JP3965241B2

JP3965241B2 - Pipe propulsion method with intermediate shaft leading type

Info

Publication number: JP3965241B2
Application number: JP05217698A
Authority: JP
Inventors: 和邦冨田; 幹雄林; 博史橋場; 俊三杉本; 次雄山本; 幸雄石塚; 紘志児島; 実藤森; 克哉野澤
Original assignee: CITY OF NAGOYA; Takenaka Civil Engineering and Construction Co Ltd
Current assignee: CITY OF NAGOYA; Takenaka Civil Engineering and Construction Co Ltd
Priority date: 1998-03-04
Filing date: 1998-03-04
Publication date: 2007-08-29
Anticipated expiration: 2018-03-04
Also published as: JPH11247592A

Description

【０００１】
【発明の属する技術分野】
この発明は、例えば下水道管等を地下に埋設するにあたり、同管を地中内で目標地点に向かって推進させて設置する管推進工法の技術分野に係り、さらに言えば、発進立坑と到達立坑との中間にマンホール等を設ける必要のために用意される中間立坑を管の推進に先行して設け、管は中間立坑を貫通するように推進させる、中間立坑先行型の管推進工法に関する。
【０００２】
【従来の技術】
従来、管推進工法は種々公知、周知である。マンホール等の必要のため一定の管路長さ毎に設けられる中間立坑の構築に関しては、大きくは管の推進（通過）後に掘削して設ける方法と、中間立坑を先行して設ける方法とに大別される。更に後者の方法は、
▲１▼構築した中間立坑において、先端推進装置を通過させた後、防護管による密閉を行わず、そのままの状態で放置する方法。
▲２▼構築した中間立坑において、先端推進装置を通過させた後、防護管による密閉の代わりに、直ちに同立坑を適当な埋め戻し材で必要高さまで埋め戻し、その中で管を推進、通過させ、その後再び立坑を復元する方法。
▲３▼構築した中間立坑において、先端推進装置を通過させた後、防護管による密閉の代わりに、直ちに同立坑を泥水等の液体で満水にし、その中で管を推進、通過させ、その後再び立坑を復元する方法。
に大別される。
【０００３】
【本発明が解決しようとする課題】
Ｉ）管の推進（通過）後に掘削して中間立坑を設ける方法についての問題点
中間立坑の掘削に際しては埋設管が障害物となり、施工される山留め用ライナープレートの設置は、垂直な立坑と水平な埋設管との交差部分（交わりの稜線）を幾何学的に解析して成形加工した複数のプレート片の集合として組み立てることになり、プレートの加工及び組み立てが大変面倒で手間がかかり、またライナープレートを使った立坑の構造上、大きな欠損部位は立坑強度を弱くする。立坑の掘削に際しては管推進工の前に予め地盤改良を行うのが一般的であるが、先端推進装置が立坑下を通過した後、地山は乱れて水みちが付く。そのため補足の地盤改良が行われるが、埋設管の存在によってその近隣部位乃至下部の地盤改良が不十分となる場合がある。その結果、地下水位が高い地盤では地山の崩壊、流出事故を起こして掘削作業の進行が大幅に遅れ、工期が長引いたり、周辺に陥没事故を起こす恐れがあり、工事が難しい。そして、埋設管の近隣部位及び下部の掘削は手掘りで行うほかなく、この意味でも工事が面倒で長引く。
【０００４】
埋設管の外径（２３５０mm）に比べて２カ所の中間立坑の口径は３７００〜４５００mm程度と小さいため、作業スペースを十分にとれず、上記の問題点が重複するという困難性もある。
II）中間立坑を先行して設け、管を推進、通過させた後そのままの状態で放置する方法の問題点
長期間の連続的な管の通過により、坑口に付けたエントランスパッキンが摩耗したり、転石等の異物がエントランスパッキンと管との間に挟まったりしてエントランスパッキンを破損する危険性がある。この場合、地下水位の高い地盤では土砂と地下水が隙間から流出し、それが地山の崩壊を導き、周辺地盤の沈下や陥没を起こす恐れが出てくる。
III）中間立坑を先行して設けるが、管を推進、通過させるまで適切な埋め戻し材で埋め戻す方法の問題点
この方法は、上記II）の問題点を解決するための折衷案的なものであり、長所、短所が相半ばするが、一旦掘削し構築した中間立坑を、管の推進、通過まで埋め戻すので、工程の重複、２度手間の欠点は図り知れず大きい。また、埋め戻しが完了するまで管推進工を停止する必要があり、再掘進時に大きな推力を必要とする。さらに立坑内に切梁等が存在する場合、埋め戻しが困難である。
IV）中間立坑を先行して設けるが、管を推進、通過させるまで泥水等の液体で満水にする方法の問題点
この方法は、上記II）III）の問題点を解決するためのものであり、坑口の取り付け及び管の通過後、直ちに泥水等の液体で立坑内を満水として再掘進することができるが、液体内において作用する浮力が全て露出した管にかかるため、十分な浮力対策を行わないと管の蛇行やひねりを招いたり、予期せぬ過大な偏圧によって管を破損する可能性がある。
【０００５】
従って、本発明の目的は、中間立坑を先行して構築する長所を温存しつつ、管の推進、通過を安全に効率よく短工期に行えるように改良した中間立坑先行型の管推進工事を提供することである。
【０００６】
【課題を解決するための手段】
上記の課題を解決するための手段として、請求項１記載の発明に係る中間立坑先行型の管推進工法は、発進立坑に設置した元押し装置と先端推進装置との協同作用により管体を到達立坑に向かって推進させる管推進工法において、
発進立坑と到達立坑との中間位置に、管体を通過させる中間立坑を、先端推進装置の到達以前に構築すること、
先端推進装置が中間立坑のライナーへ到達した段階で、同先端推進装置の位置を確認して立坑内基線の測量を行い、前記の測量結果に基づいて到達坑口と発進坑口を中間立坑内に設置すること、
中間立坑の底部に架台を設置し、その上に前記到達坑口と発進坑口を連絡する防護管の下半部を取り付けること、
前記到達坑口の内周に沿ってライナーに先端推進装置を通過させる開口を設ける鏡切りを行い、先端推進装置を中間立坑内へ進ませること、
発進立坑の内周に沿ってライナーに先端推進装置を通過させる開口を設ける鏡切りを行い、先端推進装置を中間立坑の外まで進ませること、
前記防護管の下半部の上に上半部を取付け、密閉された防護管の中に充填材を注入し、その後管体の推進を続行すること、
をぞれぞれ特徴とする。所謂坑口方式である。
【０００７】
請求項２記載の発明は、請求項１に記載した中間立坑先行型の管推進工法において、到達坑口と発進坑口に補強コンクリートを打設し、また、先端推進装置を到達坑口に通過させる以前、及び発進坑口へ前進させる以前に各坑口にエントランスパッキンを取付けておき、そこを先端推進装置を通過させてから防護管で密閉し、速硬性または通常硬化の充填材で空隙を充填することを特徴とする。
【０００８】
請求項３記載の発明は、請求項１に記載した中間立坑先行型の管推進工法において、到達坑口と発進坑口には、先端推進装置を到達坑口に通過させる以前、及び発進坑口へ前進させる以前に各坑口にエントランスパッキンを取付けておき、そこを先端推進装置を通過させてから防護管で密閉し、速硬性または通常硬化の充填材で空隙を充填することを特徴とする。
【０００９】
請求項４記載の発明に係る中間立坑先行型の管推進工法は、発進立坑に設置した元押し装置と先端推進装置との協同作用により管体を到達立坑に向かって推進させる管推進工法において、
発進立坑と到達立坑との中間位置に、管体を通過させる中間立坑を、先端推進装置の到達以前に構築すると共に以下の準備を行うこと、
先端推進装置の通過予定位置に基づいて中間立坑内基線の測量を行い、前記の測量結果に基づいて中間立坑の底部に架台を設置し、その上に防護管の下半部と管両端部を取り付けること、
到達側と発進側の管端部の内周に沿ってライナーに先端推進装置を通過させる開口を設ける鏡切りを行い、防護管の上半部を取付け、かくして密閉された防護管の内部へ充填材を注入すること、
以上の準備を完了した後に、先端推進装置を中間立坑にまで到達させ、更に防護管の中を通過させて管体の推進を継続すること、
をぞれぞれ特徴とする。所謂貫通方式である。
【００１０】
請求項５記載の発明は、請求項４に記載した中間立坑先行型の管推進工法において、ライナーの鏡切りの直後に管端部の坑内側端面を密閉し、速硬性の充填材を管端部の中に充填し、同充填材が硬化した後に前記密閉を解くことを特徴とする。
