JP2003027458A - Method for soil improvement - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for soil improvement, which can reduce the number of created underground consolidated bodies while maintaining accuracy and strength, which are required for the underground consolidated body. SOLUTION: This method comprises: a crossing jet using process for creating the first underground consolidated body (1) having radial dimensions controlled with high accuracy by making a solidification material (S) jetted while constituting a crossing jet (J); and a horizontal jet using process for creating the second underground consolidated body (2) by emitting a horizontal jet (J2 ) of the solidification material (S) in an area between the consolidated bodies (1) created in the crossing jet using process.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solid material injection means that penetrates into the ground, injects a jet of solidification material from the solidification material injection means, and rotates the solidification material injection means while pulling it up to the ground side to form a circle. A ground improvement method that creates a pillar-shaped underground solid and constructs an underground structure with the multiple underground solids that have been formed, and a preceding underground beam and a stop by the underground solid that has been created. The present invention relates to a ground improvement method for constructing a solid for water.

[0002]

2. Description of the Related Art In a conventional ground improvement method, as shown in FIG. 18, a plurality of underground solid bodies having the same radial dimension are formed by using a cross jet which controls the radial dimension with high accuracy. However, it was to construct an underground structure, a preceding underground beam and a solid body for water stoppage.

However, when the above-mentioned cross jet is used, the radial dimension is highly accurate, but the radius of the underground consolidate cannot be increased, so that the number is large, resulting in a long construction period and cost. It was expensive.

[0004]

DISCLOSURE OF THE INVENTION The present invention has been proposed in view of the above-mentioned problems of the prior art, and as described above, the underground structure and the preceding underground beam are formed by the cylindrical solidified body. And a ground improvement method for constructing a solid body for waterproofing,
Providing a ground improvement method that can reduce the number of ground solidified bodies while maintaining the accuracy and strength required for the ground solidified bodies.

[0005]

According to the ground improvement method of the present invention, the solidifying material injection means is penetrated into the ground, the jet of the solidifying material is injected from the solidifying material injection means, and the solidifying material injection means is rotated. In the ground improvement method of pulling up to the ground side to form a columnar underground solidified body and constructing an underground structure from the formed multiple underground solidified bodies, the solidifying material (S) is a cross jet (J1 ) Is formed and the first submerged solidified body (1) which is injected with high precision is controlled in the radial direction, and the submerged consolidating step formed by the cross submerged consolidating step (1) is formed. Injection of solidified material in the horizontal direction in the area between the bodies (1) (J2)
And using a horizontal jet flow for forming a second solidified body (2) (claim 1). In addition, it is also possible to form an underground beam by the first underground solidified body (1) and the second underground solidified body (2).

According to the ground improvement method of the present invention having such a configuration, the first underground solidified body (1) described above has a cross jet flow whose jet reach distance (L1) is controlled with extremely high accuracy. Since it is formed by using (J1), its radial dimension (R1) can be controlled with extremely high accuracy. Therefore, when constructing an underground structure, a portion where the radial dimension accuracy (R1) of the underground solidified body (1) is required to be highly accurate, for example, a portion corresponding to the contour, is the above-mentioned first. The solidified body (1) may be formed.

On the other hand, regarding the region surrounded by the first underground solid (the region (2) between the underground solids formed in the cross jet use process), the first underground solid If it reaches (1), highly precise control of the reaching distance of the solidified material jet is not required. Therefore, the solidified material may be jetted by the horizontal jet (J2) having a long reach (L2) but low control accuracy of the reach (L2) (horizontal jet (J2) use step).

Here, since the solidified material reaching distance (L2) by the horizontal jet (J2) is much longer than that when the cross jet is used, an underground solid body (J2) formed by the horizontal jet (J2) is used. The radial dimension (R2) of 2) also becomes longer. Then, as a result of the radial direction dimension (R2) of the underground solidified body (2) becoming long, the number of underground solidified bodies required to cover an area of a predetermined size can be reduced.

