JP2909014B2 - Method for drilling earth and sand layer and rock and apparatus for drilling earth and sand layer and rock - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for continuously drilling a soil layer and a bedrock.

[0002]

2. Description of the Related Art Conventionally, Japanese Patent Publication No. Hei 7-91930 and Japanese Patent Publication No. Hei 7-91931 have been known as a device for drilling rock. This device is provided with a down hammer for rock cutting by vertical movement at a lower end of a rotating shaft, and fluid is ejected from a lower end of the down hammer.

[0003] In the above-described apparatus, the down hammer is operated while rotating the rotating shaft to excavate the earth and sand layer, and when the rock reaches the rock, the rock is excavated and the rock is excavated by the down hammer. ing. In the above-mentioned conventional example, the diameter of the hole to be excavated is the same as that of the down hammer.

[0004]

However, in the above-mentioned conventional example, since the excavation is performed while rotating the rotating shaft and operating the down hammer in the earth and sand layer, the earth and sand layer is excavated. There is a problem that it takes time to excavate. In other words, the down hammer is suitable for digging rocks by driving up and down, but when excavating while driving the down hammer up and down in the earth and sand layer, the down hammer moves up and down and the earth and sand tightens, and the down hammer Hinders digging. Moreover, in the conventional example, since the diameter of the down hammer is the same as the diameter of the hole to be excavated, it takes more time to excavate the earth and sand layer, and further, the diameter of the down hammer becomes larger. Therefore, the excavation of the above-mentioned earth and sand layer becomes slow, so that a down hammer having a large diameter is difficult to apply to actual construction, and as a result, there is a problem that it is difficult to form a large diameter hole.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and has been developed in consideration of the above problem. A main object of the present invention is to provide a method and an apparatus for drilling rock and a column body in which a soil and a consolidation liquid that penetrate an earth and sand layer and reach a part of the rock and a consolidation liquid are mixed and hardened. Walls and earth retaining walls can be formed and ground improvement can be performed, and when a horizontal force such as an earthquake is applied, a sediment layer that can absorb the horizontal force and a column that reaches a part of the bedrock, Another object of the present invention is to provide a method and an apparatus for drilling a soil and a bedrock which can form an underground wall and a retaining wall and improve the ground.

[0006]

SUMMARY OF THE INVENTION A method of drilling a sediment layer and a bedrock according to the present invention has a function of injecting a fluid at a high pressure downward from the tip and a downhammer for drilling a bedrock 4 by vertical movement. Upon drilling to bedrock 4 following below the soil layer 3 and the soil layer 3 by a device provided with a rotary drill bit 2 for cutting rock for drilling by the rotation diameter larger and than said down hammer 1 to 1 of the upper, down Hammer 1
Gas injection hole 8a for injecting high pressure gas at high pressure
And a liquid ejecting hole 8b for ejecting the liquid at a high pressure,
In excavation of the earth and sand layer 3, the liquid is ejected from the tip of the down hammer 1 at a high pressure while drilling and excavating below the down hammer 1 and excavating the earth and sand layer 3 above the down hammer 1 by rotating the rock drilling drill bit 2. And
Daunhan from the tip down the hammer 1 reaches the bedrock 4
The down hammer 1 is moved up and down while high- pressure gas used for vertically driving the hammer 1 is ejected at a high pressure to rock the rock 4 to a small diameter, and the rock that has been cut to a small diameter by the down hammer 1 rotates. It is characterized in that a large diameter is drilled by the rotary drilling bit 2 for drilling. By doing so, when excavating the earth and sand layer 3, the earth and sand layer 3 below the down hammer 1 can be inserted without resistance by loosening the earth and sand layer 3 in advance with a liquid that is jetted at a high pressure.
Moreover, since the down hammer 1 has a smaller diameter than the hole to be formed, the down hammer 1 can be further inserted into the earth and sand layer 3 without resistance, and the rotary drill bit 2 for rock drilling can be used.
Is a large-diameter liquid that has been injected at high pressure while rotating.
It is to excavate the soil layer 3 loosened by the body . Then, when reaching the bedrock 4, the down hammer 1 is driven up and down.
The down hammer 1 is driven up and down while ejecting the high-pressure gas used for drilling the rock 4 to drill a small diameter by the down hammer 1, and then a large diameter rotary drill bit for rock drilling is formed around the hole. A hole is drilled into a large-diameter hole by 2 rotations. By doing so, the excavated earth and sand and the liquid are stirred and mixed.
A combined pillar can be formed. Also, when drilling rock 4
Is the high pressure air used to drive the down hammer 1 up and down.
Drilling prior to drilling the rock 4 using the body
Blow out the powder to make the down hammer 1 easier to dig
be able to. Also, in this case, the liquid and the gas simultaneously
When sprayed, the down hammer 1 and rock drill
Preventing wear due to frictional heat rolling the drill bit 2 and chilled
You can do it.

[0007]

Preferably, the liquid is a consolidation liquid such as cement milk. In this case, a soil column 5 extending from the earth and sand layer 3 to the bedrock 4 can be formed. It is also preferable to mix a solution exhibiting elasticity after curing into the consolidation liquid. In this structure, the soil column 5 extending from the earth and sand layer 3 to the bedrock 4 has elasticity and can absorb a horizontal external force such as an earthquake.

In addition, the soil and the consolidation liquid are mixed and a plurality of soil columns 5 whose lower ends reach the inside of the rock 4 are simultaneously formed, or the soil and the consolidation liquid are mixed and the lower ends are mixed. Is formed so that the soil column 5 reaching the inside of the rock 4 is continuous in a partially overlapping state in the lateral direction, or the soil layer 3
It is also preferable to improve the ground over the bedrock 4 and the bedrock 4. By doing so, it is possible to form a column, an underground wall, and a retaining wall in which the soil from the earth and sand layer 3 to the bedrock and the consolidation liquid are mixed and hardened, and to improve the ground.

Further, the apparatus for drilling the earth and sand layer 3 and the bedrock 4 of the present invention provides a hydraulic drilling method for excavating the earth and sand layer from the tip downward.
High-pressure injection function and downhammer 1 for rock excavation
Rock drilling, which has a function of injecting high-pressure gas used for vertically driving the rocker, and which has a diameter larger than the downhammer 1 and drills by rotation above the downhammer 1 which drills the rock 4 by vertical movement. The rotary drill bit 2 is provided. With such a configuration, it is possible to provide a device that can easily perform the drilling from the earth and sand layer 3 to the bedrock 4.

Further, the rotation axis 6 of the lower end down the hammer 1 is provided when both down the hammer 1 the rock cutting rotating drill bit 2 also is larger in diameter than the down hammer 1 to the upper position
It is also preferable to provide a stirring means 7 having a diameter equal to or less than the rock drilling drill bit 2 above the rock drill rotary drill bit 2 on the rotating shaft. With such a configuration, it is possible to provide an apparatus for forming a soil column 5 in which a liquid and a consolidation liquid are stirred and mixed in a borehole from the earth and sand layer 3 to the bedrock 4.

Further, when the fluid is ejected at a high pressure downward from the tip, it is preferable to provide a plurality of ejection holes 8 having different ejection angles. With such a configuration, when excavating the earth and sand layer 3, when loosening the earth and sand layer 3 first with a fluid, the earth and sand below the down hammer 1 and also below the rotary drilling bit 2 for rock cutting. When the layer 3 is loosened, the down hammer 1 and the rotary drilling bit 2 for rock drilling can smoothly excavate the earth and sand layer 3. Moreover, in the rock 4 part, when drilling with the down hammer 1 and the rotary drilling bit 2 for rock drilling, it is possible to blow off the shavings that have been previously rocked, thereby facilitating the excavation of the down hammer 1.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to embodiments shown in the accompanying drawings. Rail 1 of crawler crane 10
An elevating body 12 is suspended so as to be vertically movable along 1. A rotating shaft 6 is rotatably mounted below the elevating body 12, and the rotating shaft 6 is rotated by a motor provided on the elevating body 12. It has become.

A downhammer 1 is attached to the lower end of the rotating shaft 6, and a rotary drilling bit for rock drilling, which has a larger diameter than the downhammer 1 and drills by rotation, is provided above the downhammer 1. 2 is provided. Further, a stirring means 7 such as a stirring blade 7a and a screw portion 7b is provided at a position above the rotary drilling bit 2 for rock drilling of the rotary shaft 6. As the stirring means 7, the screw portion 7b is provided partially or substantially in the vertical direction of the rotating shaft 6 as shown in FIGS. 2, 3 and 15, or is stirred with the screw portion 7b as shown in FIG. Although the wing portion 7a is provided or the illustration is omitted, only the stirring blade 7a is provided, and any of them may be employed.

The rotary shaft 6 is constituted by a pipe having a hollow inside, and a fluid supply pipe is provided in the hollow part inside. The fluid supply pipe is composed of a gas supply pipe 13 and a liquid supply pipe 1.
4. A drilling unit 15 is attached to the lower end of the rotating shaft 6. In the embodiment of FIG. 1, the drilling unit 15 is provided with a down hammer 1 and a rock drilling rotary drilling bit 2.

That is, in the embodiment shown in FIG. 1, the down hammer 1 is provided at the lower part of the cylindrical body 16 forming the outer shell of the excavating unit 15, and the rock drilling excavation is provided at the central part or the upper outer peripheral part of the cylindrical body 16. Bit 2 is provided. The cylindrical body 16 is a cylinder of the down hammer 1, and the upper part of the down hammer 1 is mounted on the lower part of the cylindrical body 16 so as to be vertically movable. The lower part of the vertically movable down hammer 1 is a cylinder 1
6 and projecting downward from the cylindrical body 16.
The drill bit portion 17 has a size substantially equal to the diameter of the rock. In the figure, reference numeral 18 denotes a spring for urging the down hammer 1 upward. A piston 19 for hitting the down hammer 1 is provided inside the cylinder 16 as a cylinder so as to be vertically movable. A gas switching valve 20 is housed in the upper part of the cylindrical body 16 so as to be capable of seesaw movement. Reference numeral 21 denotes an annular gas passage communicating with the gas supply pipe 13 and communicating with the gas switching valve 20. At a position corresponding to one end of the gas switching valve 20, a first gas pressure inlet 22 communicating with the upper inside of the cylinder 16 is bored.
A second gas pressure inlet 23 is perforated at a position corresponding to the other end of the cylinder, and a gas flow passage 25 communicating with the lower chamber of the sliding portion 24 of the piston 19 is perforated in the wall of the cylindrical body 16. The gas flow path 25 and the second gas pressure inlet 23 communicate with each other. Here, 26 in the figure is the leg 2 of the piston 19.
An air exhaust unit 28 that communicates the chamber below 7 with the outside is an exhaust port for exhausting gas in the upper and lower parts of the piston 19. A gas exhaust path 29 whose upper end is an exhaust port 28 is formed in the wall of the cylindrical body 16.
The lower end of 9 is a hole 30 that opens to the inner peripheral surface of the lower end of the cylindrical body 16. On the other hand, a gas discharge passage 31 is provided in the down hammer 1, and an upper portion of the gas discharge passage 31 is a hole 32 opened on a side surface of the down hammer 1, and the hole 30 and the hole 32 described above are formed. Communicating. Here, at least one of the hole 30 and the hole 32 is a long hole that is long in the vertical direction, and the communication relationship between the hole 30 and the hole 32 is maintained even when the down hammer 1 moves up and down. It is set so that. The lower portion of the gas discharge passage 31 provided in the down hammer 1 is branched into a plurality of portions, and serves as gas injection holes 8a.

A liquid supply path 33 is provided in the wall of the cylindrical body 16 and connected to the liquid supply pipe 14 in a state where the excavating unit 15 is connected to the lower end of the rotary shaft 6. The lower end portion is a hole portion 34 that opens to the inner peripheral surface of the lower end portion of the cylindrical body 16. On the other hand, a liquid passage 36 is provided in the down hammer 1, and an upper portion of the liquid passage 36 is a hole 35 opened on a side surface of the down hammer 1, and the hole 34 and the hole 35 are formed as shown in FIG. Are communicated as shown in FIG. Here, at least one of the hole 34 and the hole 35 is a long hole that is long in the vertical direction, and the communication relationship between the hole 34 and the hole 35 is maintained even when the down hammer 1 moves up and down. It is set so that. The lower portion of the liquid passage 36 provided in the down hammer 1 is branched into a plurality of portions, and forms a liquid injection hole 8b.

Here, the liquid is ejected downward from the plurality of liquid ejecting holes 8b. When the liquid is ejected downward, the angle of the ejection direction with respect to the vertical line, that is, the ejection angle, Are different from each other. here,
One of which is downward injection close to vertical and the other is downward injection obliquely downward, or both are downward injection obliquely downward, but the angle between both is perpendicular to the vertical line is changed It is. In any case, by injecting the liquid at a high pressure downward, it is set so that the lower ground can be relaxed by the liquid to be injected at a high pressure below the down hammer 1 and before the down hammer 1 in this case. Since the angles formed by the vertical lines of the plurality of injection directions are different from each other as described above, not only the ground below the down hammer 1 but also the rock drilling drill bit 2 having a larger diameter than the down hammer 1. It is designed to be injected ahead of the ground.

Also, the direction of the gas injected from the plurality of gas injection holes 8a is set to an angle formed with respect to the vertical line, that is, the injection angle is set to a different angle. here,
The operation of raising and lowering the down hammer 1 will be described below with reference to FIGS. 5 to 8. First, a gas such as pressurized air is supplied from the gas supply pipe 13 to the annular gas passage 21. At this time, the gas switching valve 20 is inclined so that the right side of the gas switching valve 20 is at the bottom, and the first gas pressure inlet 22 is closed, and flows in from the second gas pressure inlet 23 via the gas flow path 25. The gas pushes the piston 19 upward. Further, when the piston 19 reaches just before the top dead center, the pressure above the piston 19 becomes equal to or higher than the supply pressure, and the gas switching valve 20 reverses so that the left side of the gas switching valve 20 becomes lower. Therefore, the first gas pressure inlet 22 shown in FIG.
The gas is press-fitted into the upper part of the piston 19 as shown by the arrow a, and the piston 19 descends while the gas below the piston 19 is exhausted from the air exhaust part 26 as shown by the arrow b in FIG. As described above, the piston 19 descends and the down hammer 1 is hit by the leg 27 of the piston 19 to cut the rock.

When the piston 19 is lowered, gas above the piston 19 is exhausted from the exhaust port 28 as shown by an arrow c in FIG. 6, while gas below the sliding portion 24 of the piston 19 is discharged as shown in FIG. As shown by an arrow d, the gas is supplied to the second gas pressure
And the second gas pressure inlet 23 is opened. As a result, as shown by an arrow e in FIG. 7, gas is injected from the second gas pressure inlet 23 through the gas flow path 25 below the sliding portion 24 of the piston 19, and the reaction force striking the down hammer 1 and the above The piston 19 is pushed up by the gas, and when the piston 19 comes to the upper part as shown in FIG. 8F, the pressure above the piston 19 rises as described above and the gas switching valve 20 is inverted.

In this manner, the piston 19 strikes the down hammer 1 while repeatedly moving up and down in the order of FIG. 5, FIG. 6, FIG. 7, and FIG. It enables rock drilling of rocks. As described above, the rotary drilling bit 2 for rock drilling is provided at a position above the down hammer 1, but the rotary drilling bit 2 for rock drilling has a diameter larger than the diameter of the rock bit 17 below the down hammer 1. It has become. A lower portion of the rock drilling excavation bit 2 is provided with a blade portion 35 formed of a strong blade material capable of drilling a rock mass by rotating, as well as excavating the earth and sand layer 3 by rotation. The blade portion 35 is arranged such that the outer side is located higher. That is, since the inner blade portion 35a is located at the lower side and the outer blade portion 35b is located at the upper side, in excavation, first, a small-diameter excavation is performed at the inner blade portion 35a, and then the outer blade portion 35a is excavated. Excavation with a large diameter can be performed at the portion 35b.

To attach the upper end of the cylindrical body 16 of the excavating unit 15 to the lower end of the rotary shaft 6, a fitting projection 36 having a polygonal cross section is provided at the lower end of the rotary shaft 6. Is provided with a fitting concave portion 37 having a polygonal cross section.
6 is fitted into the fitting recess 37, the pin 60 is inserted from the pin hole 38, and the pin 60 is locked in the locking recess 39.

The diameter of the stirring means 7 provided on the rotating shaft 6 is equal to or smaller than the diameter of the rock drilling drilling bit 2, that is, the diameter of the stirring means 7 is equal to or smaller than the diameter of the rock drilling rotary drilling bit 2. Has become. Next, a method of continuously drilling from the earth and sand layer 3 to the bedrock 4 using the apparatus having the above configuration will be described.

First, when excavating the earth and sand layer 3, the rotating shaft 6
To move the apparatus downward while injecting a consolidation liquid such as cement milk from the plurality of liquid injection holes 8b provided in the rock bit 17 below the downhammer 1 at a high pressure. Here, when excavating the earth and sand layer 3, the down hammer 1 does not operate. This is down hammer 1
When the is moved up and down, the earth and sand layer 3 below the down hammer 1 is in a state of being squeezed, which hinders excavation, and the down hammer 1 does not operate. Thus, while rotating the rotating shaft 6, a consolidation liquid such as cement milk is injected at a high pressure downward from the plurality of liquid injection holes 8 b provided in the drill bit 17 below the down hammer 1. Since the earth and sand layer 3 below the down hammer 1 is excavated while being loosened prior to the down hammer 1, the down hammer 1 can smoothly go down. Here, the down hammer 1 is smaller than the hole diameter to be formed (that is, the hole diameter to be formed is the diameter of the rock drilling drill bit 2). It is possible to move down smoothly into the layer 3. In the upper position of the down hammer 1, the rock drilling drill bit 2 having a diameter larger than that of the down hammer 1 is rotated, thereby loosening and excavating the excavated soil layer 3 by the high-pressure injection of the consolidation liquid. As a result, the earth and sand layer 3 can be excavated to a large diameter at a high excavation speed even though the down hammer 1 is provided. During this time,
The consolidation liquid and the excavated earth and sand are stirred and mixed by the stirring means 7.

When the down hammer 1 at the tip reaches the bedrock 4 by excavating the earth and sand layer 3 in this manner, high-pressure gas is supplied to the gas supply pipe 13 while the rotation of the rotating shaft 6 is continued, and Activate the hammer 1. By supplying the high-pressure gas and operating the down hammer 1 to move it up and down as described above, the small diameter hole is drilled while hitting the rock 4 with the rock bit 17 below the down hammer 1. . In this way, the rock 4 is drilled to a small diameter by the down hammer 1 and cracks and the like are generated in the rock around the drilled small hole, and then the rock drilling located on the upper part of the down hammer 1 is performed. The rock 4 is drilled to a large diameter by the rotary drilling bit 2 for use. Here, as described above, a small-diameter hole is formed in the rock 4 by the small-diameter down hammer 1 and cracks are generated around the small-diameter hole, so that a large-diameter rock drilling rock is formed by rotation. Even the rotary drill bit 2 can easily drill a rock to form a target large-diameter hole. Moreover, in this case, since the blade portion 35 of the rock drilling drilling bit 2 is arranged to be positioned higher as it goes to the outside, the periphery of the small-diameter drill hole previously drilled by the down hammer 1 is formed. First, rock is drilled by the rotation of the inner blade portion 35a located below, and then the outer peripheral portion is rocked by the outer blade portion 35b. It can be formed on the bedrock 4. During the rock cutting as described above, the high-pressure gas used to operate the down hammer 1 is injected from the plurality of gas injection holes 8a, and blows off the shavings shaved by the down hammer 1 to form the down hammer 1 and the rock. This facilitates drilling by the rotary drilling bit 2.

A solidifying solution may be injected into the rock drilling of the bedrock 4. In this case, the consolidation solution is simultaneously injected with the gas at a high pressure during the rock drilling of the bedrock 4. When the consolidating liquid is injected, the rock bit 4 17 and the rotary drilling bit 2 for rock drilling below the downhammer 1 are cooled while the rock 4 is rocked, and the downhammer 1 and the rotary drilling bit 2 for rock drilling are cooled. It will be possible to prevent wear due to frictional heat by cooling.

After drilling the rock 4 to a predetermined depth as described above, the rotating shaft 1 is pulled up. At the time of raising the rotating shaft 6, it is preferable to pull up while stirring and mixing the consolidation liquid and the excavated earth and sand while rotating the rotating shaft 6 forward or backward, but it is also possible to stop the rotation and pull up. At the time of lifting, the consolidation liquid may or may not be jetted. Also,
Either gas may or may not be injected at the time of lifting, but when the gas is injected, the stirring effect is improved.

In this way, a soil hardened body (that is, a soil column 5) obtained by stirring and mixing the consolidation liquid and excavated earth and sand is formed so as to extend from the earth and sand layer 3 to a predetermined depth of the bedrock 4. By continuing the soil columns 5 formed as described above, a retaining wall or an underground wall whose lower portion reaches the inside of the bedrock 4 can be formed. Further, it is possible to continuously the soil column 5, or distance lower by Oite multiple form to a ground improvement leading to the rock 4.

The rotating shaft 6 may be a single shaft, or may be a multi-axis as shown in FIG. Here, in the case of multi-axis,
As shown in FIG. 3, the adjacent excavating units 15 are vertically displaced. In FIG. 3, the rotation trajectories of the rock drilling rotary excavation bits 2 of the adjacent excavation units 15 partially overlap in plan view. Therefore, when this apparatus is used, a plurality of The soil columns 40 in which the soil columns 5 partially overlap can be formed by a single excavation.
Then, a continuous wall can be formed by further overlapping the end portions of the thus formed soil column array 40. Alternatively, the rotation trajectories of the rock drilling rotary excavation bits 2 of the adjacent excavation units 15 may be in contact in plan view. When this apparatus is used, the soil column 40 in contact with the soil column 5 can be formed by one excavation as shown in FIG. Then, by continuously forming the soil column 40 thus formed, a continuous wall can be formed. The above-mentioned wall may be formed not only as an underground wall and a retaining wall, but also as a ground improvement as described above.

In the above-described embodiment, an example in which a consolidating liquid such as cement milk is used as the liquid to be jetted, but a solution exhibiting elasticity after curing is mixed into this consolidating liquid. You may. As the solution exhibiting elasticity after curing, a synthetic resin liquid such as a polyurethane resin exhibiting elasticity after curing is used. Of course not limited to this exemplary product, any solution properties having elasticity after curing
If, it may be others. When a solution exhibiting elasticity after curing is mixed into the consolidation liquid in this way, the formed soil column 5 (or a continuous one) has elasticity by itself, and the This can absorb the external force of the above, prevent the occurrence of cracks, prevent the strength from decreasing, and prevent the water stoppage from decreasing.

In the embodiment shown in FIG. 1, a fitting projection 36 at the lower end of the rotary shaft 6 is provided, and a fitting recess 37 at the top of the cylindrical body 16 is fitted and engaged with a pin. The drilling unit 15 is removed by removing the pin,
FIG. 1 shows a bit 50 dedicated to a general earth and sand layer 3 which is conventionally known.
6, it can be used as a general drilling device.

FIGS. 17 to 19 show another embodiment of the present invention. In the present embodiment, the upper end of the second excavation unit 15b having the large-diameter rotary drilling bit 2 for rock drilling of the present invention is detachably attached to the lower end of the rotating shaft 6, and furthermore, the second excavation unit The upper end of the first excavating unit 15a equipped with the down hammer 1 may be detachably attached to the lower end of 15b.
Here, the same structure as the above-described structure for mounting the rotating shaft 6 and the excavating unit 15 can be employed for mounting each component. In this embodiment, the same mechanism as that of the above-described embodiment can be adopted as the mechanism of the down hammer 1.

[0033]

According to the first aspect of the present invention, as described above, a down hammer which has a function of injecting a fluid at a high pressure downward from a tip and drills a rock by vertical movement is provided. When excavating up to the sediment layer and the bedrock below the sediment layer using a device provided with a rotary drilling bit for rock drilling having a diameter larger than that of the down hammer and drilling by rotation at the top, a high pressure gas is applied to the tip of the down hammer.
Gas injection hole for high pressure injection of liquid and high pressure injection of liquid
In the excavation of the earth and sand layer, a liquid is ejected from the tip of the down hammer with high pressure to excavate the hole below the down hammer, and the earth drilling is performed by rotating the rock drilling excavation bit above the down hammer. Drill the layer and reach the bedrock from the tip of the down hammer
The high-pressure gas used to drive the down hammer up and down is ejected with high pressure, and the down hammer is moved up and down to rock the rock to a small diameter, and the portion cut by the down hammer to the small diameter is rotated. The drilling bit for rock drilling drills a large diameter, so despite the provision of a down hammer at the lower end, when excavating the sediment layer, the high pressure liquid precedes the sediment layer below the small diameter down hammer. The down hammer can be moved down smoothly by loosening and excavating, and the down hammer can be made to go down more smoothly because the down hammer has a small diameter, and it rotates at the upper position of the down hammer The drilling bit for rock drilling makes it possible to easily and reliably drill a large-diameter earth and sand layer. As a result, a down hammer is provided. Despite this, the excavation of the sediment layer can be performed smoothly and accurately in a short time, and when excavating the rock, first, a small diameter hole is drilled while drilling the rock into a small diameter with a down hammer. The surrounding area of the small diameter drilled hole can be subsequently drilled to the target diameter by the large diameter drilling bit for rock drilling, and the large diameter drilling is also possible. In addition, high-pressure gas is injected at high pressure into the drilling of the rock to blow off the powder generated by rock drilling and facilitate drilling of the rock with a down hammer or rotary drilling bit for rock drilling. Things. In addition, drilling of earth and sand layer
When drilling, a liquid is ejected as a fluid,
And the excavated earth and sand are stirred and mixed.
High was used to vertically drive the Dow Nhanma as
Since the pressurized gas is injected, the liquid and the earth and sand layer were mixed and stirred.
The soil column can be formed, and when drilling rock
The high-pressure gas used to drive the
In addition, it can be used effectively and injected.

[0034]

According to the second aspect of the present invention, in addition to the effects of the first aspect of the present invention, since the liquid is a consolidation liquid such as cement milk, the soil hardened material is used as a soil cement. A cured product can be formed. Further, in the invention according to claim 3 , in addition to the effect of the invention according to claim 2 , a soil formed by mixing a solution exhibiting elasticity after curing into a consolidation liquid is formed. The cured body has elasticity, and an external force such as an earthquake can be absorbed by the soil cured body itself.

According to a fourth aspect of the present invention, in addition to the effects of any one of the first to third aspects, in addition to mixing the earth and sand with the consolidation liquid, Since a plurality of soil columns reaching the inside of the bedrock are formed at the same time, a row of soil columns extending from the lower part to the inside of the bedrock can be simultaneously formed. Further, in the invention according to claim 5 , in addition to the effects of the invention according to any one of claims 1 to 3 , the earth and sand and the consolidation liquid are mixed and the lower end is formed in the rock. By forming the soil columns that reach up to the soil part so that they partially overlap in the horizontal direction, it is possible to easily form a row of soil columns in which the lower part of the soil pillars that extend into the bedrock partially overlap in the horizontal direction. is there.

Further, in the invention described in claim 6, in addition to the effect of the invention according to any one of claims 1 to 5, since the ground improvement over the soil layer and the rock, the lower The ground improvement up to the inside of the bedrock can be easily performed. In the invention according to claim 7 , the liquid is injected at high pressure when excavating the earth and sand layer from the tip downward.
Function to drive down hammer up and down during rock excavation
A rotary drilling bit for drilling rock, which has a function of injecting the high pressure gas used for the high pressure at high pressure and drills rock by vertical movement, is provided above a down hammer which drills rock by drilling. Therefore, it is possible to provide a device capable of drilling from the earth and sand layer to the inside of the bedrock with a simple configuration.

Further, in the invention according to claim 8, in addition to the effect of the invention of the seventh aspect, from down hammer in the upper position of both down hammer The provision of down hammer at the lower end portion of the rotary shaft A rock drilling drilling bit with a large diameter is provided, and a stirring means with a diameter smaller than the rock drilling drilling bit is provided above the rotary drilling drilling bit on the rotating shaft. When drilling, the excavated earth and sand and the liquid can be stirred and mixed at the same time during excavation.

According to the ninth aspect of the present invention, in addition to the effects of the seventh or eighth aspect of the present invention, when the fluid is jetted at a high pressure downward from the tip, the injection holes having different jetting angles are provided. Since a plurality of cavities are provided, when excavating the sediment layer, when loosening the sediment layer ahead of the fluid, it is possible to loosen the sediment layer not only below the down hammer but also below the rock drilling rotary drill bit, The down hammer and the rock drilling drill bit can smoothly excavate the sediment layer, and in the rock part, the rock drilled prior to drilling with the down hammer and the rock drill rotary drill bit is used. The powder can be blown away to facilitate the excavation of the down hammer.

[Brief description of the drawings]

FIG. 1 is an exploded sectional view of an embodiment of the present invention.

FIG. 2 is a front view of the same.

FIG. 3 is an overall front view of the same, partially broken away.

FIG. 4 is a schematic bottom view showing a positional relationship between an inner blade portion and an outer blade portion of the rock drilling rotary excavation bit.

FIG. 5 is an explanatory diagram showing an operation order of the down hammer of the above.

FIG. 6 is an explanatory diagram showing an operation order of the down hammer of the above.

FIG. 7 is an explanatory diagram showing an operation order of the down hammer of the above.

FIG. 8 is an explanatory diagram showing an operation order of the down hammer of the above.

FIG. 9 is an explanatory view showing a communicating portion between a hole at an end of the liquid supply path and a hole at an end of the liquid passage.

FIG. 10 is an explanatory view showing a state where the earth and sand layer is excavated.

FIG. 11 is an explanatory view showing a state where the rock is excavated.

FIG. 12 is a horizontal cross-sectional view of an example of a soil cured product formed by the method of the present invention.

FIG. 13 is a horizontal cross-sectional view of another example of the same soil cured product.

FIG. 14 is a front view of another embodiment of the device of the present invention.

FIG. 15 is a front view of still another embodiment of the device of the present invention.

FIG. 16 is a front view showing an example in which the excavating unit of the present invention is detached from the rotary shaft and a conventionally known bit dedicated to a general earth and sand layer is attached.

FIG. 17 is a front view of still another embodiment of the device of the present invention.

FIG. 18 is a front view of still another embodiment of the device of the present invention.

FIG. 19 is a front view of still another embodiment of the device of the present invention.

[Explanation of symbols]

 Reference Signs List 1 down hammer 2 rotary drilling bit for rock drilling 3 earth and sand layer 4 bedrock 5 soil column 6 rotating shaft 7 stirring means 8 injection hole

Claims (9)

(57) [Claims] 1. A rock drill having a function of injecting a fluid at a high pressure downward from a tip and drilling a rock by rotating above a down hammer which drills a rock by vertical movement. When excavating to the sediment layer and the bedrock below the sediment layer using a device equipped with a rotary drill bit , high-pressure gas is applied to the tip of the down hammer.
Gas injection hole for pressure injection and high pressure injection of liquid
When excavating the sediment layer, a liquid is ejected from the tip of the down hammer at a high pressure to excavate the lower part of the down hammer and drill the lower part of the down hammer. excavating, the Dow from the tip of the down hammer reaches the bedrock
Rock excavation for rock drilling, in which a down hammer is moved up and down while high- pressure gas used to drive the hammer up and down is moved up and down to rock the rock to a small diameter, and the part cut by the down hammer is turned into a small diameter. A method for drilling a soil layer and a bedrock, which comprises drilling a large diameter with a bit. 2. A method of liquid is boring the soil layer and the rock as claimed in claim 1, characterized in that the consolidating fluid such as cement milk. 3. The method for drilling a soil layer and a rock according to claim 2, wherein a solution exhibiting elasticity after hardening is mixed into the consolidation liquid. 4. according to any one of claims 1 to 3 and the lower end by mixing the excavated soil and consolidating fluid is characterized by reclamation plurality of soil columns extending up the bedrock simultaneously A method of drilling a soil layer and a bedrock. 5. The method according to claim 1, wherein the excavation and consolidation liquid are mixed, and a soil column having a lower end extending into the rock is formed so as to be continuous in a partially overlapped state in the lateral direction.
A method for drilling the earth and sand layer and the bedrock according to claim 3 . 6. A method of drilling a soil layer and the rock according to any one of claims 1 to 5, characterized in that ground improvement over the soil layer and the rock. 7. When excavating a sediment layer from the tip downward.
High pressure liquid injection and down hammer during rock excavation
A rotary excavator for rock drilling, which has a function of injecting high pressure gas used to vertically drive a rock and has a diameter larger than the down hammer and drills by rotation above a down hammer which drills rock by vertical movement. An apparatus for drilling a soil layer and a bedrock, comprising a bit. 8. provided rock cutting rotary drilling bits larger diameter than the down hammer position above the rotary shaft lower end portion to both the down hammer The provision of down hammer, the upper rock cutting rotary drill bit of the rotary shaft 8. The apparatus for drilling a soil layer and a bedrock according to claim 7, wherein a stirring means having a diameter equal to or smaller than a rotary drilling bit for rock drilling is provided at the position. 9. A fluid from the tip downwards Upon high pressure injection, cutting the soil layer and the rock of claim 7 or claim 8, wherein the comprising a plurality of different injection holes of the injection angle A device to punch.