請求項６記載の発明は、請求項４に記載した中間立坑先行型の管推進工法において、防護管の内部への充填材の注入は、先ず防護管の下半部に速硬性の充填材を充填し、続いて防護管の残る空隙部に通常硬化の充填材を密に充填することを特徴とする。
【００１１】
請求項７記載の発明は、請求項４に記載した中間立坑先行型の管推進工法において、防護管の内部への充填材の注入は、防護管の下半部に通常硬化の充填材を充填し、続いて防護管の残る空隙部にも通常硬化の充填材を密に充填することを特徴とする、。
【００１２】
【発明の実施の形態及び実施例】
請求項１記載の発明に係る中間立坑先行型の管推進工法は、図示を省略した発進立坑に設置された元押し装置と先端推進装置との協同作用により管体を到達立坑に向かって推進させる管推進工法において、所謂坑口方式として好適に実施される。なお、図示を省略した発進立坑の反力壁裏側の地山は、先端推進装置２及び管体の推進力によって地山が挙動しないように、場合によっては薬液補強注入を行う。これは、管内測量の精度を確保する意味もある。
【００１３】
その枢要な工程図を図１〜図６に示した。図示を省略した発進立坑と到達立坑との中間位置に、管体１を通過させる中間立坑３を、先端推進装置２の到達以前に構築することが第１の条件である。中間立坑３の構築は、仮設計画段階で防護管等の部材が立坑内に搬入できるように、覆工計画や既設管の吊り防護計画等を行う。施工では掘削地盤について先ず薬液注入等による地盤改良を行う。この時、特に先端推進装置２の到達と発進坑口付近には地山補強のために薬液補足注入を行う。その後公知の掘削工法により、山留めのライナープレート４を施工しつつ地盤を中堀りする方式で所要の深さ（例えば地下８．５ｍ位）まで掘削し構築する。今回坑口方式を採用した中間立坑３の口径は、最終的なマンホールの仕上がりを考慮しておよそ４．５ｍ程度である。掘削底面には底盤コンクリート５を打設する。また、ライナープレート４の外周地盤には余掘りした空隙を埋めるために、ライナープレート設置後逐次裏込め注入を行う。
【００１４】
発進立坑から発進させ推進を進めて来た先端推進装置２は、前記のように中間立坑３の構築が完成した後に、当該中間立坑３のライナー４へ到達させる。ここで先端推進装置２が中間立坑３のライナー４へ到達するとは、先端推進装置２の先端をライナー４へ押し当て坑内側へ若干膨らます程度に突き当たった状態を意味する。この段階で、中間立坑３の内側から、先端推進装置２の先端が当たって膨らんだ部分のライナー４を確認作業に必要な範囲まで切り取り、目視により同先端推進装置２の推進位置を確認して立坑内基線の測量を行う。そして、前記の測量結果に基づいて定めた位置に到達坑口６と発進坑口７を中間立坑３内に設置し、補強コンクリート８を打設して強固に固定する。
【００１５】
到達坑口６と発進坑口７、補強コンクリート８の詳細な構造は、図７〜図１１に実施例を示したとおりである。到達坑口６と発進坑口７は共に鋼板の組み立て品であり、先端推進装置２が通過する線上に同先端推進装置２が通過し得る口径（例えば管体外径が２３５０mmに対して約１００mmの隙間を持つ口径）の円筒体６ａ又は７ａの外端がライナープレート４と溶接で密接に接合される。該円筒体６ａ又は７ａの内端部にはリング状のフランジ６ｂ又は７ｂが直角外向きに取付けられ、前記円筒体の外周とフランジ及びライナープレート４とに囲まれた隅部に補強コンクリート８が打設され、もって各坑口の取付け状態を大重量の先端推進装置２及び管体１の通過に耐える構成とされている。もっとも、坑口及び防護管の支持耐力に不安があるときは、同防護管の下半部に補強コンクリートを打設することも行う。
【００１６】
前記到達坑口６のフランジ６ｂには、先端推進装置２及び管体１の通過時に土砂、地下水の流出を可及的に防止する手段としてドーナツ形状のゴム製エントランスパッキン９を取り付ける。エントランスパッキン９は管体１の外径よりも少し小さい（実施例では半径にして２００mm程度小さい）内径のドーナツ形状のものであり、これは図８のように当該パッキン９の坑内面側に、且つ図９のように放射方向に多数配置する平プレート形状のパッキン押さえ１０と共にボルト１１で外径寄り位置を固定される。また、各パッキン押さえ１０の内径寄り位置に設けられたパイプ１０ａにワイヤー１２を一連に通して円形状に配置しておく。従って、この到達坑口６を先端推進装置２及び管体１が通過するときは、前記エントランスパッキン９はパッキン押さえ１０と共に図８に点線で示したように坑内側へ先細のラッパ状に突き出すように変形する。その際前記のワイヤー１２を引き絞ることによって土砂、地下水の流出を防ぐに足る密閉圧力をエントランスパッキン９へ付与する。
【００１７】
また、発進坑口７のフランジ７ｂの坑内面側にも、先端推進装置２及び管体１の通過時に土砂、地下水の流出を可及的に防止する手段として、ドーナツ形状のゴム製エントランスパッキン９を取り付ける。このエントランスパッキン９も管体１の外径よりも少し小さい内径のドーナツ形状であり、これは図１０のように当該パッキン９の坑内面側に、且つ図１１のように放射方向に多数配置する平プレート形状のパッキン押さえ１３と共にボルト１１で外径寄り位置を固定される。
【００１８】
従って、この発進坑口７を先端推進装置２及び管体１が通過するときは、前記エントランスパッキン９はパッキン押さえ１３と共に図１０に点線で示したように坑口の中へ引っ張り込まれて先細のラッパ状に変形する。その背後をパッキン押さえ１３が支えて土砂、地下水の流出を防ぐに足る密閉圧力をエントランスパッキン９に生じさせる。
【００１９】
上記のようにして坑口の準備が出来た後に、当該中間立坑３の底部、即ち底盤コンクリート５の上に架台１４を設置し、その上に前記到達坑口６と発進坑口７を連絡する防護管を半割りにした下半部１５を取り付ける。その詳細は図１０に上半部１６の取付け態様を点線で図示し、図１２に下半部１５と上半部１６の関係を示したように行う。即ち、下半部１５と坑口とは、同坑口のフランジ６ｂ又は７ｂの坑内面側に防護管取付け用の袋ナット１７を同心配置しておいて、フランジ６ｂ，７ｂに防護管の下半部１５のフランジを当接させ、両者はフランジ同士をボルト止めする。この時、下半部１５の底部のボルト止めの作業を容易にするため、予め下半部１５には作業口を適当に準備しておく。なお、下半部１５の取り付けが完了したら、作業口及び隙間はロール加工した鉄板等を溶接して覆い、充填材が漏出しない構造とする。
【００２０】
次に、前記到達坑口６の内周に沿ってライナー４に先端推進装置２を通過させる口径の開口を設ける鏡切りを行う。鏡切りはライナー４を溶断する方法が好適に実施される。この場合、ライナープレート４の外周地盤については、当初に説明したように予め地盤改良を施しておくので、鏡の崩壊、地山の崩壊は一応防止されている。しかし、なお不測の崩壊事故を防ぐため、前記下半部１５の内周に予め防護壁１８を設けておき、最悪の場合でも地山の崩壊は４５°程度の安息角で安定化させることを図る。そして、鏡切りの後は速やかに図４のように先端推進装置２を推進させ到達坑口６の中へ進入させて坑口を塞ぎ、土砂及び地下水の流入を可及的に防ぐ。その後に前記防護壁１８は撤去する。従って、前記防護壁１８は撤去を容易ならしめるため、ボルト止めとしておく。
【００２１】
次に、発進立坑７の内周に沿ってライナー４に先端推進装置２を通過させる開口を設ける鏡切りを行う。その後速やかに先端推進装置２を発進立坑７へ進入させ、更に中間立坑３（ライナープレート４）の外へ図５のように突き出る状態にまで進ませ、もって発進立坑７の坑口を塞ぎ、土砂及び地下水の流入を可及的に防ぐ。
【００２２】
しかる後に、図５及び図６のように防護管の前記下半部１５の上に上半部１６を載せ、両坑口側は袋ナットでのボルト止めをし、下半部１５と上半部１６はフランジ同士のボルト止めにて防護管を完成する。このように本工法は一度先端推進装置２を中間立坑３内に露出させるため、もし工事上の障害、事故が生じたときは即時の対応措置を実行することが可能であり、安全、確実な方法である。
【００２３】
前記の工程で完成された防護管は、充填材の漏出を防止するために、外側から止水モルタル等で間隙を密閉してから、充填材を密実に注入して防護管の中を地山と同等な条件に保つ。使用する充填材は、例えばセメントとベントナイトを水で混合した通常の硬化速度のものであり、場合によっては水ガラスとセメントを混合した速硬性の充填材を使用する。その後管体１の推進を再開し続行する。
【００２４】
本工法によれば、中間立坑３に関係する地山の崩壊、陥没事故、周辺民家の損傷といったトラブルは皆無で実施され、また中間立坑を管推進の前に築造できたことは工期及び工程面での意義も大きかった。