Further, in the ground improvement method of the present invention, the solidifying material jetting means (31, 32) is inserted into the ground, and the jet of the solidifying material (S) is jetted from the solidifying material jetting means (31, 32). While rotating the solidifying material injection means (31, 32), it is pulled up to the ground side (GL) to create a cylindrical solidified body (1), and the ground solidified body (1) thus formed is used to advance the ground. Middle beam (1
0) and the ground improvement method for constructing the water blocking solid (20), the solidifying material is injected while forming a cross jet (J21, J22) to control the radial dimension (R1) with high precision. The step of using the cross jet to create the underground beam (10), and the solidification material (S) is horizontally jetted (J2) between the preceding underground beams (10) to create the water blocking solid (20). It has a horizontal jet use process, and
(Claim 2).

According to the ground improvement method of the present invention having such a configuration, the preceding underground beam (10) has the jet reach distance (L1).
Is formed by using a cross jet (J) that is controlled with extremely high precision, so that its radial dimension (R1) can be controlled with extremely high precision. On the other hand, in the area between the rows of the preceding underground beams (10) (the area between the preceding underground beams), since the reaching distance (L2) of the solidified material jet (J2) is not required to be controlled with high accuracy, the reaching distance is reached. (L2) is long, but the control accuracy of the reaching distance (L2) is low, and the solidified material is injected by the horizontal jet (J2) (horizontal jet use step). As a result, the number of underground solidified bodies required to cover the region between the rows of the preceding underground beams (the region between the preceding underground beams) can be reduced.

In implementing the present invention, the cross jet used in the cross jet use step is a rod or a pair of nozzles (N11, N12) provided in the solidifying material jetting means (3). Jet (J11,
It may be configured by J12). Alternatively, the injection is performed from the rod or the nozzles (N21, N22) (solidification material injection means) provided at the tip of each of at least one pair of upper and lower stirring blades (M11, M12) provided in the solidification material injection means (31). It may be configured by a pair of jets (J21, J22) that perform

In carrying out the present invention, between the cross jet use step and the horizontal jet use step, the cross jet use solidifying material injection means (3, 31) to the horizontal jet use solidifying material injection means (33). , 32) is preferably carried out (claim 3).

Alternatively, the solidifying material jetting means comprises at least a pair of solidifying material jetting nozzles (N41, N42), the jetting angle of the nozzles (N41, N42) is variable, and the cross jetting step and the horizontal jetting step are used. Between the step and the step, it is preferable to execute an injection angle changing step for changing the injection angle of the nozzles (N41, N42) so as to be ejected in a horizontal direction from an angle (α) at which a pair of jets intersect. (Claim 4).

Further, in the injection angle changing step, it is preferable that no solidification material is injected from any one nozzle (N82) of at least one pair of solidification material injection nozzles (N81, N82). Specifically, for example, the flow path communicating with one nozzle may be closed by a ball valve V or the like.

Further, in carrying out the present invention, the solidifying material jetting means comprises at least a pair of crossing jetting solidifying material jet nozzles (N52, N53) and at least one horizontal jetting solidifying material jet nozzle (N51). ), The first solidifying material flow path (t) communicating with the solidifying material injection nozzles (N52, N53) for the cross jet in the cross jet using step.
o) is opened, and the solidified material injection nozzle (N
51) the second solidifying material flow path (ti) is closed, and in the horizontal jet use step, the first solidifying material communicating nozzles (N52, N53) for cross jets are connected. The second flow path (t) for the solidifying material, which closes the flow path (to) and communicates with the solidifying material injection nozzle (N51) for the horizontal jet.
Preferably, it is configured to open i) (claim 6).

In this case, a plurality of ball valves (BVi, B
Vo) is simultaneously moved up and down by, for example, the rod (100) and the drive device (102) for vertical movement, the ball valve is seated on the valve seat portion to close the flow passage, and the ball valve is separated from the valve seat portion. Therefore, it is preferable that the flow path is opened.

[0017]

DETAILED DESCRIPTION OF THE INVENTION A first embodiment of the present invention will be described below with reference to FIGS. In FIG. 1, an A (upper) portion sectioned by a horizontal line n shows a plan view, and a B (lower) portion shows a sectional view. First, the first solidified material injection unit 31 is penetrated into the ground to inject the solidified material S while forming the cross jet J to form the first underground solid body 1 in which the radial dimension is controlled with high accuracy. Create. Next, the second solidifying material ejecting means 32 is penetrated into the ground, and the second solidifying material ejecting means 32 injects the solidifying material by the horizontal jet flow to form the second underground solidified body 2. To do.

