JP2004204523A

JP2004204523A - Cutoff method and cutoff structure of joint section between ring in widening segment

Info

Publication number: JP2004204523A
Application number: JP2002374090A
Authority: JP
Inventors: Masayoshi Nakagawa; 雅由中川; Masanori Matsuura; 正典松浦; Takayoshi Aoyanagi; 孝義青柳; Hiroki Someya; 洋樹染谷; Hirohide Hashimoto; 博英橋本; Hirosuke Asano; 裕輔浅野; Takashi Kunito; 崇國藤
Original assignee: Kajima Corp; Ishikawajima Kenzai Kogyo Co Ltd; Ishikawajima Construction Materials Co Ltd
Current assignee: Kajima Corp; Ishikawajima Kenzai Kogyo Co Ltd; Ishikawajima Construction Materials Co Ltd
Priority date: 2002-12-25
Filing date: 2002-12-25
Publication date: 2004-07-22
Anticipated expiration: 2022-12-25
Also published as: JP4030866B2

Abstract

PROBLEM TO BE SOLVED: To prevent an infiltration into a segment of groundwater and soil and sand from a fastening hole when the movable section of the widening segment is widened. SOLUTION: The fastening of fastening means 39 and 40 connecting a main girder 31 for the movable section of one widening segment in two adjacent widening segments and the main girder 33 for the movable section of the other widening segment through bolt inserting holes 34 formed to these main girders is released. The bolt inserting hole 34 formed to the main girder 31 for one segment is closed by a plug member 50. The movable section of one segment and the movable section of the other segment are moved successively to the outside in the tunnel diametral direction respectively and projected to an overbreak section. The plug member 50 is removed, and the main girders 31 nd 33 for the movable sections of the two segments projected to the overbreak section are fastened mutually by the fastening means again. COPYRIGHT: (C)2004,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は、拡幅坑用として設置される、拡幅セグメントにおけるリング間継手部の止水方法および止水構造に関するものである。
