JPH0776509B2 - Stabilization method of tunnel face - Google Patents
Stabilization method of tunnel faceInfo
- Publication number
- JPH0776509B2 JPH0776509B2 JP7404089A JP7404089A JPH0776509B2 JP H0776509 B2 JPH0776509 B2 JP H0776509B2 JP 7404089 A JP7404089 A JP 7404089A JP 7404089 A JP7404089 A JP 7404089A JP H0776509 B2 JPH0776509 B2 JP H0776509B2
- Authority
- JP
- Japan
- Prior art keywords
- chemical solution
- face
- pipe
- injection
- drilling
- 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.)
- Expired - Fee Related
Links
Landscapes
- Consolidation Of Soil By Introduction Of Solidifying Substances Into Soil (AREA)
- Excavating Of Shafts Or Tunnels (AREA)
Description
【発明の詳細な説明】 （産業上の利用分野） 本発明は隧道工事やシールド工事において、砂質土を主
とした切羽の掘削作業に際し、切羽の崩壊や天端の崩落
を防止するための、トンネル切羽の安定工法に係るもの
である。DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention is intended to prevent collapse of a cutting face and collapse of a crown at the time of excavating a face mainly made of sandy soil in a tunnel or a shield work. This is related to the stable construction method of tunnel face.
（従来の技術） 従来この種のトンネル切羽の安定工法として、トンネル
孔（ａ）内より放射状に外周地山内に掘削機（ｂ）によ
って掘削方向に対して斜め方向に削孔し、（第11図及び
第14図参照）次いで前記掘削機（ｂ）による切羽削孔部
（ｃ）に鋼管パイプ（ｄ）を挿入し、（第12図及び第15
図参照）前記鋼管パイプ（ｄ）に設けた注入口より地盤
改良薬液注入装置（ｅ）を介して切羽掘削部外周に地盤
改良薬液（ｆ）を注入するパイプルーフ工法が適用され
ている。（第13図及び第16図並に第17図参照） なお、第18図及び第19図は他の従来工法として薬液注入
工法による切羽の状態を示すものである。(Prior Art) Conventionally, as a stable construction method of this kind of tunnel face, a hole is radially drilled from the inside of the tunnel hole (a) into the outer ground by an excavator (b) in a direction oblique to the excavation direction (11th Then, insert a steel pipe (d) into the face drilling hole (c) by the excavator (b) (see FIGS. 12 and 15).
(Refer to the drawing) A pipe roof construction method is applied in which the soil improvement chemical solution (f) is injected from the injection port provided in the steel pipe (d) to the outer periphery of the face excavation portion through the soil improvement chemical solution injection device (e). (See FIG. 13 and FIG. 16 as well as FIG. 17) Note that FIG. 18 and FIG. 19 show the state of the cutting face by the chemical liquid injection method as another conventional method.
図中（ｇ）は切羽、（ｈ）はトンネル孔（ａ）のモルタ
ル吹付層である。In the figure, (g) is the face and (h) is the mortar sprayed layer of the tunnel hole (a).
（発明が解決しようとする課題） 前記従来のパイプルーフ工法は、切羽に指向して鋼管パ
イプが斜方向に打込まれるので、同鋼管パイプの先端に
至るに伴ってパイプ間隔が大きくなるため、鋼管パイプ
の打設間隔が重要な要素であり、先端薬液注入範囲を考
慮して注入間隔を決めるため、手前側では無駄な薬液を
注入することとなり、不経済であり、且つ余分な手間を
要した。(Problems to be solved by the invention) In the conventional pipe roof construction method, since the steel pipe is driven in an oblique direction toward the face, the pipe interval increases as the tip of the steel pipe increases. Since the interval for placing steel pipes is an important factor, and the injection interval is determined in consideration of the tip chemical injection range, wasteful chemicals are injected on the front side, which is uneconomical and requires extra labor. did.
また前記従来の薬液注入工法においては、薬液の過不足
が生じ確実性に不安があった。Further, in the above-mentioned conventional chemical liquid injection construction method, there is an excess or deficiency of the chemical liquid and there is concern about the certainty.
本発明は前記従来工法の有する問題点に鑑みて提案され
たもので、その目的とする処は、従来工法より薬液注入
量が少なく、しかもより効果的に切羽の崩壊や天端の崩
落を防止するトンネル切羽の安定工法を提供する点にあ
る。The present invention has been proposed in view of the problems of the conventional method, and the purpose thereof is to reduce the injection amount of the chemical liquid as compared with the conventional method, and more effectively prevent the collapse of the face and the collapse of the crown. The point is to provide a stable construction method for the tunnel face.
