JPH01131781A - Method of forming groove to base rock - Google Patents

Abstract

PURPOSE: To make a device small-sized, and form a groove easily, accurately, and efficiently, by previously generating a crack or a streak on a rock-bed by a preceding crushing device using high pressure jet water or the like. CONSTITUTION: A preceding crushing device 14 and an excavating device 15 which are built in a frame 6 for the excavating device and are respectively movable in the upper and low direction by hydraulic cylinders 16, 17, are held with a supporting frame 13 guiding their movement. The frame 6 is applied to the facing part of a trench 2, and while ejecting high pressure jet water by the jet nozzle provided on the device 14, a crack or a streak are generated from the bottom part of the trench 2 in order upward by the device 14. When the device 14 is further sufficiently elevated, the excavating cutter 18 of the device 15 is extended to excavate a place on the same locus of the crack or the streak made by the device 14, and it is repeated to form the desired trench 2.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is directed to the trenches formed in the bedrock (i.e., the following description This invention relates to a method for forming grooves in rock that can be accurately and effectively constructed (referred to as trenches).

[Prior art]

The most commonly used mechanical device for forming trenches on land is a shovel-type excavator, a so-called backhoe.

As shown in Fig. 5, this mechanical device has a shovel 32 attached to the tip of a tiltable pedestal 31 installed on a traveling device 3 (such as a vehicle), and excavates and transports earth and sand 33 by digging it in from the front. , Trench on land 2
The #J& machine used for formation is extremely rational and efficient.

However, since the shovel-type excavator pushes the tip of the shovel 32 into the earth and sand 33 to be excavated and shear-breaks the earth and sand exclusively by the horizontal excavation force, the shear lFr strength or compressive strength of the earth and sand 33 to be excavated is There is a problem in that as the amount of excavation increases, the excavation capacity rapidly decreases, and eventually it becomes impossible to excavate.

On the other hand, excavators conventionally used for excavating rock, etc. have rotating cutter heads, and there are two types: one that compresses and crushes the rock by the thrust of the cutter, and the other that cuts with a cutter bite. Although it is used for excavating trenches, there are no actual examples of it being used to form trenches.

Therefore, at present, there is no specialized machine for forming trenches in rock on land, and when this is necessary, the rock is crushed using blasting, rock breaker-1 drilling, etc., and excavated using excavators. There is a way to remove it by machine etc.

It is used.

However, all of these crushing methods are inefficient, and the cross-sectional shape of the trench becomes inaccurate, making it necessary to crush and excavate the rock to an extra size, which is uneconomical.

In addition, since the rock is crushed by impact, there is a risk that it may affect other structures, and construction may not be possible depending on the surrounding conditions.

On the other hand, a commonly used method for forming trenches on the water bottom is to use a grab dredger, and as shown in FIG. Corresponding part of earth and sand () 3
This is a method of directly excavating and removing.

The grab type dredger has fewer restrictions on water depth, and it is possible to increase the excavation force by increasing its own weight relative to the capacity of the grab bucket 34, so it can handle up to a certain degree of hard soil.

However, as shown in FIG. 6, the position of the barge 8 and the position of the grab bucket 34 suspended by the wire 36 are inaccurate, and the excavation cross section of the trench 2 becomes very large, compared to the required cross section. However, there is a problem in that extremely excess soil must be dredged.

In addition, it is almost impossible to excavate bedrock with a grab-type dredger, so in this case, the rock is crushed using a rock crusher, etc., and then removed using a grub-type dredger, etc. method is used.

The rock crushing ship has a structure as shown in FIG. 7, and a weight 38 called a rock crushing bar is dropped from a barge 8 to crush rock l by its impact force.

Therefore, in this case as well, the barge 8
, as well as the position of the weight 38 suspended by the wire 36, and a very large excess of rock l for the required section must be crushed and dredged.

In addition, if there are other structures that cause the rock mass 1 to be crushed by the impact of the weight 38, there will be restrictions on the impact on those structures, and in some cases, construction may not be possible.

On the other hand, the preconditions for forming grooves, or trenches, in rock are:
The objective is to develop an excavation method that can easily and efficiently excavate the rock.

For this purpose, the most effective method is to use a rotary cutter head, which has traditionally been considered effective for excavating rock.

However, since the rotary cutter head crushes the rock by the thrust of the cutter or cuts the rock by the cutter bite as described above, the torque and reaction force required for excavation are extremely large.

Therefore, when using this for trench excavation in rock, the cutter head drive device, support for holding reaction force, and traveling device are also large, resulting in an excavation structure that is extremely unsuitable for excavating a long and narrow cross section like a trench. There is a high possibility that it will become an opportunity.

One way to fracture rock is to directly destroy it using impact force or excavation force, but another way of thinking is to crush it by other suitable methods before excavating or crushing it. Alternatively, there is a method called advance crushing, in which the force required for subsequent excavation or crushing is reduced by pre-treating the material to make it easier to crush.

An example of this is the method of crushing the rock using a weight or the like before excavating with a grab-type dredger when forming a trench on the bottom of the water. One of the methods is to use high-pressure water jets.

Today, the technology of cutting objects using high-pressure water jets is widespread (
It has been put into practical use, especially for rock excavation. Prior to excavation or crushing, high-pressure water jets reaching several thousand atmospheres are used to create cracks or streaks in the rock, thereby making subsequent excavation or crushing easier. This has already been carried out in some cases, and it is known that high-pressure water is injected from a nozzle onto the bedrock in the invention of JP-A-58-80036 relating to a rock dredging method and device.

Additionally, in addition to high-pressure jet water, there are other technologies that use electromagnetic waves and fire jets to create cracks or streaks in bedrock in advance, but these are being tested on a trial basis but are still at the stage of practical use. This has not yet been achieved.

Therefore, the inventors of the present invention came up with the idea that an accurate trench could be effectively formed in the rock by using a drilling device such as the above-mentioned rotary cutter head in combination with high-pressure water jet. As a result of adding the above, this invention was achieved.

[Purpose of the invention]

The present invention was made in order to solve the above-mentioned problems in forming trenches on land and on the bottom of the water, and it is possible to form trenches with high accuracy and effectively in rock formations on land and on the bottom of the water. The purpose is to provide a method for forming grooves in rock that makes it possible to

[Structure of the invention]

In order to achieve the above object, the method of forming grooves in rock according to the present invention involves sequentially injecting high-pressure water from an injection nozzle or the like from below upwards onto the part of the rock on land or underwater where grooves are to be formed. This method is characterized by excavating on the same trajectory with an excavating device such as an excavating cutter, following the preceding crushing that crushes the part of the rock where the groove is to be formed.

When laying pipes, electric wires, and other buried objects on land or underwater, these buried objects are at most several tens of centimeters thick, so a trench width of 1 to 2 meters is sufficient. Also, its depth is about several meters.

When forming a trench with a long and slender cross-section, it is natural to assume that the excavation trajectory of the excavator is vertical. By running a pre-crushing device that uses high-pressure water injection, etc. on the same trajectory as the excavator, it is possible to effectively combine the pre-crushing work and the subsequent excavation work, and the idea of the present invention is to On this point.

That is, by creating cracks or striations in the rock using a preliminary crushing device that uses high-pressure water jets that can cover an appropriate width depending on the cross section of the trench to be formed, subsequent excavation by the excavating device is facilitated. The greatest feature of the present invention is that the excavation device follows the preceding crushing and excavates on the same trajectory.

By specifying the trajectory of the preceding crushing device and having the excavation device run on the same trajectory, it is possible to limit the excavation cross section, which makes it possible to improve the accuracy of the excavation cross section of the trench. Become.

In addition, by drilling after creating cracks or streaks in the rock using high-pressure water jets, the drilling torque required of the excavator is significantly reduced, making it possible to downsize the excavator. Since the excavation reaction force exerted on the support device during excavation is also reduced, the support device itself can be downsized.

〔Example〕

The method of the present invention will be explained below with reference to the drawings.
First, Fig. 3-A is a front view of Example 1 in which the method of the present invention is applied to trench formation on land, and Fig. 3-B is a side view thereof. A traveling device 3 is stopped on a bedrock l, straddling a trench 2.

The traveling device 3, which has sufficient weight to absorb the excavation reaction force generated by excavating the rock mass 1, has an excavation device mount 6 incorporating a preceding crushing device and an excavation device, which is capable of holding and tilting the traveling device 3. It is attached via a hydraulic cylinder 5 for the purpose of tilting the holding and tilting pedestal 4 and the excavation equipment pedestal 6.

As will be described later, a preceding crushing device and an excavation device are incorporated into the excavation device mount 6.

As shown in Fig. 3-B, the excavator mount 6 is positioned at the cutting edge of the trench 2 to be excavated by the traveling device 3 and the holding and tilting mount 4, and when the predetermined excavation is completed, the traveling device 3 to start the next excavation, and in this way, the predetermined trench excavation work is continued one after another.

Figure 4-A is a front view of Example 2 in which a similar device is used to form a trench on the bottom of the water, and Figure 4-B is a side view of Figure 4-A.

In the side view, a barge 8 is stopped on the water surface by lifting legs 9, straddling a trench 2 formed in a bedrock 1 existing at the bottom of an underwater body 7.

The barge 8, which is held above the water surface by lifting legs 9 and has sufficient weight to absorb the excavation reaction force generated by excavating the rock mass 1, includes an excavation rig mount 6 that incorporates a preceding crushing device and an excavation device. However, the holding and tilting frame 4 that can hold and tilt the excavation equipment, the hydraulic cylinder 5 for tilting the excavation equipment, and the holding and tilting frame 4 are moved from the barge 8 using a lifting winch 12 and a lifting wire 11. It is attached via an inclined ladder 10 for approaching near the bottom of the water.

In Fig. 4-B, the excavator mount 6 located at the cutting edge portion is moved forward by changing the inclination angle of the inclined ladder 10 when a predetermined excavation is completed, and the inclination angle of the inclined ladder IO is changed. In some cases, when the next cutting edge cannot be reached, the barge 8 and the lifting legs 9 are moved forward to continue the predetermined trench excavation work.

Next, 2° Fig. 1-A, Fig. 1-B, and Fig. 1-C show an example of the preceding crushing device and the excavating device incorporated inside the excavating device mount 6 of the embodiments 1 and 2. It is something.

Figure 1-A shows the stage in which the excavation equipment stand 6 is applied to the cutting edge of the trench 2 to be excavated, and the rock mass is pre-crushed from the bottom of the trench 2 by the pre-crushing device ■4. At this stage, the advance crushing device 14 is located at the lower end of the excavation rig mount 6 and moves upward sequentially as the advance crushing progresses.
5 is stored inside the excavation equipment mount 6.

Figure 1-B shows that the preliminary crushing is progressing and the drilling rig 15
This shows a stage in which the advance crushing device 14 has risen sufficiently above that it does not get in the way of excavating the cut. While pushing out to the blade, that is, bedrock 1,
The entire excavation device 15 is sequentially moved upward to continue the excavation work to form the necessary trench 2.

Figure 1-C shows the final stage of trench excavation, in which the advance crushing device 14 that has reached the upper surface of the rock z1 in which the trench 2 is to be formed stops the preliminary crushing operation, and the excavator 15 moves the upper end of the cutting blade. Excavation continues.

In the figure, an excavator pedestal 6 placed against a bedrock l is surrounded by a support frame 13 on the outside.

The support frame 13 has the function of holding the preceding crushing device 14 and the excavating device 15 incorporated in the excavating device mount 6, and at the same time guiding them against vertical movement.

The advance crushing device 14, which is held by the support frame 13 and guided for vertical movement, is moved in the vertical direction by a hydraulic cylinder 16 for raising and lowering the advance crusher attached to the support frame 13.

In FIG. 1-A, the excavating device 15 located behind the preceding crushing device 14 has a support frame 1 similar to the preceding crushing device I4.
3 and is guided against vertical movement, and is moved vertically by a hydraulic cylinder 17 for lifting and lowering the excavating device attached to the support frame 13.

Inside the excavation device 15, there are an excavation cutter 18, an excavation cutter driving prime mover 19, and an excavator pushing hydraulic cylinder 2 for pushing these 18.19 forward.
0 is equipped.

As mentioned above, in FIG. 1-A, the advance crushing device 14 is located at the lower end of the support frame 13, and the trench 2 is
A new cutting blade at the bottom is to be pre-crushed, but at this stage the excavator 15 is located behind the pre-crushing device 14 because the hydraulic cylinder 20 for pushing out the excavator is in the retracted state.

FIG. 1-B shows the interior of the excavating apparatus 15 at a stage when the preceding crushing apparatus 14 has been sequentially moved upward by the hydraulic cylinder 16 for lifting and lowering the preceding crushing apparatus to a position where it does not interfere with the extrusion of the excavating apparatus 15. The excavation cutter 18 and excavation cutter driving prime mover 19 installed in the excavator are pushed out by an excavator pushing hydraulic cylinder 20 to a position where they directly excavate the rock mass 1 in front of the support frame 13, and are used to lift and lower the advance crushing device. The excavation rig 15, which follows the preceding crushing bag rf114, which is moved upward by the hydraulic cylinder 16, while maintaining an appropriate distance, continues to move upward by the hydraulic cylinder 17 for lifting and lowering the excavation rig.

When the excavation work is completed in the final stage of trench excavation shown in FIG.
The prime mover 19 for driving an excavating cutter is housed inside the excavating device 15 by a hydraulic cylinder 20 for pushing out the excavating device, and a hydraulic cylinder 17 for lifting and lowering the excavating device.
is lowered to the lower end of the support frame 13.

Further, the preceding crushing device 14 is also lowered to the lower end of the support frame IS by the hydraulic cylinder 16 for lifting and lowering the preceding crushing device, and the first
-The positional relationship is as shown in Figure A.

When the excavation work of trench 2 is completed by performing the series of operations shown in Figures 1-A, 1-B, and 1-C, as shown in Figures 3-A and 4-A, , 3rd-
In figure A, the traveling device 3 is moved forward and the
In the figure, by changing the inclination angle of the inclined ladder 10, the excavator mount 6 is brought into contact with the next cutting edge, and the preliminary crushing and excavation operations necessary for forming the trench 2 are successively continued.

Next, Figure 2 shows a preliminary crushing device 14 that uses high-pressure water injection.
This shows an example of this.

In Fig. 2, hydraulic cylinder 16 for raising and lowering the preceding crushing device.
A plurality of nozzles 21 for injecting high-pressure water are installed in the advance crushing device 14 which is raised and lowered by the pump, and a plurality of nozzles 21 for injecting high-pressure water are installed as necessary. 23 are connected.

The high-pressure jet water jetted from the high-pressure jet water jet nozzle 21 destroys the surface of the rock mass 1 in front of it due to its pressure, and by continuously jetting the high-pressure jet water, it moves inward from the surface of the rock mass 1. Cracks or streaks develop one after another, producing the so-called advance crushing effect that facilitates subsequent excavation by the excavation cutter 18.

〔Effect of the invention〕

As explained above, the method of forming trenches in rock according to the present invention differs from conventional trench forming methods in which rock is directly crushed using a crusher, blasting, etc. Since excavation is carried out after crushing in advance, it has the following advantages.

(b) Since excavation is performed after creating cracks or striations in the rock mass using a pre-crushing device that uses high-pressure water jets, etc., the required excavation force and excavation reaction force of the excavation device can be significantly reduced. This makes it possible to reduce the weight and size of the excavation equipment and the equipment for holding and moving the excavation equipment, and at the same time, it becomes possible to excavate hard rock, which was considered difficult with conventional excavation equipment.

(b) By reducing the weight and size of the excavation equipment in this way, it becomes possible to incorporate the entire excavation equipment into the excavation equipment mount, which allows the excavation equipment to come into contact with the cutting edge of the rock to be excavated for the first time. becomes possible.

(c) Both preliminary crushing and subsequent excavation using high-pressure water injection etc. are impactful to the target rock mass.
Since there is no need to apply a single layer, there is no effect on other structures, so even if there are structures around the excavation area of the trench, it is possible to form a trench with peace of mind. .

(d) Since the advance crushing device and the excavation device move up and down on the same trajectory using the support frame as a guide, accurate advance crushing and excavation are possible, and therefore the cross section of the trench can be formed accurately.

This also allows economical and quick trench shaping without the need for extra excavation as would be the case with conventional crushers or methods such as blasting.

Although the present invention relates to a trench forming method, the field of application of the method made possible by the combination of advance crushing and excavation is extremely wide, and it can be applied to various fields such as tunnel excavation, dismantling and removal of concrete structures, etc. It is possible to apply the basic technology of the present invention to

[Brief explanation of the drawing]

Figures 1-A, 1-B, and 1-C are illustrations of a preliminary crushing device and an excavating device installed inside a stand for an excavating device that forms grooves in rock using the method of the present invention. A series of explanatory diagrams showing the positional relationship between the advance crushing device and the excavation device at each stage of the trench formation work in the example, and Figure 2 is an implementation of the advance crusher using high-pressure water injection shown in Figure 1-A. FIG. 3-A is an explanatory perspective view of Example 1, and FIG. 3-B is an explanatory front view of Example 1 when the method of the present invention is used to form a trench on land. Side view, 4th
Figure -A is a front view of the explanatory view of Example 2 when the method of the present invention is used to form a trench on the bottom of water, Figure 4-B is a side view of Figure 4-A, Figures 5 and 6. FIG. 7 and FIG. 7 are explanatory diagrams showing application examples of different conventional trench forming methods, respectively. l...Rock, 2...Trench, 14...Advance crushing device, 15...Drilling device, 18...Drilling cutter, 21...Injection nozzle. Agent Patent Attorney Nobuo Ogawa −

Claims (1)

[Claims] High-pressure jet water is sequentially injected from below to above into the area where a groove is to be formed in the rock, following the previous crushing that fractures the rock in the area where the groove is to be formed, and excavation is carried out on the same trajectory. A method of forming grooves in rock that is excavated by equipment.