JPH11256564A - Continuous two-plane soil improvement body and construction method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To dispense with special improvement works by using excavated sediment overflowing on the subsurface layers with circulation of an endless chain when a vertical soil improved body is constructed and improved sediment from a solidifying material as a part of a horizontal soil improved body for simplification. SOLUTION: Subsurface layers in a position for constructing a horizontal soil improved body 9 are excavated by an excavator, and the depth, width and sectional form of a groove 10 formed along a vertical soil improved body 8 are set according to the volume of filling improved sediment 11. While an endless chain 3 is circulated, a groove digging device 1 is moved and the width and depth of the vertical soil improved body 8 are determined according to an intended use of a combined form of a single continuous two-plane soil improved body 7. At the time of constructing the vertical soil improved body 8, improved sediment 11 of excavated sediment supplied from a cutting and stirring claw 4 with circulation of the endless chain 3 and solidifying material overflows into the groove 10. Thus, the improved sediment 11 is utilized intact as a part of the horizontal soil improved body 9, and the continuous two-plane soil improved body 7 can be completed by one process of constructing the vertical soil improved body 8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a continuous two-sided ground improvement body constructed into a T-shaped or inverted L-shaped vertical cross-section by a trench-type ground improvement machine, and a method of constructing the same.

[0002]

2. Description of the Related Art Japanese Patent Laid-Open Publication No. Hei 5-17946 discloses a digging apparatus in which an endless chain provided with a cutting stirrer is circulated around the outer circumference of a cutter post.
JP-A-5-280043, JP-A-5-280044, JP-A-9-28
Ditch-type ground improvement machines such as No. 7131, etc., by circulating the endless chain while moving in the horizontal direction while supporting the ditch device on the base machine etc. The solidified material is stirred and mixed to construct a ground improvement body that is continuous in a wall shape.

[0003] This continuous ground improvement body is mainly constructed for the purpose of supporting above-ground structures and other structures on soft ground, but especially for the purpose of strengthening soft ground and ground which may be liquefied. In this case, in order to increase the effect of constraining the ground by the ground improvement body, they are constructed in parallel or in a grid-like manner. In this case, in addition to securing trafficability, the top of the ground improvement body must be connected to another ground so that the horizontal force can be transmitted between the tops of adjacent ground improvement bodies, or to increase the bending rigidity and support force at the top. A plate-like ground improvement is connected by an improvement or connected to the top.

[0004] In this case, the minimum unit of the ground improvement body is formed from a wall-shaped vertical ground improvement body and a beam-shaped or slab-shaped horizontal ground improvement body into a T-shaped or inverted L-shaped cross section. In order to construct the ground improvement body, it is necessary to newly improve the surface ground after the construction of the vertical ground improvement body, so that the number of processes increases. In addition, at the time of the ground improvement of the surface ground, it is necessary to treat the improved soil that has overflowed into the surface ground when constructing the vertical ground improvement body. Due to the inclusion of cement, the disposal is treated as industrial waste, which requires a great deal of labor and huge costs.

[0005] Further, the horizontal ground improvement body is constructed on the surface ground, and since the trench cannot be used for its construction, it is constructed by stirring and mixing the surface ground and the solidified material with a backhoe or the like. However, since the stirring and mixing efficiency is lower than when the endless chain of the trench apparatus is used, the quality of the completed horizontal ground improvement body is relatively lower than the quality of the vertical ground improvement body.

SUMMARY OF THE INVENTION In view of the above background, the present invention proposes a continuous two-sided ground improvement body which does not require special improvement work for building a horizontal ground improvement body and does not require disposal of improved soil, and a method of building the same. It is.

