JPH10317878A - Mud shield method - Google Patents

Mud shield method

Info

Publication number
JPH10317878A
JPH10317878A JP13062397A JP13062397A JPH10317878A JP H10317878 A JPH10317878 A JP H10317878A JP 13062397 A JP13062397 A JP 13062397A JP 13062397 A JP13062397 A JP 13062397A JP H10317878 A JPH10317878 A JP H10317878A
Authority
JP
Japan
Prior art keywords
chamber
clay
mud
earth
pressure
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
Application number
JP13062397A
Other languages
Japanese (ja)
Inventor
Yoichi Kano
洋一 加納
Hiroshi Uehara
央 上原
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
TAC Corp
Original Assignee
TAC Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by TAC Corp filed Critical TAC Corp
Priority to JP13062397A priority Critical patent/JPH10317878A/en
Publication of JPH10317878A publication Critical patent/JPH10317878A/en
Pending legal-status Critical Current

Links

Abstract

PROBLEM TO BE SOLVED: To improve workability by a method wherein thickening liquid containing a clay coagulant and a small amount of pressure air are fed in a given state to a chamber to form an input gap for excavated earth. SOLUTION: A small amount of pressure air is fed to a chamber 2 from an air compressor 6 and a mud making material fed thereto from a mud making material preparation tank 8. During excavation of a rock layer, acrylamide is added to the mud making material to coagulate the clay content of earth and excavated earth is agitated by pressure air to form air bubbles. Through working of air bubbles gathering to the upper part of the chamber 2, excavated earth is plastically fluidized and escape of pressure air from heading to a ground is prevented from occurring. In a case of a cobble stone layer, a gap is produced in the upper part of the chamber 2 by pressure air and a mud pressure against an earth pressure and a water pressure is maintained to suppress flood on the front surface of the heading. Further, temporary internal friction is caused to occur to a ground to prevent collapse of a ground. Further, when a clay silt content is low, acrylamide is added to the mud making material to which clay bentonite is added. This constitution effects smooth cultivation and prevents filling of the chamber with earth.

Description

【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION

【0001】[0001]

【発明の属する技術分野】本発明は、シールド掘進機を
用いて地山を掘削するに際して、切羽前面の崩壊防止と
掘削された土砂の排出を効果的に行い得る加圧空隙形成
機能を付加した泥土圧式シ−ルド工法に関するものであ
る。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has a function of forming a pressurized air gap capable of effectively preventing collapse of a front face of a face and discharging excavated earth and sand when excavating a ground using a shield machine. It relates to a mud pressure type shield method.

【0002】[0002]

【従来の技術】従来、地質が砂層,砂礫層,シラス層,
シルト粘土層およびこれらの互層にてなる地山を掘削し
て隧道を建設する工事では、掘削部での掘削された土砂
を排出すると同時に、土圧や地下水圧とのバランスを保
って掘進効果を高めるために、泥水加圧式,泥水式や圧
気式などのシ−ルド工法が地山の地質に応じて適宜選択
採用されている。これら各種の方式で前述のような所謂
透水性のよい地層と不透水性の地層が混在する場合、泥
土圧式によるシールド工法が有利であるとして広く採用
されている。
2. Description of the Related Art Conventionally, the geology is sand, gravel, shirasu,
In the construction work of excavating the silt clay layer and the ground consisting of these alternate layers and constructing a tunnel, the excavated soil at the excavation part is discharged, and at the same time, the excavation effect is maintained while maintaining the balance with earth pressure and groundwater pressure. In order to increase the height, a shield method such as a mud pressurization method, a muddy water method or a pneumatic method is appropriately selected and adopted according to the geology of the ground. In these various systems, when a so-called stratum having good permeability and an impermeable stratum as described above are mixed, a shield method using a mud pressure method is widely adopted as being advantageous.

