JPS60203728A - Ground improving device - Google Patents

Abstract

PURPOSE:To enable formation of a large cavity through a single nozzle, by a method wherein a nozzle, through which high pressure excavating water is injected, is installed to the forward end part of an excavation pipe in a manner that it is made movable horizontally and constantly in a discharge direction through a parallel movement mechanism. CONSTITUTION:A nozzle 17b is installed to the forward end of an excavation pipe 15 of a ground improving device through a parallel movement mechanism 41 formed with plural links 41a, 41b, 41c, and 41d. After the nozzle is inserted through an excavated hole down to a specified depth, with the excavation pipe 15 rotated forwardly and reversely, high-pressure excavation water 29 is injected against a wall surface 32a through the nozzle 17b to form a cavity 32. With the backward movement of a wall surface 32a along with excavation, a hydraulic jack 41e is contracted. The nozzle 17b is protruded in a condition that it is maintained in a horizontal direction, and after excavation is completed, a ground improving agent is fed through the excavation pipe 15 to build an artificial ground.

Description

Detailed Description of the Invention (a) 1 Technical Field of the Invention The present invention involves forming a cylindrical cavity in the ground by injecting high-pressure water horizontally after drilling a pilot hole in the ground. The present invention relates to a ground modification device suitable for application to a ground modification method, etc. in which a new ground is formed by pouring a soil improvement agent such as concrete into the formed cavity.

(b), Background of the technology When constructing an artificial ground ζζ, an underground Zζ cavity is excavated and that part is replaced with a ground improvement agent such as concrete 1.
As a result, a method of constructing a solid plate-shaped artificial ground underground has been proposed (Japanese Patent Laid-Open No. 57-133918, Japanese Patent Laid-open No. 57-133918,
8-24020, JP-A-58-26115, FFIji
(Sho 58-20819, etc.)

In method B, the ground is excavated by injecting ultra-high pressure water from a nozzle.
As the distance from the nozzle to the wall of the cavity to be co-cut increases as excavation progresses, the excavation ability of ultra-high pressure water decreases.

(C), Prior art and problems Therefore, in order to solve these problems, please wait for JFJ M
58-240201 and Oi-1: In addition to the normal nozzle, another nozzle is installed at the tip of the rotatable stirring blade, and if the diameter of the cavity is small, excavation is performed with the normal nozzle, and the diameter of the cavity is In cases where it became difficult to demonstrate sufficient excavation capacity with the existing nozzle due to the expansion of the agitator, a method was proposed in which the stirring blade was rotated open and the nozzle at its tip was used to excavate. ing. This method requires two types of nozzles, one for short-distance excavation and one for long-distance S excavation, which has the disadvantage of complicating the structure of the soil modification device. Since it is stored along the axis of the tube and is spread out like an umbrella when in use, the height of the cavity must be sufficient for the rotation of the stirring blades, and if the cavity is too flat, However, there was an inconvenience that the stirring blade could not be rotated from the stored position, making it impossible to excavate.

Another option is to simply increase the jetting pressure of drilling water using a normal nozzle, but the pressure of drilling water is still several hundred atmospheres, and in order to increase it even further, it is necessary to use a pump or high-pressure This method has the disadvantage that ancillary equipment such as liquid supply pipes becomes larger and more precise.

Furthermore, FIG. 6 shows another conventional proposal example. This method uses a single nozzle 17
This is a case where it is provided so that it can be freely rotated in the horizontal direction with respect to 5.
Although this method requires only one nozzle 17,
Since the discharge direction of 7 is not determined and draws a circular arc, the cavity 32 excavated by this also has a bottom that draws a circular arc, and the cavity 32
This had the disadvantage of creating process waste, such as the need for corrective excavation after excavation.

(d) 0 Purpose of the Invention In order to eliminate the above-mentioned drawbacks, the present invention is capable of excavating a large-diameter cavity with a single nozzle, regardless of the flat shape of the cavity, and requires only a small amount of incidental equipment such as a pump. The first object of the present invention is to provide a ground modification device that can maintain a constant nozzle discharge direction, and the second purpose is to provide a ground modification device that can maintain a constant nozzle discharge direction.

(e) 0 Structure of the Invention That is, the present invention is constructed by installing a nozzle in an excavation pipe so that it can be freely projected and moved in the horizontal direction through parallel motion 4A JR, and the discharge direction of the nozzle is always constant. Ru.

(Margin below) (f) 0 Examples of the invention Examples of the present invention will be described below based on the drawings. will be explained in detail.