Further, the difference between the solidified material injection by the cross jet and the solidified material injection by the horizontal jet will be described in detail with reference to FIGS. First solidifying material jetting means 31 forming a cross jet
In the lower part of the central axis 31A constituted by the tubular body, the tubular body is constituted by the tubular body as shown in FIG.
A pair of upper and lower stirring blades M11 and M12 having a horizontal axis are provided horizontally in the drawing. In FIG. 1, the stirring blade M1
The loci of 1 and M12 are represented by the symbol C.

The nozzles N21 and N22 are the nozzles N2.
The nozzle angles are set so that the jet streams J21 and J22 jetted from the nozzles No. 1 and N22 intersect at the horizontal distance L1 from the nozzle tip. Therefore, the solidified material S pressure-fed by the pressure-feeding means (not shown) is the stirring blades M11, M12.
To the nozzles N21,
It is injected from N22. As another example of the first solidifying material ejecting means forming the cross jet, as shown in FIG. 2, the stirring blade is omitted and the pair of upper and lower nozzles N11 and N12 are first
31A of the solidified material injection means 31
It is also possible to attach directly to. 2, J11, J
Reference numeral 12 denotes a jet flow where the horizontal distance from the nozzle tip intersects at the point L12.

Next, as shown in FIG. 4, below the central axis 32A of the second solidifying material injection means 32 for generating a horizontal jet, which is composed of a tubular body, the tubular body is made up of a tubular body and nozzles N
The stirring blades M2 having N2 and N2 are horizontally provided in the figure. In FIG. 1, the trajectory of the stirring blade M2 is indicated by the symbol D.

The solidified material S pressure-fed by a pressure-feeding means (not shown)
Is a jet flow J2 from the nozzle N2 provided at the tip of the stirring blade M2, and the solidifying material S reaches a distance L2 from the nozzle.
Squirt out.

As another example of the second solidifying material jetting means for generating a horizontal jet, as shown in FIG. 5, the stirring blade is omitted and the nozzle N3 is directly connected to the pipe body 33A of the second solidifying material jetting means 33. It is also possible to attach to. In FIG. 5, J3 represents the jet of the solidified material S reaching the horizontal distance L2 from the nozzle tip.

FIG. 6 and FIG. 7 are, for example, planes when an underground structure is constructed so as to surround one second underground solid body 2 with twelve first underground solid bodies 1. And a vertical section. Referring also to FIG. 1, the diameter 2R1 of the first underground solidified body 1 has the jets J21 and J
22 is a value obtained by adding the injection distance L1 of the cross jet J from the nozzle N21, that is, the radius R1 is doubled. The diameter 2R2 of the second underground solidified body 2 is a value obtained by adding the injection distance L2 of the jet J2 from the nozzle N21 to the radius K2 of the stirring blade M2, that is, the radius R2 is doubled. The other parts have the same names and signs as those in FIG.

Although the ratio of the number of the first underground solid bodies surrounding the second underground solid bodies is different from that of FIGS.
As an example, K1 = 0.5 m, L1 = 0.5 m, K2 =
1.0m, L2 = 1.7m, that is, R1 = 1.0m, R2
= 2.7m.

FIGS. 8 and 9 show a first underground solid body 1 formed by a cross jet of solidifying materials and a second underground solid body 2 formed by a horizontal jet of solidifying materials. It is a figure showing the plane and longitudinal section of the underground structure constructed by. Figure 8
As is clear from the above, the first underground solids 1 are connected to each other, or the first
The underground solid body 1 and the second underground solid body 2 are overlapped with each other, and the underground solid body 2 is made to enter below the underground solid body 1 to flow at W in FIG. The porosity indicating the direction of is completely prevented from leaking upward from the constructed underground structure. 8 and 9, GL is the ground surface, C is the trajectory of the stirring blade when forming the first underground solidified body 1, and D is the stirring when forming the second underground solidified body 2. Shows the trajectory of the wings. Further, a part of the locus C of the stirring blade for the first underground solidified body is omitted.