（課題を解決するための手段） 前記の目的を達成するため、本発明に係るトンネル切羽
の安定工法によれば、隧道工事やシールド工事における
砂質土を主として切羽の掘削作業において、掘削孔の外
周に沿って放射状に、掘削方向に対して斜め方向に削孔
するとともに、同各削孔部に、中心軸線に対して互いに
所要の角度を以って交差する複数方向に薬液注入口が配
設された地盤改良薬液注入パイプを挿入し、前記掘削部
の外周地盤に中心軸より複数の分岐部が放射状に岐出さ
れた断面形の薬液注入層を造成するものである。(Means for Solving the Problem) In order to achieve the above object, according to the tunnel face stabilization method of the present invention, sand excavation work is mainly performed on sandy soil in tunnel construction or shield work, Along the outer circumference, holes are drilled diagonally with respect to the excavation direction, and at each of the drilled parts, chemical solution inlets are arranged in multiple directions that intersect each other at the required angle with respect to the central axis. The ground improvement chemical solution injection pipe provided is inserted, and a chemical solution injection layer having a cross-sectional shape in which a plurality of branch portions are radially extended from the central axis is formed in the outer peripheral ground of the excavation portion.
（作用） 本発明によれば前記したように、トンネル切羽の掘削孔
の外周に沿って放射状に掘削方向と斜め方向に掘削した
削孔部に挿入された地盤改良薬液注入パイプより切羽
に、同パイプの中心軸線に対して互いに所定の角度を以
って交差する複数方向に配設された噴射ノズルを介して
地盤改良薬液を噴射注入することによって、同地山内に
従来の円形断面より力学的に有利な中心軸線より分岐部
が放射状に岐出された断面形の地盤改良薬液層が順続し
て形成され、切羽が効果的に補強され、トンネル切羽の
安定化が図られる。(Operation) According to the present invention, as described above, the ground improving chemical solution injection pipe inserted into the drilled portion radially drilled along the outer periphery of the drill hole of the tunnel face is inserted into the drilled portion, By injecting the soil-improving chemicals through the injection nozzles arranged in a plurality of directions that intersect each other at a predetermined angle with respect to the central axis of the pipe, the ground improvement chemical solution can be mechanically injected into the ground with a conventional circular cross section. The ground improvement chemical liquid layer having a cross-sectional shape in which the bifurcation is radially diverged from the advantageous central axis is successively formed, the face is effectively reinforced, and the tunnel face is stabilized.
（実施例） 以下本発明を図示の実施例について説明する。(Examples) The present invention will be described below with reference to illustrated examples.
トンネル穴（１）内より地盤に応じてウオータージエツ
ト，ボーリングマシン，オーガー等の削孔機械（２）に
よって切羽（３）内を削孔する。（第１図参照）図中
（４）はモルタル吹付層である。The inside of the face (3) is drilled from the tunnel hole (1) by a drilling machine (2) such as water jet, boring machine, auger, etc. according to the ground. (See FIG. 1) In the figure, (4) is a mortar spraying layer.
かくしてトンネル穴（１）外周部に放射状に設けられた
削孔部（５）に、地盤改良薬液注入装置（６）の薬液注
入パイプ（6a）を挿入する。（第２図参照）通常は削孔
後、前記掘削機械（２）のロツド（2a）をそのまま薬液
注入パイプに転用する。図中（７）はパツキン等からな
る薬液漏洩防止装置である。Thus, the chemical solution injection pipe (6a) of the ground improvement chemical solution injection device (6) is inserted into the hole drilling portion (5) radially provided on the outer peripheral portion of the tunnel hole (1). (See FIG. 2) Usually, after drilling, the rod (2a) of the excavating machine (2) is diverted as it is to the chemical injection pipe. In the figure, (7) is a chemical liquid leakage prevention device including a packing or the like.
前記薬液注入パイプ（6a）には、第８図及び第９図に示
すように、同パイプ（6a）の中心軸線に対して互いにほ
ぼ直交する３方向に薬液注入口（８）が配設されてい
る。As shown in FIGS. 8 and 9, the chemical injection pipe (6a) is provided with chemical injection ports (8) in three directions substantially orthogonal to the central axis of the pipe (6a). ing.
なお施工前に、前記注入パイプ（6a）の引抜き速度、薬
液注入圧薬液注入量を決定するためのテストを実施す
る。Before the construction, a test is performed to determine the withdrawal speed of the injection pipe (6a) and the chemical solution injection pressure.
かくしてテストが終了すると薬液注入パイプ（6a）の間
隔及び角度を決定し、同注入パイプ（6a）を所定の速度
で引抜きながら所定量の地盤改良薬液を所定注入圧で切
羽に注入して地盤改良薬液層（９）を造成する。When the test is completed in this way, the interval and angle of the chemical solution injection pipe (6a) are determined, and a predetermined amount of ground improvement chemical solution is injected into the face with a predetermined injection pressure while pulling out the injection pipe (6a) at a predetermined speed to improve the ground. Create a chemical layer (9).
かくして地盤改良薬液の注入作業が完了すると更にトン
ネル穴（１）の掘進を続け、前記した工程を反覆して切
羽の安定化を図る。（第３図参照） 図中（10）は次回掘削予定線である。Thus, when the injection work of the ground improvement chemical solution is completed, the tunnel hole (1) is further continued to be dug, and the above steps are repeated to stabilize the face. (See Fig. 3) (10) in the figure is the next planned excavation line.
而して前記薬液注入パイプ（6a）は前記したように、そ
の中心軸線に対して互いにほぼ直交する３方向に薬液注
入口（８）が設けられているので、同各注入口（８）か
ら地中に噴射された薬液は先拡がりのＴ字型断面の薬液
注入層（９）を形成する。（第４図乃至第７図参照） このように前記実施例によれば切羽に造成された地盤改
良薬液層が従来工法の円形断面に比して力学的に有利な
Ｔ字型断面部を同心円周上に沿って連設した断面に構成
されるので薬液の注入量が少なくて済む。As described above, since the chemical liquid injection pipe (6a) is provided with the chemical liquid injection ports (8) in three directions substantially orthogonal to each other with respect to the central axis thereof, the chemical liquid injection pipe (6a) The chemical solution injected into the ground forms a chemical solution injection layer (9) having a T-shaped cross section with a divergent shape. (See FIGS. 4 to 7) As described above, according to the embodiment, the ground improving chemical liquid layer formed on the face is concentric with the T-shaped cross section which is mechanically advantageous as compared with the circular cross section of the conventional method. Since the cross-sections are continuously arranged along the circumference, the injection amount of the chemical solution can be small.
なお前記薬液注入パイプ（6a）に設けられる薬液注入口
（８）を、同パイプの軸線に対して所定の角度を以って
交差するように任意数、放射状に配設することによっ
て、Ｔ字型断面の他に 状等の断面形の薬液注入層（９）を形成するようにして
もよい。In addition, by arranging an arbitrary number of chemical liquid injection ports (8) provided in the chemical liquid injection pipe (6a) at a predetermined angle with respect to the axis of the pipe, a T-shape can be obtained. Besides mold section You may make it form the chemical | medical solution injection layer (9) of cross-sectional shape, such as a shape.
第10図は前記地盤改良薬液注入作業の自動制御装置を示
し、（11）はコンプレツサー（12）と地盤改良薬液注入
パイプ（6a）との間に介装された薬液注入圧制御装置、
（13）は前記薬液注入パイプ（6a）の引抜速度制御装
置、（14）は薬液タンク（15）と地盤改良薬液注入装置
（６）とを接続する薬液供給管路に介装された薬液注入
量制御装置で、前記各制御装置（11）（13）（14）はコ
ンバーター（16）に接続され、同コンバーター（16）は
マイクロコンピューター（17）に接続されている。図中
（18）は同マイクロコンピューター（17）に接続された
デイスプレーである。FIG. 10 shows an automatic control device for the soil improvement chemical liquid injection work, (11) is a chemical liquid injection pressure control device interposed between the compressor (12) and the soil improvement chemical liquid injection pipe (6a),
(13) is a withdrawal speed control device for the chemical injection pipe (6a), (14) is a chemical injection inserted in a chemical supply line connecting the chemical tank (15) and the ground improvement chemical injection device (6) In the quantity control device, each of the control devices (11) (13) (14) is connected to a converter (16), and the converter (16) is connected to a microcomputer (17). In the figure, (18) is a display connected to the microcomputer (17).
なお図中点線部分は薬液注入系を、実線は自動制御系を
示すものである。The dotted line in the figure shows the chemical injection system, and the solid line shows the automatic control system.
而して前記薬液注入量制御装置によって、地盤改良薬液
の切羽内へ注入圧、注入量及び前記薬液注入パイプ（6
a）の引抜速度を自動調整して、切羽内にＴ字型断面の
薬液注入層を造成するものである。Thus, by the chemical liquid injection amount control device, the injection pressure, the injection amount and the chemical liquid injection pipe (6
By automatically adjusting the withdrawal speed in a), a chemical solution injection layer having a T-shaped cross section is formed in the face.
なお 状等の断面形の薬液注入層を造成する場合も、前記と同
様にして薬液注入作業の自動制御を行なうものである。Note that Even when a chemical solution injection layer having a cross-sectional shape such as a shape is formed, the chemical solution injection work is automatically controlled in the same manner as described above.
（発明の効果） 本発明によれば前記したように、隧道工事やシールド工
事における砂質土を主とした切羽の掘削作業において、
掘削孔の外周に沿って放射状に掘削方向に対して斜め方
向に削孔し、同各削孔部に、中心軸線に対して互いに所
定の角度を以って交差する複数方向に薬液注入口が配設
された地盤改良薬液注入パイプを挿入して削孔部外周切
羽に地盤改良薬液を注入し、同削孔部全周を覆う中心軸
より複数の分岐部が放射状に岐出された断面形の地盤改
良薬液層を造成することによって、砂質土切羽の崩壊や
天端の崩落が防止される。(Effects of the Invention) According to the present invention, as described above, in the excavation work of a face mainly on sandy soil in a tunnel construction or a shield construction,
Radially drilled along the outer periphery of the drill hole diagonally with respect to the drilling direction, and at each drilled portion, chemical liquid injection ports are provided in a plurality of directions intersecting with the central axis at a predetermined angle with each other. A cross-sectional shape in which a ground improvement chemical solution injection pipe is inserted and the ground improvement chemical solution is injected into the outer peripheral face of the drilled hole, and multiple branch parts are radially diverged from the central axis that covers the entire circumference of the drilled hole. By creating the soil improvement chemical liquid layer, the collapse of the sandy soil face and the collapse of the crown can be prevented.
また中心軸より複数の分岐部が放射状に岐出された断面
形の薬液注入層は前記従来工法において造成される円形
断面の薬液注入層より力学的に有利であり、従って前記
従来工法に比して地盤改良薬液の注入量が少なくて済
み、同薬液の注入による地山の膨張の影響が小さく、都
市型トンネルを施工する場合には、近隣の他の構築物に
対する影響が少ない。Further, the chemical solution injection layer having a cross-sectional shape in which a plurality of branch portions are radially diverged from the central axis is mechanically advantageous over the chemical solution injection layer having a circular cross section formed in the above-mentioned conventional method, and therefore, compared with the above-mentioned conventional method. Therefore, the amount of the soil improvement chemical solution injected is small, the influence of the expansion of the natural ground due to the injection of the same chemical solution is small, and when constructing an urban tunnel, there is little effect on other nearby structures.
請求項２の発明は前記地盤改良薬液注入パイプに対する
薬液注入圧及び注入量と、前記パイプの前記削孔部から
の引抜速度を自動制御して、同削孔部の外周地盤に、中
心軸より複数の分岐部が放射状に岐出された先拡りの断
面形の地盤改良薬液層を造成し、トンネル切羽の安定を
図るものである。The invention of claim 2 automatically controls the chemical liquid injection pressure and the injection amount to the ground improvement chemical liquid injection pipe and the withdrawal speed of the pipe from the drilled portion, so that the outer peripheral ground of the drilled portion is A ground improvement chemical solution layer with a diverging cross-sectional shape in which a plurality of branches are radially diverged is created to stabilize the tunnel face.
第１図乃至第３図は本発明に係るトンネル切羽の安定工
法の一実施例の工程を示す縦断側面図、第４図は本発明
の方法で施工された切羽の状態を示す縦断側面図、第５
図はその斜視図、第６図は第４図の矢視VI−VI図、第７
図はＴ字型断面の地盤改良薬液層を示す斜視図、第８図
及び第９図は夫々地盤改良薬液注入パイプの斜視図並に
縦断面図、第10図は地盤改良薬液注入自動制御装置の系
統図、第11図乃至第13図は従来のパイプルーフ工法の工
程を示す縦断側面図、第14図及び第15図は夫々第11図並
に第12図の縦断面図、第16図及び第17図は夫々第13図の
矢視Ｘ−Ｘ図並に矢視Ｙ−Ｙ図、第18図は従来の薬液注
入工法による切羽の状態を示す縦断側面図、第19図は第
18図の矢視Ｚ−Ｚ図である。 （１）……トンネル孔、（２）……削孔機械、（３）…
…切羽、（５）……削孔部、（６）……地盤改良薬液注
入装置、（6a）……薬液注入パイプ、（８）……薬液注
入口、（９）……地盤改良薬液層、（11）……薬液注入
圧制御装置、（12）……コンプレツサー、（13）……薬
液注入パイプの引抜速度制御装置、（14）……薬液注入
量制御装置、（15）……薬液タンク、（16）……コンバ
ーター、（17）……マイクロコンピューター。1 to 3 are vertical cross-sectional side views showing the steps of one embodiment of a method for stabilizing a tunnel face according to the present invention, and FIG. 4 is a vertical cross-sectional side view showing the state of a face face constructed by the method of the present invention. Fifth
FIG. 6 is a perspective view thereof, FIG. 6 is a view VI-VI in FIG.
The figure is a perspective view showing a ground improving chemical solution layer having a T-shaped cross section, FIGS. 8 and 9 are vertical sectional views along with a perspective view of a ground improving chemical solution injection pipe, and FIG. 10 is a ground improving chemical solution automatic control device. FIG. 11 to FIG. 13 are vertical side views showing the steps of the conventional pipe roof construction method, and FIGS. 14 and 15 are vertical sectional views of FIG. 12 as well as FIG. FIG. 17 and FIG. 17 are respectively YY and Y--Y views of FIG. 13, respectively, and FIG. 18 is a vertical cross-sectional side view showing a state of a face by a conventional chemical injection method, and FIG.
FIG. 19 is a view taken along the line ZZ in FIG. (1) …… Tunnel hole, (2) …… Drilling machine, (3)…
... Face, (5) …… Drilling part, (6) …… Ground improvement chemical solution injection device, (6a) …… Chemical solution injection pipe, (8) …… Chemical solution injection port, (9) …… Ground improvement chemical solution layer , (11) …… Chemical liquid injection pressure control device, (12) …… Complexer, (13) …… Chemical liquid injection pipe withdrawal speed control device, (14) …… Chemical liquid injection amount control device, (15) …… Chemical liquid Tank, (16) …… converter, (17) …… microcomputer.
Claims (2)
主とした切羽の掘削作業において、掘削孔の外周に沿っ
て放射状に、掘削方向に対して斜め方向に削孔するとと
もに、同各削孔部に、中心軸線に対して互いに所要の角
度を以って交差する複数方向に薬液注入口が配設された
地盤改良薬液注入パイプを挿入し、前記削孔部の外周地
盤に中心軸より複数の分岐部が放射状に岐出された断面
形の薬液注入層を造成することを特徴とするトンネル切
羽の安定工法。1. In the excavation work of a face mainly made of sandy soil in tunnel construction and shield construction, the drilling is performed radially along the outer periphery of the drilling hole in an oblique direction with respect to the drilling direction, and In the hole, insert the ground improvement chemical solution injection pipe in which the chemical solution injection ports are arranged in a plurality of directions intersecting with each other at the required angle with respect to the central axis, and from the central axis to the outer ground of the drilled section. A stable construction method for a tunnel face, which is characterized by forming a chemical solution injection layer having a cross-sectional shape in which a plurality of branch portions are radially diverged.
注入圧及び注入量と、前記パイプの前記削孔部からの引
抜速度を制御して、同削孔部の外周地盤に、中心軸より
複数の分岐部が放射状に岐出された先拡りの断面形の薬
液注入層を造成する請求項１記載のトンネル切羽の安定
工法。2. A liquid injection pressure and an injection amount for the ground improvement chemical liquid injection pipe and a withdrawal speed of the pipe from the hole drilling portion are controlled to provide a plurality of holes on the outer ground of the hole drilling portion from a central axis. The method for stabilizing a tunnel face according to claim 1, wherein a chemical solution injection layer having a divergent section whose branching portion is radially extended is formed.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7404089A JPH0776509B2 (en) | 1989-03-28 | 1989-03-28 | Stabilization method of tunnel face |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7404089A JPH0776509B2 (en) | 1989-03-28 | 1989-03-28 | Stabilization method of tunnel face |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH02252891A JPH02252891A (en) | 1990-10-11 |
| JPH0776509B2 true JPH0776509B2 (en) | 1995-08-16 |
Family
ID=13535657
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP7404089A Expired - Fee Related JPH0776509B2 (en) | 1989-03-28 | 1989-03-28 | Stabilization method of tunnel face |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0776509B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0768848B2 (en) * | 1990-11-29 | 1995-07-26 | 栄興産業株式会社 | Tunnel construction method |
| CN102235151B (en) * | 2010-04-21 | 2013-05-08 | 成都中铁隆工程集团有限公司 | Advanced hole-forming method of sand gravel boulder layer |
-
1989
- 1989-03-28 JP JP7404089A patent/JPH0776509B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH02252891A (en) | 1990-10-11 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |