JPH07189241A - Ground improving machine and method of ground improving construction - Google Patents
Ground improving machine and method of ground improving constructionInfo
- Publication number
- JPH07189241A JPH07189241A JP5334548A JP33454893A JPH07189241A JP H07189241 A JPH07189241 A JP H07189241A JP 5334548 A JP5334548 A JP 5334548A JP 33454893 A JP33454893 A JP 33454893A JP H07189241 A JPH07189241 A JP H07189241A
- Authority
- JP
- Japan
- Prior art keywords
- shaft
- excavation
- ground
- ground improvement
- excavating
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Landscapes
- Consolidation Of Soil By Introduction Of Solidifying Substances Into Soil (AREA)
- Investigation Of Foundation Soil And Reinforcement Of Foundation Soil By Compacting Or Drainage (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本願発明は、建築物の基礎部分が
設置される位置にある地盤の土壌とスラリー溶液（固化
材）とを混合させて地盤を柱状に改良するための地盤改
良機及びその地盤改良機を使用して行う地盤改良工法に
関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ground improvement machine for improving the shape of a ground into a column by mixing soil of the ground at a position where a foundation portion of a building is installed with a slurry solution (solidifying material). The present invention relates to a ground improvement method using the ground improving machine.
【０００２】[0002]
【従来の技術】この種の地盤改良工事においては、地盤
改良機により、地盤を柱状に掘削するとともにその掘削
した土壌中に地盤改良用のスラリー溶液を混合・撹拌し
て地盤改良を行うようにしている。ところで、従来の地
盤改良機を使用して行う地盤改良工法では、回転装置で
掘削軸を掘削方向に回転させて、その先端にある掘削翼
により地盤を掘進しながらその掘削した土壌とスラリー
溶液とを混合・撹拌させ、掘削翼を所定深さまで掘進さ
せた後に、掘削軸を逆回転させながら上方に引抜くよう
にして行われている。尚、掘削軸の引抜き作業は、回転
装置で掘削軸を反掘削方向（引抜き方向）に回転させな
がら、回転装置つき掘削軸をウインチ装置で引き上げる
ようにして行われる。2. Description of the Related Art In this type of ground improvement work, a ground improvement machine is used to excavate the ground in a columnar shape and mix and stir a slurry solution for ground improvement into the excavated soil to perform the ground improvement. ing. By the way, in the soil improvement method using the conventional soil improvement machine, the excavating shaft is rotated in the excavating direction by the rotating device, and the excavated soil and the slurry solution are excavated while excavating the soil by the excavation blades at the tip thereof. Is mixed and stirred, the excavation blade is advanced to a predetermined depth, and then the excavation shaft is reversely rotated to be pulled upward. The excavation work of the excavation shaft is performed by rotating the excavation shaft in the anti-excavation direction (extraction direction) with the rotating device and pulling up the excavation shaft with the rotating device with the winch device.
【０００３】[0003]
【発明が解決しようとする課題】ところが、従来から行
われている地盤改良工法では、掘削軸の引抜き時に、掘
削軸を引抜き方向に回転させながら、単にウインチ装置
で引き上げるようにして行うため、削孔内の土壌の密度
が低くなり、地盤改良された削孔内は土壌が低密度の状
態で固化されるようになる。従って、従来の地盤改良工
法では、地盤改良された固化柱の強度が低くなるという
問題があった。尚、従来の地盤改良工法において、地盤
改良すべき固化柱の強度を大きくするには、該固化柱の
直径を大きくしたり、深さを深くしたり、あるいはスラ
リー溶液（固化材）の量を多くしたりする等の手段が考
えられるが、いずれの場合もコストが高くなるという問
題がある。However, in the conventional ground improvement method, when the excavation shaft is pulled out, the excavation shaft is simply pulled up by the winch device while rotating in the extraction direction. The density of the soil in the holes becomes low, and the soil becomes solidified in a low density state in the ground-improved hole. Therefore, the conventional ground improvement method has a problem that the strength of the ground-improved solidified column becomes low. In the conventional ground improvement method, in order to increase the strength of the solidified column to be improved, the diameter of the solidified column is increased, the depth is increased, or the amount of the slurry solution (solidified material) is increased. It is conceivable to increase the number, but in any case, there is a problem that the cost becomes high.
