JP2001214431A - Ground improvement machine, method for improving groud, and multi pumping machine for compression transporting solidifying agent - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a ground improvement machine which enables smooth and reliable supply and jet of solidifying agents. SOLUTION: Corresponding to an improved rod 10 which has a plurality of jet holes 11, 11 leaving longitudinal spaces, a system for supplying solidifying agents, which is composed of pumping means 16 for compression transporting solidifying agents and a feeding route 17 transporting and supplying solidifying agents sent from pumping means 16 to jet holes 11, is provided independently to each jet hole 11. A multi pumping machine 20 is suitably used, of which the plural sending out sections 30 equivalent to pumping means 16 are driven by one driving source 42. In this case, each sending out section 30 is detachable independently and the number of sending out sections is made possible to be increased or decreased.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ground improvement apparatus and method particularly suitable for ground improvement from the ground surface or near the surface to a predetermined depth, and a solidified material pumping multipump apparatus suitable for these apparatuses and methods.

[0002]

2. Description of the Related Art One of the inventors of the present invention has been engaged in the invention of Japanese Patent Application No. 09-113386 described above as a ground improvement device of this kind. As shown in FIG. 11, the ground improvement apparatus includes an improvement rod 100 having a plurality of injection ports 101, 101,... Spaced apart in the longitudinal direction, a solidified material pumping means (not shown), and a pumping means provided by the pumping means. , And a supply path 102 for conveying and supplying the obtained solidified material to the injection ports 101, 101,..., And one solidification material supply system including a pump means and a supply path 102 is provided for all the injection ports 101, 101,. , And is configured to distribute and supply the solidifying agent pressure-fed from this one supply system to the plurality of injection ports 101, 101,. The illustrated example shows a state in which the solidifying material is supplied to the uppermost injection port 101 in the figure and is injected.

[0003]

However, as the experiment is repeated in the subsequent development process, the solidifying agent pressure-fed from one supply system is distributed and supplied to a plurality of injection ports while being sequentially switched as described above. However, since the pumping resistance is different for each injection port, it is not possible to maintain a uniform distribution amount (specifically, the lower the injection port, the larger the injection resistance and the larger the pumping resistance, so the injection amount is reduced). There was found.

[0004] Further, since the pumping force acts intermittently on each of the injection ports, the solidified material temporarily stays near the injection ports when the pumping force is not acting, so that the injection ports are blocked. It turned out to be.

[0005] Therefore, a main object of the present invention is to solve the above problems and to enable the smooth and reliable supply and injection of the solidified material.

[0006]

According to the present invention, there is provided an improved rod having a plurality of injection ports spaced apart in a longitudinal direction, and a pump for pumping a solidified material. And a supply path for conveying the solidified material sent from the pump means to the injection port, and improving the ground by injecting the solidified material from the injection port with the improved rod inserted into the target ground. In the apparatus, a solidification material supply system including the pump means and the supply path is provided independently for each injection port, and the solidification material supply to each injection port by the solidification material supply system is performed independently of each other. It is a ground improvement device characterized by the above.

According to a second aspect of the present invention, there is provided a means for moving the improved rod in a zigzag manner by inserting the improved rod into the ground accompanied by movement along the ground surface and pulling the improved rod. The ground improvement apparatus according to claim 1, wherein a plurality of stirring blades are provided in the vicinity, and a plurality of stirring and mixing sections each including an injection port and a stirring blade adjacent thereto are formed at intervals in the longitudinal direction.

According to a third aspect of the present invention, in the improved rod, at least the same number of pipes as the injection ports are bundled and integrated, and each of the pipes is provided independently of the supply port corresponding to each of the injection ports. The ground improvement device according to claim 1 or 2, wherein each of the roads is formed.

According to a fourth aspect of the present invention, there is provided an apparatus for improving the ground from a ground surface or a portion in the vicinity of the surface to a predetermined depth, wherein a slurry-based solidified material is supplied from an uppermost injection port closest to the ground surface and the remaining solidified material is discharged. The ground improvement device according to any one of claims 1 to 3, wherein a powder-based solidifying material is injected from the injection port.

According to a fifth aspect of the present invention, there is provided a multi-unit having at least the same number of delivery portions as cylinders and pistons, the cams for reciprocating the pistons, and a rotary drive source for rotating the cams. 2. A multi-pump device comprising a pumping pump device, wherein each of said delivery sections in said multi-pump device constitutes each said pumping pump means.
5. The ground improvement device according to any one of 4.

According to a sixth aspect of the present invention, there is provided an improved rod having a plurality of injection ports spaced apart in the longitudinal direction, a pump for pumping solidified material, and a method for supplying the solidified material delivered from the pump means to the injection ports. Using a ground improvement device having a supply path for conveying and supplying, in a method of improving the ground by injecting the solidified material from the injection port in a state where the improved rod is inserted into the target ground, the pump means and the supply path The solidification material supply system is provided independently for each injection port, and upon the improvement, the solidification material supply to each injection port by each of the solidification material supply systems is performed simultaneously and continuously, and simultaneously and individually from each injection port. It is a ground improvement method characterized by continuously injecting a solidifying material.

According to a seventh aspect of the present invention, a stirring blade is provided near each of the injection ports of the improved rod, and a stirring and mixing section comprising the injection port and each of the stirring blades adjacent thereto is spaced apart in the longitudinal direction. A plurality of holes are formed, and at the time of the improvement, while the improved rod is inserted into the ground accompanying movement along the ground surface and moved in a zigzag manner by pulling up, the solidified material is injected from each of the injection ports, and 7. The soil improvement method according to claim 6, wherein the agitated blade solidifies the injected solidified material and the in-situ soil, and sequentially forms and expands an improvement area for each of the agitation and mixing sections.

The invention according to claim 8 is the soil improvement method according to claim 7, wherein the improvement rod is moved in a zigzag manner such that the improvement areas formed by the stirring and mixing sections are continuous with each other. is there.

According to a ninth aspect of the present invention, there is provided a method for improving a ground from a ground surface or a portion in the vicinity of the surface to a predetermined depth. In the improvement, a slurry-based solidified material is discharged from an uppermost injection port closest to the ground surface. The ground improvement method according to any one of claims 6 to 8, wherein a powdered solidified material is injected from the remaining injection ports.

On the other hand, the invention according to claim 10 is a pump device for sucking solidified material into the cylinder and sending solidified material out of the cylinder by a piston reciprocating in the cylinder, comprising: a rotary drive source; A drive source side device having a camshaft rotated by the rotary drive source, and a cam attached to the camshaft; a plurality of delivery units each including a piston and a cylinder containing the same; And a sending section are arranged side by side on a base, and at least the sending section is detachably attached to the base, and when attached to the base, a piston of the sending section reciprocates by a corresponding cam. The solidification material pumping multi-pump device is characterized in that it is configured to be operated, and is configured to be able to increase or decrease the number of sending parts as needed. That.

According to an eleventh aspect of the present invention, each of the delivery portions is configured such that suction chambers are respectively formed in the forward and backward directions of the piston in the cylinder, and the forward movement of the piston is performed. At the same time, the solidified material in the suction chamber on the forward direction is sent out and the solidified material is sucked into the suction chamber on the backward direction at the same time. The solidified material pressure-feeding multi-pump device according to claim 10, wherein the solidified material is continuously delivered by sucking and introducing the solidified material into the suction chamber on the forward movement direction side at the same time. .

According to a twelfth aspect of the present invention, there is provided a suction path for sucking and introducing a solidified material from a solidified material supply source into one of the suction chambers. The suction path is provided with a first check valve, and the other suction chamber is provided with a suction and delivery path connecting the other suction chamber and the delivery path, In the delivery path, a second section is provided between a junction where the suction and delivery path merges with the delivery path and the one suction chamber.
Is provided, and when the solidified material sucked and introduced into the one suction chamber is sent out to the delivery path, half of the delivered solidified material is sucked into the other suction chamber via the suction and delivery path. The other half is sent out to the outside via the delivery path, and the solidified material in the other suction chamber is used to suck in the next new solidified material into the one suction chamber. 12. The suction chamber is configured to be sent out from the suction chamber to the outside via the suction / sending / using path and a delivery path portion downstream of the second check valve in this order.
It is a solidification material pumping multi-pump apparatus described in the above.

[0018]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. <About Ground Improvement Apparatus and Method> FIG. 1 shows a ground improvement apparatus example 1 according to the present invention. First, the outline of the improvement device 1 will be described.
A leader 5 is attached to the tip of an arm 4 attached to the front of the revolving base 2A via a boom 3, a lifting base 6 that moves up and down along the leader 5 is mounted, and a rod rotation drive source is mounted on the lifting base 6. 15 is attached, and the improved rod 10 includes:
By swinging the boom 3 and the arm 4 or moving the bogie 2 forward and backward, it can be moved (usually horizontally) along the ground surface, and is inserted into the ground G as the lifting base 6 moves up and down along the reader 5. The raising is possible.
In the figure, reference numeral 14 denotes a dust prevention hood, which is preferably attached when the ground from or near the surface to a predetermined depth is improved by using a powder solidification material. Further, a plurality of improved rods 10 can be provided side by side (for example, in a direction perpendicular to the plane of the drawing).

The improved rod 10 has a plurality of injection ports 11, 11 at predetermined stage intervals in the longitudinal direction, and stirring blades 12, 12,... Provided near each of the injection ports 11, 11, respectively. is there. Therefore, a plurality of stirring / mixing sections 13, 13 each composed of the injection port 11 and the stirring blades 12, 12,... Adjacent to the injection port 11, are formed at intervals in the longitudinal direction. In the illustrated example, in order to improve the stirring and mixing ability between the injected solidified material and the in-situ soil, each stirring and mixing unit 13 includes the stirring blade 1.
The upper and lower stages 2, 2,... Are provided, and the injection port 11 is formed in such a manner that the back side in the rotation direction of the lower stirring blade 12 is close to the side.

As shown in FIGS. 2 and 3, the apparatus 1 comprises a pumping means 16 for pressurizing the solidified material and a supply path 17 for conveying the solidified material delivered from the pumping means 16 to the injection port 11. The solidified material supply system is provided independently for each injection port 11. In the illustrated example, the number of tubes 18, 18 corresponding to the injection ports 11, 11 are bundled and integrated to form an improved rod body, and each of the tubes 18, 18 is formed.
Are connected to the corresponding injection ports 11, 11, respectively, and independent supply paths 17, 1 are provided by the pipes 18, 18.
7 are respectively formed. Each tube 18,
The base end of 18 is connected to the corresponding pumping pump means 16, 16 via extension connection pipes (not shown).

As the pumping means 16, 16, a solidification material pumping device such as a rotary pump or a piston pump can be provided individually for the injection ports 11, 11, but in that case, a pump driving source is included. The whole apparatus configuration requires the same number of the injection ports 11 and 11, and the apparatus becomes large in size and is not economical. Therefore, it is recommended to use a multi-pumping pump device capable of driving a plurality of delivery units with one drive source, and to configure each of the delivery units in the multi-pump device to constitute the respective pumping pump means 16, 16. (Not shown). This can minimize the size and cost of the device. Although a specific example of the multi-pump device will be described later, other known multi-pump devices can of course be used.

On the other hand, upon improvement, as shown in FIG.
In a state where the improved rod 10 is inserted into the target ground, the solidification material is simultaneously and continuously supplied to each of the injection ports 11, 11 by each solidification material supply system.
The ground G is improved by injecting the solidified material from 1 simultaneously and continuously. By providing the independent supply systems for each of the injection ports 11 and 11 in this way, the supply of the solidified material can be performed continuously, not intermittently, and the blockage unlike in the related art is less likely to occur. Injection port 11,
11 regardless of the difference in the pumping resistance of each
From 1 and 11, a predetermined amount of solidified material can be injected. As the solidifying material, either a powder-based material or a slurry-based material can be used.

In particular, by inserting the improved rod 10 into the ground accompanied by the movement along the ground G surface and pulling it up, the improved rod 10 is moved in a zigzag manner as shown by a two-dot chain line in FIG. It is preferable that the solidified material is jetted, and the jetted solidified material and the in-situ soil are stirred by the respective stirring blades 12, 12..., So that the improved region is sequentially formed and expanded for each of the stirring and mixing sections 13, 13. In this case, it is preferable that the improved rod is moved in a zigzag manner so that the respective improved regions formed by the respective stirring / mixing sections 13 and 13 are continuous with each other. The present invention also provides
As shown in the figure, it is particularly suitable for improving the ground from the ground surface G or a portion near the surface to a predetermined depth.

In the present invention, the solidified material injected from each injection port 11 can be made different. In this case, the material itself may be completely different for each of the injection ports 11 and 11, such as a powder system and a slurry system, or the physical properties such as the particle diameter may be different even if the same powder solidification material is used. Even a slurry-type solidified material can be made to have different physical properties such as viscosity. Further, as described above, the present invention is suitable for improving the ground from the ground surface G or a portion near the surface to a predetermined depth, but in that case, upon improvement, the uppermost injection port closest to the ground surface 11
When the slurry-based solidifying material is sprayed from the nozzle, and the powder-based solidifying material is sprayed from the remaining injection ports 11, the powder-based solidifying material is difficult to come out to the ground surface, so that dust can be prevented from being generated. Can be omitted.

<About the solidification material pumping multi-pump device>
5 and 6 show an example 20 of a multi-pump device according to the present invention.
It has a basic configuration including a plurality of delivery sections 30 each including a piston 1 and a piston 32, a cam 41 for reciprocating the piston 31, and a rotary drive source 42 for rotating the cam 41.

More specifically, a rotation drive source 42 is fixedly mounted on one end of the base 50, a cam support frame 43 is fixedly mounted in the center, and the cam support frame 43 is fixedly mounted.
A camshaft 44 is pivotally supported between the pair of end plates, and a required number of cams 41, 41,...
The phase is shifted according to the number of cams, and an endless chain 46 is wound around a sprocket 44A fixed to one end of the camshaft 44 and a sprocket 42B fixed to the rotating shaft 42A of the rotary drive source 42. ing.

Further, corresponding to each cam 41,
A cam follower tappet 47 in contact with the cam surface and a tappet case 48 for supporting the cam follower are provided, and each tappet case 48 is supported reciprocally with respect to the cam support frame 43 in a horizontal direction orthogonal to the cam surface. And a connecting shaft 49 on the opposite side of each tappet case 48 from the cam side.
These connecting shafts 49 are also reciprocally movable in the same direction as the cam follower tappet 47 and the case 48 reciprocate, and the end of each connecting shaft 49 opposite to the follower tappet connecting side is a cam. It projects from the support frame 43. The portion from the rotary drive source 42 to the connection shaft 49 constitutes the drive source side device 40 of the present invention.

On the other hand, a delivery section mounting frame 45F is fixed to the other end side of the base 45, and a plurality of delivery sections 30 including a piston 32 and a cylinder 31 containing the piston 32 are detachably mounted on the frame 45F. Installed.
Piston rod 32R of piston 32 of each delivery section 30
Are detachably connected via a connecting member 50 to a connecting shaft 49 reciprocated by a corresponding cam 41. Accordingly, each sending section 30 is mounted at a predetermined position so as to enable such connection, for example, to be coaxial as shown. As shown in FIG. 6 (not shown in FIG. 5), a flange portion 50F is formed on the outer peripheral surface of each connecting member 50, and a corresponding cylinder 31 end flange portion 31F has a corresponding portion. Piston 32,
A biasing means 51 such as a coil spring that biases the connection shaft 49, the tappet case 48, and the tappet 47 toward the cam surface is sandwiched.

Thus, by operating the rotary drive source 42, the camshaft 44 and the respective cams 41 are integrally rotated via the chain 46, and the tappets 47 pressed against the respective cam surfaces correspond to the corresponding tappet cases. 4
8 and the connecting shaft 49 are reciprocated.
The piston 32 is also reciprocated via the piston rod connected to the piston 9.

In particular, it is preferable that the cam 41 has a predetermined shape such that the stroke of the piston 32 is a linear motion at a constant speed, for example, a predetermined heart shape. Specifically, as shown in FIG. 7, the heart-shaped cam 41 is such that the displacement e per unit rotation angle is always constant. If the displacement e per unit rotation angle is always constant in this way, the stroke of the piston 32 becomes a constant-speed linear motion, and each of the sending units 30 can always discharge at a constant amount (namely, constant supply).

Characteristically, the drive source side device 40 and the plurality of sending sections 30 are separately provided side by side on a base 45, and at least the sending sections 30 are individually detachably attachable to the base 45. And the piston 32 of the delivery unit 30 is reciprocated by the corresponding cam 41 when attached to the base 45.
Although 0 is the same as the number of the cams 41, the number of the sending sections 30 can be increased or decreased as necessary. With such a configuration, for example, when used in the above-described ground improvement apparatus 1, the sending unit 30 may be installed at a site or the like in accordance with the number of solidification material supply systems of the apparatus 1 as necessary.
Can be increased or decreased, and one pump device 20 can cope with various operations in which the number of solidification material supply systems is different.

Next, the details of each delivery section 30 will be described. As can be seen from the backward movement start state shown in FIG. 8 and the forward movement start state shown in FIG. Suction chamber 33 on the reversing direction side
A and 33B are formed respectively. When the piston 32 moves forward, the suction chamber 33 on the forward movement direction side is formed.
At the same time as the solidified material in A is sent out, the solidified material is sucked and introduced into the suction chamber 33B in the backward direction, and conversely, the solidified material in the backward direction suction chamber 33B is sent out in the backward direction. At the same time, the solidified material is sucked and introduced into the suction chamber 33A on the forward movement side, so that the solidified material is continuously delivered.

For this reason, in the illustrated example, the forward side suction chamber 33A
On the other hand, a suction path 34 for sucking and introducing the solidified material from a solidified material supply source such as a solidified material storage tank (not shown) into the suction chamber 33A, and a delivery path 35 for sending the sucked solidified material.
And one suction chamber 33 </ b> A in the suction path 34.
A first check valve 38 is provided near the inlet to the suction port, and the return-side suction chamber 33B is provided for the return-side suction chamber 33B.
A suction and delivery path 36 connecting the inside and the delivery path 35 is provided, and a second section of the delivery path 35 between the junction 37 where the suction and delivery path 36 joins the delivery path 35 and one suction chamber 33A. A check valve 39 is provided. Also, the return side suction chamber 33
B, taking into account the existence of the piston rod 32R, the suction amount of the backward suction chamber 33B
It is designed to be half of the suction amount of 3A.

With this configuration, when the solidified material sucked and introduced into the forward side suction chamber 33A by the forward movement of the piston 32 is sent out to the sending path 35, as shown in FIG. 9, half of the solidified material sent out is sucked. It is sucked into the return side suction chamber 33B via the sending-out path 36, and the other half is sent out through the sending-out path 35 to the outside. At this time, the first check valve 38 is closed to prevent the backflow to the suction passage 34. The solidified material sucked into the reversing-side suction chamber 33B is then downstream from the reversing-side suction chamber 33B from the suction and delivery path 36 and the second check valve 39 at the time of resuming shown in FIG. In this case, the solidified material sent out from the suction / sending / using path 36 by the second check valve 39 flows back into the forward side suction chamber 33A. Is prevented, and the next new solidified material is moved to the forward side suction chamber 3.
It is sucked into 3A. Thus, it is possible to supply the solidified material to each of the predetermined destinations continuously and constantly at a constant rate for each of the sending units 30.

On the other hand, in the above example, the delivery section 30 is provided on only one side of one cam 41, but, for example, as shown in FIG. Alternatively, a so-called horizontally opposed arrangement may be adopted in which the delivery section 300 is fixed at an appropriate position such as the lower side and the delivery section 300 is also arranged on the base 45 on the other side of the cam 41. In this case, the opposite sending units have a phase of 180 degrees. And even if it is the same installation area, it becomes possible to drive more sending units by one drive source 42.

[0036]

As described above, according to the present invention, the solidified material can be smoothly and reliably supplied and injected.

[Brief description of the drawings]

FIG. 1 is a side view showing an example of a ground improvement device according to the present invention.

FIG. 2 is a partial cross-sectional front view showing an improved rod portion of an example of a ground improvement device according to the present invention.

FIG. 3 is a sectional view taken along the line III-III of FIG. 2;

FIG. 4 is a longitudinal sectional view showing an outline of a ground improvement method according to the present invention.

FIG. 5 is a partially sectional plan view showing an example of a multi-pump device according to the present invention.

FIG. 6 is a partial cross-sectional front view showing an example of a multi-pump device according to the present invention.

FIG. 7 is an explanatory diagram of a cam used in the multi-pump device according to the present invention.

FIG. 8 is an enlarged view of a main part of a partial cross section showing a sending section.

FIG. 9 is an enlarged view of a main part of a partial cross section showing a sending section.

FIG. 10 is a partial sectional front view showing another example of the multi-pump device according to the present invention.

FIG. 11 is an explanatory view of a conventional ground improvement device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Ground improvement apparatus, 10 ... Ground improvement rod, 11 ... Injection port, 12 ... Stirring blade, 13 ... Stirring / mixing part, 16 ... Pump means, 17 ... Supply path, 18 ... Pipe, 20 ... Multi pump apparatus, 40 ... Drive source side device, 41: cam, 42: rotary drive source, 30: delivery unit, 31: cylinder, 32: piston.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Kazuhiro Watanabe 1-10-6 Taito, Taito-ku, Tokyo F-term in BM System Co., Ltd. 2D040 AB03 BA08 BA13 BC00 CB01 CB03 CD03 DA02 DA12 DB07 EA18 EA21

Claims (12)

[Claims] An improved rod having a plurality of injection ports spaced apart in a longitudinal direction, a pumping means for pumping solidified material, and a supply passage for conveying the solidified material delivered from the pump means to the injection ports. A device for improving the ground by injecting the solidification material from the injection port with the improved rod inserted into the target ground, wherein a solidification material supply system comprising the pump means and a supply path is provided independently for each injection port. And a solidification material supply system configured to supply the solidification material to each of the injection ports by the solidification material supply system independently of each other. Means for inserting the improved rod into the ground with movement along the ground surface and moving the improved rod in a zigzag manner by pulling up the improved rod, and stirring blades near each of the injection ports in the improved rod. The ground improvement apparatus according to claim 1, wherein a plurality of agitating and mixing sections each including an injection port and an agitating blade adjacent thereto are formed at intervals in a longitudinal direction. 3. The improved rod includes at least the same number of pipes as the injection ports are bundled and integrated, and each of the pipes forms the independent supply path corresponding to each of the injection ports. 3. The method according to claim 1, wherein
The ground improvement device as described. 4. An apparatus for improving the ground from a ground surface or a portion in the vicinity of the surface to a predetermined depth, wherein a slurry-based solidified material is supplied from an uppermost injection port closest to the ground surface, and a powder-based material is supplied from the remaining injection ports. The ground improvement device according to any one of claims 1 to 3, wherein the solidification material is injected. 5. A multi-pressure feed pump device having at least as many delivery units as cylinders and pistons, the number of which is equal to the number of the injection ports, a cam for reciprocating the pistons, and a rotary drive source for rotating the cams. The ground improvement device according to any one of claims 1 to 4, wherein each of the delivery units in the multi-pump device forms each of the pressure pump units. 6. An improved rod having a plurality of injection ports spaced apart in the longitudinal direction, pumping means for pumping the solidified material, and a supply path for conveying the solidified material delivered from the pump means to the injection ports. In a method of improving the ground by injecting a solidified material from the injection port in a state where the improved rod is inserted into the target ground, using a ground improvement device having a solidified material supply system including the pump means and a supply path. Independently provided for each injection port, upon improvement, the solidification material supply to each injection port by each solidification material supply system is performed simultaneously and continuously, and the solidified material is simultaneously and continuously continuously output from each injection port. A ground improvement method characterized by spraying. 7. A stirrer is provided near each of said injection ports in said improved rod, and a plurality of stirrer / mixer sections each comprising an injection port and a stirrer adjacent thereto are formed at intervals in the longitudinal direction, At the time of the improvement, the solidification material is injected from each of the injection ports, and the injection rod is solidified by the stirring blades while the improved rod is inserted into the ground along with the ground surface and moved in a zigzag manner by pulling up the improved rod. The soil improvement method according to claim 6, wherein the material and the in-situ soil are agitated, and an improvement area is sequentially formed and expanded for each of the agitation and mixing sections. 8. The ground improvement method according to claim 7, wherein the improvement rod is moved in a zigzag manner such that the improvement areas formed by the stirring and mixing sections are continuous with each other. 9. A method for improving the ground from the surface of the ground or a portion in the vicinity of the surface to a predetermined depth, wherein in the improvement, a slurry-based solidified material is supplied from an uppermost injection port closest to the ground surface, and a remaining injection port is provided. The ground improvement method according to any one of claims 6 to 8, wherein a powder-based solidifying material is injected from the ground. 10. A pump device for sucking solidified material into a cylinder and sending solidified material out of a cylinder by means of a piston reciprocating in the cylinder, comprising a rotary drive source and a rotary drive source. A camshaft,
A drive source-side device having a cam attached to the camshaft; a plurality of delivery units each including a piston and a cylinder containing the same; and the drive source-side device and the delivery unit are juxtaposed on a base. At least the sending section is configured to be detachable from the base, and that the piston of the sending section is reciprocated by the corresponding cam when attached to the base; Characterized in that it is configured to be able to increase or decrease as necessary. 11. Each of the delivery portions is configured such that suction chambers are respectively formed in a forward movement direction side and a backward movement direction side of the piston in the cylinder, and when the piston moves forward, the suction chamber is formed in the forward movement direction side. At the same time as the solidified material in the suction chamber is delivered, the solidified material is suction-introduced into the suction chamber on the reversing direction side. The solidification material pumping multi-pump device according to claim 10, wherein the solidification material is continuously delivered by suctioning the solidification material into the suction chamber on the movement direction side. 12. A suction path for sucking and introducing a solidified material from a solidified material supply source into one of the suction chambers, and a delivery path for sending out the sucked solidified material. The suction path is provided with a first check valve, and the other suction chamber is provided with a suction and delivery path connecting the other suction chamber and the delivery path. A second check valve is provided between the junction where the suction and delivery path merges with the delivery path and the one suction chamber, and the solidified material sucked and introduced into the one suction chamber is delivered to the delivery path. At this time, half of the delivered solidified material is sucked into the other suction chamber via the suction / sending / use path, and the other half is sent out via the delivery path,
When the next new solidified material is sucked and introduced into the one suction chamber, the solidified material in the other suction chamber is higher than the suction / delivery path and the second check valve from the other suction chamber. The solidification material pressure-feeding multi-pump device according to claim 11, wherein the solidification material pressure-feeding multi-pump device is configured to be sent to the outside through a downstream delivery path portion in this order.