According to the ground improvement method of the present invention having the above-mentioned structure, the above-mentioned first underground consolidated body 1 uses the cross jet J in which the jet reach distance L1 is controlled with extremely high accuracy. Since it is formed, the radial dimension R1 can be controlled with extremely high precision. Therefore, when constructing an underground structure,
For the location where the radial dimension R1 of the underground solid 1 is required to be highly accurate, for example, the location corresponding to the contour, the first underground solid 1 may be formed.

On the other hand, in the area surrounded by the first underground solid body 1, if the first underground solid body 1 is reached, the reach distance of the solidifying material jet is controlled with high precision. Is not required. Therefore, the solidified material S may be jetted by the horizontal jet flow J2 having a long reach distance but low reach distance control accuracy.

Here, the solidified material S by the horizontal jet J2
Since the reaching distance L2 is much longer than when the cross jet is used, the radial dimension R2 of the second underground solidified body 2 formed by the horizontal jet J2 also becomes long. Then, as a result of the radial dimension R2 of the underground solid body 2 becoming longer, it is possible to reduce the number of underground solid body formations required to cover a region of a predetermined size.

A second embodiment of the present invention is shown in FIGS.
It will be described based on 1. FIG. 10 and FIG. 11 show the preceding underground beam 10 which is a connection body of the first underground solidified body 1 formed by the cross jet of the solidifying material and the second underground beam 10 formed by the horizontal jet of the solidifying material. It is a figure which shows the plane and longitudinal cross section of the underground structure constructed | assembled with the solidification body 20 for waterproofing which is the connection body of the underground solidified body 2.

The ground improvement method according to the second embodiment is basically the same as that of the first embodiment described above, except that a certain area or a certain width is consolidated in the first cylindrical ground. A plurality of leading underground girders 10 which are aggregates of the body 1 are arranged, and a water blocking solid 20 is filled so as to fill the space between the preceding leading girders 10 and 10 adjacent to each other with the second underground solids 2. Is to build.

In FIG. 10, the earth pressure P1 acts on the area sandwiched between the steel sheet piles indicated by Q in the top and bottom of the paper, and in FIG. 11, the earth pressure is excavated up to H1. The earth pressure P2 acts from the bottom of the construction area to the top. Therefore, the height H2 of the preceding underground beam whose construction start surface is the depth H1 from the ground surface GL is set high enough to withstand the earth pressure P1, and the thickness T of the water blocking solid 20 is set to the earth pressure P2 from below. The value should be sufficient.

According to the ground improvement method of the present invention having such a structure, referring to FIG. 1 as well, the preceding underground beam 10 (corresponding to 1 in FIG. 1) has an extremely high jet reach distance L1. Since it is created by using the controlled cross jet J, its radial dimension R1 can be controlled with extremely high precision. On the other hand, in the region between the rows of the preceding underground beams 10 (corresponding to 1 in FIG. 1) (the region between the preceding underground beams), since the reaching distance L2 of the solidifying material jet J2 is not required to be controlled with high precision, The solidified material is jetted by a horizontal jet J2 having a long reach L2 but low control accuracy of the reach L2. This allows
It is possible to reduce the number of underground solidified bodies required to cover the region between the rows of the preceding underground beams 10.

In the first and third embodiments of the present invention, when the process of using the cross jet is changed to the process of using the horizontal jet in FIGS. 1 and 7, for example, the first solidifying material for the cross jet is used. The jetting means 31 is replaced with a second solidifying material jetting means 32 for horizontal jet, for example.

A third embodiment of the present invention will be described with reference to FIGS.
It will be explained based on. As shown in FIG. 12, the solidifying material ejecting means 34 includes a central shaft 34A composed of a tubular body and a central shaft 34A.
In the lower part of A, a pair of upper and lower stirring blades M31 and M32 orthogonal to the central axis 34A are provided horizontally in the drawing. At the tips of the stirring blades M31 and M32, a pair of angle-variable nozzles N41 and N42 each having a rotation axis in the direction perpendicular to the paper surface are provided.

