JP2019112892A - Ground improvement apparatus and ground improvement method - Google Patents

Abstract

To provide a ground improvement apparatus and a ground improvement method that can perform a ground improvement by means of machine agitation without making a construction machine installed on the ground large in size.SOLUTION: The ground improvement apparatus includes a rod unit 2, an agitation unit 3 that is supported by the rod unit 2 rotatably and that has an ejection port 33 ejecting a solidification material being supplied into the ground, an agitation power unit 4 that is attached to the rod unit 2 and that drives the agitation unit 3 rotationally by means of supplied power, and a reaction force unit 5 that is attached to the rod unit 2 and that ensures reaction force against the rotation of the agitation unit 3. The agitation unit 3 includes a shaft part 31 supported by the rod unit 2 rotatably and a plurality of agitation blades 32 extending radially from the shaft part 31. The reaction force unit 5 includes a cylindrical defining frame 51 covering the agitation unit 3 and a plate-like reaction force blade 53 attached outside the cylindrical defining frame 51.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a ground improvement device and a ground improvement method for improving ultra soft ground.

  Conventionally, as ground improvement technology of mixing soil with soft ground with solidified material such as cement to construct improved soil, those by mechanical agitation and those by jet grout have been adopted (for example, Patent Documents 1 and 2) reference).

  Ground improvement by mechanical agitation inserts a rod into the ground, and creates an improved ground by rotating a stirring blade attached to the tip of the rod while ejecting a solidifying material. In addition, jet grout ground improvement creates an improved ground by inserting a rod into the ground and injecting high pressure from the tip of the rod in the horizontal direction.

Japanese Patent Laid-Open No. 7-82736 JP, 2013-147805, A

  However, in the prior art, it is necessary to insert a rod into the ground and install a large heavy machine such as an earth auger on the ground to rotate the rod. Therefore, when the ground improvement of the ultra-soft ground constructed by pumping under pressure soil is to be improved, large heavy equipment can not be placed directly on the ultra-soft ground, and temporary ground improvement is provided on the surface before being placed on the ultra-soft ground. It is necessary to improve the bearing capacity by If a large heavy machine is placed on an extremely soft ground, the bearing capacity is not obtained, and the heavy machine is inclined and falls, or problems such as being unable to move due to settlement occur, and the construction is stopped.

  In addition, mechanical stirring has a merit that a finished product of the improved body is clear and a homogeneous improved body is obtained as compared with the jet grout, and the waste associated with the construction is relatively small. However, heavy machines for mechanical stirring are large in size and heavy as compared to heavy machines for jet grout because the weight of the rod and the stirring blade is large and torque for rotating the rod is required. Therefore, in the ground improvement by mechanical agitation, it is necessary to make the surface improvement thickness of the surface to be ground improved, as compared with the jet grout.

  The present invention has been made in consideration of the above-described circumstances, and provides a ground improvement device and a ground improvement method capable of performing ground improvement by mechanical agitation without increasing the size of a construction machine installed on the ground. The purpose is

In order to achieve the above object, according to the present invention, there is provided a rod portion, a stirring portion rotatably supported by the rod portion, and a stirring portion having a jet port for spouting the supplied solidified material into the ground; A stirring power unit that rotationally drives the stirring unit by the supplied power, and a reaction force unit that is attached to the rod unit and that secures a reaction force against the rotation of the stirring unit.
Furthermore, in the present invention, the reaction force portion may include a cylindrical demarcated frame covering the stirring portion, and a plate-like reaction force wing attached to the outside of the demarcated frame. The ground improvement device according to claim 1 characterized by things.
Furthermore, in the present invention, the stirring portion is a shaft portion rotatably supported by the rod portion;
A plurality of stirring blades extending radially from the shaft portion may be provided, and the jet nozzle may be formed in the stirring blades.
Furthermore, in the present invention, a plurality of the jet outlets different in distance from the central axis of the rod portion may be formed.
Furthermore, in the present invention, the jet nozzle may be formed on the rear side in the rotational direction of the stirring blade.
Furthermore, in the present invention, the stirring power unit includes a plurality of power sources for rotationally driving the stirring unit, and the plurality of power sources have a mass distribution around the axis of the rod portion so as to be rotationally symmetric. You may be attached to the said rod part.
Furthermore, in the present invention, a helical wing that generates a propulsive force that moves downward or upward by rotation, and a propulsion power unit that is attached to the rod portion and that rotationally drives the helical wing by the supplied power are provided. It is good.
A ground improvement method for improving a target ground using the above ground improvement device, comprising: a lifting machine for suspending the ground improvement device by a hanging rope attached to one end of the rod portion; and solidifying the stirring portion A solidifying material supply unit for supplying the material and a power supply unit for supplying power to the stirring power unit on the target ground, and the lifting rope is fed by the lifting machine to make the ground improvement device the target ground While being solidified, the solidifying material is supplied from the solidifying material supply device to the stirring unit, and power is supplied from the power supply device to the stirring power unit, and the solidifying material is jetted from the jet port. The stirring unit may be driven to rotate, and the improved body may be formed by mixing the solidified material and the soil.
Furthermore, in the present invention, the improved body may be formed while the ground improvement device sunk to the target ground is pulled up by the lifting machine.
Furthermore, in the present invention, during the settlement of the ground improvement device, power is supplied from the power supply device to the stirring power unit without supplying the solidifying material from the solidifying material supply device to the stirring unit. The stirring unit may be rotationally driven.