Fig. 1 is a front view showing one 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 an enlarged front view of the nozzle shown in Fig. 2 extended. FIG. 4 is an enlarged front view showing another embodiment of the present invention, and FIG. 5 is an enlarged front view when the nozzle of FIG. 4 is extended.

As shown in FIG. 1, the ground modification device 1 includes a mobile heavy machine 2 such as a crawler crane, and a mobile type 4A2 is provided with a driver's seat 2a, crawlers 2b, 2b, etc. Further, a pillar-shaped leader 3 is erected on the mobile heavy equipment 2 via a support frame 5, and a guide rail 3a is attached to the leader 3.
are formed 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 movable 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 freely moves in the vertical direction, that is, in the direction of the arrow CXD, along the guide rail 3a of the leader 3. I can do it with O.

The excavation pipe holding/rotating device 6 is provided with a chuck 9 rotatable in the direction of arrow A1B by a rotary drive means 10 such as a motor built in the principle pipe holding/rotating device 6. A hollow cylindrical rod 13 constituting the tube 15 is inserted through the tube 13 so as to be freely graspable and fixed, and flanges 13a and 13'a 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. 1 via flanges 13a by fastening means such as bolts.
This flange connection allows the excavation pipe 15 to
Even when the rods 5 are rotated forward and backward in the direction of arrow A1B, the connections between the rods 13 do not become loose as would occur when connecting with screws. The lower end of the excavation pipe 15 forms an opening 15a open to the outside, and a drilling bit 16 is attached to the lower end. Also, Pi')・16
Slightly above the ultrasonic range sensor 19 and parallel movement mechanism 4
1 is provided.

As shown in FIG. 2, the parallel motion mechanism 41 has a plurality of links 41 a, 4 l b, 4 c, and 41 d, and the rotation center of the links 41 a and 41 b and the rotation center of the links 41 c and 41 d are A hydraulic jack 41e is provided in between, with the tips of rams 41f, 41f protruding from both the upper and lower sides pivotally mounted.

A nozzle 17 is pivotally attached to the left end of the links 41b and 41d with its discharge port 17b facing horizontally, and a flexible high-pressure liquid supply pipe 20 is attached to the nozzle 17.
is connected. The high-pressure liquid supply pipe 20 is extended in the axial direction of the excavation pipe 15, that is, upward in FIG. There, it is connected to a flexible tube 22 having flexibility.

On the other hand, at the upper end of the excavation pipe 15, a
A flexible tube 25 is connected.

Since the ground modification device 1 has the above configuration, in order to construct an artificial ground using the ground modification device 1, first move the excavation pipe holding and rotation device 6 along the guide rail 3a of the leader 3 in the direction of arrow C. The chuck 9 is pulled up, and the rotation driving 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 drilling pipe 15 gripped by the chuck 9 also rotates in the direction A, and the bit 16 at the tip of the drilling pipe 15 is moved downward in FIG. Start drilling towards the target. As the excavation pipe holding rotation device 6 moves in the D direction on the leader 3, and the excavation pipe 15 and therefore the bit 16 move downward, the bit 1 is disposed in the soil in the C and D directions.
A pilot hole 26 as a locus of 6 is drilled and formed.

The pilot hole 26 is supplied with muddy water 27 to prevent the pilot hole 26 from collapsing due to its hydrostatic pressure, and the muddy water 27 in the pilot hole 26 is pumped through the flexible tube 25 by a suction pump (not shown) to remove the excavated earth and sand generated by the bit 16. In principle, the slurry is sucked up and discharged from the pipe opening 1.5a through each rod 13 inside the excavation pipe 15 to the outside of the pilot hole 26. The discharged muddy water 27 is returned to the pilot hole 26 after separating the suctioned earth and sand, and is continuously used for excavation.

A chuck 9 that rotationally drives the excavation pipe 15 is used as a prototype.
The rotary driving means 10 continues to excavate by repeating forward and reverse rotations 17 within an angular range of 360 degrees, but since the excavation pipe 15 does not rotate more than 360 degrees, a flange is attached to the top of the excavation pipe 15. The muddy water 27 is smoothly discharged from the flexible tube 25 which is fixedly connected via the flexible tube 13a without causing excessive twisting to the flexible tube 25.

In addition, during the I principle of the pilot hole 26, the parallel motion mechanism 4
1, the hydraulic jack 41e has its ram 41.1 as shown in FIG. f and 41f are both in an extended state, so the parallel movement mechanism 41 moves the nozzle 17 into the excavation pipe J.
It is in a state where it is folded to the 5th side.

In this state (the distance L1 from the tip of the nozzle 17 to the axis of the drilling pipe 15 is the pylon), the radius of the hole 26 is smaller than the radius of the hole 26, so the principle of drilling the pilot hole 26 with the bit 16 and the drilling pipe 15 is This is carried out smoothly without the nozzle 17 coming into contact with the wall surface of the pilot hole 26 being excavated.

In this way, when the pilot hole 26 is cut to a certain depth and the drilling pipe holding and rotating device 6 reaches below the leader 3, the driving of the rotational drive means 10 is stopped to stop the drilling operation, and the chuck 9 1. Stop holding the bent pipe 15, remove the flexible tube 25 at the upper end of the excavated pipe 15, and connect a new rod 3.

Therefore, only the excavation pipe holding and rotating device 6 is pulled up in the C direction along the leader 3, and the newly connected tx rod 1 is
Grip the excavation pipe 15 through three parts.

Next, the flexible tube 25 is fixedly connected to the upper end of the newly connected rod 13, and in this state, the rotary drive means 10 of the tube holding and rotating device 6 is driven again to start cutting the pilot hole 26 once. . In this way, the pilot hole 26 is gradually formed in the D direction, and the depth becomes DP.
When the excavation by the bit 16 is reached, the excavation by the bit 16 is stopped, and the excavation pipe body holding rotary device W6 is pulled up by Ll together with the excavation pipe 15. Therefore, this time, ultra-high pressure water 29 is ejected from the nozzle 17 from the flexible tube 22 via the high-pressure liquid supply pipe 20.

At this time, when the excavation pipe holding rotation device 6 is lowered in the direction D by an excessive amount of t, and the excavation pipe 15 is rotated reciprocatingly in the forward and reverse directions over 360 degrees as described above, there are A cylindrical cavity 32 is formed by the high pressure water 29.

Ultra-high pressure water spouting from nozzle 17 29 18! The cutting ability decreases as the distance from the discharge port 17b of the nozzle 17 increases in the horizontal direction. Ram 4If
, 41f at a constant speed in the direction of arrow E in FIG.

Then, the links 41 n, 41 of the parallel motion mechanism 41
b, 41c, and 41d, the nozzle 17 is moved in the C direction, while its discharge port 17b remains in the horizontal direction.
That is, the third
As shown in the figure, the nozzle 17 protrudes and moves until the distance between the tip of the nozzle 17 and the axis of the excavation pipe 15 reaches L2. Then, nozzle 1
7 and the cavity wall surface 32a, which is the surface to be excavated, is significantly shortened compared to the previous storage state of the nozzle 17,
The excavation ability of the ultra-high pressure water 29 from the nozzle 17 is significantly improved, and a cavity 32 having a large diameter can be smoothly and reliably excavated and formed.

Note that since the high-pressure liquid supply pipe 20 is formed to have flexibility, even if the nozzle 17 moves in the horizontal directions G and H, the connection between the high-pressure liquid supply pipe 20 and the nozzle 17 remains good. will be maintained. Furthermore, when cutting the cavity 32, the excavation pipe 15 rotates only within an angle range of 3600 degrees, so the connection state between the high-pressure liquid supply pipe 20 installed in the excavation pipe 15 and the flexible tube 22 is such that the duplex 22 is fa! It is well maintained without getting entangled with the cut pipe 15, and the supply of ultra-high pressure water 29 is performed smoothly.
Therefore, the formation of the cavity 32 is also performed 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. It is possible to accurately grasp the situation by checking the details.

In this way, by appropriately retracting the parallel movement mechanism 41 by 1 in a manner that matches the diameter of the cavity 32 being excavated, the nozzle 17 is moved in the G1 direction and the excavation ability of the nozzle 17 is maintained at a high level. I'm going to work on it (.

Once a cavity 32 of a predetermined size has been formed in the ground 31, one nozzle 17 is pulled up from the bottom of the cavity 32 in the direction C while rotating the excavation pipe 15, and cement milk is poured from the flexible tube 22 into the nozzle 17. , etc., and inject the ground improving agent into the cavity 32 from the nozzle 17 at high pressure to fill the cavity 32 with the soil improving agent (the excavated pipe 15 is used as a Remy pipe, and the opening 15a is filled with the soil improving agent). A ground improvement agent such as concrete 1 may be filled into the cavity 32 and the pilot hole 26 through the hole 26. ). At this time as well, by spouting the improving agent while moving the nozzle 17 appropriately in the G and H directions, the improving agent can be efficiently and reliably filled into the cavity 32.

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

-By the way, artificial ground was constructed in some places, and the transfer RFDJ
Move the heavy weight 4312 and newly make four holes 26 in the position adjacent to the constructed artificial ground,
A cavity 32 is constructed, and a soil improvement agent is then filled, and the cavity 32 is horizontally connected to the previously constructed cavity 32 (the soil improvement agent has already been filled and solidified) to form an artificial ground. will be expanded.

Note that the parallel movement machine $41 for the nozzle 17 can be used as long as the nozzle 1'7 can be moved horizontally while the discharge direction of excavation water such as ultra-high pressure water from the nozzle 17 always maintains a constant direction. Any structure of mechanism may be used, for example, as shown in FIGS. 4 and 5,
A horizontal rank mechanism is used as the parallel movement mechanism 41, and a hydraulic jack 41e drives the link 41d to move the nozzle 17 fixed to the tip of the link 41c from the distance 11LI to L.
Of course, it is also possible to make it protrude up to 2.

Furthermore, the guide means such as the leader 3 for supporting and guiding the layered pipe holding and rotating device 6 does not necessarily need to be attached to the mobile heavy equipment 2 etc., but if the guide means is provided on the mobile type vIt2, Efficiently drilling a large number of pilot holes 26 results in 5J performance.

(g) 6 Effects of the Invention As explained above, according to the present invention, the nozzle 17 can be moved horizontally to the excavation pipe 15 via the parallel movement mechanism 41, and the discharge direction of the nozzle 17 is always fixed. Since the distance X is set to be constant, the distance X between the nozzle 17 and the wall surface 32a during excavation can be kept short by moving the nozzle 17 in the horizontal direction as appropriate depending on the diameter of the cavity 32 during excavation. Large diameter cavity 3
2, 1a easily without increasing the discharge pressure of excavation water such as ultra-high pressure water from the nozzle 17! It is possible to remove
The incidental equipment φlit such as a pump can be small, and the overall configuration of the ground modification device 1 can be simplified and miniaturized. Furthermore, compared to the conventional method of excavating a large-diameter cavity by rotating a nozzle installed separately from a normal nozzle using a stirring blade, the nozzle can be freely moved horizontally regardless of the flatness of the cavity. Not only can the nozzle be made to protrude, but also a large-diameter cavity can be effectively excavated with a single nozzle, making it possible to demonstrate powerful excavation ability with a simple configuration.

Furthermore, since the discharge direction of the nozzle 17 is always maintained constant in the horizontal direction, the nozzle 1 shown in FIG.
7, the bottom of the cavity 32 is not excavated in a circular manner, and a highly reliable ground modification device 1 can be provided.

Note that since the parallel motion mechanism 41 stirs the excavated soil in the muddy water 27, the muddy water 27 from the excavated pipe 15
and S can easily suck up and discharge earth and sand,

[Brief explanation of drawings]

Fig. 1 is a front view showing one 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 an enlarged front view of the nozzle shown in Fig. 2 extended. 4 is an enlarged front view showing another embodiment of the present invention, FIG. 5 is an enlarged front view of the nozzle shown in FIG. 4 when extended, and FIG. 6 is a conventional nozzle. FIG. 2 is a front view showing a proposed example. 1...Ground modification device 15...Drilling pipe 16...Bit 17...Nozzle 29...Drilling water (ultra high pressure water) 31. ...Ground 41...Parallel motion mechanism Applicant Mitsui Construction Co., Ltd. NIT Co., Ltd. Agent FP Physician Tomi 1) Shinji Diagram 6 Procedural Amendment (Method) 1 Indication of the case Showa 1959 Patent Application No. 19020 2 Name of the invention Ground modification device 3 Relationship with the case of the person making the amendment Patent applicant address 3-10-1 Iwamoto-cho, Chiyoda-ku, Tokyo Name (Name) Mitsui Construction Co., Ltd. Representative Machida Ryoji Address: 1752 Zushicho, Machida City, Tokyo Name:
Nissan Freeze Co., Ltd. Representative Motohiro Goto 6 Full text of the specification to be amended 7 Engraving of the specification of the amendment (no changes to the content)

Claims (1)

[Claims] It has a rotatable drilling pipe with a bit attached to its tip, a nozzle is provided at the tip of the drilling pipe, and high-pressure laI cutting water is spouted from the nozzle to drill the ground around the pilot hole. In the ground remodeling equipment for excavating, the nozzle is installed in the excavation pipe so that it can be freely projected and moved in the horizontal direction via a parallel FDJ machine 4 (FF), and the discharge direction of the nozzle is always constant. ground modification equipment.