JPH0579766B2 - - Google Patents

Description

[Detailed description of the invention] (a) Industrial application field The present invention involves drilling a pilot hole underground and then spraying high-pressure water horizontally to form a cylindrical cavity underground. The present invention relates to a ground remodeling device suitable for application to a ground remodeling method in which a new ground is formed by pouring a ground improvement agent such as concrete into a formed cavity.

(b) Conventional technology When constructing an artificial ground, a cavity is excavated underground and the hollow part is replaced with a ground improvement agent such as concrete, resulting in the construction of a plate-shaped solid artificial ground underground. A construction method has been proposed to
133918, JP 58-24020, JP 58-26115, JP 58-20819, etc.).

(c) Problems to be solved by the invention In this construction method, the surrounding ground is excavated using ultra-high pressure water and the excavated soil is discharged to the outside through an excavation pipe. If the size of the earth and sand is larger than the opening through which the excavation pipe inhales the earth and sand, there is a risk that the excavation pipe will be blocked by the earth and sand.

SUMMARY OF THE INVENTION In view of the above-mentioned circumstances, it is an object of the present invention to provide a ground modification device with a low risk of blockage of an excavation pipe.

(d) Means for solving the problem That is, the present invention provides an earth and sand crushing device 43 on the upper part of the bit 16, and a crushing cutter 4 of the earth and sand crushing device 43.
6 facing the excavation pipe opening 15a.

Note that the numbers in parentheses are for convenience and indicate corresponding elements in the drawings, and therefore, this description is not limited to the descriptions in the drawings. The same applies to the column "(e). Effect" below.

(e) Operation With the above-described configuration, the present invention operates so that the earth and sand crushing device 43 crushes excavated earth and sand.

(f) Embodiments Hereinafter, embodiments of the present invention will be described based on the drawings.

FIG. 1 is a front view showing an embodiment of the ground modification device according to the present invention, FIG. 2 is an enlarged front view of the vicinity of the nozzle of the ground modification device shown in FIG. 1, and FIG. 3 is a side view of FIG. 2. .

As shown in FIG. 1, the ground modification device 1 includes a mobile heavy machine 2 such as a crawler crane, and the mobile heavy machine 2 is provided with a driver's seat 2a, crawlers 2b, 2b, and the like. Further, a columnar leader 3 is erected on the mobile heavy equipment 2 via a support frame 5, and a guide rail 3a is formed on the leader 3 in the vertical direction in the figure. A drilling pipe holding and rotating device 6 is provided on the guide rail 3a so as to be able to move up and down, and one end of a wire 7, the other end of which is wound around a winch (not shown), is connected to the drilling pipe holding and rotating device 6. has been done. Therefore, by driving the winch in the forward and reverse directions to pay out or retract the wire 7, the excavation pipe holding and rotating device 6 moves in the up and down direction along the guide rail 3a of the leader 3, that is, in the direction of arrows C and D.
You can move freely in any direction.

The excavation pipe holding and rotation device 6 is provided with a chuck 9 rotatable in the directions of arrows A and B by a rotary drive means 10 such as a motor built in the excavation pipe holding and rotation device 6. drilling pipe 15
A hollow cylindrical rod 13 constituting the rod 13 is installed through the rod 13 so as to be able to be gripped and fixed, and flanges 13a, 13a for connection are formed at both upper and lower ends of the rod 13. A plurality of rods 13 are connected in series at the lower part of the rod 13 in FIG.
Even if the rod rotates forward or backward in the directions of arrows A and B, each rod 13
There is no possibility that the connection between the two will become loose as would occur with a screw connection. As shown in FIG. 2, the lower part of the excavation pipe 15 has an offset portion 15b formed in a shape slightly offset laterally with respect to the rotation center CL of the excavation pipe 15.
An opening 15a is provided at the tip of the offset portion 15b.
It is formed in a shape that faces diagonally downward in the figure. A plate 15c is provided on the excavation pipe 15, facing downward in FIG. 2, and at the lower end of the plate 15c,
A drilling bit 16 is attached. Also, slightly above bit 16, as shown in FIG.
An ultrasonic ranging sensor 19 and a cylinder device 41 are provided. The cylinder device 41 is a cylinder 41
b, and the cylinder 41b has a rod 4
1a is supported so as to be movable in the directions of arrows E and F, which are the directions of injection of excavation water. A passage 41c is formed in the rod 41a along the axis of the rod 41a, and the tip of the passage 41c, that is, the rod 41a
A nozzle 41d is provided at the tip. Furthermore, a high pressure liquid supply pipe 20 and a control pressure oil pipe 42 are connected to both sides of the cylinder 41b in FIG. 3 via ports 41e and 41f. It is installed extending along the outer periphery of the excavation pipe 15 in the axial direction of the pipe 15, that is, upward in FIG. It is connected to the tube 22, etc. (In order to make the diagram easier to read, only the high pressure liquid supply pipe 20 is shown in FIG. 1, but the same applies to the control pressure oil pipe 42). On the other hand, a flexible tube 25 that is similarly flexible is connected to the upper end of the excavation tube 15.

Further, above the bit 16, an earth and sand crushing device 43 is provided at the offset portion 15b of the excavation pipe 15, as shown in FIGS. 2 and 3, and the earth and sand crushing device 43 is attached to the plate 15c. It has a hydraulic motor 45. An output shaft 45a of the hydraulic motor 45 protrudes downward in FIG.
, the crushing cutter 46 is inserted into the opening 15 of the excavation pipe 15.
a and are provided to face each other through a hole 15d formed in the plate 15c.

Since the ground modification device 1 has the above configuration, in order to construct an artificial ground using the soil modification device 1, first move the excavation pipe holding and rotating device 6 along the guide rail 3a of the leader 3 in the direction of arrow C. In the lifted state, the rotation drive means 10 in the excavation pipe holding and rotation device 6 is driven to rotate the chuck 9, for example, in the A direction. When the chuck 9 rotates, the excavation pipe 15 held by the chuck 9 also rotates in the direction A.
The bit 16 at the tip of the excavation pipe 15 starts to excavate downward in FIG. 1 due to the weight of the excavation pipe holding and rotating device 6 and the excavation pipe 15. The excavation pipe holding rotation device 6 moves in the D direction along the leader 3, and the excavation pipe 15,
Therefore, as the bit 16 moves downward, a pilot hole 26 is excavated in the soil in the C and D directions as the locus of the bit 16. Pilot hole 2
6 is supplied with muddy water 27, its hydrostatic pressure prevents the pilot hole 26 from collapsing, and a suction pump (not shown) pumps the flexible tube 2.
5, the muddy water 27 in the pilot hole 26 is sucked up and discharged to the outside of the pilot hole 26 through each rod 13 inside the excavation pipe 15 from the excavation pipe opening 15a in a slurry form together with the excavated earth and sand generated by the bit 16. . The discharged muddy water 27 is separated from the suctioned earth and sand, and then flows into the pilot hole 26.
and used for continuous drilling. Note that during excavation, the hydraulic motor 45 is driven to rotate the crushing cutter 46. Then, the excavated soil sucked in from the opening 15a of the excavation pipe 15 passes through this crushing cutter 46 portion and is sucked into the excavation pipe 15, so that the excavated soil is absorbed into the excavated soil more than the opening 15a of the excavation pipe 15. Even if there is a large lump, the earth and sand is crushed by the crushing cutter 46 and sucked up into the excavation pipe 15 without clogging the excavation pipe 15.

In addition, during excavation, the chuck 9 that rotationally drives the excavation pipe 15 continues excavation while repeating forward and reverse rotation within a 360° angle range by the rotation drive means 10, but the excavation pipe 15 rotates more than 360°. Therefore, the muddy water 27 can be smoothly discharged from the flexible tube 25 fixedly connected to the upper part of the excavation pipe 15 via the flange 13a without giving extreme twist to the flexible tube 25.

Note that while the pilot hole 26 is being drilled, pressure oil is supplied to the port 41f of the cylinder device 41 via the control pressure oil pipe 42, and the rod 41a is connected to the piston 4.
1g in the direction of arrow F, the rod 41a and therefore the nozzle 41d are in a retracted state. In this state, the distance L1 from the tip of the nozzle 41d to the axis of the drilling pipe 15 is
Since the radius L3 is smaller than the radius L3, the pilot hole 26 is smoothly excavated by the bit 16 and the drilling pipe 15 without the nozzle 41d coming into contact with the wall surface of the pilot hole 26 being excavated.

Further, as shown in FIG. 2, the maximum offset amount L4 of the offset portion 15b of the excavation pipe 15 is
Since the diameter is smaller than the radius L3 of the hole to be drilled by the bit 16, the rotation of the drilling pipe 15 in the directions of arrows A and B is performed smoothly without the offset portion 15b and the pilot hole 26 interfering with each other.

In this way, the pilot hole 26 is excavated to a certain depth, and when the excavation pipe holding rotary device 6 reaches below the leader 3, the driving of the rotary drive means 10 is stopped to stop the excavation operation, and the excavation by the chuck 9 is stopped. The grip on the pipe 15 is stopped, the flexible tube 25 at the upper end of the excavation pipe 15 is removed, and the rod 13 is newly connected. Therefore, only the excavation pipe holding and rotating device 6 was pulled up in the C direction along the leader 3, and
The excavation pipe 15 is gripped via the newly connected rod 13 portion. Next, the flexible tube 25 is fixedly connected to the upper end of the newly connected rod 13, and in this state, the excavation tube holding and rotating device 6 is connected again.
The pilot hole 26 is rotated by driving the rotary drive means 10 of
Start excavation. In this way, the pilot hole 26
is gradually formed in the D direction, and when the depth reaches DP, the excavation by the bit 16 is stopped and the excavation pipe holding rotation device 6 is moved together with the excavation pipe 15.
Raise only L1. Therefore, this time, ultra-high pressure water 29 is supplied from the flexible tube 22 to the port 41 of the cylinder device 41 via the high-pressure liquid supply pipe 20.
supply to e. Then, the supplied ultra-high pressure water 2
9 is ejected from the nozzle 41d in the direction of arrow E in FIG. 3 through a flow path 41c formed within the rod 41a. At this time, while gradually lowering the excavation pipe holding rotation device 6 in the direction D, the excavation pipe 15 is
When rotated back and forth over 360° in the forward and reverse directions,
A cylindrical cavity 32 is excavated into the ground 31 using ultra-high pressure water 29. At this time, pressure oil is also supplied from the port 41f side of the cylinder 41b, and the force with which the pressure oil presses the piston 41g in the direction of arrow F is greater than the force with which the ultra-high pressure water 29 pushes the piston 41g in the direction of arrow E. Since the pressure is greater than the pressing force, the ultra-high pressure water 29 is injected from the nozzle 41d while the rod 41a remains in the retracted state.
Further, even during excavation using the ultra-high pressure water 29, the excavated soil is discharged to the outside via the excavation pipe 15, but the excavated soil generated as a result of excavation using the ultra-high pressure water 29 is also removed by the crushing cutters of the earth crushing device 43. 46 finely pulverizes the excavated soil immediately before the opening 15a, so that the excavated soil can be smoothly sucked up by the excavated soil without clogging the excavated pipe 15.

On the other hand, the ultra-high pressure water 29 spouted from the nozzle 41d
The excavation capacity of the cylinder decreases as the distance increases from the nozzle 41d in the horizontal direction (in the directions of arrows E and F). The supply of pressure oil to the device 41 is stopped. Then, the force that had been pushing the piston 41g in the direction of the arrow F is lost, so the piston 41g, together with the rod 41a, moves in the direction of the arrow E under the pressure of the ultra-high pressure water 29.
The nozzle 41d projects in the horizontal direction, that is, in the direction of the wall surface 32a of the cavity 32 being excavated. In this way, only the distance L2 shown in FIG.
When the nozzle 41d moves in the direction of arrow E, which is the injection direction of the ultra-high pressure water 29, the distance between the nozzle 41d and the cavity wall surface 32a is shortened by a distance L2 compared to the previously stored state of the nozzle 17, and the nozzle 41
The excavation ability by the ultra-high pressure water 29 from d is improved, and the cavity 32 having a large diameter can be smoothly and reliably excavated and formed. In addition, nozzle 4
In order to move 1d backward in the direction of arrow F, pressure oil is supplied to port 41f via control pressure oil pipe 42. Then, the piston 41g is moved by the rod 41 due to the pressure oil.
The nozzle 4 is pressed and moved in the direction of arrow F along with a.
1d also retreats in the F direction.

In addition, when cutting the cavity 32, the excavation pipe 15 is
Since it only rotates within a 360° angle range, the drilling pipe 1
The state of connection between the high-pressure liquid supply pipe 20 and the flexible tube 22 installed at 5 is maintained well without the tube 22 getting entangled with the excavation pipe 15, and the supply of ultra-high pressure water 29 is performed smoothly. The formation of the cavity 32 is also carried out without any hindrance. The shape of the cavity 32 during excavation is determined by transmitting ultrasonic waves 33 from the ultrasonic distance measurement sensor 19 to the cavity wall surface 32a, capturing the reflected waves, and measuring the distance from the ultrasonic distance measurement sensor 19 to the wall surface 32a. By doing so, you can understand accurately.

In this way, the cylinder device 41 is driven appropriately,
By projecting and retracting the nozzle 41d in the directions of arrows E and F, work can be carried out while maintaining a high level of excavation ability of the nozzle 41d.

Once a cavity 32 of a predetermined size has been formed in the ground 31, while rotating the excavation pipe 15 and pulling up the nozzle 41d from the bottom of the cavity 32 in the C direction, cement milk, etc. is poured from the flexible tube 22 into the nozzle 41d. The soil improving agent is injected from the nozzle 41d into the cavity 32 at high pressure to fill the cavity 32 with the soil improving agent. Cavity 32 and pilot hole 26
A ground improvement agent such as concrete may be filled inside. ). At this time as well, by spouting the improving agent while moving the nozzle 41d in the E and F directions as appropriate,
The improving agent can be efficiently and reliably filled into the cavity 32.

In this way, when the excavation pipe 15 is pulled up in the direction C while filling the ground improvement agent into the cavity 32 and the pilot hole 26, the filled improvement agent solidifies and a strong artificial ground is constructed in the ground 31. That will happen.

Once one artificial ground has been constructed, the mobile heavy equipment 2 is moved, a new pilot hole 26 is excavated in a position adjacent to the constructed artificial ground, a cavity 32 is constructed, and a ground improvement agent is added. The artificial ground is expanded by filling the cavity 32 with the previously constructed cavity 32 (in which the ground improvement agent has already been filled and solidified) and making it horizontally continuous.

Note that the guide means such as the leader 3 that supports and guides the excavation pipe holding/rotating device 6 is not necessarily the guide means for supporting and guiding the excavation pipe holding/rotating device 6.
Although it is not necessary that the guide means be attached to the movable heavy equipment 2, it becomes possible to efficiently excavate a large number of pilot holes 26 if the mobile heavy equipment 2 is provided with a guide means.

(g) Effect of the Invention As explained above, according to the present invention, the earth and sand crushing device 43 is provided on the upper part of the bit 16, and the crushing cutter 46 of the earth and sand crushing device 43 is provided in a form facing the excavation pipe opening 15a. Since the excavated earth and sand produced as a result of excavation are finely crushed by the crushing cutter 46 before being sucked into the excavation pipe 15,
The risk of being blocked by large excavated earth and sand can be greatly reduced.

[Brief explanation of the drawing]

FIG. 1 is a front view showing an embodiment of the ground modification device according to the present invention, FIG. 2 is an enlarged front view of the vicinity of the nozzle of the soil modification device shown in FIG. 1, and FIG. 3 is a side view of FIG. 2. . 1... Ground modification device, 15... Excavation pipe, 15a
...Opening, 16...Bit, 29...Drilling water (ultra high pressure water), 31...Ground, 41d...Nozzle, 4
3... Sediment crushing device, 46... Crushing cutter.

Claims (1)

[Scope of Claims] 1. A rotatable drilling pipe with a bit attached to the tip thereof is provided, and a nozzle is provided at the tip of the drilling pipe, and high-pressure drilling water is spouted from the nozzle to drain the ground around the pilot hole. A ground modification device for excavating soil, comprising: an earth and sand crushing device provided above the bit; and a crushing cutter of the earth and sand crushing device facing the opening of the excavation pipe.