When it is desired to form a cross jet with the variable angle nozzles N41 and N42, the jets J41 and J42 intersect at a predetermined horizontal distance L from the nozzle tip as shown in FIG. Further, when it is desired to make the jets in the horizontal direction, as shown in FIG. 14, the nozzles N41, J422 are arranged by means not shown so that the jets J411, J422 become horizontal.
It is configured to adjust the angle of N42. 12 to 14, the arrow S indicates the direction of the solidifying material flowing in the pipe.

Therefore, in the ground improvement method of the present invention using the solidifying material spraying means having the variable angle nozzle, there is no need to replace the solidifying material spraying means in the cross jet process and the horizontal jet process, and both the equipment and the time are required. Can be compressed and has high cost merit.

The fourth embodiment of the present invention will be described with reference to FIGS.
It will be explained based on. The present embodiment is configured such that the solidifying material is not jetted from any one of the solidifying material jetting means having the variable angle nozzle described above.

In FIG. 15, the solidifying material injection means 36 is
A central axis 36A composed of a tubular body, and a pair of upper and lower stirring blades M41 orthogonal to the central axis 36A at the lower part of the central axis 36A,
M42 is provided horizontally on the left and right in the drawing. The central axis 3
6A has a single tube To1, and stirring blades M41, M4
It communicates with 2.

A variable angle nozzle N81 similar to that of the fourth embodiment is provided at the tip of the stirring blade M41, and a pair of left and right nozzles N82 with fixed injection angles are provided at the tip of M42. A branch point T between the single tube TT and the stirring blade M42.
A ball valve V that blocks the flow SF20 of the solidifying material is configured to come into contact with the corner of o2 as necessary.

The ball valve V is connected to the driving device 75 via a connecting rod 76 and is vertically movable.

According to the ground improvement method of the present invention having such a structure, when it is desired to form a cross jet, the nozzle N81 keeps a predetermined angle β by means not shown (the nozzle N82 keeps the angle β at all times). The ball valve V is opened. Therefore, the divided flow SF10 of the solidifying material is inside the stirring blade M41, and the divided flow S of the solidifying material is inside the stirring blade M42.
F20 will flow in and will form a cross jet.

When a horizontal jet flow is desired, the nozzle N81 becomes horizontal by means not shown and the ball valve V is pushed up by the drive unit 75. The ball valve V pushed up contacts the corner of the branch point To2, the flow path is closed, the flow SF20 of the solidifying material is blocked, and the horizontal nozzle N81 forms a cross jet as shown in FIG. On the other hand, a jet flow J811 having a double flow rate is injected.

A fifth embodiment of the present invention will be described with reference to FIGS.
It will be explained based on. The solidifying material injection means 35 is composed of a central axis 35A made of a tubular body, and three stirring blades M51, M52 made of a tubular body and orthogonal to the central axis 35A below the central axis 35A.
It is composed of M53 and nozzles N51, N52, N53 provided in pairs at the tips of the stirring blades M51, M52, M53.

Referring to FIG. 17 as well, the central shaft 35A has an outer pipe To and an inner pipe T up to the stirring blade M51.
It is composed of a double pipe TT having i, and a single pipe To1 is provided below the stirring blade M51. The flow path t is provided in the double pipe TT.
o and ti are formed, and the flow passage to has the stirring blades M52 and M53.
The flow path ti communicates with the stirring blade M51.

Here, the flow path to corresponds to the "first solidifying material flow path communicating with the solidifying material injection nozzles (N52, N53) for the cross jets", and the flow path ti is "the horizontal jetting liquid. It corresponds to the "second solidifying material flow path" communicating with the solidifying material injection nozzle (N51).

The direction of the pair of nozzles N51 is fixed in the horizontal direction. On the other hand, the two pairs of nozzles N52, N
53 is a jet flow J52 jetted from the nozzles N52 and N53
The nozzle angle is set so that the horizontal distance from the nozzle tip to J53 intersects at the point L22.

Therefore, the solidifying material S pressure-fed by the pressure-feeding means (not shown) flows into the stirring blades M51, M52, M53 as branch flows SF51, SF52, SF53, respectively, and becomes a horizontal jet from the nozzle N51. Also, a cross jet is jetted from N52 and N53.

Here, a mechanism for complementarily opening and closing the flow paths ti, to is shown in FIGS.

Although the flow path to is open in FIG. 20,
The state where the flow path ti is closed is shown. In FIG. 20, the ball valve BVi is seated on the valve seat portion VSi in the vicinity of the branch point where the flow path ti branches into the nozzles N51 and N51, and the flow path ti is closed. On the other hand, the ball valve BVo is not seated in the valve seat portion VSo provided in the portion where the annular outer pipe to becomes a normal single pipe,
As indicated by the arrow SFo, the solidifying material is the nozzles N52 and N5.
2, N53, N53.

The ball valves BVi and BVo are connected to the rod 100.
And is moved up and down as the driving device 102 moves the rod 100 up and down. Therefore, when the rod 100 is moved downward (in the direction of arrow D in FIG. 21) from the state shown in FIG. 20, the state shown in FIG. 21 is obtained. That is, the ball valve BVo is seated on the seat portion VSo and the flow path t
Since o is closed, the cross jet is not injected. On the other hand, since the ball valve BVi is separated from the seat portion VSI to open the flow path ti, the solidifying material flowing through the flow path ti is indicated by the arrow SF5.
As indicated by 1, the nozzle N51 is supplied. Note that FIG.
To switch from the state 1 to the state of FIG. 20, the rod 1
00 may be moved upward (direction of arrow U in FIG. 20).

In the ground improvement method of the present invention using the solidifying material injection means having the above-mentioned structure, it is not necessary to replace the solidifying material injection means in the cross jet process and the horizontal jet process, and the equipment,
Both time can be reduced and the cost merit is high.

The illustrated embodiment is merely an example,
It is additionally noted that it is not intended to limit the technical scope of the present invention. For example, in the illustrated embodiment, the jet flow is jetted in two directions, but it may be jetted in only one direction, or three jets may be jetted.
You may inject more than the direction. Further, it is possible to replace the method using the cross jets in two directions with the method using the horizontal jets in one direction.

[0053]

The effects of the present invention are listed below. (A) As required, the accuracy of the radial dimension of the solidified body of the underground solidified body can be selected between high accuracy and relatively low accuracy. (B) The radial dimension of the underground solid can be increased, and the underground solid required to cover an area of a predetermined size while maintaining the accuracy and strength required for the underground solid. The number of constructions can be reduced. (C) A single jet of solidifying material enables both a cross jet and a horizontal jet. (D) The equipment and the construction period can be significantly reduced.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a first embodiment of the present invention.

FIG. 2 is a partial cross-sectional view showing an example of a solidified material ejecting unit that forms a cross jet.

FIG. 3 is a partial cross-sectional view showing another example of the solidified material ejecting means forming the cross jet.

FIG. 4 is a partial cross-sectional view showing an example of a horizontal solidifying material ejecting means.

FIG. 5 is a partial cross-sectional view showing another example of the horizontal solidifying material ejecting means.

FIG. 6 is a plan view after the construction including the underground solidified body formed by the solidifying material jetting means by the cross jet and the underground solidified body formed by the solidifying material jetting means by the horizontal jet.

7 is a vertical cross-sectional view of FIG.

FIG. 8 is a plan view after construction according to the first embodiment of the present invention.

9 is a vertical sectional view of FIG.

FIG. 10 is a plan view after construction according to the second embodiment of the present invention.

11 is a vertical cross-sectional view of FIG.

FIG. 12 is a cross-sectional view of a solidified material ejecting unit having a variable angle nozzle according to a third embodiment.

FIG. 13 is a diagram showing a case where a cross jet is formed in the partial enlarged view of FIG. 12;

FIG. 14 is a partially enlarged view of FIG. 12 showing a case of a horizontal jet flow configuration.

FIG. 15 is a cross-sectional view of a solidified material injection unit according to a fourth embodiment of the present invention, showing a case where a cross jet is formed.

FIG. 16 is a cross-sectional view of a solidified material ejecting unit according to a fourth embodiment of the present invention, showing a state in which a lower nozzle of a pair of nozzles is blocked.

FIG. 17 is a sectional view taken along line XX of FIG.

FIG. 18 is a plan view after construction according to the conventional technique.

FIG. 19 is a sectional view of a solidified material ejecting means according to a fifth embodiment of the present invention.

FIG. 20 is a sectional view showing one mode of a solidifying material flow path switching mechanism in a fifth embodiment.

21 is a cross-sectional view showing a state where FIG. 20 is switched.

[Explanation of symbols]

1 ... the first underground solid 2 ... Second underground solid 31 ... First solidifying material injection means 32 ... Second solidifying material injection means N21 ... Nozzle M11 ... Stirrer 31A ... central axis

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[Procedure amendment]

[Submission date] July 13, 2001 (2001.7.1)
3)

[Procedure Amendment 1]

[Document name to be corrected] Drawing

[Name of item to be corrected] Fig. 19

[Correction method] Change

[Correction content]

FIG. 19

Continued front page    (72) Inventor Hirohisa Yamaguchi             1-2-1 Taito, Taito-ku, Tokyo Fudoken             Inside the corporation (72) Inventor Hiroshi Yoshida             Chemika, 1-6-4 Moto-Akasaka, Minato-ku, Tokyo             Inside Le Grout Co., Ltd. F-term (reference) 2D040 AA04 AB03 BA08 BC01 BD00                       BD05 BD06 DA03 DA11 DA12                       DA16 DA17 EA18

Claims (6)

[Claims] 1. A column-shaped underground consolidating structure in which a solidifying material injection means is penetrated into the ground, a jet of the solidifying material is injected from the solidifying material injection means, and the solidifying material injection means is rotated and pulled up to the ground side. In the ground improvement method that constructs a body and constructs an underground structure with the multiple solidified submerged bodies, the solidified material is injected while forming a cross jet to control the radial dimension with high accuracy. The second submerged solidification step is performed by horizontally injecting the solidifying material in the region between the submerged solidification bodies formed in the crossing jet use step and the cross jet flow using step A ground improvement method comprising the step of using a horizontal jet to create a body. 2. A solidified material injection means is penetrated into the ground, a jet of solidified material is injected from the solidified material injection means, and the solidified material injection means is rotated and pulled up to the ground side to form a cylindrical underground consolidation. In the ground improvement method where the body is formed and the preceding underground beam and the water stop solid are constructed by the formed underground solid, the solidified material is injected while forming a cross jet and the radial dimension is increased. Having a cross jet use process for creating a pre-controlled underground beam that is accurately controlled, and a horizontal jet use process for horizontally injecting a solidifying material between the preceding underground beams to create a water blocking solid. Ground improvement method characterized by. 3. The step of exchanging the solidified material injection means for the cross jet with the solidified material injection means for the horizontal jet between the cross jet use step and the horizontal jet use step. Ground improvement method in any of 2. 4. The solidifying material jetting means comprises at least a pair of solidifying material jetting nozzles, the jetting angle of the nozzles being variable, and the jetting angle of the nozzles between the cross jet use step and the horizontal jet use step. 3. The ground improvement method according to claim 1, further comprising: performing an injection angle changing step of changing the angle so that the pair of jets are jetted in a horizontal direction from an angle at which the jets intersect. 5. The ground improvement method according to claim 4, wherein in the injection angle changing step, the solidifying material is not injected from any one of at least a pair of the solidifying material injection nozzles. 6. The solidifying material jetting means comprises at least a pair of solidifying material jetting nozzles for cross jets, and at least one solidifying material jetting nozzle for horizontal jets. The first solidifying material flow passage communicating with the solidifying material injection nozzle is opened, and the second solidifying material flow passage communicating with the solidifying material injection nozzle for horizontal jet is closed, and in the horizontal jet use step, The first solidifying material flow passage communicating with the solidifying material injection nozzle for the cross jet is closed, and the second solidifying material flow passage communicating with the solidifying material injection nozzle for the horizontal jet is opened. Ground improvement method of either one of.