JP2008038468A - Jetting and stirring method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a jetting and stirring method capable of minimizing wasteful construction and securing the necessary thickness dimension of an effective cross section. <P>SOLUTION: A solidifying material is jetted and stirred in ranges L1 with considerably large areas by a first jetting and stirring means 40 (jetting method for large areas). The solidifying material is jetted and stirred, by a second jetting and stirring means 10, in the range LB surrounded by the ranges L1 with considerably large areas and common tangents (T1, T2) of the ranges with considerably large areas (jetting method for large areas). The jetting and stirring of the solidifying material in the latter range (LB) is desirably performed after the jetting and stirring of the solidifying material in the former ranges (L1). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention is a construction method used for ground improvement, liquefaction prevention construction method, etc., and injecting a solidifying material into an area where an underground solidified body is to be created or an area where liquefaction is to be prevented. The present invention relates to a jet stirring method for stirring the soil in the region.

  As such a jet stirring method, for example, a cutting fluid is jetted from the nozzle at the tip of the stirring blade provided in the spray device, and the jets jetted from the top and bottom of the stirring blade are collided at a predetermined position radially outward. A method of forming a jet, injecting solidified material from the inlet below the stirring shaft, and pulling up while rotating the stirring shaft to cut the in-situ soil and mixing and stirring the solidified material is known ( Patent Document 1).

In order to shorten the construction period and reduce construction costs, such a jet stirring method is often performed in a plurality of adjacent regions (two locations in FIGS. 19 to 21). In FIG. 19, FIG. 20, the area | region L1P which performed the jet stirring construction method is constructed at two places.
And two area | regions L1P and L1P which performed the jet stirring construction method are providing the area | region Ls to be applied in duplication, and an effective cross section or its thickness dimension is determined from an intensity | strength viewpoint. In FIG. 19, the thickness dimension of the effective cross section is indicated by reference numeral D1, and in FIG. 20, the thickness dimension of the effective cross section is indicated by reference numeral D2.

When the overlapping area Ls is smaller, it is not necessary to perform unnecessary construction, and the consumption of the solidified material and other costs can be reduced. However, as is apparent from FIGS. 19 and 20, when the overlapping area Ls is small, the thickness dimension of the effective cross section becomes small.
Specifically, the overlapping area Ls is smaller in the conventional technique shown in FIG. 19 than in the conventional technique shown in FIG. 20, and is better from the viewpoint of cost saving. However, the thickness D1 of the effective cross section in FIG. 19 is clearly smaller than the thickness D2 of the effective cross section in FIG.
That is, if it is going to enlarge the thickness dimension (D1, D2) of an effective cross section, the area | region Ls constructed redundantly must be enlarged, and there exists a problem that it is not preferable from a viewpoint of cost reduction.

For such a problem, for example, as shown in FIG. 21, the region Ls overlapped in the two regions L1P and L1P subjected to the jet stirring method is reduced, and the region Ls overlapped is reduced. It is conceivable to separately perform a jet stirring method for a relatively small area in both side portions.
In FIG. 21, when a region of a comparatively small area where the jet stirring method is applied is indicated by a symbol L3P, the region L3P is applied as compared with the thickness D3 of the effective cross section when the region L3P is not applied. The effective cross-sectional thickness dimension D4 increases significantly.

However, in the region L3P, the hatched portion does not contribute to the increase in the effective cross section at all. Therefore, the hatched portion is useless for the purpose of increasing the effective cross section.
Furthermore, since there is a portion where the region L3P and the region L1P overlap, useless construction increases.
JP 2001-115446 A

  The present invention has been proposed in view of the above-described problems of the prior art, can reduce unnecessary construction to the minimum necessary, and can secure the necessary effective cross-sectional thickness dimension. The purpose is to provide a spray mixing method that can be used.

  In the jet stirring method of the present invention, the solidified material is jetted and stirred by the first jet stirring means (monitor 40) in a region having a relatively large area (regions where the large area spray method is applied: L1, L1A). The area (L1) having a relatively large area and the common tangent line (T1, area L1 having a relatively large area) by the first step (large area injection method) and the second injection stirring means (monitor 10) And a second step (small area injection method) of injecting and stirring the solidified material in the region surrounded by (T2) (contained region: LB) (Claim 1). .

  Here, in both the first step (large area injection method) and the second step (small area injection method) described above, the first and second injection agitating means (monitor 40, monitor 10) are predetermined. It is preferable that the material penetrates to a depth of 1 mm, then is pulled up to the ground side, and the solidified material is jetted and stirred at the stage of lifting.

  In the present invention, the second jet agitating means (monitor 10) is disposed below the first jet agitating means (monitor 40) by a predetermined distance (δ), and the predetermined distance from the first step. It is preferable that the second step is performed after a time corresponding to (δ) has elapsed.

  Here, in the present invention, in the second step, a region having a relatively large area (from nozzles N, N1 to N5) provided from the plurality of solidified material injection means (nozzles N, N1 to N5) provided in the second injection agitation means (monitor 10). L1) and a plurality of solidified material jets (Js) are jetted into a region (constricted region: LB) surrounded by the common tangents (T1, T2) (of the region L1 having a relatively large area). (Claim 3).

  Alternatively, the second jet agitating means (monitor 10) is configured to be rotatable or swingable. In the second step, the area (L1) having a relatively large area and the area L1 (with a relatively large area). It is preferable to inject a solidified material jet (Js) to a region surrounded by the common tangent lines (T1, T2) (contained region: LB).

  According to the jet agitation method of the present invention having the above-described configuration, the regions (L1, L1) where the large area injection method is applied can be set so that there is almost no overlapping portion, and is wasteful. Can be eliminated as much as possible. And the in-situ soil remaining in the area (LB) between the areas (L1, L1) where the large area injection method has been constructed is solidified in the second step (injection method with a small construction area). Is injected and mixed with the solidified material and stirred, so that the necessary effective cross-sectional thickness dimension (D) is ensured.

  Here, the thickness dimension (D) of the effective cross section is equal to or less than the interval of the common tangent lines (T1, T2), and the solidification material is injected in the second step (the injection method with a small construction area). The solidified material jet (Js) is limited to a region (contained region LB) surrounded by a relatively large region (L1) and common tangents (T1, T2) (of the region L1 having a relatively large area). Injecting the solidified material onto the region irrelevant to the effective cross section (hatched portion in the region L3P in FIG. 21) can save the waste of construction.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
In the drawing, similar members are denoted by the same reference numerals.
FIG. 1 shows a construction procedure of a jet stirring method according to the first embodiment of the present invention.
First, an injection method having a large construction area (a large area injection method), for example, a method combining mechanical stirring and stirring using a so-called “cross jet” (described later in FIGS. 13 to 18) Construction is performed on a plurality of adjacent areas indicated by L1 (two adjacent areas in the illustrated embodiment) (see FIG. 1).

As shown in FIG. 1, in the illustrated embodiment, the areas L1 and L1 where the large area injection method is applied are set so that there is almost no overlapping portion, and unnecessary construction is eliminated as much as possible. Yes.
As a result, in the region indicated by the symbol LB in FIG. 1, that is, the “boiled region” between the regions L1 and L1 where the large-area injection method is applied, the original soil remains without being applied.
In FIG. 1, the areas L1 and L1 in which the large area injection method is applied are represented as being in point contact, but in actual construction, there are some overlapping portions as shown in FIG. Install in the same way. This is to prevent the formation of a so-called “nest” where the in-situ soil remains without being constructed.

In the drowned areas LB and LB, the ground improvement is performed by shortening the reach of the solidified material jet such as cement milk and mortar injected from the monitor 10, for example, a small area injection method (for example, small area injection method) In addition, a boring hole (not clearly shown in FIG. 1) for excavating a spraying method for preventing liquefaction is excavated. A solidifying material injection device (monitor) 10 is inserted into a boring hole not shown in FIG.
Then, as shown in FIG. 1, the solidified material jet Js was jetted from the monitor 10 and drowned in the areas LB and LB between the areas L1 and L1 where the large area injection method was applied. The soil and solidifying material in the regions LB and LB are mixed.

As shown in FIG. 1, the jet Js of the solidified material is injected into the drowned areas LB and LB, and the soil and the solidified material in the drowned areas LB and LB are mixed, so that the stirring injection method is applied. The thickness D of the effective cross section in the region is ensured to be equal to or greater than the thickness D2 of the effective cross section shown in FIG.
Moreover, unlike the prior art shown in FIG. 20, there are almost no overlapping areas of the areas L1 and L1 where the large area injection method is applied, and unnecessary construction is omitted to the limit.

