JP3634746B2

JP3634746B2 - Ground injection device and injection method

Info

Publication number: JP3634746B2
Application number: JP2000390276A
Authority: JP
Inventors: 俊介島田; 完洋矢口
Original assignee: Hara Kougyou Co Ltd
Current assignee: Hara Kougyou Co Ltd
Priority date: 2000-12-22
Filing date: 2000-12-22
Publication date: 2005-03-30
Anticipated expiration: 2020-12-22
Also published as: JP2002188141A

Description

【０００１】
【発明の属する技術分野】
本発明は地盤注入液を地盤中に設置された注入管路を通して地盤中に注入し、該地盤を固結する地盤注入装置および工法に係り、特に注入の際の圧力変化にもかかわらず、所定の吐出量で注入し得る地盤注入装置および工法に係り、詳細には、地盤中に設置した複数の注入管路に同時に注入したときに、それぞれの注入管路の地盤の注入抵抗圧力に違いがあっても、所定の吐出量で同時に注入し得る地盤注入装置および工法に係り、さらに詳細には、複数の注入管路に同時に注入したときに、これらの注入管路のうちの一部が先に注入を停止しても、他の注入管路の注入圧力に影響を与えることなく、所定の吐出量で同時注入が続行され、あるいはこれらの注入管路のうちの一部の注入が変化した場合、その注入管路のみを所望の圧力または吐出速度に変動させて所定量の注入を可能とする地盤注入装置および工法に関する。
【０００２】
【従来の技術】
地盤中に注入液を注入して該地盤を改良する地盤改良技術として、従来、注入すべき地盤に注入管を設置し、これら注入管を一本づつ下方から上方に引き上げ、あるいは上方から下方に押し下げて注入ステージを移向しながら注入する方法が知られている。
【０００３】
【発明が解決すべき課題】
しかし、注入すべき対象地盤は大方、軟弱な沖積層であって、透水性の異なる土層が積層して構成されており、このため、注入ステージを移向させながらそれぞれの土層に最適な注入を達成すること、すなわち、最適な注入圧、注入速度、注入量、注入率等による注入を達成することは極めて煩雑であって、長時間を必要とし、不経済となり、実質的に不可能であった。
【０００４】
また、近年、地盤注入により液状化防止を行なうことが要求されている。このような液状化防止には大容量土の経済的急速施工が必要である。しかし、従来の注入工法ではこのような急速施工は不可能であった。
【０００５】
特に、地盤は上述のとおり、透水性の異なる土層が積層して構成されており、このため、各土層間で注入圧が異なって圧力変化を起こし、あるいは注入中に注入圧力の変化を起こし、この地盤内圧力変化のため一定量の吐出量で地盤注入することは非常に困難であった。また、地盤中に設置した複数の注入管路に一つのポンプから同時に注入する場合、各注入管路吐出口の地盤の注入圧力が異なれば、圧力の低い注入管路のみに注入液が吐出され、所定の注入量を複数の注入管路に同時に注入することは不可能であった。
【０００６】
また、一台のポンプから多数のオリフイスまたは噴射口を介して多数の注入管に同時に注入液を送液し、地盤中に注入する方法も提案されている。この方法では個々の注入管について、地盤の抵抗圧の変化の幅が大きい場合、それぞれの注入管毎の注入圧力、注入量を変動させて所定注入量の注入を行なうことは困難である。また、多数の注入管のうち、いずれかの注入管の注入が終了してのち、残りの注入管からの注入を所定圧力および吐出量を保ちながら注入することもまた困難なため、実用化には至っていないのが実情である。
【０００７】
例えば、複数の注入管のうち、一部の注入管の注入が完了してこの注入管路のバルブを閉束した場合、送液管内の圧力は急上昇して残りの注入管への注入量が急激に増大してしまい、一定の注入圧力で一定の注入量を維持して注入を継続することが困難になる。また、各注入管毎に注入管からの吐出量を注入状況に応じて変動させることも困難である。
【０００８】
そこで、本発明の目的は地盤注入の際の注入圧力の変化にもかかわらず、所定の吐出量で注入し得、また、複数の注入管路吐出口の浸透抵抗圧力がそれぞれ異なっても、複数の注入管路から同時に、所定の注入速度で注入し得、さらに、複数の注入管路のうち、一部の注入が完了して注入を停止しても、他の残りの注入管路に影響を与えず、所定の圧力および吐出量を保ったまま、最後の一本の注入管路まで容易に注入し得、さらにまた、注入中、各注入管路毎にその吐出量を注入状況に応じて調整し得、上述公知技術に存する欠点を改良した地盤注入装置および工法を提供することにある。
【０００９】
さらに、本発明の他の目的は液状化防止工事あるいは大規模工事における急速施工のための地盤改良等、大容量土の地盤改良に適し、特に、改良すべき地盤に複数の注入管路を設置し、これら複数の注入管路から注入液を同時に、かつ選択的に、さらには自動的に注入し得る地盤注入装置および工法を提供することにある。
【００１０】
【課題を解決するための手段】
上述の目的を達成するため、本発明によれば、地盤注入液を地盤中に設置された注入管路を通して地盤中に注入し、該地盤を固結する地盤注入装置において、該注入液を加圧する注入液加圧部と、この注入液加圧部に連通され、前記加圧部によって加圧された注入液を前記複数の注入管路にそれぞれ送液する複数の分岐管とを備え、前記複数の分岐管にはそれぞれ、注入液リターン装置および、これよりも下流側に圧力計および／または流量計が設けられ、前記注入液リターン装置は圧力計および／または流量計からの情報に基づき、分岐管中の前記注入液を分岐管から分流することにより、分岐管中の液圧を所望の圧力に保持し、これにより各分岐管から注入管路に送液される注入液の吐出量および／または吐出圧力を所望の範囲に保持するとともに、複数の分岐管のいずれかが注入を停止しても、残りの各分岐管の吐出量および／または吐出圧力を所望の範囲に保持し、あるいは、各分岐管毎に所定の圧力または吐出速度に変動させることを特徴とする。
【００１１】
さらに上述の目的を達成するため、本発明によれば、地盤注入液を地盤中に設置された複数の注入管路を通して地盤中に注入し、該地盤を固結する地盤注入工法において、該注入液を加圧する注入液加圧部と、この注入液加圧部に連通され、前記加圧部によって加圧された注入液を前記複数の注入管路にそれぞれ送液する複数の分岐管と、前記複数の分岐管にそれぞれ設けられた注入液リターン装置およびこれより下流側の分岐管に設けられた圧力計および／または流量計と、前記圧力計および／または流量計に接続されてこれらからの情報を受け、かつ注入液リターン装置に接続され、前記情報に基づいてリターン装置に指示を与える流量圧力制御装置とを備えた地盤注入装置を用い、前記注入液を注入加圧部から分岐管および注入管路を経て地盤中に注入するに際して、この注入を注入液リターン装置に分流の指示を与えながら行って分岐管中の液圧を所望の圧力に保持することを特徴とし、これにより各分岐管から注入管路に送液される注入液の吐出量および／または吐出圧力を所望の範囲に保持するとともに、複数の分岐管のいずれかが注入を停止しても、残りの各分岐管の吐出量および／または吐出圧力を所望の範囲に保持し、あるいは、各分岐管毎に所定の圧力または吐出速度に変動させることを特徴とする。
【００１２】
【発明の実施の態様】
以下、本発明を添付図面を用いて詳述する。
【００１３】
図１は本発明にかかる地盤注入装置の一具体例のフローシートである。図２は本発明にかかる地盤注入装置の他の具体例のフローシートである。図３は本発明にかかる地盤注入装置のさらに他の具体例のフローシートである。図４は注入液加圧部として複数台の注入ポンプを用いたときのフローシートである。
【００１４】
図１において、地盤注入装置Ａは注入液槽４中の地盤注入液５を地盤３中に設置された複数の注入管路２、２・・・２を通して地盤３中に注入し、地盤３を固結する。このような本発明にかかる地盤注入装置Ａは注入液加圧部１と、複数の分岐管６、６・・・６とを基本的に備えて構成される。
【００１５】
注入液加圧部１は注入液槽４と導管（送液系１３）を介して連結され、槽４中の地盤注入液５を注入液加圧部１に導き入れ、加圧する。この注入液加圧部１は具体的には例えば、一台の注入ポンプから構成され、あるいは図４に示されるように、複数台の注入ポンプ１２、１２・・・１２を並列して構成され、さらには図示しないがコンプレッサから構成される。
【００１６】
分岐管６、６・・・６はそれぞれ送液系１３を介して注入液加圧部１に連通され、注入液加圧部１によって加圧された注入液を注入管路２、２・・・２に送液する。これら分岐管６、６・・・６にはそれぞれ、注入液リターン装置７（例えば、図１に示される三方コック）およびこれよりも下流側に圧力計８および／または流量計９が設けられる。１４は地盤３中の注入管路２と、分岐管６とを連結する連結部である。
【００１７】
本発明にかかる地盤注入装置Ａはさらに、図１に示されるように、流量圧力制御装置１０を備える。この流量圧力制御装置１０は図１の装置の例ではそれぞれの分岐管６、６・・・６に備えられ、各分岐管６の圧力計８および／または流量計９に接続されてこれらの情報を受ける。さらに、流量圧力制御装置１０は注入液リターン装置７に接続され、圧力計８および／または流量計９からの情報に基づいてリターン装置７に指示を与える。
【００１８】
リターン装置７は流量圧力制御装置１０からの指示を受け、分岐管６中に送液中の注入液が所定の圧力範囲および／または瞬時流量範囲を保持するように、注入液を分岐管６からリターン管路１１に分流して注入液槽４中にもどし、分岐管６の液圧を所望の圧力範囲および／または瞬時流量範囲に保持する。
【００１９】
すなわち、注入液槽４中の注入液５は送液系１３を介し、注入液加圧部１から分岐管６を経て注入管路２から地盤３中に注入されるが、この際、注入液リターン装置７に分流の指示を与えながら注入を行なって分岐管６中の液圧を所望の圧力範囲および／または瞬時流量範囲に保持する。
【００２０】