次に、請求項３に記載した発明に係る中間立坑先行型の管推進工法も、やはり発進立坑に設置した元押し装置と先端推進装置との協同作用により管体を到達立坑に向かって推進させる管推進工法において、所謂貫通方式として好適に実施される。勿論、発進立坑と到達立坑との中間位置に、管体を通過させる中間立坑３を、先端推進装置２の到達以前に完全に構築することが条件であるが、本工法の場合は、先端推進装置２が到達される前に、中間立坑３の構築と防護管の設置が完成していることが特徴である。従って、上記の大実施例のように、中間立坑３へ先端推進装置２を到達させたまま、準備が整うまで待機させる方法に比べて、時間の無駄がない。本工法の場合、先端推進装置２の到達以前に次の準備を行う。
【００２５】
本工法を実施する枢要な工程を図１３〜図１８に示した。今回貫通方式を採用した中間立坑３の口径は、最終的なマンホールの仕上がりを考慮しておよそ３．７ｍ程度である。中間立坑３が完成すると、測量しながら方向制御をして推進してくる先端推進装置２の通過予定位置に基づいて中間立坑内基線の測量を行い、前記の測量結果に基づいて中間立坑の底部、即ち底盤コンクリート５の上に架台１４を設置し、その上に防護管の下半部２０ａと管両端部２０ｂを取り付ける（図１３，図１４）。つまり、推進してくる先端推進装置２の通過予定位置に基づいて予め防護管を用意する工法であるから、その前提として、先端推進装置２の推進制御に関して、高度に正確な、信頼性の高い測量及び方向制御の技術が確立されていることが要求される。
【００２６】
その後到達側と発進側それぞれの管端部２０ｂの内周に沿って、ライナー４に先端推進装置２を通過させる開口を設ける鏡切りを行う。鏡切りはライナー４を溶断する方法が好適に実施され、溶断に際しては、管端部２０ｂとライナー４との接合部からライナー端片を若干（実施例では３０ｍｍぐらい）残すように溶断するのが良い。本工法の場合も、ライナープレート４の外周地盤については、当初に予め地盤改良をし、更に到達と発進部分には補足注入をしており、また未だ先端推進装置２が到達していないので地山が乱されていない利点もあり、鏡の崩壊、地山の崩壊は一応防止されている。しかし、なお不測の崩壊事故を防ぐため、管端部２０ｂの坑内側端面の下半部位に予め防護壁を設けておき、最悪の場合でも地山の崩壊は前記の防護壁で抑制して４５°程度の安息角で安定化させることを図ることも良い。そして、前記鏡切りを終えると速やかに管端部２０ｂの坑内側端面を防護壁により全面を密閉し、速硬性の充填材を管端部２０ｂの中に充填し、地山の崩壊、地下水の流出を可及的に未然に防止する。前記充填材が十分硬化した後に、前記防護壁を撤去して密閉を解く。前記速硬性の充填材としては、瞬時に硬化する水ガラスとセメント系の充填材が好適に使用される。
【００２７】
その後に、防護管の上半部を取り付けて防護管２０の組み立てを完成させる。防護管２０の構造の詳細は図１８に示した通りで、全て鋼板の組み立て品である。この防護管２０は、先端推進装置２及び管体１の通過時にそれらの重量に耐える強度に設計、製作されている。前記の工程で完成された防護管は、充填材の漏出を防止するために、防護管の内外側から止水モルタル等で間隙を密閉してから、充填材を密実に注入する（図１５）。ここで充填材の注入方法としては、先ず防護管の下半部２０ａの範囲に速硬性の充填材を充填し、防護管と両側端部の溶接箇所等からの充填材の漏出を防ぐ。続いて防護管の残る空隙部（上半部）に通常硬化の充填材（例えば既述したセメント、ベントナイト系充填材）を密に充填する。その結果、防護管２０の内部は、地山と同等な条件になって地山の崩壊、地下水の流出等の事故は未然に防止される。さらに、万一の不測の事故を未然に防止するために、管端部２０ｂの外周に図１８のように強化コンクリート８を打設したり、防護管２０の外周の下部に図１６及び図１９のように補強コンクリート２１を打設して、防護管の耐力の向上を図ることも好ましい。
【００２８】
以上の準備が全て完了した後に、先端推進装置を中間立坑にまで到達させ、そのまま停止することなく、図１７のように防護管２０の中を通過させて、次の中間立坑又は到達立坑に推進を継続する事になる。
本工法においても、中間立坑３に関係する地山の崩壊、陥没事故、周辺民家の損傷といったトラブルは皆無で実施され、しかも先端推進装置が到達する前に防護管設置の準備が完了することから、坑口方式よりも工期を短縮することができた。これら坑口方式と貫通方式の２つの工法により、３５０ｍの管推進と２カ所の中間立坑の構築を従来工法で行った場合に比較して、約１カ月の工期短縮（３カ月が約２カ月）を行うことができた。
【００２９】
本発明は以下のことにも適用又は応用できる。
▲１▼中間立坑に限らず、発進、到達立坑でも適用できる。
▲２▼鏡切り部位はライナープレートばかりでは無く、鋼矢板等でも良いため、中間立坑等の山留めを鋼矢板方式で行うことができる。
▲３▼推進工事に限らずシールド工事でも適用できる。
▲４▼到達側は坑口方式のエントランスパッキン付きの坑口を取り付け、発進側は貫通方式の防護管の片端部で代用する混合方式もできる。
▲５▼防護管は必ずしも円筒型でなくても良い。
【００３０】
【本発明が奏する効果】
本発明によれば、中間立坑を先行して設ける管推進工法であるから、その利点を享受することは勿論のこと、中間立坑先行型の数々の問題点を統べて解決して、施工の容易さと、効率の良さ、陥没事故等を決して起こさない安全性が達成されると共に、工期の大幅な短縮を達成する等々の優れた効果を奏するのである。
【図面の簡単な説明】
【図１】本発明の坑口方式の管推進工法の第１の工程を示した断面図である。
【図２】管推進工法の次の工程を示した断面図である。
【図３】管推進工法の工程を示した断面図である。
【図４】管推進工法の工程を示した断面図である。
【図５】管推進工法の工程を示した断面図である。
【図６】管推進工法の工程を示した断面図である。
【図７】防護管の設置状態を示した平面図である。
【図８】到達坑口のエントランスパッキンの部分を示した断面図である。
【図９】到達坑口のエントランスパッキンの部分を示した正面図である。
【図１０】発進坑口のエントランスパッキンの部分を示した断面図である。
【図１１】到達坑口のエントランスパッキンの部分を示した正面図である。
【図１２】防護管の組み立て態様を示した正面図である。
【図１３】本発明の貫通方式の管推進工法の第１の工程を示した断面図である。
【図１４】管推進工法の次の工程を示した断面図である。
【図１５】管推進工法の工程を示した断面図である。
【図１６】管推進工法の工程を示した断面図である。
【図１７】管推進工法の工程を示した断面図である。
【図１８】防護管の設置状態を示した平面図である。
【図１９】図１７の１９ー１９線矢視図である。
【符号の説明】
１管体
２先端推進装置
３中間立坑
４ライナー
５底盤コンクリート
６到達立坑
７発進立坑
１４架台
１５防護管の下半部
１６防護管の上半部[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a technical field of a pipe propulsion method in which, for example, a sewer pipe or the like is buried underground and propelled toward a target point in the ground, and more specifically, a start shaft and a reach shaft The intermediate shaft prepared for the necessity of providing a manhole etc. in the middle is provided prior to the propulsion of the pipe, and the pipe is propelled so as to penetrate the intermediate shaft.
[0002]
[Prior art]
Conventionally, various tube propulsion methods are known and well known. Regarding the construction of intermediate shafts that are provided at fixed pipe lengths due to the need for manholes, etc., there are two major methods: the method of excavating after propelling (passing) the tube and the method of providing the intermediate shaft in advance. Separated. Furthermore, the latter method is
(1) In the constructed intermediate shaft, after passing through the tip propulsion device, it is left as it is without being sealed with a protective pipe.
(2) After passing the advanced propulsion device in the constructed intermediate shaft, immediately backfill the shaft to the required height with a suitable backfill material instead of sealing with a protective tube, and propel and pass the tube in it. And then restore the shaft again.
(3) In the constructed intermediate shaft, after passing through the tip propulsion device, instead of sealing with a protective pipe, the shaft is immediately filled with a liquid such as muddy water, in which the pipe is propelled and passed, and then again How to restore a shaft.
It is divided roughly into.
[0003]
[Problems to be solved by the present invention]
I) Problems with the method of excavating the pipe after passing (passing) and providing the intermediate shaft The buried pipe becomes an obstacle when excavating the intermediate shaft, As a result, it will be assembled as a set of a plurality of plate pieces formed by geometrically analyzing the intersecting part (crossing ridgeline) with a buried pipe, and processing and assembly of the plate will be very cumbersome and time-consuming. Due to the structure of the shaft using the plate, the large defect part weakens the shaft strength. When excavating a shaft, it is common to improve the ground beforehand before the pipe propulsion work. However, after the tip propulsion device passes under the shaft, the ground is disturbed and has a water channel. Therefore, supplementary ground improvement is performed, but the presence of the buried pipe may result in insufficient ground improvement in the vicinity or the lower part thereof. As a result, in the ground where the groundwater level is high, collapse and runoff accidents occur in the ground, and the progress of the excavation work is greatly delayed, which may prolong the construction period and cause a collapse accident in the surrounding area, making construction difficult. And the excavation of the neighboring part and the lower part of the buried pipe must be done by hand, and in this sense, the construction is troublesome and protracted.
[0004]
Since the diameter of the two intermediate shafts is as small as about 3700-4500 mm compared to the outer diameter (2350 mm) of the buried pipe, there is a difficulty that the work space cannot be taken sufficiently and the above problems are duplicated.
II) Problems of the method of leaving an intermediate shaft in advance and propelling and passing the pipe and leaving it as it is, the entrance packing attached to the wellhead wears out due to the continuous passage of the pipe for a long time, There is a risk that foreign matter such as rolling stones may get caught between the entrance packing and the pipe and damage the entrance packing. In this case, in the ground where the groundwater level is high, earth and sand and groundwater flow out from the gap, which leads to the collapse of the natural ground, and the surrounding ground may sink or sink.
III) The problem of the method of backfilling with an appropriate backfilling material until the pipe is propelled and passed through in advance of the intermediate shaft, but this method is a compromise for solving the problem of II) above However, since the intermediate shaft once excavated and constructed is backfilled until the pipe is propelled and passed, the duplication of processes and the two-time troubles are inevitable. Moreover, it is necessary to stop the pipe propulsion until the backfilling is completed, and a large thrust is required at the time of re-digging. Furthermore, when there are cut beams in the shaft, it is difficult to backfill.
IV) Establishing an intermediate shaft in advance, but the problem with the method of filling the pipe with muddy water or other liquid until the pipe is propelled and passed through is to solve the problem of II) III) above. After installation of the wellhead and passage of the pipe, it is possible to immediately re-excavate the shaft with a liquid such as muddy water, but all buoyancy acting in the liquid is applied to the exposed pipe, so sufficient buoyancy measures are taken Otherwise, the tube may meander or twist, or the tube may be damaged by unexpected excessive bias.
[0005]
Therefore, the object of the present invention is to provide pipe advancement work of the intermediate shaft leading type improved so that the advancement and passage of the pipe can be performed safely and efficiently in a short construction period while preserving the advantages of constructing the intermediate shaft in advance. It is to be.
[0006]
[Means for Solving the Problems]
As means for solving the above-mentioned problem, the intermediate shaft leading type pipe propulsion method according to the invention described in claim 1 reaches the pipe body by the cooperative action of the main pushing device and the tip propulsion device installed in the starting shaft. In the pipe propulsion method propelled toward the shaft,
Build an intermediate shaft that allows the pipe to pass through the intermediate position between the starting shaft and the reaching shaft before the tip propulsion device arrives,
When the tip propulsion device reaches the liner of the intermediate shaft, check the position of the tip propulsion device and measure the baseline in the shaft, and based on the above survey results, install the arrival shaft and the starting shaft in the intermediate shaft To do,
A base is installed at the bottom of the intermediate shaft, and the lower half of the protective pipe connecting the arrival well and the start well is installed on it;
Performing a mirror cutting to provide an opening that allows the tip propulsion device to pass through the liner along the inner circumference of the arrival shaft, and advance the tip propulsion device into the intermediate shaft,
Mirror cutting to provide an opening that allows the tip propulsion device to pass through the liner along the inner periphery of the starting shaft, and advance the tip propulsion device to the outside of the intermediate shaft,
Mounting the upper half on the lower half of the protective tube, injecting filler into the sealed protective tube, and then continuing to propel the tube;
Each has a feature. This is the so-called wellhead method.
[0007]
The invention according to claim 2 is the intermediate shaft leading type pipe propulsion method according to claim 1, in which reinforced concrete is placed in the reaching wellhead and the starting wellhead, and before the tip propulsion device is passed through the reaching wellhead, Before moving forward to the starting pit, an entrance packing is attached to each pit, and after passing through the tip propulsion device, it is sealed with a protective tube and filled with voids with a fast-curing or normal-curing filler. And
[0008]
The invention described in claim 3 is the intermediate shaft leading type pipe propulsion method according to claim 1, wherein the reaching wellhead and the starting well are before the tip propulsion device is passed through the reaching wellhead and before being advanced to the starting wellhead. In addition, an entrance packing is attached to each wellhead, and after passing through the tip propulsion device, it is sealed with a protective tube, and a space is filled with a fast-curing or normal-curing filler.
[0009]
The pipe propulsion method of the intermediate shaft leading type according to the invention of claim 4 is a pipe propulsion method for propelling the pipe body toward the reaching shaft by the cooperative action of the main pushing device and the tip propelling device installed in the starting shaft.
Before the arrival of the tip propulsion device, construct the intermediate shaft that allows the pipe to pass through the intermediate position between the starting shaft and the reaching shaft, and make the following preparations:
Based on the planned passage position of the tip propulsion device, survey the baseline in the intermediate shaft, install a pedestal at the bottom of the intermediate shaft based on the above survey results, and place the lower half of the protective tube and both ends of the tube on it. Installing,
Mirror cut to provide an opening for the tip propulsion device to pass through the liner along the inner circumference of the tube end on the arrival side and the start side, and attach the upper half of the protection tube, thus filling the inside of the sealed protection tube Injecting material,
After completing the above preparation, the tip propulsion device reaches the intermediate shaft, and further passes through the protective pipe to continue the propulsion of the pipe body.
Each has a feature. This is a so-called penetration method.
[0010]
According to a fifth aspect of the present invention, in the intermediate shaft leading type pipe propulsion method described in the fourth aspect, immediately after the mirror cutting of the liner, the inner end face of the pipe end is sealed, and a fast-hardening filler is used as the pipe end. It is characterized in that the sealing is released after filling in the part and the filler is cured.
According to a sixth aspect of the present invention, in the pipe propulsion method of the intermediate shaft preceding type described in the fourth aspect, the injection of the filler into the inside of the protective pipe is performed by first applying a fast-hardening filler in the lower half of the protective pipe. It is characterized in that it is filled and subsequently filled with a normally hardened filler in the remaining space of the protective tube.
[0011]
The invention according to claim 7 is the intermediate shaft leading type pipe propulsion method according to claim 4, wherein the filler is injected into the inside of the protective pipe by filling the lower half of the protective pipe with a normally hardened filler. Then, a normal hardening filler is densely filled into the remaining space of the protective tube.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
According to the first aspect of the pipe propulsion method of the intermediate shaft according to the first aspect of the invention, the pipe body is propelled toward the reaching shaft by the cooperative action of the main pushing device and the tip propulsion device installed in the start shaft not shown. In the pipe propulsion method, it is suitably implemented as a so-called wellhead method. It should be noted that the natural ground behind the reaction wall of the start shaft not shown is subjected to chemical solution reinforcement in some cases so that the natural ground does not move due to the propulsive force of the tip propulsion device 2 and the pipe body. This also has the meaning of ensuring the accuracy of in-pipe surveying.
[0013]
The important process diagrams are shown in FIGS. The first condition is to construct an intermediate shaft 3 through which the pipe body 1 is passed before reaching the tip propulsion device 2 at an intermediate position between the starting shaft and the reaching shaft, not shown. The construction of the intermediate shaft 3 is performed such as a lining plan and a suspension protection plan for existing pipes so that members such as a protection pipe can be carried into the shaft at the temporary design stage. In construction, the ground is first improved by injecting chemicals into the excavated ground. At this time, especially, the chemical solution supplement injection is performed for the reinforcement of the natural ground near the arrival of the tip propulsion device 2 and the vicinity of the starting pit. After that, a known excavation method is used to excavate to a required depth (for example, about 8.5 m below ground) by constructing the liner plate 4 with a mountain and digging the ground. The diameter of the intermediate shaft 3 adopting the wellhead method this time is about 4.5 m in consideration of the final manhole finish. Bottom concrete 5 is placed on the bottom of excavation. Further, in order to fill an excessively dug void in the outer peripheral ground of the liner plate 4, backfilling is sequentially performed after the liner plate is installed.
[0014]
The tip propulsion device 2 that has started from the starting shaft and advanced the propulsion is made to reach the liner 4 of the intermediate shaft 3 after the construction of the intermediate shaft 3 is completed as described above. Here, the fact that the tip propulsion device 2 reaches the liner 4 of the intermediate shaft 3 means a state in which the tip of the tip propulsion device 2 is pressed against the liner 4 and slightly swells to the inside of the pit. At this stage, from the inner side of the intermediate shaft 3, the liner 4 at the portion where the tip of the tip propulsion device 2 hits and swells is cut out to a necessary range for the confirmation work, and the propulsion position of the tip propulsion device 2 is visually confirmed. Survey the vertical shaft baseline. Then, the arrival shaft 6 and the start shaft 7 are installed in the intermediate shaft 3 at the position determined based on the survey result, and the reinforced concrete 8 is placed and firmly fixed.
[0015]
Detailed structures of the arrival wellhead 6, the start well 7, and the reinforced concrete 8 are as shown in the examples in FIGS. The arrival well 6 and the start well 7 are both steel plate assemblies, and the diameter that the tip propulsion device 2 can pass on the line through which the tip propulsion device 2 passes (for example, a gap of about 100 mm with respect to the outer diameter of the tube body of 2350 mm). The outer end of the cylindrical body 6a or 7a having a diameter is closely joined to the liner plate 4 by welding. A ring-shaped flange 6b or 7b is attached to the inner end of the cylindrical body 6a or 7a so as to be perpendicularly directed outward, and a reinforced concrete 8 is provided at the corner surrounded by the outer periphery of the cylindrical body and the flange and liner plate 4. Therefore, the mounting state of each wellhead is configured to withstand the passage of the heavy-weight tip propulsion device 2 and the pipe body 1. However, if there is concern about the bearing strength of the wellhead and protective pipe, reinforced concrete is also placed in the lower half of the protective pipe.
[0016]
A donut-shaped rubber entrance packing 9 is attached to the flange 6 b of the arrival well 6 as a means for preventing as much as possible the outflow of earth and sand and groundwater when passing through the tip propulsion device 2 and the pipe body 1. The entrance packing 9 has a donut shape with an inner diameter that is slightly smaller than the outer diameter of the tube body 1 (in the embodiment, about 200 mm in radius), and this is on the inner surface side of the packing 9 as shown in FIG. Further, as shown in FIG. 9, the position near the outer diameter is fixed with bolts 11 together with the flat plate-shaped packing pressers 10 arranged in the radial direction. Further, the wire 12 is passed through a series of pipes 10a provided near the inner diameter of each packing retainer 10 and arranged in a circular shape. Therefore, when the tip propulsion device 2 and the pipe body 1 pass through the reaching wellhead 6, the entrance packing 9 and the packing retainer 10 protrude in a tapered trumpet shape toward the inside of the well as shown by a dotted line in FIG. Deform. At that time, the wire 12 is drawn to apply a sealing pressure sufficient to prevent outflow of earth and sand and groundwater to the entrance packing 9.
[0017]
A donut-shaped rubber entrance packing 9 is also provided on the inner surface of the flange 7b of the start pit 7 as a means for preventing as much as possible the outflow of earth and sand and groundwater when passing through the tip propulsion device 2 and the pipe body 1. Install. The entrance packing 9 also has a donut shape having an inner diameter slightly smaller than the outer diameter of the tube body 1, and a large number of them are arranged on the inner surface side of the packing 9 as shown in FIG. 10 and in the radial direction as shown in FIG. The position close to the outer diameter is fixed by the bolt 11 together with the flat plate-shaped packing presser 13.
[0018]
Therefore, when the tip propulsion device 2 and the pipe body 1 pass through the starting pit 7, the entrance packing 9 together with the packing retainer 13 is pulled into the pit as shown by a dotted line in FIG. It deforms into a shape. The packing presser 13 supports the back thereof, and generates a sealing pressure at the entrance packing 9 sufficient to prevent outflow of earth and sand and groundwater.
[0019]
After the wellhead is prepared as described above, a base 14 is installed on the bottom of the intermediate shaft 3, that is, on the bottom concrete 5, and a protective pipe for connecting the arrival well 6 and the start well 7 is provided thereon. Attach the lower half 15 which is divided in half. The details are as shown in FIG. 10 where the upper half 16 is attached with dotted lines, and the relationship between the lower half 15 and the upper half 16 is shown in FIG. That is, the lower half portion 15 and the wellhead are arranged such that a cap nut 17 for attaching a protective tube is concentrically disposed on the inner surface of the flange 6b or 7b of the wellhead, and the lower half of the protective tube is disposed on the flanges 6b and 7b. Fifteen flanges are brought into contact with each other, and both are bolted to each other. At this time, in order to facilitate the work of bolting the bottom portion of the lower half portion 15, a work port is appropriately prepared in the lower half portion 15 in advance. When the installation of the lower half portion 15 is completed, the work port and the gap are covered with a rolled iron plate or the like so that the filler does not leak out.
[0020]
Next, mirror cutting is performed to provide an opening having a diameter that allows the tip propulsion device 2 to pass through the liner 4 along the inner periphery of the arrival wellhead 6. The mirror cutting is preferably performed by a method of fusing the liner 4. In this case, the outer peripheral ground of the liner plate 4 is preliminarily improved as described above, so that the mirror collapse and the natural ground collapse are prevented for the time being. However, in order to prevent unforeseen collapse accidents, a protective wall 18 is provided in advance on the inner periphery of the lower half 15 so that the collapse of the natural ground is stabilized at a repose angle of about 45 ° even in the worst case. Plan. Then, after the mirror cutting, the tip propulsion device 2 is promptly propelled as shown in FIG. 4 to enter the arrival wellhead 6 to close the wellhead and prevent the inflow of earth and sand and groundwater as much as possible. Thereafter, the protective wall 18 is removed. Accordingly, the protective wall 18 is bolted to facilitate removal.
[0021]
Next, mirror cutting is performed to provide an opening for allowing the tip propulsion device 2 to pass through the liner 4 along the inner periphery of the start shaft 7. After that, the tip propulsion device 2 is promptly entered into the start shaft 7, and further advanced to the state where it protrudes out of the intermediate shaft 3 (liner plate 4) as shown in FIG. 5, thereby closing the entrance of the start shaft 7, Prevent inflow of groundwater as much as possible.
[0022]
Thereafter, as shown in FIGS. 5 and 6, the upper half portion 16 is placed on the lower half portion 15 of the protective tube, and both the well port sides are bolted with cap nuts, and the lower half portion 15 and the upper half portion are fixed. No. 16 completes the protective tube by bolting the flanges. In this way, the construction method once exposes the tip propulsion device 2 in the intermediate shaft 3, so that if a construction failure or accident occurs, it is possible to take immediate action, ensuring safety and reliability. Is the method.
[0023]
In order to prevent the leakage of the filler, the protective pipe completed in the above process is sealed with a water-stopping mortar from the outside, and then the filler is densely poured into the ground in the protective pipe. Keep the same conditions as. The filler to be used is, for example, one having a normal curing speed in which cement and bentonite are mixed with water. In some cases, a fast-curing filler in which water glass and cement are mixed is used. Thereafter, the propulsion of the tube 1 is resumed and continued.
[0024]
According to this construction method, there were no troubles such as collapse of the natural ground related to the intermediate shaft 3, collapse accidents, damage to surrounding private houses, and the construction of the intermediate shaft before the pipe propulsion The significance of this was also great.
Next, the intermediate shaft leading type pipe propulsion method according to the invention described in claim 3 also propels the pipe body toward the reaching shaft by the cooperative action of the main pushing device installed at the starting shaft and the tip propelling device. In the pipe propulsion method, it is suitably implemented as a so-called penetration method. Of course, it is a condition that the intermediate shaft 3 that allows the pipe to pass therethrough is completely constructed before the tip propulsion device 2 reaches the intermediate position between the starting shaft and the reaching shaft. It is characterized in that the construction of the intermediate shaft 3 and the installation of the protective pipe are completed before the device 2 is reached. Therefore, time is not wasted compared to the method of waiting until preparation is completed while the tip propulsion device 2 is made to reach the intermediate shaft 3 as in the case of the large embodiment described above. In the case of this construction method, the following preparation is performed before the tip propulsion device 2 arrives.
[0025]
The main steps for implementing this method are shown in FIGS. The diameter of the intermediate shaft 3 adopting the penetration method this time is about 3.7m in consideration of the final manhole finish. When the intermediate shaft 3 is completed, the base shaft in the intermediate shaft is surveyed based on the planned passage position of the tip propulsion device 2 propelled by controlling the direction while surveying, and the bottom of the intermediate shaft is determined based on the survey result. That is, the gantry 14 is installed on the bottom concrete 5, and the lower half 20a of the protective tube and both ends 20b of the protective tube are mounted thereon (FIGS. 13 and 14). That is, since it is a construction method in which a protective tube is prepared in advance based on a planned passing position of the tip propulsion device 2 that is propelled, as a premise thereof, the propulsion control of the tip propulsion device 2 is highly accurate and highly reliable. It is required that surveying and direction control technology be established.
[0026]
Thereafter, mirror cutting is performed to provide an opening in the liner 4 through which the tip propulsion device 2 passes along the inner circumference of the tube end portion 20b on each of the arrival side and the start side. Mirror cutting is preferably performed by a method of fusing the liner 4, and when fusing, the fusing may be performed so that some of the liner end pieces (about 30 mm in the embodiment) remain from the joint between the tube end 20 b and the liner 4. good. Also in the case of this construction method, the outer peripheral ground of the liner plate 4 is initially improved in advance, and supplementary injection is performed at the arrival and start parts, and the tip propulsion device 2 has not yet reached the ground. There is also an advantage that the mountain is not disturbed, and the collapse of the mirror and the collapse of the natural mountain are prevented for the time being. However, in order to prevent unforeseen collapse accidents, a protective wall is provided in advance on the lower half portion of the inner end face of the pipe end portion 20b. Even in the worst case, the collapse of the natural ground is suppressed by the protective wall. It is also possible to stabilize at an angle of repose of about °. When the mirror cutting is completed, the inner end face of the pipe end portion 20b is immediately sealed with a protective wall, and a fast-hardening filler is filled in the pipe end portion 20b. Prevent outflow as much as possible. After the filler is fully cured, the protective wall is removed to release the seal. As the fast-curing filler, water glass that is hardened instantaneously and a cement-based filler are preferably used.
[0027]
Thereafter, the upper half of the protective tube is attached to complete the assembly of the protective tube 20. The details of the structure of the protective tube 20 are as shown in FIG. The protective tube 20 is designed and manufactured to have a strength that can withstand the weight of the tip propulsion device 2 and the tube 1 when they pass through. In order to prevent the filler from leaking out, the protective pipe completed in the above-mentioned process is sealed with a water mortar or the like from the inner and outer sides of the protective pipe, and then the filler is injected densely (FIG. 15). . Here, as a method for injecting the filler, first, a fast-hardening filler is filled in the range of the lower half portion 20a of the protective tube to prevent leakage of the filler from the welded portion between the protective tube and both end portions. Subsequently, a normally hardened filler (for example, cement or bentonite filler described above) is densely filled in the remaining space (upper half) of the protective tube. As a result, the inside of the protective pipe 20 is in the same condition as the natural ground, and accidents such as the collapse of the natural ground and the outflow of groundwater are prevented. Further, in order to prevent an unexpected accident, the reinforced concrete 8 is placed on the outer periphery of the pipe end portion 20b as shown in FIG. 18, or the lower part of the outer periphery of the protective tube 20 is shown in FIGS. It is also preferable to improve the yield strength of the protective pipe by placing the reinforced concrete 21 as described above.
[0028]
After all of the above preparations are completed, the tip propulsion device reaches the intermediate shaft, and passes through the protective tube 20 as shown in FIG. 17 without stopping, and is propelled to the next intermediate shaft or the reaching shaft. Will be continued.
Even in this method, troubles such as collapse of the natural ground related to the intermediate shaft 3, collapse accidents, damage to surrounding private houses are carried out, and preparations for installing protective pipes are completed before the tip propulsion device arrives. The construction period was shortened compared to the wellhead method. The two construction methods, the wellhead method and the penetrating method, shortened the construction period by about 1 month (3 months is about 2 months) compared to the case where 350 m pipe propulsion and construction of two intermediate shafts were performed by the conventional method. Was able to do.
[0029]
The present invention can also be applied or applied to the following.
(1) It is applicable not only to the intermediate shaft but also to starting and reaching shafts.
(2) Since the mirror cutting part may be not only a liner plate but also a steel sheet pile or the like, it is possible to carry out mountain retaining such as an intermediate shaft by a steel sheet pile method.
(3) Not only propulsion work but also shield work can be applied.
(4) A wellhead with a wellhead-type entrance packing is attached on the arrival side, and a mixed system can be used in which the start side is substituted with one end of a penetration-type protective pipe.
(5) The protective tube is not necessarily cylindrical.
[0030]
[Effects of the present invention]
According to the present invention, since it is a pipe propulsion method in which an intermediate shaft is provided in advance, it is possible to easily solve the problems of the intermediate shaft leading type as well as to enjoy its advantages and to facilitate the construction. In addition, efficiency is achieved, safety that does not cause a collapse accident, etc. is achieved, and excellent effects such as achieving a significant shortening of the construction period are achieved.
[Brief description of the drawings]
FIG. 1 is a sectional view showing a first step of a wellhead type pipe propulsion method according to the present invention.
FIG. 2 is a cross-sectional view showing the next step of the pipe propulsion method.
FIG. 3 is a cross-sectional view showing a process of a pipe propulsion method.
FIG. 4 is a cross-sectional view showing a process of a pipe propulsion method.
FIG. 5 is a cross-sectional view showing a process of a pipe propulsion method.
FIG. 6 is a cross-sectional view showing a process of the pipe propulsion method.
FIG. 7 is a plan view showing an installation state of the protective pipe.
FIG. 8 is a cross-sectional view showing a portion of an entrance packing at a reaching pit.
FIG. 9 is a front view showing a part of the entrance packing of the arrival tunnel.
FIG. 10 is a cross-sectional view showing a part of the entrance packing of the start pit.
FIG. 11 is a front view showing a part of the entrance packing at the arrival tunnel.
FIG. 12 is a front view showing how the protective pipe is assembled.
FIG. 13 is a cross-sectional view showing a first step of the penetration type tube propulsion method of the present invention.
FIG. 14 is a cross-sectional view showing the next step of the pipe propulsion method.
FIG. 15 is a cross-sectional view showing a process of the pipe propulsion method.
FIG. 16 is a cross-sectional view showing a process of the pipe propulsion method.
FIG. 17 is a cross-sectional view showing a process of the pipe propulsion method.
FIG. 18 is a plan view showing an installation state of the protective pipe.
FIG. 19 is a view on arrow 19-19 in FIG. 17;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Tube 2 Tip propulsion apparatus 3 Middle shaft 4 Liner 5 Bottom concrete 6 Reaching shaft 7 Starting shaft 14 Base 15 Lower half 16 of the protective pipe 16 Upper half of the protective pipe

Claims

発進立坑に設置した元押し装置と先端推進装置との協同作用により管体を到達立坑に向かって推進させる管推進工法において、
発進立坑と到達立坑との中間位置に、管体を通過させる中間立坑を、先端推進装置の到達以前に構築すること、
先端推進装置が中間立坑のライナーへ到達した段階で、同先端推進装置の位置を確認して立坑内基線の測量を行い、前記の測量結果に基づいて到達坑口と発進坑口を中間立坑内に設置すること、
中間立坑の底部に架台を設置し、その上に前記到達坑口と発進坑口を連絡する防護管の下半部を取り付けること、
前記到達坑口の内周に沿ってライナーに先端推進装置を通過させる開口を設ける鏡切りを行い、先端推進装置を中間立坑内へ進ませること、
発進立坑の内周に沿ってライナーに先端推進装置を通過させる開口を設ける鏡切りを行い、先端推進装置を中間立坑の外まで進ませること、
前記防護管の下半部の上に上半部を取付け、密閉された防護管の中に充填材を注入し、その後管体の推進を続行すること、
をぞれぞれ特徴とする、中間立坑先行型の管推進工法。In the pipe propulsion method of propelling the pipe body toward the arrival shaft by the cooperative action of the main pushing device installed at the starting shaft and the tip propulsion device,
Build an intermediate shaft that allows the pipe to pass through the intermediate position between the starting shaft and the reaching shaft before the tip propulsion device arrives,
When the tip propulsion device reaches the liner of the intermediate shaft, check the position of the tip propulsion device and measure the baseline in the shaft, and based on the above survey results, install the arrival shaft and the starting shaft in the intermediate shaft To do,
A base is installed at the bottom of the intermediate shaft, and the lower half of the protective pipe connecting the arrival well and the start well is installed on it;
Performing a mirror cutting to provide an opening that allows the tip propulsion device to pass through the liner along the inner circumference of the arrival shaft, and advance the tip propulsion device into the intermediate shaft,
Mirror cutting to provide an opening that allows the tip propulsion device to pass through the liner along the inner periphery of the starting shaft, and advance the tip propulsion device to the outside of the intermediate shaft,
Mounting the upper half on the lower half of the protective tube, injecting filler into the sealed protective tube, and then continuing to propel the tube;
This is a pipe propulsion method with an intermediate shaft leading type.

到達坑口と発進坑口には、補強コンクリートを打設し、また、先端推進装置を到達坑口に通過させる以前、及び発進坑口へ前進させる以前に各坑口にエントランスパッキンを取付けておき、そこを先端推進装置を通過させてから防護管で密閉し、速硬性または通常硬化の充填材で空隙を充填することを特徴とする、請求項１に記載した中間立坑先行型の管推進工法。Reinforced concrete is placed at the arrival wellhead and the starting wellhead, and the entrance packing is attached to each wellhead before the tip propulsion device is passed through the reaching wellhead and before it is advanced to the starting wellhead. The intermediate shaft leading type pipe propulsion method according to claim 1, wherein the pipe is closed with a protective pipe after passing through the apparatus, and the gap is filled with a fast-curing or normal-curing filler.

到達坑口と発進坑口には、先端推進装置を到達坑口に通過させる以前、及び発進坑口へ前進させる以前に各坑口にエントランスパッキンを取付けておき、そこを先端推進装置を通過させてから防護管で密閉し、速硬性または通常硬化の充填材で空隙を充填することを特徴とする、請求項１に記載した中間立坑先行型の管推進工法。At the arrival wellhead and starting wellhead, an entrance packing is attached to each well before passing the tip propulsion device to the arrival wellhead and before moving to the starting wellhead. 2. The intermediate shaft leading pipe propulsion method according to claim 1, wherein the gap is filled with a fast-curing or normal-curing filler.

発進立坑に設置した元押し装置と先端推進装置との協同作用により管体を到達立坑に向かって推進させる管推進工法において、
発進立坑と到達立坑との中間位置に、管体を通過させる中間立坑を、先端推進装置の到達以前に構築すると共に以下の準備を行うこと、
先端推進装置の通過予定位置に基づいて中間立坑内基線の測量を行い、前記の測量結果に基づいて中間立坑の底部に架台を設置し、その上に防護管の下半部と管両端部を取り付けること、
到達側と発進側の管端部の内周に沿ってライナーに先端推進装置を通過させる開口を設ける鏡切りを行い、防護管の上半部を取付け、かくして密閉された防護管の内部へ充填材を注入すること、
以上の準備を完了した後に先端推進装置を中間立坑にまで到達させ、更に防護管の中を通過させて管体の推進を継続すること、
をぞれぞれ特徴とする、中間立坑先行型の管推進工法。In the pipe propulsion method of propelling the pipe body toward the arrival shaft by the cooperative action of the main pushing device installed at the starting shaft and the tip propulsion device,
Before the arrival of the tip propulsion device, construct the intermediate shaft that allows the pipe to pass through the intermediate position between the starting shaft and the reaching shaft, and make the following preparations:
Based on the planned passage position of the tip propulsion device, survey the baseline in the intermediate shaft, install a pedestal at the bottom of the intermediate shaft based on the above survey results, and place the lower half of the protective tube and both ends of the tube on it. Installing,
Mirror cut to provide an opening for the tip propulsion device to pass through the liner along the inner circumference of the tube end on the arrival side and the start side, and attach the upper half of the protection tube, thus filling the inside of the sealed protection tube Injecting material,
After the above preparation is completed, the tip propulsion device reaches the intermediate shaft, and further passes through the protective pipe to continue the propulsion of the pipe body.
This is a pipe propulsion method with an intermediate shaft leading type.

ライナーの鏡切りの直後に管端部の坑内側端面を密閉し、速硬性の充填材を管端部の中に充填し、同充填材が硬化した後に前記密閉を解くことを特徴とする、請求項４に記載した中間立坑先行型の管推進工法。Immediately after mirror cutting of the liner, the inner end face of the pipe end is sealed, a fast-curing filler is filled into the pipe end, and the sealing is released after the filler is cured, An intermediate shaft leading type pipe propulsion method according to claim 4.

防護管の内部への充填材の注入は、先ず防護管の下半部に速硬性の充填材を充填し、続いて防護管の残る空隙部に通常硬化の充填材を密に充填することを特徴とする、請求項４に記載した中間立坑先行型の管推進工法。The injection of filler into the inside of the protective tube is to first fill the lower half of the protective tube with fast-hardening filler, and then closely fill the remaining space of the protective tube with normally hardened filler. 5. The intermediate shaft advance type pipe propulsion method according to claim 4,

防護管の内部への充填材の注入は、防護管の下半部に通常硬化の充填材を充填し、続いて防護管の残る空隙部にも通常硬化の充填材を密に充填することを特徴とする、請求項４に記載した中間立坑先行型の管推進工法。Filling the inside of the protective tube is to fill the lower half of the protective tube with normally hardened filler, and then fill the remaining space of the protective tube with normal hardened filler densely. 5. The intermediate shaft advance type pipe propulsion method according to claim 4,