【０００４】本願発明は、上記した従来の問題点に鑑
み、地盤改良工事によって形成される固化柱を、その直
径や深さを大きくすることなくしかも固化材を多くする
ことなしに高強度に形成し得るようにした地盤改良機及
び地盤改良工法を提案することを目的とするものであ
る。In view of the above conventional problems, the present invention forms a solidified column formed by ground improvement work with high strength without increasing its diameter or depth and without increasing the amount of solidifying material. It is an object of the present invention to propose a ground improvement machine and a ground improvement method that are made possible.
【０００５】[0005]
【課題を解決するための手段】本願請求項１の発明は、
回転軸の下端部に掘削翼を設けた掘削軸を回転装置によ
って回転させながら地盤中を掘進させ、しかも回転軸を
通して削孔内に吐出されるスラリー溶液と土壌とを混合
・撹拌するようにした地盤改良機において、回転装置の
上部に、掘削軸に対して上下に振動を与える振動発生装
置を連結したことを特徴としている。The invention according to claim 1 of the present application is as follows.
The excavation shaft provided with excavation blades at the lower end of the rotary shaft is advanced by excavating the ground while rotating the rotary device, and the slurry solution discharged into the drilling hole through the rotary shaft and the soil are mixed and stirred. The ground improvement machine is characterized in that a vibration generator for vertically vibrating the excavation shaft is connected to the upper part of the rotating device.
【０００６】回転軸下端部の掘削翼は、平面視において
適宜の面積を有する板状のものが採用され、且つ掘進方
向の先行側が下方となるような傾斜状態で設置されてい
る。又、振動発生装置は、その作動時に掘削軸を回転装
置とともに上下に振動せしめ得るものである。As the excavation blade at the lower end of the rotary shaft, a plate-shaped blade having an appropriate area in plan view is adopted, and is installed in an inclined state such that the leading side in the excavation direction is downward. Further, the vibration generating device is capable of vibrating the excavation shaft together with the rotating device up and down during its operation.
【０００７】本願請求項２の発明は、請求項１の地盤改
良機を使用して行う地盤改良工法であって、掘削軸で削
孔を所定深さまで形成した後、掘削軸が削孔内にある状
態で、振動発生装置を作動させて掘削軸に上下方向の振
動を与えながら且つ該掘削軸を回転装置で反掘削方向に
回転させながら、掘削軸を順次上方に引抜くようにして
行うことを特徴としている。The invention according to claim 2 of the present application is a ground improvement method which is carried out by using the ground improvement machine according to claim 1, wherein the drilling shaft is formed in a predetermined depth after the drilling shaft is formed to a predetermined depth. In a certain state, while operating the vibration generator to give vertical vibration to the excavation shaft and rotating the excavation shaft in the anti-excavation direction by the rotating device, the excavation shaft is sequentially withdrawn upward. Is characterized by.
【０００８】[0008]
【作用】本願発明の地盤改良機を使用して行われる地盤
改良工法では、地盤を改良すべき位置において、通常の
方法により、回転装置で掘削軸を掘進方向に回転させな
がら掘削翼で地盤を所定深さまで掘進する。このとき、
回転軸を通してスラリー溶液（固化材）を土壌中に混合
・撹拌させる。そして、地盤中を所定深さまで掘進した
後、掘削軸を削孔から引抜く際に、振動発生装置を作動
させて掘削軸に上下方向の振動を与えながら且つ回転装
置で掘削軸を反掘削方向（引抜き方向）に回転させなが
ら掘削軸を順次上方に引抜くようにする。このように、
掘削軸の引抜き時に、振動発生装置で掘削軸に振動を与
えながら且つ回転装置で掘削軸を引抜き方向に回転させ
ながら行うと、掘削翼の下面でその下方に位置する土壌
（スラリー溶液が混合されている）を順次転圧して締め
固めながら掘削軸を引抜くことができる。従って、削孔
内の土壌を高密度に締め固めた状態で固化させることが
できるようになる。In the ground improvement method performed by using the ground improving machine of the present invention, the ground is improved by the conventional method at the position where the ground should be improved while rotating the excavation shaft in the excavation direction by the rotating device. Dig to a specified depth. At this time,
The slurry solution (solidifying material) is mixed and stirred in the soil through the rotating shaft. Then, after excavating the ground to a predetermined depth, when pulling out the excavation shaft from the drilled hole, the vibration generator is operated to apply vertical vibration to the excavation shaft and the excavation shaft is rotated in the anti-excavation direction with the rotating device. The excavation shaft is sequentially withdrawn upward while rotating in the (withdrawal direction). in this way,
When the excavation shaft is pulled out, the vibration is applied to the excavation shaft by the vibration generator, and the excavation shaft is rotated in the extraction direction by the rotating device. It is possible to pull out the excavation shaft while compacting by sequentially rolling. Therefore, it becomes possible to solidify the soil in the drilled hole in a highly compacted state.
【０００９】[0009]
【発明の効果】このように、本願発明の地盤改良機及び
地盤改良工法では、掘削軸の引抜き作業時に、振動発生
装置で掘削軸に上下方向の振動を与えながら行うことに
より、削孔内の土壌を高密度に締め固めることができ、
形成すべき固化柱の直径及び深度を大きくすることなく
しかも固化材の量を多くすることなしに、高強度の地盤
改良を行うことができるという効果がある。As described above, according to the ground improvement machine and the ground improvement method of the present invention, during the extraction work of the excavation shaft, the vibration is applied to the excavation shaft in the vertical direction by the vibration generator so that You can compact the soil with high density,
There is an effect that high-strength ground improvement can be performed without increasing the diameter and depth of the solidified column to be formed and without increasing the amount of solidifying material.
【００１０】[0010]
【実施例】以下、図１及び図２を参照して本願発明の実
施例を説明すると、図示実施例の地盤改良機は、掘削軸
１を回転装置５で回転させながら地盤を掘進して削孔Ｐ
を形成するとともに、その削孔Ｐ内の土壌中にスラリー
溶液（固化材）を吐出させて地盤改良を行うようにした
ものである。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. In the ground improvement machine of the illustrated embodiment, the excavation shaft 1 is rotated by a rotating device 5 to excavate and excavate the ground. Hole P
Is formed and a slurry solution (solidifying material) is discharged into the soil in the hole P to improve the ground.
【００１１】この地盤改良機は、自走式の台車（クロー
ラ）１０に支持部材１２，１３でガイド支柱１１を支持
するとともに、台車１０のウインチ装置１４から繰り出
したワイヤー１５で、ガイド支柱１１の上端部から振動
発生装置６つきの掘削装置Ａを吊下げて構成している。In this ground improvement machine, a guide prop 11 is supported by a supporting member 12 and 13 on a self-propelled carriage (crawler) 10, and a wire 15 fed from a winch device 14 of the carriage 10 is used to guide the guide strut 11. The excavator A with the vibration generator 6 is suspended from the upper end.
【００１２】掘削装置Ａは、回転軸２の下端部に掘削翼
３を設け、さらに該回転軸２の所定高さ位置に上下に間
隔をもって複数の撹拌翼４，４，４を設けた掘削軸１を
回転装置（オーガーモータ）５によって正・逆両方向に
回転せしめ得るように構成されている。尚、掘削翼３及
び各撹拌翼４は、それぞれ回転軸２の対向位置に一対設
けられている。The excavator A has an excavation blade 3 provided at the lower end of the rotary shaft 2 and a plurality of stirring blades 4, 4, 4 vertically spaced apart at a predetermined height position of the rotary shaft 2. 1 is rotated by a rotating device (auger motor) 5 in both forward and reverse directions. A pair of the excavating blade 3 and the stirring blades 4 are provided at opposite positions of the rotary shaft 2.
【００１３】掘削翼３は、平面視において適宜の面積を
有する板状のものを採用している。又、該掘削翼３は、
掘進方向の先行側が下方となるような傾斜状態で回転軸
２の下端部に設置されている。The excavation blade 3 is a plate-shaped blade having an appropriate area in plan view. Further, the excavation blade 3 is
It is installed at the lower end of the rotating shaft 2 in an inclined state such that the leading side in the excavation direction is downward.
【００１４】回転軸２の内部には中空穴（図示省略）が
形成されており、該中空穴を通して回転軸２の下端部に
設けた吐出口からセメントミルクのようなスラリー溶液
を吐出させることができるようになっている。A hollow hole (not shown) is formed inside the rotary shaft 2, and a slurry solution such as cement milk can be discharged through a discharge port provided at the lower end of the rotary shaft 2 through the hollow hole. You can do it.
【００１５】振動発生装置６は、油圧モータを駆動させ
ることにより偏心輪を回転させて上下に振動を発生せし
め得るようにした、いわゆるバイブロ装置が採用されて
いる。そして、この振動発生装置６は、回転装置５の上
部に連結し、さらにウインチ装置１４から繰り出された
ワイヤー１５の先端部を振動発生装置６の上部に連結し
ている。そして、この振動発生装置６つきの掘削装置Ａ
は、ワイヤー１５でガイド支柱１１の上端部から吊下げ
た状態で、ウインチ１４の操作により上下動せしめ得る
ようになっている。The vibration generating device 6 employs a so-called vibro device in which an eccentric wheel can be rotated by driving a hydraulic motor to generate vertical vibration. The vibration generator 6 is connected to the upper part of the rotating device 5, and the tip of the wire 15 fed from the winch device 14 is further connected to the upper part of the vibration generator 6. Then, the excavator A with the vibration generator 6 is attached.
Can be moved up and down by operating the winch 14 while being suspended from the upper end of the guide column 11 by the wire 15.
【００１６】この地盤改良機を使用して行う地盤改良工
法について説明すると、図１に示すように、台車１０を
移動させて掘削軸１を地盤改良すべき予定場所に鉛直姿
勢で位置させる。そして、回転装置５を作動させ、ウイ
ンチ装置１４を緩めることにより、掘削軸１を順次地盤
中に掘進させていく。このとき、回転軸２の下端部から
スラリー溶液（固化材）を吐出させることにより、掘削
翼３で掘削された土壌とスラリー溶液とを混合させ、さ
らに各撹拌翼４，４，４により土壌とスラリー溶液とを
均一に撹拌する。Explaining the ground improvement method using this ground improvement machine, as shown in FIG. 1, the bogie 10 is moved to position the excavation shaft 1 in a vertical posture at a planned site for ground improvement. Then, the rotating device 5 is operated and the winch device 14 is loosened, so that the excavation shaft 1 is sequentially excavated into the ground. At this time, the slurry solution (solidified material) is discharged from the lower end of the rotary shaft 2 to mix the soil excavated by the excavation blade 3 with the slurry solution, and further the soil is excavated by the respective stirring blades 4, 4, 4. Stir uniformly with the slurry solution.
【００１７】そして、掘削翼３を所定の深さまで掘進さ
せて所望深さの削孔Ｐを形成した後、一旦回転装置５を
停止させ、続いて該回転装置５により掘削軸１を逆回転
させながら、且つ振動発生装置６を作動させて掘削軸１
に上下方向の振動を与えながらウインチ装置１４により
掘削装置Ａを順次引き上げていく。すると、掘削翼３が
回転されながら振動発生装置６により上下に振動せしめ
られることにより、該掘削翼３の下面で削孔Ｐ内の土壌
（スラリー溶液が混合している）Ｑを転圧して締め固め
るように作用する。このように、土壌Ｑが締め固められ
ると、該土壌Ｑの密度が高くなり、削孔Ｐ内で形成され
る固化柱の強度を大きくできる。つまり、形成すべき固
化柱の直径又は深さを大きくすることなく、しかもスラ
リー溶液（固化材）の量を多くすることなしに高強度の
地盤改良を行うことができる。After excavating the excavation blade 3 to a predetermined depth to form a hole P having a desired depth, the rotating device 5 is once stopped, and then the excavating shaft 1 is reversely rotated by the rotating device 5. While operating the vibration generator 6,
The excavator A is sequentially pulled up by the winch device 14 while applying vertical vibration to the. Then, as the excavation blade 3 is rotated, it is vertically vibrated by the vibration generator 6, so that the soil (mixed with the slurry solution) Q in the drilled hole P is compacted and tightened on the lower surface of the excavation blade 3. Acts to harden. In this way, when the soil Q is compacted, the density of the soil Q becomes high and the strength of the solidified columns formed in the drilled holes P can be increased. That is, high-strength ground improvement can be performed without increasing the diameter or depth of the solidified columns to be formed and without increasing the amount of the slurry solution (solidifying material).
【図１】本願発明の実施例にかかる地盤改良機の側面図
である。FIG. 1 is a side view of a ground improvement machine according to an embodiment of the present invention.
【図２】図１の地盤改良機の使用状態説明図である。FIG. 2 is an explanatory view of a usage state of the ground improvement machine of FIG.
１は掘削軸、２は回転軸、３は掘削翼、４は撹拌翼、５
は回転装置、６は振動発生装置、Ａは掘削装置、Ｐは削
孔、Ｑは土壌である。1 is an excavation axis, 2 is a rotation axis, 3 is an excavation blade, 4 is a stirring blade, 5
Is a rotating device, 6 is a vibration generator, A is an excavator, P is a drilling hole, and Q is soil.