【0003】[0003]

【発明が解決しようとする課題】このような従来のシ−
ルド工法では、掘削工事現場の環境にもよるが、例えば
圧気式シールド工法による場合、切羽の全面に圧縮空気
(以下、圧気という)を供給して地山側の土圧や地下水
圧とのバランスを保って掘削することになり、地山側の
地質が変化して礫層や砂礫層のように透水性の高い地層
に達すると圧気が地盤に生じている亀裂などの間隙を縫
って流動し、予測されない場所に流出したり、掘削部で
蓄圧状態にあったのが掘進とともに地層の変化で一気に
流動して地中でのバランスを崩し、地盤の陥没事故を発
生するなどの問題があり、この種の工法の採用が次第に
減少している。
SUMMARY OF THE INVENTION Such a conventional system is disclosed.
In the field construction method, depending on the environment of the excavation work site, for example, in the case of the pneumatic shield construction method, compressed air (hereinafter referred to as “pressurized air”) is supplied to the entire face to balance the earth pressure and groundwater pressure on the ground side. When the geology on the ground side changes and reaches a highly permeable layer, such as a gravel layer or a gravel layer, pressure flows through gaps such as cracks in the ground and flows. However, there are problems such as spills into unexposed areas, and accumulation in the excavation area, which, when excavated, suddenly flows due to changes in the stratum and breaks the balance in the ground, causing collapse of the ground. The adoption of this method is gradually decreasing.

【0004】泥土加圧式(泥土圧式)シ−ルド工法によ
る場合、カッターウイングの背後に作泥室(チャンバ
ー)を形成して、この作泥室内の泥土に泥土圧を発生さ
せて切羽の土圧と地下水圧に対抗してシ−ルド掘進機の
掘削土砂の取り込み量と排土量のバランスを図りながら
掘進する方式であることから汎用されている。しかし、
この泥土加圧式シ−ルド工法の最大の弱点は、岩層(風
化花崗岩層,鉱石粘性土層など)や玉石が多く混在する
層(玉石層)である。これらの地層は、シ−ルド掘進機
のチャンバー内に土砂を充満させて土圧を保ちながら土
砂を塑性流動化させて掘削する方法では掘ることができ
ない。また、これらの地層(岩層,玉石層)ではチャン
バー内に土砂を充満させるとカッタートルクが非常に大
きくなり、掘進スピードが極端に低下する。
[0004] In the case of the mud pressurization type (mud pressure type) shield method, a mud-making chamber (chamber) is formed behind the cutter wing, and mud pressure is generated in the mud in the mud-forming chamber to make the soil pressure of the face. It is widely used because it is a method of excavating while balancing the amount of excavated earth and sand taken up by the shield excavator and the amount of excavated soil against the groundwater pressure. But,
The greatest weakness of this mud pressurized shield method is the formation of rock layers (weathered granite layer, ore clay clay layer, etc.) and layers of cobblestone (cobble layer). These formations cannot be excavated by a method in which earth is filled in the chamber of a shield machine and plastic earth is fluidized while excavating while maintaining earth pressure. Also, in these formations (rock formations, boulder formations), when the chamber is filled with earth and sand, the cutter torque becomes extremely large, and the excavation speed is extremely reduced.

【0005】前記泥土加圧式シ−ルド工法による岩層の
掘削では、切羽前面の地盤が安定しているため、シ−ル
ド掘進機のチャンバー内への土砂の取り込みは70〜8
0%以下で掘削を行っている。しかし、前記チャンバー
内では土砂を充満させていないため、排土用のスクリュ
ーコンベアへの土砂の流れ込み(土圧による押し込み)
が悪くなり、次第に掘削取り込み量と排土量とのバラン
スが崩れ、チャンバー内が密圧されてスリットやそのチ
ャンバー内に土砂が充満し閉塞する。また、岩の間から
の湧水はチャンバー内の閉塞によってどこにも行き場が
ないためにスクリューコンベアから溢れ出ることもあ
る、などの問題点がある。
In the excavation of the rock layer by the above-mentioned mud pressurized shield method, since the ground in front of the face is stable, the sediment is taken into the chamber of the shield excavator by 70 to 8 times.
Excavation is performed at 0% or less. However, since the earth and sand are not filled in the chamber, the earth and sand flows into the screw conveyor for discharging the earth (push by earth pressure).
The balance between the excavated intake amount and the earth removal amount gradually breaks down, and the inside of the chamber is tightly pressed, and the slit and the chamber are filled with earth and sand and closed. Also, there is a problem that the spring water from between the rocks may overflow from the screw conveyor because there is nowhere to go due to blockage in the chamber.

