JPH09125867A - Tunnel excavation method - Google Patents

Abstract

(57) [Summary] [Purpose] An object of the present invention is to provide a tunnel excavation method that can eliminate noise and vibration, has high excavation efficiency, and can be applied to irregularly shaped tunnels. [Structure] A main groove 12a and a sub-groove 12 are formed on a bedrock 14 of a tunnel excavation surface 13 at predetermined intervals by a water jet 18.
Step b is performed to form a grid-shaped kerf 12, and a wedge-shaped breaking tool 16 is pryed into the kerf 12 to form a rock bed 1
4 is divided by the bottom portion to sequentially break it into blocks 15, and the folded blocks 15 are removed, and in the next step, the kerf 12 is formed again to sequentially excavate. In addition, the nozzle 1 that jets the water jet 18
7 is mounted on an arm type robot 19 having a self-propelled device 20, and the wedge-shaped destruction tool 16 is mounted on an earthmoving machine 22 having the self-propelled device 20.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tunnel excavation method for excavating rock mass on a tunnel excavation surface by mechanical digging without blasting, low noise.

[0002]

2. Description of the Related Art In tunnel excavation, for a long time, the method of drilling a hole in a rock mass with a chisel machine, loading dynamite into the hole, destroying it by blasting, and then excavating was the exclusive method. However, recently, there have been pollution problems such as noise, vibration and explosion sound caused by chisel rocks and blasting, and cracks in neighboring areas due to these, and in particular, there are many cases where the blasting method is prohibited. The machine digging method is adopted in.

In this mechanical digging method, a tunnel boring machine has been used when the cross section is constant and the tunnel is long, for example, in the case of a Seikan tunnel. However, when the tunnel cross section is irregular and the tunnel is long, a method is generally used in which a hole is first drilled with a chisel and the surrounding area is broken using this as a foothold.

[0004]

Specifically, in the expansion and destruction method using hydraulic equipment, the diameter of the hole that is the first step is 60 to 2 which is suitable for the hydraulic equipment into which the cone of the chisel rock machine is inserted.
You have to open a large hole of 00 mm. By the way, it is 40 to 60 mm in blasting. In addition, the expansion and destruction method cannot solve the problems of noise and vibration. further,
From the aspect of rock mass destruction, even if the hydraulic equipment is expanded,
If the only foothold is a hole, the bedrock is strongly restrained, cracks are less likely to occur, and it is often difficult to destroy it.

The problem of noise and vibration can be solved by a method of excavating only with a water jet instead of the mechanical digging method. However, the drilling efficiency itself is extremely low, and it is far from practical use. That is, even if a large horsepower device is used, the excavation efficiency does not reach that of mechanical excavation. However, the rocks that are left untouched on the ground are not free of human hands and are all free surfaces, so masonry should search for appropriate joints (potential cracks). It is well known in the work of quarrying stones and tombstones that it can be easily cracked just by digging with a chisel or a wedge.

From these facts, the bedrock is hard to break even if it is pushed out from the center in eight directions, but one is in the air (free surface).
In case of, it can be easily destroyed by tapping the chisel or wedge lightly. This clearly shows the characteristic that it is strong against compression but weak against bending and shearing.

It is an object of the present invention to provide a tunnel excavation method which can eliminate noise and vibration, has high excavation efficiency, and can be applied to an irregularly shaped tunnel.

[0008]

SUMMARY OF THE INVENTION According to the present invention, a step of forming a large number of kerfs 12 at a predetermined depth in a rock 14 of a tunnel excavation surface 13 with a super-high pressure water jet 18, and a wedge-shaped groove 12 is formed. Put the destruction tool 16 into the bedrock 1
In the step of forming a large number of kerfs 12, the main grooves 12a are formed at predetermined intervals, and the sub-grooves 12b that are substantially orthogonal to the main grooves 12a are formed to form a grid pattern. Further, the nozzle 17 for injecting the water jet 18 is mounted on an arm type robot 19 having a self-propelled device 20, and the wedge-shaped destruction tool 16 is mounted on the self-propelled device 20.
It is a method of excavating a tunnel mounted on the excavating machine 22 for earthwork having the above.

[0009]

[Action]

First step: a step of forming the kerf 12 The kerf 12 is formed on the bedrock 14 of the tunnel excavation surface 13 by the water jet 18. This kerf 12
For example, the main groove 12a and the sub groove 12b are cut in a grid pattern. Second step: a step of breaking the bedrock 14 into blocks When the wedge-shaped breaking tool 16 is driven into the kerf 12, the bottom of the bedrock 14 is easily broken, and the block 1
It becomes 5 and is sequentially folded. If there is no latent joint in the bedrock 14, the rock 14 is broken at the root portion where the maximum bending generated by driving the breaking tool 16 acts. The third step: to be removed Block 1 which is sequentially destroyed by the destruction tool 16 and folded
By removing 5, the part of the bedrock 14 cut by the water jet 18 is beautifully destroyed. Then
In the next step, the kerf 12 is formed again and the excavation is sequentially performed.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the tunnel excavation method according to the present invention will be described with reference to FIG. First step: a step of forming the kerf 12 The kerf 12 is formed by the water jet 18 on the bedrock 14 of the tunnel excavation surface 13 as shown in FIG. 1.
As shown in FIG. 2A, the kerf 12 is formed by forming a large number of main grooves 12a, which are lateral grooves, with a predetermined width, a predetermined depth, and a predetermined interval. The main groove 12a is for dividing the bedrock 14 into blocks, and the groove pitch is selected to an appropriate value depending on the strength of the bedrock 14.

Further, if necessary, a sub groove 12 formed of a vertical groove.
Similarly, a large number of b are formed with a predetermined width, a predetermined depth, and a predetermined interval. The sub groove 12b is for facilitating the division into blocks, and can be omitted in some cases. In the example of FIG. 1, the kerf 12 includes the main groove 12 a and the sub groove 1.
Although the grooves are cut in a grid pattern with 2b, the invention is not limited to this, and may be a combination of radial grooves from the center and ring-shaped grooves having different diameters with the center as a fulcrum. May be grooves of irregular shape or spacing. Further, the main groove 12a may be a vertical groove and the sub groove 12b may be a horizontal groove.

The depth of the kerf 12 is set by controlling the discharge amount, discharge pressure, and traveling speed of the water jet 18, and various conditions such as hardness and properties of the bedrock 14 are set in addition to these conditions. Since it depends on the condition, the bedrock 14 may be actually cut and decided. When not using the trial cutting, a needle-shaped ruler may be inserted on the side of the water jet 18, or the kerf 12 may be dug while having a depth sensor for reflecting ultrasonic waves.

Second Step: Step of Breaking Rock Mass 14 into Blocks As shown in FIG. 2B, a wedge-shaped breaking tool 16 is driven into the kerf 12 cut in the rock mass 14. Then, the bottom part of the bedrock 14 is easily broken, and the block 1
It becomes 5 and is sequentially folded. If there is no latent joint in the bedrock 14, the rock 14 is broken at the root portion where the maximum bending generated by driving the breaking tool 16 acts. If bedrock 1
If there is a latent joint in No. 4, the joint is destroyed at the joint, but the remaining portion is driven by the destruction tool 16 again or left as it is, and in the next step the kerf 12 by the water jet 18 Formation is repeated.

Third step: to be removed Block 1 which is sequentially broken by the breaking tool 16 and folded
By removing 5, the part of the bedrock 14 cut by the water jet 18 is beautifully destroyed. Then
In the next step, the kerf 12 is formed again as shown in FIG.

Next, the excavation speed will be described by way of a concrete example. Calculation conditions (1) The excavation surface 13 of the tunnel is the bottom surface 1 of the tunnel.
The height from 1 to the top of the tunnel excavation periphery 10 is 6 m, and the left and right width of the tunnel excavation periphery 10 is 8 m. (2) Water jet 18 at 1000 horsepower, 25
The pressure is set to 00 kgf / cm ² × 100 liter / min. (3) The strength of the bedrock 14 is made equal to that of the slab concrete.

Grooving speed By the above (1) and (2), width 10 mm x depth 30 cm x
It is set to 300 to 400 cm / min.

The total length of the kerfs 12 The pitch of the main grooves 12a is 30c, which is the same as the groove depth, assuming that the folded block 15 can be broken up to a substantially square shape.
The pitch of the sub-grooves 12b is about 4 times the pitch of the main grooves 12a. Therefore, the height of the main groove 12a is 6 m ÷
0.3 m × length 8 m = 160 m The sub-groove 12b has a length of 6 m × width 8 m / 1.2 m = 40 m
Becomes

From the above, the number of folded blocks 15 is 20 grooves × 7 grooves = 140.

Time required (1) Net grooving time T1 T1 = 200 m / 3.0 to 4.0 m / min = 50 to 6
7 min (2) Divided time of the net folded block 15 T2 T2 = 140 pieces / 2 pieces × 15 to 20 s = 50 to 67 mi
n (3) Work efficiency (net operating time rate) When η = 0.7, T3 = (50 to 67 + 18 to 23) ÷ 0.7 = 97 to 1
With a depth of 29 min or more, per depth of 30 cm (per 14.4 m ³ ) 9
It takes 7 to 129 minutes, and in 12 hours a day, 1.
It becomes 6 to 2.2 m (80 to 107 m ³ ).

Next, an apparatus used in the breaking method of the present invention will be described with reference to FIGS. 3, 4 and 5. FIG. 3 shows a machine for operating the nozzle 17, and when the grooving accuracy is not so required, a normal arm type construction machine can be used. Further, in order to efficiently perform grooving, the arm type robot 19 attached to the self-propelled device 20 is used.

To the nozzle 17, a 1000-hp class water jet generator 21 for obtaining super-high pressure water is connected via a super-high pressure water hose 43. This water jet generator 21, as shown in FIG.
It is composed of a hydraulic pump 40, a pressure booster 41, and an accumulator 32. The hydraulic pump 40 alternately sends pressure oil to the first cylinder chamber 26 and the second cylinder chamber 27 of the pressure booster 41 to alternately reciprocate the piston 23 to move the piston 2
Water in the first compression chamber 28 and the second compression chamber 29 is pressurized by the first piston rod 24 and the second piston rod 25, which are integral with the unit 3, respectively, from the first ultra-high pressure output port 30 and the second ultra-high pressure output port 31, respectively. Outputs ultra-high pressure pressurized water.

The pressurized water alternately sent from the first ultra-high pressure output port 30 and the second ultra-high pressure output port 31 removes the pulsating flow by the accumulator 32 and sends it to the fresh water nozzle 33 or the abrasive nozzle 36. The fresh water nozzle 33 is for obtaining the water jet 18 of only water, and outputs the water jet after being narrowed by the orifice 34. The abrasive nozzle 36 is for cutting the rebar as well, and after squeezing with the orifice 38, the abrasive is injected from the abrasive inlet 37 and output as an abrasive jet 39 containing the abrasive.

The wedge-shaped breaking tool 16 is usually used by an earthworking excavating machine 22 such as a backhoe as shown in FIG. 4 in order to strongly push the wedge-shaped breaking tool 16 into the kerf 12 of the bedrock 14. This earthmoving machine 2
2 is mounted on the self-propelled device 20. In this case, when the electromagnetic vibrator is attached to the base of the wedge-shaped breaking tool 16, the broken block 15 can be operated with high efficiency as if it were broken by a breaker.

With the above-described device, while controlling the traveling direction of the tunnel excavation surface 13 by operating the self-propelled device 20 and the arm type robot 19, the groove 12 shown in FIGS. The wedge-shaped breaking tool 16 is pushed into the kerf 12 of the bedrock 14 by the operation of the excavating machine 22 for breaking.

In the above embodiment, the main grooves 12a and the sub-grooves 12b of the kerf 12 formed in the bedrock 14 are formed at the same groove pitch, but when the characteristics of the bedrock 14 change in the middle, The groove pitch may be narrower in the hard portion than in the soft portion. In addition, when slicing with the water jet 18 of the clean water slur 33 is insufficient or impossible, shaving with the abrasive jet 39 of the abrasive slur 36 may be performed.