[0007]

As described above, the continuous two-sided ground improvement body is constructed by a digging groove device consisting of an endless chain, which is stretched around a cutter post and the outer periphery thereof, and on which a cutting stirrer is projected. A vertical ground improvement body that is continuous in a wall shape and a horizontal ground improvement body that is connected to the top of the vertical ground improvement body and that is continuous in a slab or beam shape are formed into a T-shaped or inverted L-shaped vertical cross-sectional shape. In the present invention, when constructing a vertical ground improvement body, by using the improved soil consisting of excavated soil and solidified material that has overflowed to the surface ground with the circulation of the endless chain as it is as at least a part of the horizontal ground improvement body, Eliminates the need for extraordinary improvement work to construct a horizontal ground improvement body,
Or simplify it and eliminate the need for disposal of improved soil.

The improved soil that overflows to the surface ground due to the circulation of the endless chain corresponds to the amount of the solidified material supplied into the ground when the vertical ground improved body is constructed, and at least the volume corresponding to the supplied amount of the solidified material. The minute is used as a horizontal ground improvement body. The improved soil that overflows into the surface ground is filled in the trench formed by excavating and discharging the surface ground continuously in advance, and becomes a horizontal ground improved body as it is.

Conventionally, the improved soil which has been disposed of is used as at least a part of the horizontal ground improvement body, so that the generation of industrial waste is eliminated and the T-shaped or inverted L-shaped vertical cross-sectional shape is continuous. Since the two-sided ground improvement body is completed by one process of constructing the vertical ground improvement body, a special ground improvement work for constructing the surface horizontal ground improvement body becomes unnecessary or simplified.

[0010] In addition, the residual soil generated by the construction of the continuous two-sided ground improvement body is generated when forming a groove for filling the improvement soil overflowing to the surface ground during the construction of the vertical ground improvement body.
Disposal is easy and cost-effective because it is only ordinary soil without cement content.

[0011] In addition, the horizontal ground improvement body is composed of improved soil mixed and stirred by a trench apparatus having higher stirring and mixing efficiency than when a conventional backhoe or the like is used.
The quality of the horizontal ground improvement body and the quality of the vertical ground improvement body become uniform, and the quality of the continuous two-sided ground improvement body itself improves.

In addition, since the horizontal ground improvement body and the vertical ground improvement body are simultaneously constructed in one step, and both are integrated, the resistance to external force increases.

[0013] The basic continuous two-sided ground improvement body is described in claim 5.
As described in, after the surface ground at the horizontal ground improvement body construction position is continuously excavated and discharged to form a groove, the excavation equipment is moved along the groove while circulating the endless chain, and excavating The soil and the solidified material are stirred and mixed to construct a vertical ground improvement body, and the excavated soil overflowing to the surface ground due to the circulation of the endless chain and the improved soil made of the solidified material are filled in the trench and horizontally. It is constructed by constructing a ground improvement body.

[0014] A continuous two-sided ground improvement body in which a horizontal ground improvement body of a basic continuous two-sided ground improvement body is continuous in a slab shape is provided by connecting a continuous two-sided ground improvement body to a vertical ground. It is constituted by arranging in the thickness direction of the improved body and connecting adjacent horizontal ground improved bodies of the continuous two-sided ground improved body.

Alternatively, the continuous continuous two-sided ground improvement body is arranged with a distance between the adjacent horizontal two-sided ground improvement bodies of the continuous two-sided ground improvement body. It is constructed by filling the improved soil consisting of excavated soil and solidified material between the horizontal ground improvement bodies, or by performing the ground improvement on the surface ground between the horizontal ground improvement bodies.

According to a fourth aspect of the present invention, the vertical ground improvement body of the continuous two-sided ground improvement body according to any one of the first to third aspects is constructed in two directions, so that the vertical ground improvement body has a lattice shape. The continuous two-sided ground improvement body of the form arranged in is constructed.

The continuous two-sided ground improvement body of claim 4 is claim 6.
As described in the above, after constructing a plurality of vertical ground improvement bodies in parallel by repeating the operation of stirring and mixing the excavated soil and the solidified material by the trench equipment, in the direction intersecting the vertical ground improvement body, the horizontal ground The work of continuously excavating and discharging the surface ground at the construction position of the improved body is repeated to form a plurality of parallel grooves, and for each of the grooves, the excavated soil and solidified material are excavated along the groove A vertical ground improvement body is constructed by stirring and mixing, and a horizontal ground improvement body is constructed by filling the trench with the improved soil overflowing on the surface ground.