【０００２】
【従来の技術】
シールド掘削機を用いて構築する埋設管渠やトンネル等において、構造上、施工上の制約から、途中に通常部以上の断面を有する拡幅部が必要となる場合がある。例えば、道路や鉄道のトンネルの非常駐車帯や引き込み線やランプ部、共同溝等のケーブル接続部や路線分岐部等を設置する場合である。
【０００３】
そして、拡幅部を形成する方法の一つとして、掘削途中で掘削面積を自由に拡幅できるシールド掘削機を用いて必要部分のみを拡幅断面で掘削するとともに、この拡幅断面部分に拡幅可能な特殊なセグメントである拡幅セグメントを設け、シールド掘削機が前方へ所定距離進んだところで、拡幅セグメントの可動部をトンネル径方向外方へ移動させて拡幅することにより、トンネル等の途中に拡幅を得る方法がある。
ところで、従来、セグメントのリング間継手部分どうしを連結するにあたって、ボルトとナットとの組み合わせたものを利用するのが一般的であった（例えば、特許文献１参照。）。
【０００４】
【特許文献１】
特公平４−３６２３９号公報（第２頁）
【０００５】
【発明が解決しようとする課題】
上述した従来のセグメントのリング間継手部構造にあっては、単に、ボルトとナットとの組み合わせによって連結する構造であり、このような継手部構造を、拡幅セグメントの可動部の連結に採用すると、ボルトとナットとの連結を解いて可動部を拡幅する場合に、ボルト挿通孔から地下水や土砂がセグメントの内部へ浸入してしまう課題があった。
【０００６】
本発明は、上記のような従来の問題に鑑みなされたものであって、拡幅セグメントの可動部を拡幅する場合、締結孔から地下水や土砂がセグメントの内部に浸入するのを防止することができる、拡幅セグメントにおけるリング間継手部の止水方法および止水構造を提供することを目的とするものである。
【０００７】
【課題を解決するための手段】
本発明は、上記のような課題を解決するために、以下のような手段を採用している。
すなわち、請求項１に係る拡幅セグメントにおけるリング間継手部の止水方法は、予め掘削された余掘り部へ張り出すように拡幅セグメントの可動部をトンネル径方向外方へ移動させるときの拡幅セグメントどうしを連結する、拡幅セグメントにおけるリング間継手部の止水方法であって、隣接する２つの拡幅セグメントのうちの一方の拡幅セグメントの可動部の主桁と他方の拡幅セグメントの可動部の主桁を、それら主桁にそれぞれ形成された同軸状の締結孔を介して連結する締結手段の締結を解く工程と、前記一方の拡幅セグメントの可動部の主桁に形成された締結孔を栓部材で塞ぐ工程と、該一方の拡幅セグメントの可動部をトンネル径方向外方へ移動させて前記余掘り部へ張り出させる工程と、前記他方の拡幅セグメントの可動部をトンネル径方向外方へ移動させて前記余掘り部へ張り出させる工程と、前記一方の拡幅セグメントの可動部の主桁の締結孔を塞いだ栓部材を取り外す工程と、共に余掘り部へ張り出させた前記２つの拡幅セグメントの可動部の主桁どうしを再び前記締結手段で締結する工程とを備えることを特徴としている。
この場合、拡幅セグメントの可動部をトンネル径方向外方へ移動させるとき、事前に、締結孔を栓部材で塞いでいるので、可動部の締結孔から拡幅セグメント内に地下水や土砂等が浸入するのを防止できる。
【０００８】
請求項２に係る拡幅セグメントにおけるリング間継手部の止水方法は、請求項１記載の方法において、前記締結手段はボルト部材とナット部材であり、前記拡幅のセグメントの可動部の主桁に形成された締結孔は、ボルト挿通孔であることを特徴としている。
この場合、締結手段として、使用例が多くかつ信頼性が高いボルト部材とナット部材による締結であるので、継手部の健全性を高め得るとともにコストも低減できる。
【０００９】
請求項３に係る拡幅セグメントにおけるリング間継手部の止水方法は、請求項１または２記載の方法において、前記栓部材の先端が、前記一方の拡幅セグメントの可動部の主桁の外側面と面一となるように設置されることを特徴としている。
この場合、栓部材の先端が主桁の外側面と面一になっているので、例えば、隣接する拡幅セグメントの主桁どうしの接合面にシール材が介在されている場合にであっても、該シール部材を損傷させない。
【００１０】
請求項４に係る拡幅セグメントにおけるリング間継手部の止水構造は、予め掘削された余掘り部へ張り出すようにトンネル径方向外方へ移動される、隣接する拡幅セグメントの可動部どうしを、該拡幅セグメントの可動部の主桁にそれぞれ形成された同軸状の締結孔にボルトを挿通させて連結する拡幅セグメントにおけるリング間継手部の止水構造であって、前記隣接する２つの拡幅セグメントのうちの一方の拡幅セグメントの可動部の主桁の内側面に該主桁に形成された締結孔と同軸状に取り付けられて、該締結孔を塞ぐ栓部材を装着可能な円筒部材と、該円筒部材内に挿通されて、その先端が前記隣接する拡幅セグメントの可動部どうしの主桁にそれぞれ形成された前記締結孔を挿通するボルト部材と、前記隣接する２つの拡幅セグメントのうちの他方の拡幅セグメントの可動部の主桁の内側面側から前記ボルト部材の先端部にねじ合わされるナット部材と、を備えることを特徴としている。
この場合、一方の拡幅セグメントの可動部の主桁の内側面に円筒部材を設けているので、拡幅セグメントの可動部をトンネル径方向外方へ移動させるとき、この円筒部材を利用して、拡幅セグメントの可動部のボルト挿通孔を塞ぐよう先負材を装着することができ、前述した請求項１記載の方法を好適に実施できる。
【００１１】
請求項５に係る拡幅セグメントにおけるリング間継手部の止水構造は、請求項４記載のものにおいて、前記ナット部材は、前記隣接する２つの拡幅セグメントのうちの他方の拡幅セグメントの主桁の内側面に、ホルダによって、主桁に形成された前記締結孔と同軸状かつ回転可能に取り付けられていることを特徴としている。
この場合、ナット部材を回転可能に取り付けているので、拡幅セグメントの可動部をトンネル径方向外方へ移動させるとき、ボルト部材との締結を容易に解くことができ、かつ、ボルト部材との締結を解いたときでも、拡幅セグメントの可動部にそのまま取り付けられたままであるので、ナット部材の管理も容易になる。
【００１２】
請求項６に係る拡幅セグメントにおけるリング間継手部の止水構造は、請求項５記載のものにおいて、前記ナット部材は、底部を有する袋状であって、前記拡幅セグメントのうちの他方の拡幅セグメントの可動部の主桁の内側面にシール部材を介して液密に取り付けられていることを特徴としている。
この場合、袋状のナット部材を用いていること、ナット部材と拡幅セグメントの可動部の主桁との間にシール部材を介在させていることから、一方あるいは他方の拡幅セグメントの可動部を移動させるときに、ナット部材が取り付けられた側のボルト挿通孔を液密の保持し、これにより、ボルト挿通孔から地下水や土砂が浸入するのを防止できる。
【００１３】
請求項７に係る拡幅セグメントにおけるリング間継手部の止水構造は、請求項５または６記載のものにおいて、前記ナット部材には、前記他方の拡幅セグメントの可動部の主桁の締結孔に挿入され、内部に前記ボルト部材を挿通させる円筒部が形成されていることを特徴としている。
この場合、リング状に組み合わせた拡幅セグメントが例えば地圧の影響等で変形したり位置ずれする場合であって、一旦、締結したボルト部材とナット部材とが外しにくくなった場合でも、容易にボルト部材とナット部材との締結を解くことができる。
【００１４】
請求項８に係る拡幅セグメントにおけるリング間継手部の止水構造は、請求項４記載のものにおいて、前記他方の拡幅セグメントの可動部の主桁の前記締結孔の内端部には、前記主桁の材料よりも軟らかい材料からなり、かつ、締結孔よりも小径のボルト挿通孔を備える円筒体が取り付けられていることを特徴としている。
この場合も、締結孔にセットした円筒体が容易に変形するので、請求項７と同様に、容易にボルト部材とナット部材との締結を解くことができる。
【００１５】
【発明の実施の形態】
以下、図面に示す本発明の実施の形態について説明する。
＜発明の第１の実施の形態＞
図１〜図９は発明の第１の実施形態を示す。