Claims (2)
設けた掘削軸（１）を回転装置（５）によって回転させ
ながら地盤中を掘進させ、しかも回転軸（２）を通して
削孔（Ｐ）内に吐出されるスラリー溶液と土壌とを混合
・撹拌するようにした地盤改良機であって、 前記回転装置（５）の上部に、前記掘削軸（１）に対し
て上下に振動を与える振動発生装置（６）を連結した、 ことを特徴とする地盤改良機。1. An excavation shaft (1) having an excavation blade (3) at the lower end of a rotation shaft (2) is rotated by a rotating device (5) to advance into the ground, and through the rotation shaft (2). A ground improvement machine configured to mix and agitate a slurry solution discharged into a boring hole (P) and soil, which is provided above and below the excavation shaft (1) above the rotating device (5). A ground improvement machine, characterized in that a vibration generating device (6) for giving vibration to is connected.
（１）で削孔（Ｐ）を所定深さまで形成した後、掘削軸
（１）が削孔（Ｐ）内にある状態で、振動発生装置
（６）を作動させて前記掘削軸（１）に上下方向の振動
を与えながら且つ該掘削軸（１）を回転装置（５）で反
掘削方向に回転させながら、該掘削軸（１）を順次上方
に引抜くようにして行うことを特徴とする地盤改良工
法。2. A state in which the excavation shaft (1) is in the drilling hole (P) after the drilling shaft (1) is used to form the drilling hole (P) to a predetermined depth by using the ground improvement machine of claim 1. While operating the vibration generator (6) to vertically vibrate the excavation shaft (1) and rotate the excavation shaft (1) in the anti-excavation direction by the rotating device (5), A ground improvement method characterized in that the shaft (1) is sequentially pulled upward.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5334548A JPH07189241A (en) | 1993-12-28 | 1993-12-28 | Ground improving machine and method of ground improving construction |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5334548A JPH07189241A (en) | 1993-12-28 | 1993-12-28 | Ground improving machine and method of ground improving construction |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH07189241A true JPH07189241A (en) | 1995-07-28 |
Family
ID=18278651
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP5334548A Pending JPH07189241A (en) | 1993-12-28 | 1993-12-28 | Ground improving machine and method of ground improving construction |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH07189241A (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH1161802A (en) * | 1997-08-22 | 1999-03-05 | Y B M:Kk | Agitator of foundation improvement machine |
| JP2002105948A (en) * | 2000-10-02 | 2002-04-10 | Sekisui House Ltd | Soil improvement method making use of ultrasonic wave and agitation machine for soil improvement |
| JP2011140762A (en) * | 2010-01-05 | 2011-07-21 | Ohbayashi Corp | Drilling and agitating equipment, and soil improvement method |
| JP2011140760A (en) * | 2010-01-05 | 2011-07-21 | Ohbayashi Corp | Drilling and agitating equipment |
| JP2011157767A (en) * | 2010-02-02 | 2011-08-18 | Ohbayashi Corp | Drilling and stirring device and method of improving ground |
| JP2017133257A (en) * | 2016-01-28 | 2017-08-03 | 株式会社大林組 | Boring agitation apparatus |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS50152506A (en) * | 1974-05-28 | 1975-12-08 | ||
| JPH0387413A (en) * | 1989-08-30 | 1991-04-12 | Sumitomo Cement Co Ltd | Construction method for columnar consolidation body in ground improvement and its device |
-
1993
- 1993-12-28 JP JP5334548A patent/JPH07189241A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS50152506A (en) * | 1974-05-28 | 1975-12-08 | ||
| JPH0387413A (en) * | 1989-08-30 | 1991-04-12 | Sumitomo Cement Co Ltd | Construction method for columnar consolidation body in ground improvement and its device |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH1161802A (en) * | 1997-08-22 | 1999-03-05 | Y B M:Kk | Agitator of foundation improvement machine |
| JP2002105948A (en) * | 2000-10-02 | 2002-04-10 | Sekisui House Ltd | Soil improvement method making use of ultrasonic wave and agitation machine for soil improvement |
| JP2011140762A (en) * | 2010-01-05 | 2011-07-21 | Ohbayashi Corp | Drilling and agitating equipment, and soil improvement method |
| JP2011140760A (en) * | 2010-01-05 | 2011-07-21 | Ohbayashi Corp | Drilling and agitating equipment |
| JP2011157767A (en) * | 2010-02-02 | 2011-08-18 | Ohbayashi Corp | Drilling and stirring device and method of improving ground |
| JP2017133257A (en) * | 2016-01-28 | 2017-08-03 | 株式会社大林組 | Boring agitation apparatus |
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