注入液５は注入液加圧部１を経て送液系１３に加圧送液され、次いで、分岐管６に設置されたリターン装置７（三方コック７）で流路がしぼられる。三方コック７の流路の断面をＡとすると、流路Ａを流れる注入液５の瞬時流量ｑは三方コック７よりも上流側の圧力Ｐ_０（注入液加圧部１による送液系１３の圧力）と注入管路２内圧力Ｐ_１（地盤注入圧）の差圧△Ｐ＝Ｐ_０−Ｐ_１によって定まる。差圧△Ｐが大きいほど、また、流路Ａが大きいほど、瞬時流量ｑは大きくなる。また、△Ｐがゼロに近づくにつれてｑはゼロに近づく。
【００２１】
したがって、地盤注入圧Ｐ_１が注入経過とともに変動して注入圧力が上昇し、△Ｐが小さくなっても流路Ａを大きくすることによって瞬時流路ｑを所定範囲に保つことができ、あるいは流路Ａを大きくすることによって瞬時流路を小さくし、Ｐ_１の上昇を抑えて地盤の変状を少なくすることができる。
【００２２】
そして、これらの調整を各分岐管６毎に行なうことができる。すなわち、本発明によれば、注入加圧部１の圧力と、三方コック７の調整による三方コック７内の流路Ａの開度を変動することにより、個々の分岐管６毎に、注入状況に応じて注入圧力、瞬時注入量の調整が可能であり、所定注入量を地盤変位を最小限にして注入することが可能となる。
【００２３】
具体的には、流量圧力制御装置１０に所望の圧力値および／または流量値を設定しておき、この状態で、圧力計８および／または流量計９から実際の圧力値および／または流量値を流量圧力制御装置１０に送る。リターン装置７、すなわち、三方コック７には図示しないが、リバーシブルモータが内在し、流量圧力制御装置１０の指示により実際の圧力値および／または流量値が設定値に近付き、かつ同じ値を保つように、リバーシブルモータを正転あるいは逆転し、シヤフトを上下して三方コック７の開度を調整してリターン管路１１への分流量（リターン量）を調整する。
【００２４】
なお、本発明において、流量圧力制御装置１０と、圧力計８および／または流量計９と、リターン装置７（三方コック７）とを一体化して流量圧力制御装置１０として用いることもできる。
【００２５】
これにより、各分岐管６から注入管路２に送液される注入液の吐出量および／または吐出圧力は所望の範囲に保持されるのみならず、複数の分岐管６、６・・・６のいずれかが注入を停止しても、残りの各分岐管６の吐出量および／または吐出圧力もまた、所望の範囲に保持される。
【００２６】
図２は流量圧力制御装置１０を一個備えた例である。この場合、複数の分岐管６の圧力計８および／または流量計９は一個所の流量圧力制御装置１０に接続されるとともに、この一個所の流量圧力制御装置１０からそれぞれのリターン装置７に指示を与える。したがって、流量圧力制御装置１０は一個で済むので装置が簡略化される。
【００２７】
図３は図２の装置において、さらに送液系１３、すなわち、注入液加圧部１から分岐管６に至る途中の導管にも、注入液リターン装置７ａおよび、これよりも下流側に圧力計８ａおよび／または流量計９ａを設けるとともに、これら注入液リターン装置７ａ、および圧力計８ａあるいは流量計９ａをそれぞれ流量圧力制御装置１０に接続した例である。この場合、注入液リターン装置７ａは圧力計８ａおよび／または流量計９ａからの情報に基づき、送液系１３中の注入液を送液系１３からリターン管路１１に分流することにより送液系１３の液圧を所望の圧力に保持する。この場合も、注入液リターン装置７、圧力計８ａおよび／または流量計９ａ、および流量圧力制御装置１０を一体化して流量圧力制御装置１０とすることもできる。
【００２８】
これにより、注入液が分岐管６に導入される以前の送液系１３の段階で送液系１３から分岐管６に送液される注入液の吐出量および／または吐出圧力を所望の範囲に保持し得る。
【００２９】
この場合、注入加圧部１で加圧された送液系１３の流圧は注入液リターン装置７によって圧力流量制御装置１０で指示された一定圧Ｐ_０を保持する。各分岐管６の注入圧力Ｐ_ｉとの差圧△Ｐ_ｉ＝Ｐ_０−Ｐ_ｉを充分に保持するようにＰ_０と、各分岐管６の三方コック７の流路断面Ａ_ｉとを選定すれば、差圧△Ｐ_ｉと流路断面Ａ_ｉによって各注入管路２の瞬時吐出量が保持できる。
【００３０】
注入過程中で注入圧力Ｐ_ｉが変動して差圧△Ｐ_ｉが変化した場合、流量断面Ａ_ｉを変動することによって該当する注入管路２の瞬時流量ｑ_ｉを所定範囲に保つことができ、あるいは差圧△Ｐ_ｉが所定の範囲を保つように流路断面Ａ_ｉを変動して地盤の変位を最小限に抑えることができる。
【００３１】
したがって、各分岐管６から注入管路２に送液される注入液の吐出量および／または吐出圧力は一層正確に所望の範囲に保持されるとともに、複数の分岐管６のいずれかが注入を停止しても、残りの各分岐管６の吐出量および／または吐出圧力もまた、一層正確に所望の範囲に保持される。
【００３２】
本発明に用いられる地盤注入液５は次のａ）〜ｆ）に示される注入液から任意に選択される。これらの注入液５はいずれもゲル化時間を十数時間に設定できるので、大量の注入液をつくって置いてもゲル化の心配がないのみならず、大量の注入液を長時間かけて送液でき、かつ地盤中に注入した後、確実にゲル化し、さらに粘性が小さく、ねばりが少ないため、リターン装置７の三方コックにシリカゲルが詰まることがなく、本発明装置に用いられる地盤注入液として極めて優れたものである。また、セメント、スラグ等の懸濁性注入液もまた、ねばりが少ないので、三方コックに詰まり難く、本発明に適している。また、本発明装置を複数セットで用い、それぞれ主材、反応剤を別々に分岐管を通して送液し、注入管内で合流するか、あるいは地盤中に吐出後反応させれば、全ての注入材を注入することができる。
【００３３】
ａ）水ガラス中のアルカリの一部または全部をイオン交換樹脂またはイオン交換膜で除去して得られるシリカ溶液を主材とした注入液。
【００３４】
ｂ）水ガラスのアルカリを酸で中和して得られる非アルカリ領域のシリカ溶液を主材とした注入液。
【００３５】
ｃ）水ガラスをイオン交換によってアルカリを除去し、得られたシリカを造粒したコロイダルシリカを主材とした注入液。
【００３６】
ｄ）水ガラスのアルカリを除去して得られるシリカ溶液に水ガラスおよび／またはコロイダルシリカを添加してなるシリカ溶液を主材とした注入液。
【００３７】
ｅ）水ガラスと、コロイダルシリカと、反応剤とを混合してなるシリカ溶液を主材とした注入液。
【００３８】
ｆ）懸濁性注入液。
【００３９】
【発明の効果】
以上のとおり、本発明は地盤注入液を地盤中に設置された複数の注入管路を通して地盤中に注入し、該地盤を固結するに際して、該注入液を加圧する注入液加圧部と、この注入液加圧部に連結され、前記加圧部によって加圧された注入液を前記複数の注入管路にそれぞれ送液する複数の分岐管と、前記複数の分岐管にそれぞれ設けられた注入液リターン装置およびこれより下流側の分岐管に設けられた圧力計および／または流量計と、前記圧力計および／または流量計に接続されてこれらからの情報を受け、かつ注入液リターン装置に接続されてこれら情報に基づいてリターン装置に指示を与える流量圧力制御装置とを備えた地盤注入装置を用いて地盤注入を行なう。
【００４０】
このため、前記注入液を注入液加圧部から分岐管を経て注入管路から地盤中に注入するに際して、この注入を注入液リターン装置に分流の指示を与えながら行なって分岐管中の液圧を所望の圧力に保持し得る。
【００４１】
したがって、各分岐管から注入管路に送液される注入液の吐出量および／または吐出圧力を所望の範囲に保持するとともに、複数の分岐管のいずれかが注入を停止しても、残りの各分岐管の吐出量および／または吐出圧力を所望の範囲に保持する。
【図面の簡単な説明】
【図１】本発明にかかる地盤注入装置の一具体例のフローシートである。
【図２】本発明にかかる地盤注入装置の他の具体例のフローシートである。
【図３】本発明にかかる地盤注入装置のさらに他の具体例のフローシートである。
【図４】注入液加圧部として複数台の注入ポンプを用いたフローシートである。
【符号の説明】
Ａ地盤注入装置
１注入液加圧部
２注入管路
３地盤
４注入液槽
５地盤注入液
６分岐管
７リターン装置
７ａリターン装置
８圧力計
８ａ圧力計
９流量計
９ａ流量計
１０流量圧力制御装置
１１リターン管路
１２注入ポンプ
１３送液系
１４連結部[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a ground injecting apparatus and method for injecting a ground injecting solution into an earth through an infusion line installed in the ground, and solidifying the ground. In particular, there is a difference in the injection resistance pressure of the ground of each injection pipe when it is injected simultaneously into a plurality of injection pipes installed in the ground. In particular, the present invention relates to a ground injecting apparatus and method capable of injecting simultaneously at a predetermined discharge amount, and more specifically, when injecting simultaneously into a plurality of injecting lines, some of these injecting lines first. Even if the injection is stopped, simultaneous injection is continued with a predetermined discharge amount without affecting the injection pressure of other injection lines, or some of these injection lines are changed. If only the injection line is at the desired pressure or Varied in speed out to about ground injection apparatus and method enabling the injection of a predetermined amount.