  According to the present invention, since it is not necessary to transmit the rotational driving force from the construction machine installed on the ground to the stirring unit 3, the ground improvement by mechanical agitation is performed without increasing the size of the construction machine installed on the ground. The effect of being able to

FIG. 1 is a top view and a side view showing a configuration of a first embodiment of a ground improvement device according to the present invention. It is a perspective view which shows the structure of the stirring part shown in FIG. It is a figure which shows the supply mechanism of the solidification material to the stirring blade shown in FIG. It is AA sectional drawing and BB sectional drawing which are shown in FIG. It is explanatory drawing explaining the ground improvement method using the ground improvement apparatus shown in FIG. It is explanatory drawing explaining the ground improvement method using the ground improvement apparatus shown in FIG. It is a side view showing composition of a 2nd embodiment of a ground improvement device concerning the present invention. It is CC sectional drawing and DD sectional drawing which are shown in FIG.

  Hereinafter, an embodiment of a ground improvement device concerning the present invention is described with reference to an accompanying drawing. In the following embodiments, the same reference numerals are given to the configurations showing the same functions.

First Embodiment
The ground improvement device 1 according to the first embodiment is a device for ground improvement of a very soft ground such as that obtained by pumping a buried soil and constructing it by mechanical agitation without using rotational torque from heavy equipment installed on the ground. is there.

  Referring to FIG. 1, the ground improvement device 1 includes a rod portion 2 having a predetermined length, a stirring portion 3 rotatably supported by the rod portion 2, a stirring power portion 4 for rotationally driving the stirring portion 3, and a stirring portion A reaction force unit 5 for securing a reaction force to the rotation of 3 is provided. In FIG. 1, (a) is a top view, and (b) is a side view in which a part of the reaction force portion 5 is omitted.

  The rod portion 2 is formed on an upper portion of the base 21, which rotatably supports the stirring portion and supports the stirring power portion 4 and the reaction force portion 5 in a state in which movement of at least the circumferential direction is restricted or fixed. , And a mounting portion 22 to which a hanging rope body 6 such as a wire or a rod is mounted. The hanging cord 6 and the base 21 may be directly fixed by welding or the like. In the present embodiment, the base 21 has a cylindrical or cylindrical shape, and rotatably supports the stirring unit 3 on the circumferential surface. In addition, the cross-sectional shape of the base 21 is not limited to a circular shape at the attachment portion of the stirring power unit 4 and the reaction force unit 5, and may be polygonal as long as the mass distribution around the axis is rotationally symmetric.

  The stirring unit 3 includes a shaft portion 31 rotatably supported by the rod portion 2 and a plurality of stirring blades 32 radially extending from the shaft portion 31 at equal intervals. Stirring portion 3 mixes the solidifying material supplied from above the ground by solidifying material supply hose 7 by rotation, and soil to form an improved body. The solidifying material is grout (slurry) of cement milk, mortar, synthetic resin or the like. The solidifying material supply hose 7 is introduced from the upper portion of the base 21 of the rod portion 2 into the inner space of the base 21 as shown in FIG. 1B, and supplies the solidifying material to the stirring blade 32. And the stirring blade 32 functions also as a solidification material injection part which makes a ground material eject a solidification material.

  The shaft portion 31 is a cylindrical body, and the base 21 of the rod portion 2 is penetrated on the inner periphery. The shaft 31 is rotatably supported by the base 21 by a bearing mechanism (not shown).

  The number and shape of the stirring blades 32 are not limited as long as the solidifying material and the soil can be mixed as the stirring unit 3 is rotationally driven. In the present embodiment, as shown in FIG. 2, the stirring blade 32 is formed of a cylindrical rod-like body. A plurality of stirring blades 32 extending radially (in the normal direction) at equal intervals from the shaft portion 31 are respectively provided in three steps of the lower, middle and upper stages. The length in the normal direction of the agitating blade 32 is set so as to be the shortest at the lower end and gradually increase toward the upper end.

  The stirring unit 3 is rotationally driven by the stirring power unit 4 in the direction indicated by the arrow X in FIG. In the stirring blade 32, a jet port 33 for jetting a solidifying material into the ground is formed on the rear side in the rotational direction. Thereby, since the solidified material can be jetted out into the soil stirred by the stirring blade 32, the mixing of the solidified material and the soil is promoted. Furthermore, the rotational driving force of the stirring unit 3 can be complemented by the ejection of the solidifying material. Further, the distance from the central axis of the rod portion 2 to the jet 33 is set such that the lower end is the shortest, and the distance toward the upper end gradually increases. Thereby, the solidifying material can be ejected uniformly into the ground. The jets 33 do not have to be formed on all the stirring blades 32, and may be formed on only some of the stirring blades 32.

  Referring to FIG. 3, a flow path 34 of the solidifying material communicating with the jet port 33 is formed in the stirring blade 32. In the rod portion 2, the solidified material supply hose 7 for supplying the solidified material from above the ground is disposed in the hollow part of the base 21, and the discharge port 23 communicated with the solidified material supply hose 7 in the substrate 21. Is formed. A communication groove 35 communicating the flow passage 34 and the discharge port 23 is formed on the inner circumferential surface of the shaft portion 31 along the entire circumference. Thereby, the solidifying material supplied from above the ground by the solidifying material supply hose 7 is jetted from the jet port 33 through the discharge port 23, the communication groove 35 and the flow path 34.

  The stirring power unit 4 includes a power source 41 and a power source fixing portion 42 for fixing the power source 41 to the base 21 of the rod portion 2 when referring to the A-A sectional view of FIG. 4. A plurality of power sources 41 are fixed to the base 21 by a power source fixing portion 42 such that the mass distribution around the axis of the rod portion 2 is rotationally symmetric. As the power source 41, a hydraulic motor or an electric motor can be used. The power of the power source 41 is supplied from the super soft ground, and when a hydraulic motor is employed as the power source 41, hydraulic energy is supplied from the super soft ground through the hydraulic hose 8. When the hydraulic hose 8 is connected to the power source 41 through the inside of the base 21 of the rod portion 2, as shown in FIG. 1 (b), the hydraulic hose 8 is a rod in the same manner as the solidifying material supply hose 7. It is preferable because it can be introduced from the top of the base 21 of the part 2 into the inner space of the base 21 to simplify the hose processing.

  The shaft portion 31 of the stirring unit 3 on the stirring power unit 4 side is provided with a hollow portion 37 in which an internal gear 36 is formed on the inner peripheral surface, as shown by the B-B cross section in FIG. A spur gear 44 engaged with the internal gear 36 is attached to an end of the power source 41 which extends to the hollow portion 37 of the rotation shaft 43. Thereby, the rotational driving force is transmitted to the shaft portion 31 of the stirring unit 3 by the power source 41, and the stirring unit 3 is rotationally driven.

  The reaction force portion 5 covers the stirring portion 3 and is attached to the outer periphery of the frame 51, a frame fixing portion 52 for fixing the frame 51 to the base 21 and a cylindrical frame 51 for defining the finished shape of the improvement body. And the reaction blade 53 for securing a reaction force when the stirring blade 32 rotates to mix the soil and the solidifying material.

  The frame 51 is fixed by the frame fixing portion 52 so that the axis is coaxial with the base 21. The inner circumference of the definition frame 51 is larger than the rotation trajectory of the stirring blade 32, and the upper and lower lengths of the definition frame 51 are set to a length that covers at least the stirring portion 3. Thereby, the range in which the solidifying material and the soil are mixed by the stirring portion 3 is limited to the inner periphery of the defining frame 51, and the finished shape of the improved body is defined.

  The reaction force wing 53 is a plate-like body attached to the outer periphery of the defining frame 51, and is disposed so that the plate surface is substantially perpendicular to the rotation direction of the stirring unit 3. A plurality of (four in the present embodiment) the reactive blade 53 is provided such that the mass distribution around the axis of the rod portion 2 is rotationally symmetric. And the reaction force wing | blade 53 is set to the area from which sufficient reaction force is obtained so that the whole ground improvement apparatus 1 may not rotate, when the stirring part 3 rotates.

Next, the ground improvement method using the ground improvement apparatus 1 of this embodiment is demonstrated in detail with reference to FIG.5 and FIG.6.
First, as shown in FIG. 5A, a lifting machine 9 for suspending the ground improvement device 1, a solid material supply device 10 for supplying a solid material to the stirring portion 3 of the ground improvement device 1, and the ground improvement device 1. A power supply device 11 for supplying power to the stirring power unit 4 is installed as a construction machine on the super soft ground. In FIGS. 5 and 6, the solidifying material supply hose 7 and the hydraulic hose 8 are not shown.

  The lifting machine 9, the solidified material supply device 10, and the power supply device 11 can be distributed and arranged. In addition, since the lifting machine 9 does not require a power for rotating the ground improvement device 1, a normal crane having only a lifting function can be used. Therefore, since the construction machine installed on the super soft ground becomes lightweight, the construction machine can be installed only by laying a plate having a large flat area on the ultra soft ground, and the surface layer improvement becomes unnecessary. In addition, it is possible to carry out construction by loading construction machines on the ship if it is possible to obtain the water depth of the ship in the middle of the reclamation by the dredged soil.

  Next, the hanging rope body 6 is sent out by the lifting machine 9, and as shown in FIG. 5 (b), the ground improvement device 1 is made to sink to the seabed ground which is a support layer in the ultrasoft ground by its own weight. The settlement of the ground improvement device 1 is performed by supplying hydraulic energy from the power supply device 11 to the stirring power unit 4 without supplying the solidifying material from the solidifying material supply device 10 to the stirring unit 3. It is preferable to rotate and drive the super soft soil while stirring. In this case, since the resistance of the soil is reduced by the stirring, the ground improvement device 1 can be sunk smoothly. Moreover, when the hanging rope body 6 is used as a rod, the ground improvement apparatus 1 can also be stuffed into super soft ground by the lifting machine 9.

  Next, the hanging rope body 6 is received by the lifting machine 9, and as shown in FIG. 6A, while the ground improvement device 1 is pulled up, the solidifying material is supplied from the solidifying material supply device 10 to the stirring unit 3 Hydraulic energy is supplied from the supply device 11 to the stirring power unit 4. Thereby, the stirring unit 3 is rotationally driven while ejecting the solidifying material, and the improved body 12 is formed by mixing the solidifying material and the soil. Since the improvement body 12 is formed as the ground improvement device 1 is pulled up, it is formed to extend upward from the seabed ground.

  Further, the improvement body 12 is formed in a state of being defined by the definition frame 51 of the reaction force portion 5. Accordingly, the compounding amount of the solidifying material can be accurately set by the pulling speed of the ground improvement device 1 and the supply amount of the solidifying material, and an improved body having a desired strength can be formed.

  FIG. 6 (b) shows a state in which the ground improvement device 1 is pulled up to the supersoft ground and the improved body 12 is completed. As described above, the super soft ground is improved by installing the lifting machine 9, the solidifying material supply device 10 and the power supply device 11 instead of the large auger such as the earth auger on the ultra soft ground. Body 12 can be built.

  The improved body 12 can also be formed during the settlement of the ground improvement device 1. However, when the ground improvement device 1 is pulled up, since the formed improved body 12 becomes a resistance, it becomes difficult to pull up the ground improvement device 1 on the same track as that at the time of settlement, and enlargement of the lifting machine 9 is necessary. Become. Therefore, as described above, it is preferable to form the improvement body 12 only at the time of pulling up without forming the improvement body 12 during the settlement.

Second Embodiment
With reference to FIG. 7, in addition to the configuration of the ground improvement device 1 of the first embodiment, the ground improvement device 1a of the second embodiment has a lower side propulsion supported rotatably at the lower end portion of the base 21 in the rod portion 2. The lower propulsion power unit 14 rotationally driving the section 13, the lower propulsion unit 13, the upper propulsion unit 15 rotatably supported at the upper end of the base 21 of the rod unit 2, and the upper propulsion unit 15 And an upper propulsion power unit 16 for driving the motor.

  The lower propulsion unit 13 includes a cylindrical lower shaft portion 131 annularly mounted on the base 21 of the rod portion 2, and a spiral wing 132 attached to the outer periphery of the lower shaft portion 131. The lower side shaft portion 131 is rotatably supported by a bearing mechanism such as a bearing provided between the base 21 and the lower side shaft portion 131. In addition, the movement of the lower shaft portion 131 in the axial direction is restricted so as not to come off the base 21.

  When the lower propulsion unit 13 is rotationally driven, the spiral wing 132 generates a propulsive force that the ground improvement device 1a advances downward or upward according to the rotation direction.

  The lower propulsion power unit 14 includes a power source 141 and a power source fixing portion 142 for fixing the power source 141 to the base 21 of the rod portion 2 when referring to the cross-sectional view of FIG. A plurality of power sources 141 are fixed to the base 21 by a power source fixing portion 142 so that the mass distribution around the axis of the rod portion 2 is rotationally symmetric. As the power source 141, a hydraulic motor or an electric motor can be used. The power of the power source 141 is supplied from the super soft ground, and when a hydraulic motor is used as the power source 141, hydraulic energy is supplied from the super soft ground through a hydraulic hose (not shown).

  The lower shaft portion 131 of the lower propulsion unit 13 extends to the lower propulsion power unit 14, and a spur gear 133 is formed at its end as shown in FIG. A spur gear 144 engaged with the spur gear 133 is attached to the rotation shaft 143 of the power source 141. Thus, the rotational drive force of the power source 141 is transmitted to the lower shaft portion 131 of the lower propulsion unit 13, and the lower propulsion unit 13 is rotationally driven.

  The upper propulsion unit 15 includes a cylindrical upper shaft 151 annularly mounted on the base 21 of the rod 2 and a spiral wing 152 attached to the outer periphery of the upper shaft 151. The upper shaft portion 151 is rotatably supported by a bearing mechanism such as a bearing provided between the base 21 and the upper shaft portion 151. Further, the movement of the upper shaft portion 151 in the axial direction is restricted so as not to come off the base 21.

  When the upper propulsion unit 15 is rotationally driven, the spiral wing 152 generates a propulsion force that causes the ground improvement device 1a to move downward or upward according to the rotation direction.

  The upper propulsion power unit 16 is composed of a power source 161 and a power source fixing portion 162 for fixing the power source 161 to the base 21 of the rod portion 2 with reference to the D-D sectional view of FIG. A plurality of power sources 161 are fixed to the base 21 by a power source fixing portion 162 so that the mass distribution around the axis of the rod portion 2 becomes rotationally symmetric. As the power source 161, a hydraulic motor or an electric motor can be used. The power of the power source 161 is supplied from the super soft ground, and when a hydraulic motor is used as the power source 161, hydraulic energy is supplied from the super soft ground through a hydraulic hose (not shown).

  The upper shaft portion 151 of the upper propulsion unit 15 extends to the upper propulsion power unit 16, and a spur gear 153 is formed at an end portion thereof as shown in FIG. A spur gear 164 meshing with the spur gear 153 is attached to the rotation shaft 163 of the power source 161. Thereby, the rotational drive force of the power source 161 is transmitted to the upper shaft portion 151 of the upper propulsion unit 15, and the upper propulsion unit 15 is rotationally driven.

  As a result, when the ground improvement device 1a is sunk, the downward propelling portion 13 and the upper propelling portion 15 are rotated to generate a propelling force that travels downward, and when pulling up, the reverse of the lower propelling portion 13 and the upper propelling portion 15 The rotation can generate an upward thrust. Accordingly, the ground improvement device 1a can be sunk smoothly, and a smaller lifting machine 9 can be employed.

  Although the lower propulsion unit 13 and the upper propulsion unit 15 are provided in the ground improvement device 1a, either the lower propulsion unit 13 or the upper propulsion unit 15 may be provided. Further, the power source 161 may be fixed to the base 21 of the rod portion 2 by using the power source fixing portion 42 of the stirring power portion 4 which rotationally drives the stirring portion 3.

As described above, in the present embodiment, the rod portion 2, the stirring portion 3 having the ejection port 33 which is rotatably supported by the rod portion 2 and ejects the supplied solidified material into the ground, and the rod portion 2 And a reaction force unit 5 attached to the rod unit 2 and securing a reaction force to the rotation of the stirring unit 3.
With this configuration, there is no need to transmit the rotational driving force from the construction machine installed on the ground to the stirring unit 3, so ground improvement by mechanical agitation can be performed without increasing the size of the construction machine installed on the ground. it can. Since the construction machine installed on the ground becomes lightweight, the construction machine can be installed only by laying a plate having a large plane area on the ground, and the surface layer improvement is unnecessary. In addition, if the water depth of the ship can be obtained in the middle of the reclamation by the dredged soil, it will be possible to load the construction machine on the ship for construction.

Furthermore, in the present embodiment, the reaction force portion 5 includes a cylindrical demarcated frame 51 covering the stirring portion 3 and a plate-like reaction force wing 53 attached to the outside of the demarcated frame 51.
With this configuration,

Furthermore, in the present embodiment, the stirring unit 3 includes the shaft portion 31 rotatably supported by the rod portion 2 and a plurality of stirring blades 32 radially extending from the shaft portion 31. The jet nozzle 33 is a stirring blade 32 is formed.
By this configuration, the range in which the solidifying material and the soil are mixed by the stirring portion 3 is limited to the inner periphery of the defining frame 51, and the finished form of the improved body is defined.

Furthermore, in the present embodiment, a plurality of jets 33 having different distances from the central axis of the rod portion 2 are formed.
By this configuration, the solidifying material can be ejected uniformly into the ground.

Furthermore, in the present embodiment, the jet nozzle 33 is formed on the rear side in the rotational direction of the stirring blade 32.
By this configuration, since the solidifying material can be jetted into the soil stirred by the stirring blade 32, mixing of the solidifying material and the soil is promoted. Furthermore, the rotational driving force of the stirring unit 3 can be complemented by the ejection of the solidifying material.

Furthermore, in the present embodiment, the stirring power unit 4 includes a plurality of power sources 41 for driving the stirring unit 3 to rotate, and in the plurality of power sources 41, the mass distribution around the axis of the rod portion 2 is rotationally symmetric. It is attached to the rod part 2 so that it may become.
With this configuration, the stirring unit 3 can be rotated uniformly.

Furthermore, in the present embodiment, the helical wings 132, 152 generate thrust that travels downward or upward by rotation, and the propulsion is attached to the rod portion 2 and rotationally drives the helical wings 132, 152 by the supplied power. A power unit (lower propulsion power unit 14, upper propulsion power unit 16) is provided.
While being able to perform settlement of the ground improvement device 1a smoothly by this structure, the smaller lifting machine 9 can be employ | adopted.

Furthermore, according to the ground improvement method of the present embodiment, the lifting and lowering machine 9 for suspending the ground improvement device 1 by the hanging rope body 6 attached to one end of the rod portion 2 and the solidifying material supply device 10 for supplying the solidifying material to the stirring unit 3 And the power supply device 11 for supplying power (hydraulic energy) to the stirring power unit 4 on the target ground, and the lifting rope 9 sends out the hanging rope body 6 to sink the ground improvement device 1 to the target ground In the state, the solidifying material is supplied to the stirring unit 3 from the solidifying material supply device 10, and the motive power is supplied to the stirring power unit 4 from the power supply device 11, and the stirring portion 3 is The rotary drive is performed, and the improved body 12 is formed by mixing the solidifying material and the soil.
With this configuration, only by suspending the ground improvement device 1 by the lifting machine 9, there is no need to transmit the rotational driving force from the construction machine installed on the ground to the stirring unit 3, so the construction machine installed on the ground is large Ground improvement by mechanical agitation can be performed without Since the construction machine installed on the ground becomes lightweight, the construction machine can be installed only by laying a plate having a large plane area on the ground, and the surface layer improvement is unnecessary. In addition, if the water depth of the ship can be obtained in the middle of the reclamation by the dredged soil, it will be possible to load the construction machine on the ship for construction.

Furthermore, in the present embodiment, the improved body 12 is formed while the ground improvement device 1 sunk in the target ground is pulled up by the lifting machine 9.
Furthermore, in the present embodiment, during the settlement of the ground improvement device 1, power is supplied from the power supply device 11 to the stirring power unit 4 without supplying the solidifying material from the solidifying material supply device 10 to the stirring unit 3. , The stirring unit 3 is rotationally driven.
With this configuration, when the ground improvement device 1 is pulled up, the ground improvement device 1 can be smoothly pulled up on the same track as that of the settlement without causing the formed improved body 12 to become a resistance.

  The present invention is not limited to the above embodiments, and it is apparent that each embodiment can be appropriately modified within the scope of the technical idea of the present invention.

1, 1a Ground improvement device 2 Rod portion 3 Stirring portion 4 Stirring power portion 5 Reaction force portion 6 Hanging cord 7 Solidifying material supply hose 8 Hydraulic hose 9 Lifting machine 10 Solidifying material supply device 11 Power supply device 12 Improved body 13 Lower side Propelling part 14 Lower side propelling power part 15 Upper propelling part 16 Upper propelling power part 21 Base 22 Mounting part 23 Ejection port 31 Shaft part 32 Stirring blade 33 Jet port 34 Flow path 35 Communication groove 36 Internal gear 37 Hollow part 41 Power source 42 Power source fixing portion 43 Rotating shaft 44 Spur gear 51 Definition frame 52 Frame fixing 53 Reaction force wing 131 Lower shaft portion 132 Spiral wing 133 Spur gear 141 Power source fixing portion 143 Rotating shaft 144 Spur gear 151 Upper shaft portion 152 Spiral wing 153 Spur gear 161 Power source 162 Power source fixing portion 163 Rotating shaft 164 Spur gear

Claims (10)

Rod part,
A stirring portion rotatably supported by the rod portion and having a jet port for jetting out the supplied solidified material into the ground;
A stirring power unit attached to the rod unit and rotationally driving the stirring unit by the supplied power;
A ground improvement device comprising: a reaction force portion attached to the rod portion and securing a reaction force against rotation of the stirring portion. The reaction force portion is a cylindrical demarcated frame covering the stirring portion;
The ground improvement device according to claim 1, further comprising: a plate-like reaction blade attached to the outside of the frame. The stirring unit is a shaft portion rotatably supported by the rod portion.
And a plurality of stirring blades extending radially from the shaft portion;
The ground improvement device according to claim 1 or 2, wherein said jet nozzle is formed in said stirring blade.   The ground improvement device according to claim 3, wherein a plurality of the jet outlets different in distance from a central axis of the rod portion are formed.   The ground improvement device according to claim 3 or 4, wherein the jet nozzle is formed on the rear side in the rotational direction of the stirring blade. The stirring power unit includes a plurality of power sources for rotationally driving the stirring unit,
The ground improvement device according to any one of claims 1 to 5, wherein a plurality of power sources are attached to the rod portion such that mass distribution around the axis of the rod portion is rotationally symmetric. . A helical wing that generates a downward or upward propulsive force by rotation;
The ground improvement device according to any one of claims 1 to 6, further comprising: a propulsion power unit attached to the rod portion and configured to rotationally drive the spiral wing by the supplied power. A ground improvement method for improving a target ground using the ground improvement device according to any one of claims 1 to 7,
A lifting machine for suspending the ground improvement device by a hanging rope attached to one end of the rod portion, a solidifying material supply device for supplying a solidifying material to the stirring portion, and a power supply device for supplying power to the stirring power portion And on the target ground,
The solidifying material is supplied from the solidifying material supply device to the agitating unit in a state where the hanging rope body is sent out by the lifting machine and the ground improvement device is sunk to the target ground, and the power is supplied from the power supply device. A ground improvement method comprising: supplying an agitation power unit; rotating the agitation unit while ejecting the solidified material from the jet port; and forming an improved body by mixing the solidified material and soil.   9. The ground improvement method according to claim 8, wherein the improved body is formed while pulling up the ground improvement device sunk to the target ground by the lifting machine.   During the settlement of the ground improvement device, power is supplied from the power supply unit to the stirring power unit without supplying the solidifying material from the solidifying material supply device to the stirring unit, and the stirring unit is rotationally driven. The ground improvement method according to claim 9, characterized in that:

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