Alternatively, a plurality of grooves are formed in parallel by repeating the work of continuously excavating and discharging the surface ground at the construction position of the horizontal ground improvement body, and a plurality of grooves are formed for each of the grooves. Along with the trench, the excavated soil and the solidified material are agitated and mixed by a trench device to construct a vertical ground improvement body, and the improved soil overflowing in the surface ground is filled in the trench to form a horizontal ground improvement body. After constructing and constructing a plurality of continuous two-sided ground improvement bodies that are parallel to each other, the work of continuously excavating and discharging the surface layer in the direction intersecting with the continuous two-sided ground improvement body is further repeated in parallel. Grooves are formed, and for each of the grooves, the excavated soil and the solidified material are agitated and mixed by a digging device along the grooves to construct a vertical ground improvement body, and the improved soil overflowing to the surface ground is formed in the grooves. It is built by building a horizontal ground improvement body by filling in

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows how a continuous two-sided ground improvement body 7 is constructed by a trench apparatus 1. The digging groove device 1 is composed of a cutter post 2 and an endless chain 3 having a cutting stirrer 4 projecting therefrom, which is circulated around the outer periphery of the cutter post 2, and is provided with a hydraulic cylinder mounted on a base machine 5. Is moved along the frame 6 in the horizontal direction by using the base machine 5 as a reaction force, and the circulating cutting stirrer 4
While excavating the ground into a groove, the solidified material discharged from the cutter post 2 or supplied from the ground is stirred and mixed with the excavated soil to construct a ground-improved body that is continuous in a wall shape.

The continuous two-sided ground improvement body 7 is connected to the vertical ground improvement body 8 directly constructed by the trench apparatus 1 and the top of the vertical ground improvement body 8, and is connected to the slab or beam-like horizontal ground improvement body. The body 9 is constructed into a T-shaped vertical cross-sectional shape as shown in FIG. 2 or an inverted L-shaped vertical cross-sectional shape as shown in FIG. 3, and at least a part of the horizontal ground improvement body 9 is constructed when the vertical ground improvement body 8 is constructed. And the improved soil 11 made of solidified material and excavated soil that has overflowed into the surface layer due to the circulation of the endless chain 3.

Prior to the construction of the vertical ground improvement body 8 by the trench apparatus 1, as shown in FIG. 2, the surface ground at the construction position of the horizontal ground improvement body 9 is continuously excavated and discharged by an excavator such as a backhoe. A groove 10 is formed. The groove 10 is formed along the construction position of the vertical ground improvement body 8.

The depth, width, or cross-sectional shape of the groove 10 is determined in consideration of the volume of the improved soil 11 which is generated in the surface ground when the vertical ground improvement body 8 is constructed and is filled in the groove 10.
From the viewpoint of stability in the state where the
It is set to the extent that the ground on both sides in the width direction of 10 does not collapse,
The appropriate depth and width of 10 are 0.5 to 1.5 m and 1.5 to 2.5 m, respectively. The remaining soil generated by the construction of the continuous two-sided ground improvement body 7 is only the ordinary soil which is not generated when the groove 10 is formed and which is not mixed with cement.

After the formation of the groove 10, as shown in FIG. 1, the digging apparatus 1 is moved along the groove 10 while circulating the endless chain 3, and the excavated soil and the solidified material are stirred and mixed to improve the vertical ground. Build 8. The width and depth of the vertical ground improvement body 8 are determined by the use of the continuous double-sided ground improvement body 70 in which the single continuous double-sided ground improvement body 7 is combined. The solidified material may be in the form of powder or slurry.

When the vertical ground improvement body 8 is constructed, along with the circulation of the endless chain 3, from the rising side of the cutting agitating claw 4, an amount of a mixture of the excavated soil and the solidified material corresponding to the volume of the solidified material supplied from the rising side. The soil 11 overflows into the groove 10 and stays in the groove 10 as it is to be filled. The improved soil 11 is a mixture with a solidified material and has a self-hardening property, so that it naturally hardens in the groove 10 and becomes at least a part of the horizontal ground improvement body 9.

If the space in the groove 10 cannot be completely filled by the improved soil 11, the ordinary soil generated at the time of excavation of the groove 10 is backfilled depending on the degree of the gap in the groove 10, or
The solidified material is separately added to the normal soil backfilled therein, and the two are stirred and mixed, or the solidified material is added to the normal soil before being backfilled, and the solidified material is backfilled with stirring and mixing. In addition to the improved soil 11, a mixture of ordinary soil and solidified material
When the inside is filled, the horizontal ground improvement body 9 is constructed over the entire height of the groove 10.

FIG. 4 shows that a single continuous two-sided ground improvement body 7 is arranged adjacent to the vertical ground improvement body 8 in the thickness direction, and the adjacent continuous two-sided ground improvement bodies 7, 7 have a horizontal ground improvement body 9. FIG. 5 shows that a single continuous two-sided ground improvement body 7 is arranged at a distance in the thickness direction of the vertical ground improvement body 8 and spaced apart between adjacent horizontal ground improvement bodies 9 and 9 when FIG. The following shows the case where it is performed.

In the case of FIG. 4, the horizontal ground improvement bodies 9 of adjacent continuous two-sided ground improvement bodies 7 are in contact with each other.
Or it is constructed so as to overlap. In the case of FIG. 5, as shown in FIG. 6, between the horizontal ground improvement bodies 9, 9 of the adjacent continuous two-sided ground improvement bodies 7, the improved soil 11 made of excavated soil and solidified material is filled as shown in FIG. 6. Or, by performing the ground improvement on the surface ground between the horizontal ground improvement bodies 9, 9, the adjacent continuous two-sided ground improvement bodies 7, 7 are made continuous.

FIGS. 7 and 8 show a single continuous double-sided ground improvement body 7.
Are arranged on a plane so as to be orthogonal to each other in a grid pattern to form a continuous two-sided ground improvement body 70 used as a basis for various structures as described later. FIG. 7 shows continuous two-sided ground improvement bodies 7, 7 arranged in parallel in one direction with a space between horizontal ground improvement bodies 9, 9 arranged in parallel with each other. FIG. 8 shows a case where the horizontal ground improvement bodies 9 and 9 are arranged continuously, and FIG. This is the case when they are arranged.

The continuous two-sided ground improvement body 70 constituted by arranging the continuous two-sided ground improvement bodies 7 in a lattice pattern is obtained by constructing a plurality of vertical ground improvement bodies 8 arranged in one direction by the trench apparatus 1. A plurality of grooves 10 are formed in parallel with each other in a direction perpendicular to the grooves. For each of the grooves 10, a vertical ground improvement body 8 is constructed along the grooves 10 by the digging apparatus 1 and overflows into the grooves 10. By constructing the horizontal ground improvement body 9 by directly filling the improved soil 11 or after forming a plurality of grooves 10 arranged in one direction, a plurality of parallel continuous two-sided ground improvement bodies 7 are constructed, It is constituted by constructing a plurality of continuous two-sided ground improvement bodies 7 arranged in parallel in a direction orthogonal to the continuous two-sided ground improvement body 7. 7 and 8 show a case where the continuous two-sided ground improvement body 70 is formed by the latter method.

FIG. 9 shows a case where the grid-like continuous two-sided ground improvement body 70 shown in FIG. 7 or FIG. 8 is used as a foundation for supporting an embankment structure, a retaining wall, an abutment, etc., and FIG. Shows the case when used as a basis for In any case, the single continuous two-sided ground improvement body 7 is arranged in a lattice shape,
Liquefaction prevention effect can be expected if implemented on sandy ground. FIG. 11 shows a case where a continuous two-sided ground improvement body 70 is used as a measure for preventing liquefaction of an existing dike or other soil structure.

[0031]

According to the present invention, at the time of constructing a vertical ground improvement body, the improved soil consisting of excavated soil and solidified material that has overflowed to the surface ground due to the circulation of the endless chain is used as it is as at least a part of the horizontal ground improvement body. A single step of constructing a vertical ground improvement body can complete a continuous two-sided ground improvement body with a T-shaped or inverted L-shaped vertical cross-sectional shape. Can be unnecessary or simplified.

In addition, the use of the improved soil, which has been conventionally discarded, as at least a part of the horizontal ground improvement body eliminates the generation of industrial waste, and the residual soil generated by the construction of the continuous two-sided ground improvement body. Is easy to use and does not require any cost, because it is only ordinary soil without cement content, which is generated when forming a groove for filling the improved soil.

Further, since the horizontal ground improvement body is composed of the improved soil stirred and mixed by the trench apparatus having higher stirring and mixing efficiency than the conventional case using a backhoe or the like, the quality of the horizontal ground improvement body and the vertical The quality of the ground improvement body becomes uniform, and the quality of the continuous two-sided ground improvement body itself improves.

Further, since the horizontal ground improvement body and the vertical ground improvement body are simultaneously constructed in one step, and both are integrated, the resistance to external force is large.

Since a continuous two-sided ground improvement body having a T-shaped or inverted L-shaped cross section can be constructed in one step, a continuous two-sided ground improvement body arranged in a lattice can be completed in a small number of steps, that is, in a short time. Therefore, when adopted as a basis for various structures, there are no obstacles in the construction period, the range of use is widened, and when it is applied to sandy ground, it is also a liquefaction prevention measure.

[Brief description of the drawings]

FIG. 1 is an elevational view showing how a vertical ground improvement body is constructed by a trench apparatus.

FIG. 2 is a perspective view showing a construction procedure of a continuous two-sided ground improvement body having a T-shaped cross section.

FIG. 3 is a perspective view showing a continuous two-sided ground improvement body having an inverted L-shaped cross section.

FIG. 4 is a perspective view showing a state where adjacent continuous two-sided ground improvement bodies are arranged in contact with each other.

FIG. 5 is a perspective view showing a state where adjacent continuous two-sided ground improvement bodies are arranged at intervals.

FIG. 6 is a cross-sectional view showing a state where continuous horizontal ground improvement bodies of a continuous two-sided ground improvement body at intervals are connected.

FIG. 7 is a perspective view showing a state in which continuous two-sided ground improvement bodies are arranged in a grid.

FIG. 8 is a perspective view showing a state in which continuous two-sided ground improvement bodies are arranged in a grid pattern.

FIG. 9 is a cross-sectional view showing a case where a grid-like continuous two-sided ground improvement body is used as a foundation for an embankment structure or the like.

FIG. 10 is a cross-sectional view showing a case where a grid-like continuous two-sided ground improvement body is used as a foundation of a building structure.

FIG. 11 is a cross-sectional view showing a case where a grid-shaped continuous two-sided ground improvement body is used as a foundation of an earth structure.

[Explanation of symbols]

1 ... Drilling groove device, 2 ... Cutter post, 3 ... Endless chain, 4 ... Cutting stirrer claw, 5 ... Base machine, 6 ...
... frame, 7, 70 ... continuous two-sided ground improvement, 8 ... vertical ground improvement, 9 ... horizontal ground improvement, 10 ... groove, 11 ...
… Improved soil.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Shigeru Yoshida 6-13-7 Akasaka, Minato-ku, Tokyo Tenox Co., Ltd.

Claims (7)

[Claims] 1. A ground improvement constructed by agitating and mixing excavated soil and solidified material using a digging groove device consisting of an endless chain having a cutter post and a cutting agitating claw projecting from the periphery of the cutter post. The vertical ground improvement body that is continuous to the wall shape and the horizontal ground improvement body that is connected to the top of the vertical ground improvement body and that is continuous in the form of a slab or a beam forms a T-shaped or inverted L-shaped vertical cross-sectional shape. A continuous two-sided ground improvement body in which at least a part of the horizontal ground improvement body is an improved soil composed of excavated soil and solidified material that has overflowed to the surface ground due to endless chain circulation when the vertical ground improvement body is constructed. 2. The continuous two-sided ground improvement body according to claim 1,
A continuous two-sided ground improvement body configured by arranging in the thickness direction of a vertical ground improvement body a state in which adjacent horizontal two-sided ground improvement bodies are continuous. 3. The continuous two-sided ground improvement body according to claim 1,
Arrange in the thickness direction of the vertical ground improvement body with a distance between each horizontal ground improvement body of the adjacent continuous two-sided ground improvement body, and between the horizontal ground improvement bodies of the adjacent continuous two-sided ground improvement body. Continuous two-sided ground improvement in which the improved soil consisting of excavated soil and solidified material is filled or the surface ground between horizontal ground improvement bodies is subjected to ground improvement and adjacent horizontal ground improvement bodies are continuously formed body. 4. The continuous two-sided ground improvement body according to claim 1, wherein the vertical ground improvement body is constructed in two directions. 5. A method for constructing a continuous two-sided ground improvement body according to claim 1, wherein a digging groove device comprising an endless chain provided with a cutter agitator and a cutting stirrer protruding from a cutter post and an outer periphery thereof is used. Yes, after continuously excavating and discharging the surface ground at the construction site of the horizontal ground improvement body, forming a groove, and moving the excavation device along the groove while circulating the endless chain, excavated soil and solidified material Agitated and mixed to construct a vertical ground improvement body, and filled the trench with improved soil consisting of excavated soil and solidified material that overflowed into the surface layer due to the circulation of the endless chain to form a horizontal ground improvement body. Construction method of continuous two-sided ground improvement body to be constructed. 6. A method for constructing a continuous two-sided ground improvement body according to claim 4, using a digging groove device comprising an endless chain provided with a cutter agitator and a cutting stirrer protruding from a cutter post and an outer periphery thereof. Yes, by moving the trench apparatus while circulating the endless chain, repeating the work of stirring and mixing the excavated soil and solidified material to construct multiple parallel vertical ground improvement bodies, and then intersect with the vertical ground improvement body In the direction, the operation of continuously excavating and discharging the surface ground at the construction position of the horizontal ground improvement body is repeated to form a plurality of parallel grooves, and for each groove, the endless chain is circulated along the groove The excavated soil and solidified material are moved and the excavated soil is stirred and mixed together to construct a vertical ground improvement body, and the improved soil consisting of excavated soil and solidified material that has overflowed to the surface ground due to endless chain circulation. To fill the groove A method for constructing a continuous two-sided ground improvement body for building a ground improvement body. 7. A method for constructing a continuous two-sided ground improvement body according to claim 4, wherein a digging groove device comprising an endless chain provided with a cutter agitator and a cutting stirrer protruding from a cutter post and an outer periphery thereof is used. Yes, the work to continuously excavate and unload the surface ground at the construction position of the horizontal ground improvement body is repeatedly formed to form a plurality of parallel grooves, and for each of the grooves, while circulating the endless chain along the grooves Move the digging equipment, stir and mix the excavated soil and solidified material to construct a vertical ground improvement body,
An improved soil consisting of excavated soil and solidified material overflowing into the surface ground due to the circulation of the endless chain is filled in the trench to construct a horizontal ground improvement body, and a plurality of parallel continuous two-sided ground improvement bodies are constructed. After that, a plurality of grooves are formed in parallel by repeating the work of continuously excavating and discharging the surface layer ground in a direction intersecting the continuous two-sided ground improvement body, and for each of the grooves, along the grooves The trench is moved while circulating the endless chain, and the excavated soil and the solidified material are stirred and mixed to construct a vertical ground improvement body, and the excavated soil that has overflowed into the surface layer due to the circulation of the endless chain is solidified. A method for constructing a continuous two-sided ground improvement body in which an improved soil made of a material is filled in the groove to construct a horizontal ground improvement body.