[0002]
[Prior art]
As a ground improvement technique for improving the ground by injecting an injection solution into the ground, conventionally, injection pipes are installed on the ground to be injected, and these injection pipes are pulled up from the bottom one by one, or from the top to the bottom. A method of injecting while pushing down and moving the injection stage is known.
[0003]
[Problems to be Solved by the Invention]
However, the target ground to be injected is mostly soft alluvium, which is composed of soil layers with different water permeability, which is optimal for each soil layer while turning the injection stage. Achieving injection, that is, achieving injection with optimal injection pressure, injection rate, injection volume, injection rate, etc. is extremely cumbersome, requires a long time, becomes uneconomical and virtually impossible Met.
[0004]
In recent years, it has been required to prevent liquefaction by ground injection. In order to prevent such liquefaction, an economical and rapid construction of large-capacity soil is necessary. However, such rapid construction was not possible with the conventional injection method.
[0005]
In particular, as described above, the ground is formed by laminating soil layers with different water permeability. For this reason, the injection pressure varies between the soil layers, or the injection pressure changes during the injection. Because of this pressure change in the ground, it was very difficult to inject the ground with a fixed discharge amount. In addition, when simultaneously injecting from a single pump into a plurality of injection pipes installed in the ground, if the injection pressure of the ground at each injection pipe discharge port is different, the injection liquid is discharged only to the low-pressure injection pipes. It was impossible to simultaneously inject a predetermined injection amount into a plurality of injection lines.
[0006]
There has also been proposed a method in which an injection solution is simultaneously fed from a single pump to a large number of injection pipes via a large number of orifices or injection ports and injected into the ground. In this method, when the width of the change in the resistance pressure of the ground is large for each injection pipe, it is difficult to inject a predetermined injection quantity by changing the injection pressure and the injection quantity for each injection pipe. In addition, it is difficult to inject the injection from the remaining injection tubes after maintaining the predetermined pressure and discharge amount after the injection of one of the many injection tubes is completed. The situation is not reached.
[0007]
For example, when the injection of some of the plurality of injection pipes is completed and the valves of the injection pipes are closed, the pressure in the liquid supply pipe rises rapidly and the injection amount to the remaining injection pipes It suddenly increases, making it difficult to maintain the constant injection volume at a constant injection pressure and continue the injection. It is also difficult to vary the discharge amount from the injection tube for each injection tube according to the injection status.
[0008]
Therefore, the object of the present invention is to be able to inject at a predetermined discharge amount regardless of the change of the injection pressure at the time of ground injection, and even if the permeation resistance pressures of the plurality of injection pipe discharge ports are different, a plurality of Can be injected at the same injection rate from one injection line at the same time, and even if some injections are completed and the injection is stopped, other remaining injection lines are affected. Can be easily injected up to the last single injection line while maintaining the specified pressure and discharge volume, and during injection, the discharge volume for each injection line depends on the injection situation. It is an object of the present invention to provide a ground injection device and method that can be adjusted and improved with the above-mentioned drawbacks of the known technology.
[0009]
Furthermore, another object of the present invention is suitable for ground improvement of large-capacity soil, such as ground improvement for liquefaction prevention construction or rapid construction in large-scale construction, and in particular, a plurality of injection pipes are installed in the ground to be improved. It is another object of the present invention to provide a ground injection device and method capable of simultaneously, selectively, and automatically injecting an injection from a plurality of injection pipes.
[0010]
[Means for Solving the Problems]
In order to achieve the above-mentioned object, according to the present invention, the ground injection solution is injected into the ground through an injection pipe installed in the ground, and the injection solution is added to the ground injection device that consolidates the ground. An infusate pressurizing unit that pressurizes, and a plurality of branch pipes that communicate with the infusate pressurizing unit and feed the infusate pressurized by the pressurizing unit to the plurality of injection conduits, respectively. Each of the plurality of branch pipes is provided with an infusion solution return device and a pressure gauge and / or a flow meter downstream thereof, and the infusion solution return device is based on information from the pressure meter and / or the flow meter, By diverting the injection liquid in the branch pipes from the branch pipes, the liquid pressure in the branch pipes is maintained at a desired pressure, whereby the discharge amount of the injection liquid sent from each branch pipe to the injection pipe line and / Or keep the discharge pressure in the desired range In addition, even if any of the plurality of branch pipes stops injection, the discharge amount and / or discharge pressure of each remaining branch pipe is maintained within a desired range, or a predetermined pressure or discharge is applied to each branch pipe. It is characterized by varying the speed.
[0011]
Furthermore, in order to achieve the above-mentioned object, according to the present invention, in the ground injection method for injecting the ground injection solution into the ground through a plurality of injection pipes installed in the ground, the ground is consolidated. An infusion liquid pressurizing unit that pressurizes the liquid, and a plurality of branch pipes that are in communication with the infusion liquid pressurizing part and that feed the infusate pressurized by the pressurization part to the plurality of injection pipes, respectively. An infusate return device provided in each of the plurality of branch pipes and a pressure gauge and / or a flow meter provided in the branch pipe on the downstream side thereof, and connected to and from the pressure gauge and / or flow meter A ground injection device that receives information and is connected to an injection solution return device and has a flow rate and pressure control device that gives an instruction to the return device based on the information. Injection line When injecting into the ground, this injection is performed while giving an instruction of the diversion to the injection liquid return device, and the liquid pressure in the branch pipe is maintained at a desired pressure. While maintaining the discharge amount and / or discharge pressure of the injection liquid fed to the channel in a desired range, even if any of the plurality of branch pipes stops injection, the discharge amount and / or the remaining branch pipes Alternatively, the discharge pressure is maintained in a desired range, or is changed to a predetermined pressure or discharge speed for each branch pipe.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.
[0013]
FIG. 1 is a flow sheet of a specific example of a ground injection device according to the present invention. FIG. 2 is a flow sheet of another specific example of the ground injection device according to the present invention. FIG. 3 is a flow sheet of still another specific example of the ground injection device according to the present invention. FIG. 4 is a flow sheet when a plurality of infusion pumps are used as the infusate pressurizing unit.
[0014]
In FIG. 1, the ground injection device A injects the ground injection solution 5 in the injection solution tank 4 into the ground 3 through a plurality of injection pipes 2, 2... 2 installed in the ground 3. Consolidate. Such a ground injection device A according to the present invention basically includes the injection liquid pressurizing unit 1 and a plurality of branch pipes 6, 6.
[0015]
The injection liquid pressurizing unit 1 is connected to the injection liquid tank 4 via a conduit (liquid feeding system 13), and the ground injection liquid 5 in the tank 4 is introduced into the injection liquid pressurizing part 1 and pressurized. Specifically, the infusate pressurizing unit 1 is composed of, for example, a single infusion pump, or a plurality of infusion pumps 12, 12... 12 in parallel as shown in FIG. Further, although not shown, it is composed of a compressor.
[0016]
The branch pipes 6, 6... 6 communicate with the injection liquid pressurizing unit 1 through the liquid supply system 13, respectively, and the injection liquid pressurized by the injection liquid pressurizing unit 1 is supplied to the injection pipes 2, 2.・ Transfer to 2. Each of the branch pipes 6, 6... 6 is provided with an injection liquid return device 7 (for example, a three-way cock shown in FIG. 1) and a pressure gauge 8 and / or a flow meter 9 on the downstream side thereof. Reference numeral 14 denotes a connecting portion that connects the injection pipe 2 in the ground 3 and the branch pipe 6.
[0017]
The ground injection device A according to the present invention further includes a flow rate pressure control device 10 as shown in FIG. In the example of the apparatus shown in FIG. 1, this flow pressure control device 10 is provided in each branch pipe 6, 6... 6, and is connected to the pressure gauge 8 and / or flow meter 9 of each branch pipe 6 to receive these information. Receive. Further, the flow rate pressure control device 10 is connected to the infusate return device 7 and gives an instruction to the return device 7 based on information from the pressure gauge 8 and / or the flow meter 9.
[0018]
The return device 7 receives an instruction from the flow rate pressure control device 10, and injects the injection solution from the branch tube 6 so that the injection solution being fed in the branch tube 6 maintains a predetermined pressure range and / or instantaneous flow rate range. The flow is diverted to the return pipe 11 and returned to the injection liquid tank 4, and the hydraulic pressure of the branch pipe 6 is maintained within a desired pressure range and / or instantaneous flow rate range.
[0019]
That is, the injection solution 5 in the injection solution tank 4 is injected from the injection solution pressurizing unit 1 through the branch pipe 6 into the ground 3 through the injection line 2 through the liquid supply system 13. Injection is performed while giving an instruction for diversion to the return device 7, and the hydraulic pressure in the branch pipe 6 is maintained within a desired pressure range and / or instantaneous flow rate range.
[0020]
The injection solution 5 is pressurized and fed to the solution delivery system 13 via the injection solution pressurizing unit 1, and then the flow path is squeezed by a return device 7 (three-way cock 7) installed in the branch pipe 6. Assuming that the cross section of the flow path of the three-way cock 7 is A, the instantaneous flow rate q of the injection liquid 5 flowing through the flow path A is the pressure P ₀ upstream of the three-way cock 7 (of the liquid supply system 13 by the injection liquid pressurizing unit 1). Pressure) and the pressure P ₁ (ground injection pressure) in the injection pipe line 2 is determined by the differential pressure ΔP = P ₀ −P ₁ . The larger the differential pressure ΔP and the larger the flow path A, the larger the instantaneous flow rate q. Further, q approaches zero as ΔP approaches zero.
[0021]
Thus, soil injection pressure P ₁ is varied with injection elapsed injection pressure is increased, △ P instantaneous channel q can be kept in a predetermined range by the increase the flow path A even smaller, or flow to reduce the instantaneous flow path by increasing the road a, it is possible to reduce the Deformation of soil by suppressing the increase of P _1.
[0022]
These adjustments can be made for each branch pipe 6. That is, according to the present invention, by varying the pressure of the injection pressurizing unit 1 and the opening degree of the flow path A in the three-way cock 7 by adjusting the three-way cock 7, the injection situation is determined for each branch pipe 6. The injection pressure and the instantaneous injection amount can be adjusted according to the conditions, and the predetermined injection amount can be injected with the ground displacement being minimized.
[0023]
Specifically, a desired pressure value and / or flow value is set in the flow pressure controller 10, and in this state, the actual pressure value and / or flow value is obtained from the pressure gauge 8 and / or flow meter 9. The flow rate is sent to the pressure control device 10. Although the return device 7, that is, the three-way cock 7, is not shown, a reversible motor is included so that the actual pressure value and / or flow rate value approaches the set value and maintains the same value according to the instruction of the flow rate pressure control device 10. Then, the reversible motor is rotated forward or reverse, the shaft is moved up and down to adjust the opening of the three-way cock 7, and the flow rate (return amount) to the return pipe 11 is adjusted.
[0024]
In the present invention, the flow pressure controller 10, the pressure gauge 8 and / or the flow meter 9, and the return device 7 (three-way cock 7) can be integrated and used as the flow pressure controller 10.
[0025]
Thereby, not only the discharge amount and / or discharge pressure of the injection liquid fed from each branch pipe 6 to the injection pipe line 2 is maintained in a desired range, but also a plurality of branch pipes 6, 6... Even if any of these stops the injection, the discharge amount and / or discharge pressure of the remaining branch pipes 6 are also maintained in a desired range.
[0026]
FIG. 2 shows an example in which one flow pressure control device 10 is provided. In this case, the pressure gauges 8 and / or flow meters 9 of the plurality of branch pipes 6 are connected to a single flow rate pressure control device 10, and each return flow rate control device 10 instructs each return device 7. give. Accordingly, since only one flow pressure controller 10 is required, the apparatus is simplified.
[0027]
FIG. 3 shows an injection liquid return device 7a and a pressure gauge on the downstream side of the liquid supply system 13, that is, a conduit on the way from the injection liquid pressurizing unit 1 to the branch pipe 6, in the apparatus of FIG. 8a and / or a flow meter 9a are provided, and the infusate return device 7a and the pressure gauge 8a or the flow meter 9a are connected to the flow pressure control device 10, respectively. In this case, the infusate return device 7a distributes the infusate in the liquid feeding system 13 from the liquid feeding system 13 to the return line 11 based on information from the pressure gauge 8a and / or the flow meter 9a. The hydraulic pressure of 13 is maintained at the desired pressure. Also in this case, the infusion solution return device 7, the pressure gauge 8a and / or the flow meter 9a, and the flow pressure control device 10 can be integrated into the flow pressure control device 10.
[0028]
As a result, the discharge amount and / or discharge pressure of the injection liquid fed from the liquid feeding system 13 to the branch pipe 6 at the stage of the liquid feeding system 13 before the injection liquid is introduced into the branch pipe 6 are set in a desired range. Can hold.
[0029]
In this case, the flow pressure of the liquid feeding system 13 pressurized by the injection pressurizing unit 1 maintains the constant pressure P ₀ instructed by the pressure flow control device 10 by the injection liquid return device 7. P ₀ and the flow path cross section A _i of the three-way cock 7 of each branch pipe 6 are selected so that the differential pressure ΔP _i = P ₀ −P _i with respect to the injection pressure P _i of each branch pipe 6 is sufficiently maintained. Then, the instantaneous discharge amount of each injection pipe line 2 can be maintained by the differential pressure ΔP _i and the flow path cross section A _i .
[0030]
If the injection pressure P _i in the injection process vary the differential pressure △ P _i is changed, it is possible to maintain the instantaneous flow rate q _i of infusion line 2 which corresponds by varying the flow cross section A _i in a predetermined range or differential pressure △ P _i can be minimized displacement of the ground by varying the channel cross-section a _i so as to maintain a predetermined range.
[0031]
Therefore, the discharge amount and / or discharge pressure of the injection liquid fed from each branch pipe 6 to the injection pipe line 2 is more accurately maintained within a desired range, and any of the plurality of branch pipes 6 performs injection. Even if the operation is stopped, the discharge amount and / or discharge pressure of each remaining branch pipe 6 is also maintained in a desired range more accurately.
[0032]
The ground injection solution 5 used in the present invention is arbitrarily selected from the injection solutions shown in the following a) to f). Since all of these injection solutions 5 can set the gelation time to dozens of hours, there is no concern about gelation even if a large amount of injection solution is prepared and placed, and a large amount of injection solution is sent over a long period of time. Since it can be liquid, and after being injected into the ground, it is gelled reliably, and the viscosity is small and the stickiness is low. Therefore, the three-way cock of the return device 7 is not clogged with silica gel. It is extremely excellent. In addition, suspension infusion solutions such as cement and slag are also suitable for the present invention because they have less stickiness and are less likely to clog the three-way cock. In addition, if the apparatus of the present invention is used in a plurality of sets, the main material and the reactants are separately fed through the branch pipe and merged in the injection pipe or reacted after being discharged into the ground, Can be injected.
[0033]
a) An injection liquid mainly composed of a silica solution obtained by removing a part or all of alkali in water glass with an ion exchange resin or an ion exchange membrane.
[0034]
b) An injection solution mainly composed of a non-alkali silica solution obtained by neutralizing the alkali of water glass with an acid.
[0035]
c) An injection liquid mainly composed of colloidal silica obtained by removing alkali from water glass by ion exchange and granulating the obtained silica.
[0036]
d) An injection solution mainly composed of a silica solution obtained by adding water glass and / or colloidal silica to a silica solution obtained by removing alkali from water glass.
[0037]
e) An injection solution mainly composed of a silica solution obtained by mixing water glass, colloidal silica, and a reactant.
[0038]
f) Suspended infusate.
[0039]
【The invention's effect】
As described above, the present invention injects the ground injection liquid into the ground through a plurality of injection pipes installed in the ground, and when the ground is consolidated, an injection liquid pressurizing unit that pressurizes the injection liquid; A plurality of branch pipes that are connected to the injection liquid pressurizing section and send the injection liquid pressurized by the pressurizing section to the plurality of injection pipes, respectively, and injections provided in the plurality of branch pipes, respectively A pressure gauge and / or a flow meter provided in the liquid return device and the branch pipe on the downstream side thereof, and connected to the pressure gauge and / or the flow meter to receive information from them, and connected to the injection liquid return device Then, ground injection is performed using a ground injection device provided with a flow rate pressure control device that gives an instruction to the return device based on these information.
[0040]
For this reason, when injecting the injection solution from the injection solution pressurizing section through the branch pipe and into the ground from the injection pipe line, this injection is performed while giving an instruction for diversion to the injection liquid return device. Can be maintained at the desired pressure.
[0041]
Therefore, while maintaining the discharge amount and / or discharge pressure of the infusion solution sent from each branch pipe to the injection pipe line in a desired range, even if any of the plurality of branch pipes stops the injection, the remaining amount remains. The discharge amount and / or discharge pressure of each branch pipe is maintained in a desired range.
[Brief description of the drawings]
FIG. 1 is a flow sheet of a specific example of a ground injection device according to the present invention.
FIG. 2 is a flow sheet of another specific example of the ground injection device according to the present invention.
FIG. 3 is a flow sheet of still another specific example of the ground injection device according to the present invention.
FIG. 4 is a flow sheet using a plurality of injection pumps as an injection liquid pressurizing unit.
[Explanation of symbols]
A ground injection device 1 injection liquid pressurizing unit 2 injection pipe 3 ground 4 injection liquid tank 5 ground injection liquid 6 branch pipe 7 return device 7a return device 8 pressure gauge 8a pressure gauge 9 flow meter 9a flow meter 10 flow pressure control device 11 Return Line 12 Injection Pump 13 Liquid Supply System 14 Connection Portion

Claims

In a ground injection device that injects ground injection liquid into the ground through a plurality of injection pipes installed in the ground and consolidates the ground, an injection liquid pressurizing unit that pressurizes the injection liquid, and this injection liquid addition A plurality of branch pipes that communicate with the pressure and feed the pressurization liquid pressurized by the pressurizing unit to the plurality of injection pipe lines, respectively, and each of the plurality of branch pipes includes an injection liquid return device and A pressure gauge and / or a flow meter is provided on the downstream side of this, and the injection liquid return device diverts the injection liquid in the branch pipe from the branch pipe based on information from the pressure gauge and / or the flow meter. more that allows the hydraulic pressure in the branch pipe and held at a desired pressure, thereby the discharge amount and / or the discharge pressure of the injected liquid is fed to the injection pipe from the branch pipes held in the desired range At the same time injected Then door from the infusion line , The ground injection apparatus or a plurality of branch pipes Stopping the injection, characterized by simultaneously injecting holds the remaining discharge amount and / or the discharge pressure of the branch pipes in the desired range.

The ground injection device according to claim 1, wherein the injection liquid pressurizing unit includes one or a plurality of injection pumps.

The ground injection device according to claim 1, wherein the injection liquid pressurizing unit includes a compressor.

2. The ground injection device according to claim 1, wherein the injection liquid return device comprises a three-way cock.

The flow rate pressure control device according to claim 1, further comprising a flow rate pressure control device connected to a pressure gauge and / or a flow meter to receive these information, and connected to an infusate return device based on the information. 2. The ground injection device according to claim 1, wherein an instruction is given to the return device, and the return device receives the instruction and diverts the injection solution from the branch pipe so that the injection solution being sent maintains a predetermined pressure. .

6. The ground injection device according to claim 5, wherein the pressure gauge and / or the flow meter, the injection liquid return device, and the flow rate pressure control device are integrated and used as the flow rate pressure control device.

In claim 1, the liquid feeding system from the infusate pressurizing section to the branch pipe is provided with an infusate return device and a flow meter and / or a pressure gauge on the downstream side of the infusate return device. Based on the information from the pressure gauge and / or flow meter, the injection liquid in the liquid supply system is diverted from the liquid supply system, so that the injection liquid in the liquid supply system is maintained at a desired pressure and is supplied to the branch pipe. The ground injection device according to claim 1.

In the ground injection method for injecting the ground injection liquid into the ground through a plurality of injection pipes installed in the ground, and consolidating the ground, an injection liquid pressurizing unit that pressurizes the injection liquid, and this injection liquid addition A plurality of branch pipes communicating with the pressure section and sending the injection liquid pressurized by the pressurization section to the plurality of injection pipes, respectively, and an injection liquid return device provided in each of the plurality of branch pipes; A pressure gauge and / or a flow meter provided in a branch pipe downstream of this, and connected to the pressure gauge and / or flow meter to receive information from them, and connected to an infusion return device, the information When the injecting solution is injected from the injection pressurizing unit into the ground via the branch pipe and the injection conduit, the injection is performed. Injection solution In which the fluid pressure in the branch pipes is maintained at a desired pressure by giving an instruction of the branch flow to the flow device, whereby the discharge amount of the injection liquid sent from each branch pipe to the injection pipe line and Injecting simultaneously from a plurality of injection pipes while maintaining the discharge pressure in a desired range, and even if any of the plurality of branch pipes stops injection, the discharge amount and / or discharge of each remaining branch pipe A ground injection method characterized by simultaneous injection while maintaining the pressure within a desired range.

9. The ground injection method according to claim 8, wherein the pressure gauge and / or the flow meter, the injection liquid return device, and the flow rate pressure control device are integrated and used as the flow rate pressure control device.

9. The ground injecting method according to claim 8, wherein the injection liquid pressurizing unit is composed of one or a plurality of injection pumps.

The ground injection method according to claim 8, wherein the injection liquid pressurizing unit includes a compressor.

9. The ground injection construction method according to claim 8, wherein the injection liquid return device comprises a three-way cock.

In claim 8, the liquid supply system from the injection liquid pressurizing unit to the branch pipe is provided with an injection liquid return device and a flow meter and / or a pressure gauge on the downstream side of the injection liquid return device. Based on the information from the pressure gauge and / or the flow meter, the injection liquid in the liquid supply system is diverted from the liquid supply system, so that the injection liquid in the liquid supply system is held at a desired pressure and sent to the branch pipe. The ground injection construction method according to claim 8.

The ground injection solution according to claim 8,
a) An injection solution mainly composed of a silica solution obtained by removing a part or all of the alkali in the water glass;
b) an injection solution mainly composed of a non-alkaline silica solution obtained by neutralizing the alkali of water glass with an acid;
c) An injection solution mainly composed of colloidal silica,
d) An injection liquid mainly composed of a silica solution obtained by adding water glass and / or colloidal silica to a silica solution obtained by removing alkali from water glass;
e) An injection liquid mainly composed of a silica solution obtained by mixing water glass, colloidal silica, and a reactive agent;
f) Suspended infusate.
The ground injection construction method according to claim 8, which is selected from the group consisting of: