained by piercing and rock bolting and spraying concrete by a spraying machine 40.

In the concrete lining portion, as shown in FIG. 1, a required concrete casting space is formed by the lining form and the toe form of the rear slide center 42, and the concrete 3 is cast. May be formed.

Thus, the arch outer peripheral space 2 is dug, the arch concrete 3 is formed on the outer layer in the arch outer peripheral space 2, and the space 2a is left on the inner layer. This is to provide a receiving arch concrete 3 on the ground side before excavating the ground 7 in the tunnel 10 to secure safety and to secure a free surface inside the arch concrete 3. Yes, its presence in the arch concrete 3 allows for safe and rapid excavation of large section tunnels, and the increase in free surface increases the efficiency of excavation.

[0031]

In summary, according to the present invention, the following excellent effects can be obtained.

(1) According to the first aspect of the present invention, after an advanced pit is preliminarily excavated on both sides below the tunnel cross section by a tunnel excavator, the excavator is slid in a ring-cut outer peripheral portion of the tunnel cross section. Since the excavation is performed while the excavation is being performed, the arch outer peripheral space of the large-section tunnel can be formed economically with a small number of excavators.

In addition, the advanced shaft can obtain ground information and can be used as a place for performing an auxiliary construction method in advance when a bad geology is encountered. Sliding can also be performed using this advanced shaft.

(2) According to the second aspect of the invention, the arch outer peripheral space is divided into an outer layer and an inner layer, and arch concrete is cast on the outer layer to form an outer shell, and the inner shell remains. The space around the arch remains. Therefore, when excavating the ground in the outer shell, the remaining arch outer peripheral space contributes as a free surface for facilitating excavation, while the outer layer exists as precedent arch concrete during excavation. Therefore, a large-section tunnel can be excavated safely and rapidly. Therefore, it is suitable for excavating rock tunnels with large cross sections.

(3) According to the arch excavator used in the first and second aspects of the present invention , the small excavator provided on the front of the arch-shaped self-propelled gantry moves along the arch. And the cutter head is capable of moving forward and backward, and the cutter head also has a cutter on the side of the head.
Therefore, it is possible to use such a method that the excavator is shifted in the arch direction while moving the cutter head forward by taking the reaction force from the ground side by the gripper, thereby forming the arch outer peripheral space portion of the large-section tunnel.

[Brief description of the drawings]

FIG. 1 is a view showing a cross section of a tunnel by a rock tunnel excavation method according to the present invention.

FIG. 2 is a schematic diagram showing a cross section of the tunnel of FIG.

FIG. 3 is a schematic front view showing an arch machine used in the present invention.

FIG. 4 is a view showing an embodiment in which an arch outer peripheral space and an arch concrete are formed by the rock tunnel excavation method of the present invention.

FIG. 5 is a view showing a portion of an excavator in the arch machine shown in FIG. 4;

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 advanced shaft 2 arch outer space 2a arch outer space 3 arch concrete 4 face 10 tunnel 12 tunnel excavator 14 belt conveyor 18 H steel 19 rail 20 arch excavator 21 reaction frame 22a outer steel shell 22b inner steel shell Reference Signs List 23 Cutter head 24 Excavator 24a Front trunk 24b Middle trunk (core) 24c Rear trunk 25 Excavator guide 27 Hydraulic jack 28, 29 Gripper 30 Lock bolt drifter 31 Drifter guide cell 32 Drifter boom table 40 Sprayer 41 Guide cell for spraying machine 42 Slide center

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) E21D 9/10

Claims (2)

(57) [Claims] An arc-shaped self-propelled gantry and a self-propelled gantry
Small size with multiple units slidably arranged along the arch on the front
An excavator, and a front-rearly mounted excavator
With a cutter head that also has a cutter on the side of the
With the gripper provided on the self-propelled platform to obtain from the ground side
A rock tunnel excavation method for forming a tunnel in the rock using an arch machine provided with the step of excavating an advanced shaft on both sides below the cross section of the arched tunnel, and forming an arch on the arched base. A step of forming an arch outer peripheral space by slidingly excavating an outer peripheral portion of a tunnel cross section in a ring cut shape by an arch excavator equipped with an excavator slidably along the arch excavator; Excavating the ground in the tunnel surrounded by the arch outer peripheral space as a rock tunnel excavation method. 2. An arch-shaped self-propelled gantry and a self-propelled gantry.
Small size with multiple units slidably arranged along the arch on the front
An excavator, and a front-rearly mounted excavator
With a cutter head that also has a cutter on the side of the
With the gripper provided on the self-propelled platform to obtain from the ground side
An excavation method of a rock tunnel for forming a tunnel in a rock using an arch excavator provided, the excavation of an advanced shaft by a tunnel excavator on both sides below an arched tunnel section, A step of forming an arch outer peripheral space by slidingly excavating an outer peripheral portion of a tunnel cross section in a ring-cut shape by an arch excavator equipped with an excavator slidably along an arch on a gantry. A step of forming an outer shell by casting arch concrete as an outer layer and leaving a remaining arch outer peripheral space in the inner layer, and thereafter leaving the remaining arch outer peripheral space as a free surface; Excavating the ground in the tunnel surrounded by the remaining arch outer peripheral space.