The drowned region LB will be described with reference to FIG.
In FIG. 2, two tangent lines (virtual lines) in contact with both the areas L1 and L1 where the large area injection method is applied, that is, common tangent lines T1 and T2 are indicated by two-dot chain lines. A center line CL connecting the centers of the areas L1 and L1 where the large area injection method is applied is indicated by a one-dot chain line.
The regions LB and LB between which the large area injection method L1 and L1 are constructed are regions on the center line CL side with respect to the common tangents T1 and T2, and hatching is given in FIG. It is expressed.
In other words, in FIG. 2, the regions LB and LB are regions surrounded by the common tangents T1 and T2 and the regions L1 and L1 where the large-area injection method is applied.

In FIG. 1 again, the monitor 10 is arranged in the drowned region LB, and the solidifying material jet Js is injected from the monitor 10 only in the drowned region LB.
As is clear from FIG. 1 and FIG. 2, the thickness dimension D (FIG. 1) of the effective cross section in the region where the jet agitation method according to the embodiment is applied is less than the dimension between the common tangents T1 and T2. In addition, the region where the solidifying material jet Js is injected from the monitor 10 is limited to the inner side (arrow I1 and I2 side in FIG. 2) than the common tangents T1 and T2. Therefore, according to the illustrated embodiment, the solidifying material jet Js is not injected from the monitor 10 in a region other than the effective cross section (a region outside the range indicated by the dimension D in FIG. 1).
Therefore, as shown in FIG. 21, a region irrelevant to the effective section (a hatched portion in the region L3P in FIG. 21) is not constructed.

1 to 9, the monitor 10 is configured to inject a plurality of solidified material jets Js without rotating.
On the other hand, the monitor 10 can be configured to be rotatable or swingable, and a single solidified material jet Js can be ejected while rotating or swinging the streamline. Details will be described later with reference to FIGS. 11 and 12.

Here, in the step of injecting the solidified material jet Js from the monitor 10 to the drown regions LB and LB (small area injection method: FIG. 1), the large area injection method is applied to the regions L1 and L1. Done after being done. Details will be described later with reference to FIGS.
However, depending on the construction conditions, the large area injection method for the regions L1 and L1 and the small area injection method for the drown regions LB and LB can be performed simultaneously.

A small area injection method for the drown regions LB and LB will be described with reference to FIGS.
FIG. 3 shows the process shown in FIG. 1 in a simplified manner.
In FIG. 3, the solidified material jet Js is jetted from the monitor 10 to the areas LB and LB where the large area injection method L1 and L1 are drawn. In order to simplify the illustration, in FIG. 3, the solidified material jets Js are each ejected from the monitor 10 by five.

In order to describe a mode in which the in-situ soil of the swollen region LB is cut by the solidified material jet Js ejected from the monitor 10, in FIG. 3, a region F4 surrounded by a dotted line (including the swollen region LB) ), And only the region F4 is shown in FIGS.
In FIG. 4, the in-situ soil of the drowned region LB is shown with hatching. For simplification, only three solidifying material jets Js ejected from the monitor 10 are shown, and symbols Js1 to Js3 are given. The central solidifying material jet Js2 is injected toward the overlapping portion of the areas L1 and L1 where the large area injection method is applied, and the solidifying material jets Js1 and Js3 are injected to the left and right of the solidifying material jet Js2. .
As shown in FIG. 4, the in-situ soil of the drowned region LB is cut by the solidifying material jets Js1 to Js3. In other words, at the stage shown in FIG. 4, the in-situ soil in a straight line connecting the monitor 10 (not shown in FIG. 4) and the areas L1 and L1 where the large-area injection method is applied is formed by the solidified material jets Js1 to Js3. Cutting and stirring.

  In FIG. 5, the left and right solidifying material jets Js1 and Js3 collide with the areas L1 and L1 where the large area injection method is applied, and then two jets (arrows Js1-1, Js1-2, and Js3-1). , Js3-2). Then, due to the solidifying material jets Js1 to Js3 and the energy of the divided flow, the regions indicated by reference symbols α1 and α2 in FIG. 6 are shredded and mixed well with the solidifying material without becoming a lump, The “nest” of the original soil is prevented from being created.