[0026]

【The invention's effect】

(1) The conventional chisel rock machine and the construction method by blasting have caused pollution problems such as noise, vibration, and explosion sound, and cracks in the neighborhood caused by these noises. With the method, noise and vibration can be eliminated.

(2) According to the method of the present invention, instead of excavating the tunnel excavation surface 13 entirely by the water jet 18, only grooving is performed by the water jet 18.
After that, the wedge-shaped breaking tool 16 breaks the block 15, so that the efficiency is extremely high. By the way, 3
When grooving with a width of 10 mm at a pitch of 0 cm, the entire surface can be excavated at a speed 30 times faster than when excavating with a water jet 18.

(3) According to the method of the present invention, the folded block 15 which is grooved in a grid pattern has five free surfaces except for the surface adhering to the bedrock 14 in the excavation direction.
It can be easily broken and removed by the wedge-shaped breaking tool 16, and the efficiency of the entire excavation is high.

(4) The method according to the present invention can be applied to both the cross-sectional direction of the tunnel excavation surface 13 and the direction of the surrounding wall surface. Therefore, the method according to the present invention can also be applied to the excavation of an irregularly short tunnel excavation surface 13 or a basement. .

[Brief description of the drawings]

FIG. 1 is an explanatory view showing an example of a groove cutting state of a tunnel excavation surface 13 for explaining a tunnel excavation method according to the present invention.

2A is a sectional view showing a state in which a kerf 12 in FIG. 1 is formed, and FIG. 2B is a sectional view showing a state in which a block 15 is broken.

3 is a perspective view of a water jet generator 21 for implementing the method according to the invention.

FIG. 4 is a perspective view showing an attached state of the wedge-shaped breaking tool 16 for realizing the method according to the present invention.

5 is a water jet generator 40 shown in FIG.
FIG.

[Explanation of symbols]

10 ... around excavation of tunnel, 11 ... bottom of tunnel, 1
2 ... Cutting groove, 12a ... Main groove, 12b ... Sub groove, 13 ... Tunnel excavation surface, 14 ... Rock bed, 15 ... Folded block, 16 ... Wedge-like destruction tool, 17 ... Nozzle, 18 ... Water jet, 19 ... Arm type robot, 20 ... Self-propelled device, 21 ... Water jet generator, 22 ... Earthmoving excavator, 23 ... Piston, 24 ... First piston rod, 25 ... Second piston rod, 26 ... First cylinder chamber, 27 ... 2nd cylinder chamber, 28 ... 1st compression chamber, 29 ...
2nd compression chamber, 30 ... 1st super high pressure output port, 31 ... 2nd super high pressure output port, 32 ... Accumulator, 33 ... Shimizu nozzle,
34 ... Orifice, 36 ... Abrasive nozzle, 37 ... Abrasive inlet, 38 ... Orifice, 39 ... Abrasive jet, 40 ... Hydraulic pump, 41 ... Booster, 42 ... Cylinder, 43 ... Super high pressure hose.

Claims (4)

[Claims] 1. A large number of kerfs 1 are formed in a rock 14 of a tunnel excavation surface 13 at a predetermined depth by an ultrahigh pressure water jet 18.
2. A method of excavating a tunnel, which comprises the steps of forming 2 and a step of sequentially breaking the rock 14 by prying a wedge-shaped breaking tool 16 into the kerf 12. 2. The method for excavating a tunnel according to claim 1, wherein the step of forming a large number of kerfs 12 comprises forming main grooves 12a at predetermined intervals. 3. The step of forming a large number of kerfs 12 is carried out by forming main grooves 12a at predetermined intervals and forming sub-grooves 12b which are substantially orthogonal to the main grooves 12a to form a grid pattern. The tunnel excavation method described in 1. 4. A nozzle 17 for jetting a water jet 18 has an arm type robot 19 having a self-propelled device 20.
The method for excavating a tunnel according to claim 1, 2 or 3, wherein the wedge-shaped breaking tool 16 is mounted on an earthmoving machine 22 having a self-propelled device 20.