【0006】また、玉石を多く混在する地層にあって
は、通常、切羽前面の地盤は崩壊性が高く、シ−ルド掘
進機のチャンバー内を充満させていないと切羽前面で陥
没が起こる。そこで、前述のような問題点を回避するた
めに、高粘性の添加剤を大量に泥土に加えることで対応
していたが、切羽前面に大きな点岩などが出ると破砕し
た礫がチャンバー内に入りきらず、二次,三次破砕がな
されて掘削の進行が極めて低下する。同時に、カッター
ウイングに設けられるローラビット等の摩耗が激しく、
シ−ルド掘進機の維持費が高くなる、などの問題点があ
る。このようなことから、前記岩層の掘削と同様にシ−
ルド掘進機のチャンバー内を充満させずに掘削しようと
する試みもあるが、こうしたとき、地盤を陥没させる事
故が発生する危険性がある。
[0006] In a stratum where a large amount of cobblestones are mixed, the ground in front of the face is usually highly collapsible, and if the inside of the chamber of the shield machine is not filled, a depression occurs in front of the face. Therefore, in order to avoid the above-mentioned problems, a large amount of high-viscosity additive was added to the mud to cope with the problem. Secondary and tertiary crushing are carried out, and the progress of excavation is extremely reduced. At the same time, the wear of the roller bit etc. provided on the cutter wing is severe,
There are problems such as an increase in the maintenance cost of the shield machine. Therefore, similar to the excavation of rock formation,
Attempts have been made to excavate without filling the chamber of the field machine, but in such a case, there is a danger that the ground may collapse.

【0007】本発明は、このような問題点に鑑みてなさ
れたもので、シ−ルド掘進機のチャンバー内上部に空隙
が形成されるようにして、掘削された土砂の取り込みを
容易にして能率よく、かつ安全に掘進できる泥土圧式シ
−ルド工法を提供することを目的とするものである。
SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and has been made in consideration of the above-described problems. An object of the present invention is to provide a mud pressure type shield method capable of excavating well and safely.

【0008】[0008]

【課題を解決するための手段および作用・効果】前述さ
れた目的を達成するために、本発明による泥土圧式シ−
ルド工法は、シールド掘進機のチャンバー内に粘土凝集
剤を含む増粘性液を注入するとともに、少量の圧気を前
記チャンバー内上部に供給して、掘削土砂の取り込み空
隙を形成させて掘削取り込み量と排土量とのバランスを
保って掘削推進することを特徴とするものである。
In order to achieve the above-mentioned object, a mud pressure type seal according to the present invention is provided.
In the tunnel construction method, a thickening liquid containing a clay flocculant is injected into a chamber of a shield machine, and a small amount of compressed air is supplied to an upper portion of the chamber to form a cavity for taking in excavated earth and sand, thereby forming an excavated intake amount. The feature is to promote excavation while maintaining the balance with the amount of earth removal.

【0009】本発明によれば、シールド掘進機のチャン
バー内に増粘性液を注入して、作泥材の粘性を高めるこ
とにより、注入される圧気が切羽の地盤における亀裂な
どを通じての漏気を防止して、そのチャンバー内上部
に、供給される圧気による空隙を形成させることによ
り、土圧や地下水圧とのバランスを保って泥土圧式の特
性を発揮できるようになり、掘削土砂の流動排出条件を
向上させて掘削速度を高め、岩層や玉石層などでの掘削
作業を効率よく実施できることになる。
According to the present invention, by injecting the thickening liquid into the chamber of the shield machine to increase the viscosity of the sludge material, the injected pressure prevents leakage through cracks in the ground of the face. By forming a gap in the upper part of the chamber by the supplied compressed air, it is possible to maintain the balance with the earth pressure and the groundwater pressure and exhibit the characteristics of the mud soil pressure type. Therefore, the excavation speed can be increased to enhance the excavation speed, and the excavation work can be efficiently performed in a rock layer or a boulder layer.

【0010】本発明において、前記チャンバー内に供給
される増粘性液としては、粘土凝集剤あるいは粘土ベン
トナイト水溶液と粘土凝集剤を加えた溶液を用い、この
増粘性液によって掘削土中の粘土浮遊粒子の粒径を大き
くするとともに、液粘度の高い泥土液にして掘削土を不
透気性に改良し、チャンバー内上部に圧気空隙が形成さ
れるようにすることが好ましい。そして、前記粘土凝集
剤には、アクリルアミド系あるいはアルギン酸ソーダ系
の水溶液を用いるのがよい。このようにすることによ
り、少量の圧気を利用して切羽からチャンバー内に掘削
された土砂の取り込みが容易な条件を整え、しかも空隙
を形成する圧気が切羽から地盤の亀裂などを通じての漏
れ出しを確実に防止できてチャンバー内の圧力バランス
を保持させて、掘進速度を高めることが可能となる。加
えて、掘削土砂の塑性流動化を図り排土効果も向上す
る。
In the present invention, a clay coagulant or a solution obtained by adding a clay bentonite aqueous solution and a clay coagulant is used as the thickening liquid supplied into the chamber, and the clay floating particles in the excavated soil are formed by the thickening liquid. It is preferable to make the excavated soil impervious by using a muddy liquid having a high liquid viscosity, so as to form a compressed air void in the upper part of the chamber, while increasing the particle diameter of the liquid. As the clay coagulant, it is preferable to use an acrylamide-based or sodium alginate-based aqueous solution. By doing so, it is possible to prepare conditions that facilitate the incorporation of earth and sand excavated from the face into the chamber using a small amount of air, and that the air that forms the voids leaks from the face through cracks in the ground. It is possible to surely prevent the occurrence, maintain the pressure balance in the chamber, and increase the excavation speed. In addition, the excavated soil will be plastically fluidized and the soil removal effect will be improved.

【0011】また、本発明においては、崩壊性の高い地
盤の掘削時、前記チャンバー内上部に圧気を少量送入す
るとともに、粘土ベントナイトを加えた作泥材と前記粘
土凝集剤とをチャンバー内への注入口直前で混合して供
給するのが好ましい。こうすることで、粘土成分の少な
い土質の地盤に対して、土圧や地下水圧に対抗する泥土
圧を維持させて、掘削土砂の塑性流動化を図り、かつ、
送入圧気の地盤に対する漏気やスクリューコンベアから
の漏気を防止して、掘削土砂のチャンバー内への取り込
みを容易にすることができ、掘削作業の促進が可能にな
る効果を奏する。
Further, in the present invention, when excavating a highly collapsed ground, a small amount of compressed air is fed into the upper part of the chamber, and the mud material containing clay bentonite and the clay coagulant are introduced into the chamber. It is preferable to supply the mixture immediately before the injection port. By doing this, the soil soil with few clay components is maintained at the mud pressure against the soil pressure and the groundwater pressure, and the plastic fluidization of the excavated soil is achieved, and
Leakage of the incoming pressure air to the ground and leakage from the screw conveyor can be prevented, the excavated earth and sand can be easily taken into the chamber, and the excavation work can be promoted.

【0012】また、本発明においては、前記増粘性液の
粘土凝集剤としては例えばシリカゾルを水溶液にして用
い、添加する粘土ベントナイトなど沈降速度の低い微粒
子と混合させて泥土液中での凝集粒子が常時浮遊状態を
保つようにすると同時に、液の粘性を高めて注入される
圧気が液中で容積の大きい気泡を形成するようにされる
のが好ましい。こうすることで、前記同様に切羽での漏
気防止を図り、掘削速度の向上を促進することが可能に
なる。
In the present invention, as the clay flocculant of the thickening liquid, for example, silica sol is used in the form of an aqueous solution, and is mixed with fine particles having a low sedimentation rate such as clay bentonite to be added, so that the flocculated particles in the muddy liquid are removed. At the same time as maintaining the floating state at all times, it is preferable to increase the viscosity of the liquid so that the injected compressed air forms large-volume bubbles in the liquid. This makes it possible to prevent air leakage at the face as in the above, and to promote an improvement in the excavation speed.

【0013】[0013]

【発明の実施の形態】次に、本発明による泥土圧式シ−
ルド工法の具体的な実施の形態につき、図面を参照しつ
つ説明する。
DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a mud pressure type seal according to the present invention will be described.
A specific embodiment of the welding method will be described with reference to the drawings.

【0014】図1には、本発明に係る泥土圧式シ−ルド
工法の一実施態様が示されている。この実施例におい
て、泥土圧式のシ−ルド掘進機1は、カッターウイング
3を備える先端部のチャンバー2の上部に対して、その
シ−ルド掘進機1の後方に配置される小型のエアコンプ
レッサー6から配管7により少量の圧気が送り込まれる
ようにされる。また、前記チャンバー2には、公知の手
段で泥土を調整する作泥材調整槽8から配管9にて作泥
材が送り込まれるようにされる。なお、チャンバー2の
下部にはスクリューコンベア4が取り付けられ、このス
クリューコンベア4によって掘削された土砂を排出さ
せ、後方外部に送り出すようになされている。図中符号
5は推進ジャッキ、10は作泥材供給用のポンプ、11
は調整弁、12はエア調整弁である。
FIG. 1 shows an embodiment of a mud pressure type shielding method according to the present invention. In this embodiment, a mud pressure type shield excavator 1 is provided with a small air compressor 6 disposed behind the shield excavator 1 with respect to an upper part of a chamber 2 at a tip portion provided with a cutter wing 3. A small amount of compressed air is sent from the pipe 7 through the pipe. Further, the muddy material is fed into the chamber 2 through a pipe 9 from a muddy material adjusting tank 8 for adjusting mud by a known means. A screw conveyor 4 is attached to the lower part of the chamber 2 so that the earth and sand excavated by the screw conveyor 4 is discharged and sent out to the rear outside. In the figure, reference numeral 5 is a propulsion jack, 10 is a pump for supplying mud material, 11
Is an adjusting valve, and 12 is an air adjusting valve.

【0015】このようなシールド掘進機1によって岩層
(例えば風化花崗岩層,鉱石粘性土層など硬い土質の地
層)を掘削推進する場合、チャンバー2の上部にエアコ
ンプレッサー6から0.2〜0.3kgf/cm2 程度
の圧気を送り込む。この場合の圧気供給量は、例えばφ
2000mmのシ−ルド掘削で50 l/min 程度、φ4
000mmのシ−ルド掘削で200 l/min 程度の供給
が行われる。そして、前記チャンバー2に供給する作泥
材液には、作泥材調整槽8において増粘性液の粘土凝集
剤としてアクリルアミド系の液を1m3 の水に1kg程
度加え、攪拌混練したものを使用する。
When a rock layer (for example, a hard soil layer such as a weathered granite layer and an ore clay layer) is excavated and propelled by such a shield machine 1, 0.2 to 0.3 kgf is applied to the upper part of the chamber 2 from the air compressor 6. Pressure / cm 2 . The compressed air supply amount in this case is, for example, φ
Approximately 50 l / min with 2000mm shield excavation, φ4
The supply of about 200 l / min is performed by 000 mm shield excavation. The muddy liquid supplied to the chamber 2 is prepared by adding about 1 kg of an acrylamide-based liquid to 1 m 3 of water as a clay coagulant of a thickening liquid in a muddy material adjusting tank 8 and stirring and kneading the mixture. I do.

【0016】このように調整された作泥材液は、ポンプ
10によってシ−ルド掘進機1のチャンバー2内に掘削
土の20%(容積比率)程度加えることにより、掘削さ
れた土砂の粘土分を凝集させて、ちょうど和紙の繊維が
絡んだような状態にさせる。こうすることで、掘削土が
別途注入される圧気による攪乱で、その圧気が粘性の高
くなっている泥土液中に混入して大きな気泡を作り、チ
ャンバー2内で掘削土と一部混合するが重力差で気泡が
チャンバー2の上部に集まろうとする働きによって、そ
のチャンバー2内に取り込まれる掘削土を塑性流動化さ
せるとともに、その注入される圧気が切羽部分から地山
側に逃げるのを防止することになる。したがって、チャ
ンバー2内に取り込まれる掘削土は、そのチャンバー2
の下部からスクリューコンベア4によって排出され、切
羽部分に残留しないので、推進ジャッキ5によるシール
ド掘進機1の推進が促され、掘削が順調になされるので
ある。
The thus-prepared mud material liquid is added to the chamber 2 of the shield machine 1 by the pump 10 in an amount of about 20% (volume ratio) of the excavated soil, so that the excavated soil and clay are removed. Are coagulated so that the fibers of Japanese paper are tangled. By doing so, the disturbance caused by the pressure into which the excavated soil is separately injected is mixed with the muddy fluid having a high viscosity to form large bubbles, and partially mixed with the excavated soil in the chamber 2. By the action of air bubbles gathering at the upper part of the chamber 2 due to the gravity difference, the excavated soil taken into the chamber 2 is plastically fluidized, and the injected pressure is prevented from escaping from the face to the ground side. Will be. Therefore, the excavated soil taken into the chamber 2 is
Is discharged from the lower portion by the screw conveyor 4 and does not remain on the face, so that the propulsion jack 5 promotes the propulsion of the shield machine 1 and the excavation proceeds smoothly.

【0017】このようにして掘削が行われるに際して切
羽部分では、チャンバー2内に加えられる泥土圧と圧気
とによって土圧や地下水圧に平衡する圧力を付勢するこ
とで、特に粘性の高い泥土圧を加えていることにより地
山の岩の切れ目からの湧き水も阻止され、上部に移動す
る圧気の助けを借りて排土がスムーズになり、その分掘
削が容易となる。
When the excavation is performed in this manner, in the face portion, the pressure which is balanced with the earth pressure or the groundwater pressure is urged by the mud pressure and the pressure applied to the inside of the chamber 2 so that the particularly viscous mud pressure is increased. This also prevents spring water from the cuts in the rocks in the ground, and facilitates excavation with the help of the compressed air moving upward, which makes excavation easier.

【0018】以上に説明したのは岩層の地盤における掘
削の場合についてであるが、玉石を多く含む地層(玉石
層)におけるシ−ルド掘削の場合には、図2に示される
ように、シ−ルド掘進機1のチャンバー2内に別途作泥
材調整槽15で調整された作泥材をポンプ16にて配管
17を通じて供給するとともに、小型のエアコンプレッ
サー6から配管7によってチャンバー2の上部に圧気を
送り込んで、そのチャンバー2内の上部に空隙が生じる
ようにして、土圧や地下水圧に対抗する泥土圧が維持で
きるようにすることで、切羽前面の出水を抑え、地盤に
仮の内部摩擦力を生じさせることによりその地盤の崩壊
を防ぐ。また、前述のようにチャンバー2内の上部に空
隙部を形成できるようにして、上部からの圧気によるス
クリューコンベア4への排土を助けるようにすること
で、排土効率を向上させる。この結果、チャンバー2内
が土砂で充満せずして推進力を有効に与えることができ
るので、カッターウイング3の回転に過負荷が生じず運
転できることになり、カッタービットの負担が軽減され
て掘進スピードが上がり、もちろん、カッタービットの
損傷が低減して交換の度合いも少なくて経済性が一段と
高まるなどの効果を呈する。
The above description is for the case of excavation in the rocky ground. In the case of shield excavation in the formation containing a large amount of cobblestone (cobblestone layer), as shown in FIG. The mud material adjusted by the separate mud material adjusting tank 15 is supplied into the chamber 2 of the machine 1 through a pipe 17 by a pump 16, and compressed air is supplied from a small air compressor 6 to the upper part of the chamber 2 by a pipe 7. To prevent voids at the upper part of the chamber 2 and maintain the mud pressure against the earth pressure and the groundwater pressure, thereby suppressing the flooding at the front face of the face and providing temporary internal friction to the ground. The force prevents the ground from collapsing. Further, as described above, a void portion can be formed in the upper portion of the chamber 2 to assist in discharging the soil to the screw conveyer 4 by air pressure from the upper portion, thereby improving the discharging efficiency. As a result, the propulsion force can be applied effectively without filling the inside of the chamber 2 with the earth and sand, so that the operation of the cutter wing 3 can be performed without generating an overload, and the burden on the cutter bit is reduced and the excavation is performed. The speed is increased, and of course, there is an effect that the damage of the cutter bit is reduced, the degree of replacement is small, and the economic efficiency is further improved.

【0019】なお、このような玉石を多く含む地層にお
けるシ−ルド掘削の場合、掘削土砂中に粘土シルト分が
20%程度有る場合は、前述の岩層と同様に前記増粘性
液の粘土凝集剤としてアクリルアミド系の液が使用さ
れ、掘削土砂中の粘土シルト分が少ない時は、粘土と反
応するアクリルアミドを加えても効果が乏しいので、粘
土分(前述の粘土ベントナイトなど)を加えた作泥材と
別途粘土凝集剤溶解槽18にて調整のアクリルアミド系
溶解液を注入口の直前で混合して、丁度「とろろいも」
状に粘性を増した流動体を添加剤としてチャンバー2内
の泥土中に送り込む。こうすることで、土砂の塑性流動
化と漏気防止機能を発揮できるようになり、より有効な
シ−ルド掘削作業が実施できることになる。
In the case of shield excavation in a layer containing a large amount of cobblestone, if the excavated soil contains about 20% of clay silt, the clay coagulant of the thickening liquid is used as in the case of the rock layer described above. Acrylamide-based liquid is used as the material, and when the clay silt content in the excavated sediment is small, the effect of adding acrylamide that reacts with clay is poor, so the clay material with the clay content (such as the clay bentonite mentioned above) is added. Separately, the acrylamide-based solution prepared in the clay coagulant dissolution tank 18 was mixed immediately before the injection port, and the mixture was just mixed with “Tororoimo”.
The fluid having the increased viscosity is fed into the mud in the chamber 2 as an additive. By doing so, the plastic fluidization of soil and the function of preventing air leakage can be exhibited, and more effective excavation work can be performed.

【図面の簡単な説明】[Brief description of the drawings]

【図1】図1は、本発明に係る泥土圧式シ−ルド工法の
一実施態様を示す図である。
FIG. 1 is a view showing an embodiment of a mud pressure type shield method according to the present invention.

【図2】図2は、本発明に係る泥土圧式シールド工法の
他の実施例を示す概要図である。
FIG. 2 is a schematic view showing another embodiment of the mud pressure shield method according to the present invention.

【符号の説明】[Explanation of symbols]

1 シールド掘進機 2 チャンバー 3 カッターウイング 4 スクリューコンベア 5 推進ジャッキ 6 エアコンプレッサー 8,15 作泥材調整槽 9 配管 18 粘土凝集剤溶解槽 DESCRIPTION OF SYMBOLS 1 Shield machine 2 Chamber 3 Cutter wing 4 Screw conveyor 5 Propulsion jack 6 Air compressor 8,15 Mud material adjustment tank 9 Piping 18 Clay coagulant dissolution tank

Claims (4)

【特許請求の範囲】[Claims] 【請求項1】 シールド掘進機のチャンバー内に粘土凝
集剤を含む増粘性液を注入するとともに、少量の圧気を
前記チャンバー内上部に供給して、掘削土砂の取り込み
空隙を形成させて掘削取り込み量と排土量とのバランス
を保って掘削推進することを特徴とする泥土圧式シ−ル
ド工法。
1. A method for injecting a thickening liquid containing a clay coagulant into a chamber of a shield machine and supplying a small amount of compressed air to an upper portion of the chamber to form a cavity for taking in excavated earth and sand, thereby forming an excavated amount. And excavation while maintaining the balance between earth removal and earth removal.
【請求項2】 前記チャンバー内に供給される増粘性液
として粘土ベントナイト水溶液と粘土凝集剤を加えた溶
液を用い、この増粘性液によって掘削土中の粘土浮遊粒
子の粒径を大きくするとともに、液粘度の高い泥土液に
して掘削土を不透気性に改良し、チャンバー内上部に圧
気空隙が形成されるようにすることを特徴とする請求項
1に記載の泥土圧式シ−ルド工法。
2. A method in which a clay bentonite aqueous solution and a clay coagulant are added as a thickening liquid to be supplied into the chamber, and the thickening liquid increases the particle diameter of suspended clay particles in the excavated soil, The method according to claim 1, wherein the excavated soil is made impermeable by using a muddy liquid having a high liquid viscosity so that a pressurized air gap is formed in an upper part of the chamber.
【請求項3】 前記チャンバー内に供給される増粘性液
の粘土凝集剤としてはアクリルアミド系あるいはアルギ
ン酸ソーダ系の水溶液を用い、この粘土凝集剤の水溶液
によって掘削土中の粘土浮遊粒子の粒径を大きくすると
ともに、液粘度の高い泥土液にして掘削土を不透気性に
改良し、チャンバー内上部に圧気空隙が形成されるよう
にすることを特徴とする請求項1に記載の泥土圧式シ−
ルド工法。
3. A clay coagulant for the thickening liquid supplied into the chamber is an aqueous solution of acrylamide or sodium alginate, and the aqueous solution of the clay coagulant is used to reduce the particle size of the suspended clay particles in the excavated soil. The mud pressure type seal according to claim 1, wherein the excavated soil is made impermeable by increasing the size of the mud and having a high liquid viscosity, so that a pressurized air gap is formed in the upper part of the chamber.
Ludo method.
【請求項4】 崩壊性の高い地盤の掘削時、前記チャン
バー内上部に圧気を少量送入するとともに、粘土ベント
ナイトを加えた作泥材と前記粘土凝集剤とをチャンバー
内への注入口直前で混合して供給することを特徴とする
請求項1乃至3のいずれかに記載の泥土圧式シールド工
法。
4. Excavation of highly collapsed ground, a small amount of compressed air is fed into the upper part of the chamber, and the mud material added with clay bentonite and the clay coagulant are added immediately before injection into the chamber. The mud pressure shield method according to any one of claims 1 to 3, wherein the mixture is supplied in a mixed manner.
JP13062397A 1997-05-21 1997-05-21 Mud shield method Pending JPH10317878A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP13062397A JPH10317878A (en) 1997-05-21 1997-05-21 Mud shield method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP13062397A JPH10317878A (en) 1997-05-21 1997-05-21 Mud shield method

Publications (1)

Publication Number Publication Date
JPH10317878A true JPH10317878A (en) 1998-12-02

Family

ID=15038670

Family Applications (1)

Application Number Title Priority Date Filing Date
JP13062397A Pending JPH10317878A (en) 1997-05-21 1997-05-21 Mud shield method

Country Status (1)

Country Link
JP (1) JPH10317878A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107387105A (en) * 2017-08-11 2017-11-24 中交天和机械设备制造有限公司 EPB shield tunneling bentonite pressurize device and method
CN110924967A (en) * 2019-11-27 2020-03-27 中建五局土木工程有限公司 Fine control construction method for shield proximity sensitive building in water-rich sandy gravel stratum
JP2020190090A (en) * 2019-05-20 2020-11-26 大成建設株式会社 Slurry type shield construction method

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107387105A (en) * 2017-08-11 2017-11-24 中交天和机械设备制造有限公司 EPB shield tunneling bentonite pressurize device and method
CN107387105B (en) * 2017-08-11 2023-12-22 中交天和机械设备制造有限公司 Soil pressure shield bentonite pressure maintaining equipment and method
JP2020190090A (en) * 2019-05-20 2020-11-26 大成建設株式会社 Slurry type shield construction method
CN110924967A (en) * 2019-11-27 2020-03-27 中建五局土木工程有限公司 Fine control construction method for shield proximity sensitive building in water-rich sandy gravel stratum

Similar Documents

Publication Publication Date Title
CN101191417A (en) Bentonite mud water pressurization equilibration shield machine
CN104481549B (en) Bentonite injection method and system for blocking gushing water and sand
JPH10317878A (en) Mud shield method
CN208918541U (en) A kind of device for abolishing cutterhead mud cake
CN113026848B (en) Construction method of continuous high-spraying impervious wall by planing and milling method
JP2000274184A (en) Laying method for inground buried pipeline
JPH0828200A (en) Filling of space part
JP4555911B2 (en) Low noise, low vibration sediment pump additive and sediment pump pumping method
JP2519017B2 (en) Shielding method with bubbles and siliceous paste
JPH10511155A (en) Metal surface lubricant and lubrication method for earth pressure tunnel excavator
JP3168501B2 (en) Shielding method for Dotan layer
JP2003239686A (en) Pipe-jacking shield method and pipe-jacking shield machine
JP3003538B2 (en) Construction method of mud solidification wall
JPH10169365A (en) Method of shield tunneling method for weak soil and drilling-fluid additive
JPS62141220A (en) Ground improving work
JPH04203093A (en) Sludge pressure type shield machine
CN103396807A (en) Intelligent muck suspending agent
JP3150298B2 (en) Tunnel excavation method and shield machine
JP3124368B2 (en) Earth pressure shield excavation method
JPS59213897A (en) Shield drilling apparatus
JP2001207436A (en) Slurry composition
JPH11241593A (en) Ground collapse preventing method in shield construction
JPH07116909B2 (en) Water pressure balance type pumping and discharging shield method and shield machine
JPS61137994A (en) Soil pressure shield excavation method
JPS62125196A (en) Soil pressure shield excavating method using muddy slurry

Legal Events

Date Code Title Description
A02 Decision of refusal

Free format text: JAPANESE INTERMEDIATE CODE: A02

Effective date: 20040331