Although not shown, regions other than the regions α1 and α2 in the drowned region LB are also solidified material jets Js and their shunts (arrows Js1-1, Js1-2, Js3-1, Js3 in FIGS. 5 and 6). 2)), the in-situ soil is cut and agitated and mixed well with the solidified material.
FIG. 7 shows a state after the in-situ soil in the drowned region LB has been cut and stirred.

3 to 7, the solidifying material jet Js splits along the boundary between the regions L <b> 1 and L <b> 1 as shown in FIGS. 5 to 7 after colliding with the regions L <b> 1 and L <b> 1 where a large area injection method is applied. It is injected to do.
In other words, the injection direction is set so that the solidified material jet Js is not injected in a direction that does not collide with the region L1 like the jet Jsw-1 shown in FIG. Alternatively, the injection direction of the solidifying material jet Js is set so that it does not turn away from the drowned region LB after colliding with the region L1, like the jet Jsw-2 shown in FIG. Has been.

In FIGS. 1-8, the area | regions L1 and L1 which constructed the large-area injection method are set so that the overlapping part may become small. On the other hand, as shown in FIG. 9, when the adjacent regions L1 and L1 are constructed so that the overlapping portions of the regions L1 and L1 subjected to the large area injection method are enlarged, the flaws between the regions L1 and L1 The portion LBA thus made becomes extremely small, and the effective thickness is not so different from the region L1.
In such a case, it is not necessarily necessary to execute the small area injection method described with reference to FIGS.

For the region L1, even when the effective thickness is large, the region indicated by the symbol L1A in FIG. 9, that is, the “gourd” shaped region composed of the two regions L1 and L1 constructed so that the overlapping portion becomes large is adjacent. When the region where the gourd-shaped regions L1A and L1A overlap with each other is small, the effective thickness becomes small due to the existence of the narrowed region LB between them.
In such a case, the small area injection method described with reference to FIGS. 3 to 7 is executed in the drooped region LB between the gourd-shaped regions L1A and L1A.

FIG. 10 schematically shows a mechanism for injecting five solidified material jets Js as shown in FIGS.
In FIG. 10, the monitor 10 is provided with a solidified material flow path L <b> 10 supplied from the facility on the ground side and injection nozzles N <b> 1 to N <b> 5 for injecting the solidified material. In FIG. 10, for simplification of illustration, the injection nozzles N1 to N5 are expressed as simple through holes.
With such a configuration, the monitor 10 does not rotate but injects a plurality (five in FIG. 10) of solidified material jets Js.

3 to 9, the monitor 10 does not rotate, and jets a plurality of solidified jets Js. However, the monitor 10 may be configured to be rotatable or swingable by known and existing techniques. I can do it.
In such a case, even if only one jet Js of the solidifying material is jetted and the monitor 10 itself is rotated or swung, the in-situ soil in the drown region LB can be cut and collapsed. Is possible.
11 and 12 show such a case.

First, in FIG. 11, a monitor that swings is indicated by reference numeral 10A.
The monitor 10A is connected to a device on the ground side via a rod (not shown). Such a ground-side device conventionally swings the monitor 10A continuously or intermittently clockwise or counterclockwise as indicated by an arrow R11 using a known technique.
Although the monitor 10A of FIG. 11 includes only a single nozzle N, the solidified material jet Js moves, for example, between a position indicated by a solid line and a position indicated by a dotted line when the monitor 10A swings. 3 to 9, the entire drowned region LB is cut with the solidifying material jet Js and chopped, and the in-situ soil of the drowned region LB does not become a lump and is well mixed with the solidifying material. The

A monitor 10B shown in FIG. 12 has a configuration substantially similar to that of the monitor 10A shown in FIG. 11, but is rotated in the position direction as indicated by an arrow R12 by a ground-side device (not shown). In FIG. 12, the monitor 10B rotates clockwise, but may be rotated counterclockwise (opposite the arrow R12).
The monitor 10B is set with a cover 12 having a semicircular arc shape.
Although not clearly shown in FIG. 12, when the drown region LB exists in the lower part in FIG. 12, the cover 12 is attached so as to cover the upper half of the monitor 10B.

In FIG. 12, if the nozzle N is directed downward (in the side of the drowned region LB) while the monitor 10B is rotating, the solidified material jet Js is injected into the drowned region LB (FIG. 12). Solid line arrows).
On the other hand, when the nozzle N is not directed to the swollen region LB but is directed to the cover 12, the solidified material jet Js (dotted arrow in FIG. 12) injected from the nozzle N is It is interrupted by.
By comprising in this way, the solidification material jet Js is injected only into the drowned area | region LB (lower area | region of FIG. 12: not shown in FIG. 12).

FIGS. 13 and 14 show an apparatus for applying the jet stirring method according to the first embodiment of FIGS.
FIG. 13 shows the overall configuration, and FIG. 14 schematically shows a portion that acts on the soil in the ground.

In FIG. 13, the construction machine on the ground side generally indicated by reference numeral 20 has a vehicle part 22 for moving and operating the construction machine 20 and a standing part 24 for standing a member to a predetermined depth. ing.
For example, two rods 26 and 28 are provided in the standing portion 24. The rod 26 is provided with equipment for constructing a large area injection method at the lower end thereof. The lower end portion of the rod 28 is provided with a device for performing a small area injection method.
The sign δ at the lower ends of the rod 26 and the rod 28 will be described with reference to FIG.

In FIG. 13, the upper ends of the rod 26 and the rod 28 are connected to the drive and reduction device 30. Although not shown, the drive and reduction device 30 is provided with a motor (transmission motor or hydraulic motor) as a drive source, a reduction gear, and a swivel joint, and the motor is controlled by an inverter.
If it is possible to prevent the monitor 10 (10A, 10B) provided on the rod 28 from rotating by the drive and reduction device 30 (monitor 10: FIG. 10), the monitor 10 (10A: 10A: 11) and can be rotated (monitor 10B, FIG. 12).
Note that the drive and reduction device 30 is configured to be able to move the standing portion 24 in the vertical direction of FIG.

In FIG. 14, two rods 26 each having a device for applying a large area injection method and two rods 28 each having a device for applying a small area injection method are provided.
In FIG. 14, only one rod 28 is shown, but the other rod 28 is located on the far side in the direction perpendicular to the paper surface and is hidden by the rod 28 on the near side.
The rod 26 and the rod 28 are connected by connecting rods 34 and 34.

At the lower end of the rod 26, a device for applying a large area injection method, that is, a monitor 40 is provided.
The monitor 40 has stirring blades 42 and 44 extending in the horizontal direction (left and right in FIG. 14), and a nozzle for solidifying material injection (not shown) provided at the ends of the stirring blades 42 and 44. is doing.
Since the stirring blades 42 and 44 are provided at intervals in the vertical direction (vertical direction in FIG. 14), the nozzles (not shown) provided at the end portions are also spaced at regular intervals in the vertical direction. And, as shown in FIG. 14, the solidified material jets Jc for the large area injection method injected from the nozzles are solidified material jets Jc injected from the nozzles provided at intervals in the vertical direction. At C, they collide to form a so-called “cross jet”.

As a result of the solidified material jets Jc colliding with each other at the intersection C, the excavation of the in-situ soil by the solidified material jets Jc is limited to the region between the rod 26 and the intersection C (region inward in the radial direction).
Then, if the rod 26 is rotated by the drive and speed reducer 30 (FIG. 13), the in-situ soil can be directly agitated by the rotating blades 42 and 44, and agitation is performed while cutting the in-situ soil by the solidifying material jet Jc. It can be done.

Below the rod 28, the above-described monitor 10 (10A, 10B) is attached.
Here, the position of the nozzle N of the monitor 10 in the vertical direction (vertical direction in FIG. 14) is positioned below the intersection C where the intersecting jets Jc and Jc from the monitor 40 collide with each other by the distance indicated by the symbol δ. ing.
This is because the small area injection method (construction in the engraved region LB in FIGS. 3 to 9) performed by the monitor 10 is performed on the large area injection method (in the region L1 in FIGS. 1 to 9) performed by the monitor 40. This is because it will be carried out after the construction).

As described with reference to FIGS. 3 to 9, the construction of cutting and stirring the in-situ soil in the region LB drowned by the monitor 10 is premised on the existence of the region L <b> 1 where the large-area injection method is applied. . Therefore, it is necessary to delay the construction by the monitor 10 by a predetermined time from the construction by the monitor 40.
Here, both the construction for injecting the binder jet Jc from the monitor 40 and the construction for injecting the binder jet Js from the monitor 10 are performed by pulling up the monitor after reaching the deepest part of the construction area. Is called.
If the monitor 10 is positioned below the monitor 40, the monitor 10 is lifted after the monitor 40 is lifted for the same vertical position. That is, after the large area injection method is applied to the region L1 by the monitor 10, the construction (small area injection method) shown in FIGS. 3 to 9 is performed in the region LB where the monitor 40 is drowned. .

Here, the solidified material injected from the monitor 10 and the solidified material injected from the monitor 40 are the same.
In FIG. 13, the solidified material flows through the flow paths L14-1 and L14-2 in the rod 26 from a solidified material supply device (not shown) on the ground side.
The flow path L14-1 in the right rod 26 branches into a flow path L14-1S in the connecting rod 34 and a flow path L14-1L in the right rod 26. The solidified material flowing through the flow path L14-1L flows through the flow paths L42 and L44 in the stirring blades 42 and 44 of the monitor 40, and is ejected as a cross jet Jc. Then, the solidified material flowing through the flow path L14-1S flows through the flow path L28 in the rod 28 and is ejected from the monitor 10.
The flow path L14-2 in the left rod 26 also branches into the flow path L14-2S in the connecting rod 34 and the flow path L14-1L in the left rod 26, and the solidified material that flows through the flow path L14-1L. Is injected from the monitor 40, and the solidified material flowing through the flow path L14-1S is injected from the monitor 10.

  In FIG. 14, it appears that the flow path L <b> 14-1 </ b> S and the flow path L <b> 14-2 </ b> S merge and flow through the flow path L <b> 28 in the rod 28. However, as described above, there are two rods 28 in FIG. 14 in the direction perpendicular to the paper surface, and each of the flow paths L14-1S and L14-2S has either of the two rods 28. Flowing.

In FIG. 14, the solidified material flowing in the rod 28 is supplied via the flow paths L14-1, L14-2 in the rod 26 and the flow paths L14-1S, L14-2S in the connecting rod 34. Yes. Instead of this, it is desirable to omit the flow paths L14-1S and L14-2S in the connecting rod 34 and separately form a solidifying material supply flow path in the rod 28.
This is to cope with the case where the solidification material injection from the monitor 10 is continued after the solidification material injection from the monitor 40 is stopped. That is, in such a case, it is preferable that the solidification material supply path of the monitor 10 and the solidification material supply path of the monitor 40 are independent from each other. A flow path needs to be formed.

15 to 18 show a second embodiment of the present invention.
The injection agitation method according to the first embodiment as shown in FIG. 1 can be implemented by applying a small area injection method to two drown regions LB using two monitors 10.
Here, for example, if a jet stirring method is applied to a continuous region in the longitudinal direction, such as an underground wall, and an effective thickness is ensured, a large area jet method and a small area jet method are used. It is not sufficient to perform the small area injection method with the monitor 10 only in the two drown regions LB. This is because a region LB that is drowned between the regions L1 and L1 where the large area injection method has been applied and that is not subjected to the small area injection method on the monitor 10 is formed.
Therefore, in the case where the jet stirring method is applied to the continuous region in the longitudinal direction and the effective thickness is ensured, as shown in FIG. 15 and FIG. It is necessary to apply the injection method to four drowned regions LB.

FIG. 15 shows the soil side where the jet stirring method is applied, and FIG. 16 shows the arrangement of the rods 26 and 28 in the construction machine 20.
1 to 8, the small area injection method is applied using the monitor 10 only in the region LB between the regions L1 and L1 where the large area injection method is applied. On the other hand, in 2nd Embodiment, as shown in FIG. 15, the area | region where a jet stirring construction method is constructed about continuous areas like a continuous wall (to the left-right direction of FIG. 15), and a solidification material is injected In order to secure the effective thickness of the thinned area LB-1, LB-1, not only the narrowed areas LB-1, LB-1, but also the narrowed areas LB-2, LB-2 on the left side of the small area using the monitor 10 A spraying method is used to mix in-situ soil and solidified material.

As shown in FIG. 15, in order to construct a small area injection method for the drown regions LB-1, LB-1, LB-2, LB-2, as shown in FIG. 10 is required to be provided on the construction machine 20 (only the connecting rod 34 and the rods 26 and 28 are shown in FIG. 16).
If the construction machine 20 shown in FIG. 16 is used to construct the jet agitation method, all drowned regions LB (LB-1, LB-2) that exist between the regions L1, L1 where the large area jet method is constructed. ), A small area injection method using the monitor 10 provided at the lower end of the rod 26 is applied.
Therefore, it is possible to simultaneously satisfy the demand for reducing the useless construction by reducing the area where the areas L1 and L1 overlap and the demand for increasing the effective thickness D as much as possible.

FIG. 17 and FIG. 18 show the parts of a construction machine that constructs the second embodiment. The construction machine 20 is the same as that shown in FIGS. 13 and 14 except that four rods 26 each having the monitor 10 at the lower end are provided.
And the other structure and effect in 2nd Embodiment are the same as that of 1st Embodiment.

The illustrated embodiment is merely an example, and is not intended to limit the technical scope of the present invention.
For example, in the illustrated embodiment, a large-area injection method is performed in two regions L1 and L1 in one construction, but it may be performed in only one location, or may be performed simultaneously in three or more locations. It is.
Moreover, although the small area injection method is constructed after the large area injection method is constructed, it is also possible to construct both simultaneously.

The top view for demonstrating construction of 1st Embodiment of this invention. The top view for demonstrating the drowned area | region. The top view for demonstrating the construction in the drowned area. The elements on larger scale of FIG. The elements on larger scale explaining the step following FIG. 4 in the drowned area. FIG. 6 is a partially enlarged view illustrating a stage following FIG. 5. The elements on larger scale explaining the step following FIG. The elements on larger scale which show the injection state of the improper solidification material in the drowned area | region. The top view for demonstrating the modification of 1st Embodiment. Sectional drawing which shows typically the apparatus used by construction of the drowned area. Sectional drawing which shows the modification of the apparatus of FIG. Sectional drawing which shows another modification of the apparatus of FIG. 1 is an overall view of an apparatus for implementing a first embodiment. FIG. 14 is a partial front view showing members performing work in the ground in the apparatus of FIG. 13. The top view for demonstrating construction of 2nd Embodiment of this invention. The top view which shows arrangement | positioning of the rod in the apparatus which constructs 2nd Embodiment. The front view of the principal part of the apparatus which constructs 2nd Embodiment. The top view of the principal part of the apparatus shown in FIG. The top view explaining a prior art. The top view explaining the state which constructed the prior art different from FIG. The top view explaining the prior art different from FIG. 19, FIG.

Explanation of symbols

L1 ... Area L1P where a large construction area is applied (Large area injection construction method) L1P, L3P ... Area where a jet agitation method according to the prior art is applied L1C ... Drilling hole LB ... Large area 10, 10 A, 10 B, 40... Monitor Js, Js-1 to Js-5... Solidified material jet Jc... Solidified material constituting crossing jet Jet L1A ... Gourd-shaped region 20 in which injection stirring method is applied ... Construction machine 22 ... Vehicle part 24 ... Standing part 26, 28 ... Rod 30 ... Drive and speed reducer 34 ... Connecting rod C ... Intersection N ... Nozzle L10, L14-1, L14-2, L14-1L, L14-1S, L14-2L, L14-2S, L42 ... Solidified material flow path

Claims (4)

  A first step of injecting and stirring the solidified material in a region having a relatively large area by the first jet agitating means, and a region having a relatively large area and a common tangent line by the second jet agitating means. And a second step of injecting and agitating the solidified material into the region.   The second jet agitating unit is disposed below the first jet agitating unit by a predetermined distance, and the second step is performed after a time corresponding to the predetermined distance has elapsed from the first step. The jet stirring method according to claim 1.   In the second step, a plurality of solidified materials from a plurality of solidified material injection means provided in the second injection agitating means to a region surrounded by a relatively large area and a common tangent thereof. The jet stirring method according to claim 1, wherein a jet is jetted.   The second jet agitating means is configured to be rotatable or swingable, and in the second step, the solidifying material jet is jetted into a region surrounded by a relatively large area and a common tangent line. The jet stirring method according to any one of claims 1 and 2.

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