図１は、シールド掘削機１で、拡幅坑２を有するトンネル３を掘削する状況を示す図である。この図１に示すように、シールド掘削機１は、掘削機本体４，掘削用のカッタ５、コピーカッタ６等で構成される。
【００１６】
掘削用カッタ５は、筒状の掘削機本体４の端面に設けられる。コピーカッタ６は、例えば、掘削用カッタ５の一部として設けられ、必要に応じてシールド掘削機１の側方に伸長可能に構成される。また、掘削用カッタ５は、面板スライド機構によって、掘削機本体４の周方向にスライド可能になっている。
【００１７】
図１（ａ）は、トンネル３の通常坑９を掘削する状況を示す。通常坑９とは、トンネル３を構築するために掘削される坑道のうち、通常の周方向断面を有する部分である。図１（ａ）に示すように、シールド掘削機１は、コピーカッタ６を掘削用カッタ５内に格納した状態で地山１０を掘削し、トンネル３の通常坑９を形成する。掘削機本体４の後部では、通常坑９の内部にセグメント１１が設置される。
【００１８】
図１（ｂ）は、トンネル３の拡幅坑２を掘削する状態を示す。図２は、図１（ｂ）のＸーＸ線に沿った断面を示す。拡幅坑２とはトンネル３を構築するために掘削される坑道のうち、通常坑９より周方向断面が拡幅された部分であり、図１（ｂ）、図２に示すように、掘削機本体４の外側に余掘り部１２が形成される。
【００１９】
図１（ｂ）に示すように、シールド掘削機１は、コピーカッタ６を掘削用カッタ５の径方向外方に伸長させ、掘削用カッタ５で通常断面を掘削しつつ、コピーカッタ６で余掘り部１２を掘削して、トンネル３の拡幅坑２を形成する。なお、掘削する余掘り部１２の幅に応じて、コピーカッタ６と面板スライド機構とを併用して余掘り部１２を掘削してもよい。
なお、拡幅坑２の内壁と掘削機本体４の間の余掘り部１２には、必要に応じて、充填材を充填する。
【００２０】
掘削機本体４の後部では、通常坑９拡幅坑２との境界部の通常坑９の内壁に、必要に応じて、調整セグメント１３を有する調整用セグメントリング１４が設置される。
【００２１】
調整用セグメントリング１４の調整用セグメント１３は、拡幅用セグメントリング１６の拡幅セグメント１７に隣接して設置される。調整セグメント１３は、通常坑９のセグメントリング１１と拡幅セグメント１５との間をなめらかにつなぐための部材である。図１（ｃ）に示すように、調整用セグメント１３の内周面は、通常坑９のセグメント１１の内周面から拡幅セグメント１７の内周面に向けた勾配を有する。
【００２２】
図１（ｃ）は、拡幅用セグメントリング１６を設置する状況を示す。図１（ｃ）に示すように、図１（ｂ）に示す状態から地山１０をさらに掘削し、掘削機本体４の後部で拡幅セグメント１７を有する拡幅用セグメントリング１６を設置していく。
【００２３】
図３は、拡幅用セグメントリング１６の概略を示す斜視図である。図４、図５にも示すように、拡幅用セグメントリング１６は、通常坑９に設置されるセグメントと同様のセグメント１８と、内周面側に拡幅部材２０を有する拡幅セグメント１７で構成される。拡幅セグメント１７は、拡幅用セグメントリング１６の径方向外方へ移動可能な可動部１７Ａと移動しない固定部１７Ｂとからなっている。
また、拡幅セグメント１７の可動部１７Ａと固定部１７Ｂとの間には、可動部１７Ａの移動を許容するようヒンジ部２１が設けられる。
【００２４】
図１（ｃ）に示すように、拡幅用セグメントリング１６は、余掘り部１２の内側に設置される。このとき、拡幅用セグメントリング１６は、図３に示す状態であり、拡幅用セグメントリング１６の外径は、通常坑９に設置されたセグメントリングや調整用セグメントリング１４の外径と同じである。
【００２５】
図１（ｃ）に示す状態のとき、トンネル３の軸方向に隣接する通常のセグメントリングどうしは、リング間継手部が例えばボルト部材とナット部材からなる締結手段によって連結される。隣接する拡幅セグメントリング１６どうしも、リング間継手部が前記同様に締結手段によって連結される。
ただし、隣接する拡幅セグメントリング１６どうしのうち拡幅セグメント１７の可動部１７Ａどうしのリング間継手部は、可動部１７Ａが移動するときにも、セグメント内に地下水等が浸入しないよう止水機能を発揮できる特殊な構造になっている。
【００２６】
この止水構造について説明する。図６は、図１（ｃ）のＹに示す部分の拡大図である。図６において符号３０は隣接する拡幅セグメントのうち一方の拡幅セグメントの可動部１７Ａのスキンプレート、符号３１は一方の拡幅セグメントの可動部１７Ａの主桁、符号３２は隣接する拡幅セグメント１７のうち他方の拡幅セグメントの可動部１７Ａのスキンプレート、符号３３は他方の拡幅セグメントの可動部１７Ａの主桁である。主桁３１、３３の所定個所には、それぞれ締結用のボルト部材が挿通されるボルト挿通孔３４が形成されている。
【００２７】
一方の拡幅セグメント１７の可動部１７Ａの主桁３１の内側面には、円筒部材３５がボルト挿通孔３４と同軸状に例えば溶接により取り付けられている。円筒部材３５は、後工程で一方の拡幅セグメント１７の主桁３１のボルト挿通孔３４を液密に塞ぐための後述する栓部材５０を装着するためのものである。
円筒部材３５は、内径がボルト挿通孔よりも大径とされた主桁側の小径部３６と、内径が小径部３６よりもさらに大径とされた主桁側とは逆側の大径部３７とを有する。大径部３７は、外側に向けて漸次拡径するようにテーパー状に形成されるとともに、内周には雌ねじ部３８が形成されている。
【００２８】
円筒部材３５にはボルト部材３９が挿通されるが、このボルト部材３９は、先端が隣接する拡幅セググメントの主桁３１、３３にそれぞれ形成されたボルト挿通孔３４を挿通して、他方の拡幅セグメントの主桁３３の内側に突出している。
【００２９】
一方、隣接する２つの拡幅セグメント１７のうちの他方の拡幅セグメントの可動部１７Ａの主桁３３の内側面側にはナット部材４０が取り付けられ、このナット部材４０は前記ボルト部材３９の先端部にねじ合わされている。
このように、ボルト挿通孔３４に挿通されたボルト部材３９の先端にナット部材４０がねじ合わされ、強く締結されることで、隣接する２つの拡幅セグメント１７の可動部１７Ａの主桁３１、３３どうしは連結される。すなわち、ボルト部材３９とナット部材４０とは、拡幅セグメントのリング間継手部の締結手段Ｔを構成している。
【００３０】
ナット部材４０は、底部４１を有する袋状に形成されたもので、前記他方の拡幅セグメントの主桁３３の内側面側にはフランジ部４２が形成され、このフランジ部４２は、図７に示すように、２つ割りのリング４３ａ、４３ａからなるホルダ４３に嵌合される。そして、このホルダ４３が主桁３３の内側面に例えば溶接等の固定手段で取り付けられることで、ナット部材４０は、主桁３３のボルト挿通孔３４に同軸状となるようにかつ回転可能に支持される。
【００３１】
ナット部材４０のフランジ部４２側には、円筒部４４がフランジ部４２よりもさらに外方に突出するように形成されている。円筒部４４は、他方の拡幅セグメント１７の主桁３３のボルト挿通孔３４内に挿入されるもので、その内部には前記ボルト部材３９が若干の遊びをもって挿通される。また、円筒部４４の内周面にも必要に応じて雌ねじが形成される。
【００３２】
さらに、ナット部材４０と主桁３３との間には、ナット部材４０に形成されたリング溝４０ａに嵌合されたシール部材４５が介装され、これにより、ナット部材４０と主桁３３とは液密状態に保持されている。
【００３３】
上述したようにボルト部材３９とナット部材４０によって、拡幅する前の拡幅セグメント１７の可動部１７Ａは互いに連結されているが、その後、シールド掘削機１が前方へ所定距離進んだところで、拡幅セグメント１７の可動部１７Ａが余掘り部１２へ張り出すようにトンネル径方向外方へ移動させて拡幅される際に、事前に、これらボルト部材３９とナット部材４０と締結が解かれる。
【００３４】
すなわち、ナット部材４０が締結とは逆方向へ回転されることで、ボルト部材３９とのねじ合わせが解かれる（図６（ｂ）参照）。
【００３５】
この場合、リング状に組み合わされた拡幅セグメント１７が例えば地圧の影響等で変形したり位置ずれして、隣接する拡幅セグメント１７の主桁３１，３３のボルト挿通孔３４どうしが同軸状からずれて、締結したボルト部材３９とナット部材４０とが外れにくくなるおそれがある場合でも、ナット部材３９に円筒部４４が一体に設けられ、ボルト部材３９が、直接、主桁３３のボルト挿通孔３４に接触しないようになっているので、容易にボルト部材３９とナット部材４０との締結を解くことができる。
【００３６】
また、前記ナット部材４０はホルダ４３によりを回転可能に取り付けられているので、ナット部材４０を回転させるだけで、ボルト部材３９との締結を容易に解くことができ、しかも、取り外した後においても、ナット部材４０は主桁３３に取り付けられた状態を維持できるので、同ナット部材４０の管理が容易になる。
【００３７】
次いで、前記ボルト部材３９を取り外した一方の拡幅セグメント１７の主桁３１に形成されたボルト挿通孔３４を栓部材５０で塞ぐ。栓部材５０は、図６（ｃ）、図７に示すように、ボルト挿通孔３４に挿入される栓本体５１と、前記円筒部材３５の小径部３６に挿入される大径頭部５２とからなっており、大径頭部５２を、拡幅セグメント１７の内方から前記円筒部材３５の大径部に螺合される抜け止め部材５３によって押圧されることで固定される。
【００３８】
ここで、図６（ｃ）に示すように、栓部材５０の先端は、一方の拡幅セグメントの１７の主桁３１の外側面と面一となるように設置される。
【００３９】
その後、拡幅セグメントリング１６内に図示せぬジャッキがセットされ、このジャッキを作動させることによって、一方の拡幅セグメント１７の可動部１７Ａをトンネル径方向外方へ移動させて余掘り部１２へ張り出させる（図５参照）。
【００４０】
この場合、事前に、一方の拡幅セグメント１７の可動部１７Ａのボルト挿通孔３４を栓部材５０で塞いでいるので、該可動部１７Ａのボルト挿通孔３４から拡幅セグメント内に地下水や土砂等が浸入するのを防止できる。
また、栓部材５０の先端が主桁３１の外側面と面一になっているので、例えば、隣接する拡幅セグメント１７の主桁３１、３３どうしの接合面にシール部材５４が介在されている場合であっても、該シール部材５４を損傷させない（図５参照）。
ちなみに、栓部材５０の先端が主桁３１のボルト挿通孔３４よりも奥側に位置する場合には、拡幅セグメント１７の可動部１７Ａを移動させるとき、ボルト挿通孔３４の外縁の露出するエッジ部分によって前記シール部材５４を損傷させるおそれが出てくる。
なお、上述の説明では、栓部材５０の先端が主桁３１の外側面と面一にしているが、これに代わって図６（ａ）〜（ｃ）中２点鎖線で示すように、主桁３１のボルト挿通孔３４の外縁に、主桁３３側に向かって拡径するテーパー部３４ａを設け、このテーパー部３４ａの奥側の位置まで前記栓部材５０の先端が至るように設定しても良い。
このように主桁３１のボルト挿通孔３４にテーパー部３４ａを設けることにより、例えば、加工時にボルト挿通孔３４の外縁にバリが生じた場合でも、そのバリによって、一方の拡幅セグメント１７の可動部１７Ａをトンネル径方向外方へ移動させる際にシール部材５４が損傷されるのを未然に防止することができる。
【００４１】
次いで、前記他方の拡幅セグメント１７の可動部１７Ａもトンネル径方向外方へ移動させて前記余掘り部１２へ張り出させる。
この場合、ナット部材４０として袋状のものを用いていること、ナット部材４０と拡幅セグメント１７の主桁３３との間にシール部材４５を介在させていることから、一方あるいは他方の拡幅セグメント１７の可動部１７Ａを移動させるときに、ナット部材４０が取り付けられた側の主桁３３のボルト挿通孔３４を液密の保つことができ、これにより、該ナット部材４０が取り吊られた側のボルト挿通孔３４から地下水や土砂がセグメントの内方へ浸入するのを防止できる。
【００４２】
次いで、一方の拡幅セグメント１７の可動部１７Ａの主桁３１のボルト挿通孔３４を塞いでいた栓部材５０を、抜け止め部材５３のねじ止めを緩めることで取り外す。このとき、必要に応じて、栓部材５０の大径頭部５２に形成されたねじ部５２ａに、治具を係合させて取り外す。
【００４３】
その後、共に余掘り部１２へ張り出させた前記隣接する２つの拡幅セグメント１７の可動部１７Ａの主桁３１、３３どうしを再び前記ボルト部材３９とナット部材４０を用いて締結する（図６（ａ）参照）。
以上のようにしてトンネルを掘り進む。
【００４４】
なお、ナット部材４０としては、図６（ａ）図７に示したものの場合、円筒部４４を備えるものを用いているが、一旦組み合わせた拡幅セグメント１７自体に変形が少なく、ボルト部材とナット部材との締結の解除が容易に行える可能性が高い場合には、図８に示すように、円筒部を有しないナット部材５５を利用してもよい。
さらに、ナット部材の他の例としては、図９に示すように、フランジ５６ａ付きの袋ナット５６が挙げられ、このようなナット部材を利用してもよい。
【００４５】
＜発明の第２に実施形態＞
図１０は、本発明の第２の実施の形態を示す。
この実施の形態は、トンネル周囲の地盤等の関係から、ナット部材６０が取り付けられる側のボルト挿通孔３４からセグメント内へ地下水等の浸入のおそれが少ない場合の例である。
なお、図６で示した構成要素と同一構成要素については同一符号を付してその節名を省略する。
【００４６】
ここでは、他方の拡幅セグメント１７の可動部１７Ａの主桁３３のボルト挿通孔３４の内端部に凹部６０を設け、この凹部６０に、主桁３１、３３の材料よりも軟らかい材料からなりかつボルト挿通孔３４よりも小径のボルト挿通孔６１ａを備える円筒体６１が取り付けられている。
この場合でも、拡幅セグメント１７が変形したり位置ずれして、主桁３１，３３のボルト挿通孔３４どうしが同軸状からずれ、ボルト部材３９が主桁３３のボルト挿通孔３４との端縁に噛み込んで、締結したボルト部材３９とナット部材６２とが外れにくくなるといった事態を、凹部６０にセットした円筒体６１が容易に変形することで回避できる。
【００４７】
なお、前述の実施の形態はあくまで本発明の例示であり、本発明は必要に応じて適宜設計変更可能である。
例えば、前述した実施の形態では、拡幅セグメント１７の可動部１７ａのリング間継手部の締結手段として、ボルト部材とナット部材を用いているが、これに限られることなく、他の締結手段であってもよく、用は締結孔を利用した締結手段であれば本発明は適用可能である。
【００４８】
【発明の効果】
以上説明したように本発明によれば、隣接する拡幅セグメントのうちの先に可動部をトンネル径方向外方へ移動させるである、一方の拡幅セグメントの可動部の主桁の締結孔を栓部材で塞ぐので、可動部の主桁の締結孔から拡幅セグメント内に地下水や土砂等が浸入するのを防止できる。
【図面の簡単な説明】
【図１】本発明の第１の実施の形態を示し、シールド掘削機でトンネルを掘削する状況を示す断面図である。
【図２】図１（ｂ）のＸーＸ線に沿う断面図である。
【図３】拡幅セグメントリングの概略斜視図である。
【図４】拡幅セグメントを示すもので、可動部を移動させる前の側面図である。
【図５】拡幅セグメントを示すもので、可動部を移動させた後の側面図である。
【図６】拡幅グメントの可動部の主桁のリング間継手部の構造を示す断面図である。
【図７】拡幅グメントの可動部の主桁のリング間継手部の構造を示す斜視図である。
【図８】ナット部材の変形例を示す斜視図である。
【図９】ナット部材の他の変形例を示す斜視図である。
【図１０】本発明の第２の実施の形態を示し、拡幅グメントの可動部の主桁のリング間継手部の構造を示す断面図である。
【符号の説明】
１シールド掘削機２トンネル
１６拡幅用セグメントリング１７拡幅セグメント
１７Ａ可動部１７Ｂ固定部
３１、３３主桁３４ボルト挿通孔（締結孔）
３５円筒部材３９ボルト部材
４０ナット部材４１底部
４２フランジ部４３ホルダ
４４円筒部４５シール部材
５０栓部材５１栓本体
５２大径頭部５３抜け止め部材
６１円筒体６２ナット部材
Ｔ締結手段[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a water stop method and a water stop structure for a joint portion between rings in a widened segment, which is installed for a widening shaft.
[0002]
[Prior art]
In buried pipes and tunnels constructed using a shield excavator, there are cases where a widened portion having a cross section larger than the normal portion is required in the middle due to structural and construction restrictions. For example, it is a case where an emergency parking zone of a road or a railway tunnel, a lead-in line, a ramp part, a cable connection part such as a common groove, a route branch part, etc.
[0003]
And as one of the methods of forming the widened portion, only a necessary portion is excavated with a widened cross section using a shield excavator that can widen the excavation area freely during excavation, and a special portion capable of widening the widened cross section. A method of obtaining a widening in the middle of a tunnel or the like by providing a widening segment as a segment and moving the movable part of the widening segment outward in the radial direction of the tunnel when the shield excavator has advanced a predetermined distance forward. is there.
By the way, conventionally, when connecting the inter-ring joint portions of the segments, it is common to use a combination of a bolt and a nut (for example, refer to Patent Document 1).
[0004]
[Patent Document 1]
Japanese Examined Patent Publication No. 4-36239 (page 2)
[0005]
[Problems to be solved by the invention]
In the conventional inter-ring joint part structure of the segment described above, it is a structure that is simply connected by a combination of a bolt and a nut. When such a joint part structure is used for connecting the movable part of the widened segment, When the connection between the bolt and the nut is released to widen the movable part, there is a problem that groundwater or earth and sand enters the segment from the bolt insertion hole.
[0006]
The present invention has been made in view of the above-described conventional problems, and when widening the movable portion of the widened segment, it is possible to prevent groundwater or earth and sand from entering the inside of the segment from the fastening hole. An object of the present invention is to provide a water stopping method and a water stopping structure for an inter-ring joint portion in a widened segment.
[0007]
[Means for Solving the Problems]
The present invention employs the following means in order to solve the above problems.
That is, the water stop method for the joint portion between rings in the widened segment according to claim 1 is the widened segment when the movable portion of the widened segment is moved outward in the radial direction of the tunnel so as to project to the pre-excavated surplus portion. A method for water-stopping a joint portion between rings in a widened segment that connects the two, wherein the main beam of the movable part of one widened segment and the main beam of the movable part of the other widened segment of two adjacent widened segments A step of unfastening the fastening means for connecting these through the coaxial fastening holes respectively formed in the main girders, and the fastening holes formed in the main girders of the movable part of the one widened segment with a plug member A step of closing, a step of moving the movable part of the one widened segment outward in the tunnel radial direction and projecting to the overexcavated part, and a movable part of the other widened segment The process of moving outward in the tunnel radial direction and projecting to the overexcavation part, the process of removing the plug member closing the fastening hole of the main girder of the movable part of the one widened segment, and extending to the overexcavation part together A step of fastening the main girders of the movable portions of the two widened segments that have been taken out again with the fastening means.
In this case, when moving the movable part of the widened segment outward in the tunnel radial direction, the fastening hole is previously closed with a plug member, so that groundwater, earth and sand, etc. enter the widened segment from the fastening hole of the movable part. Can be prevented.
[0008]
The water stoppage method for the joint part between rings in the widened segment according to claim 2 is the method according to claim 1, wherein the fastening means is a bolt member and a nut member, and is formed in the main beam of the movable part of the widened segment. The fastening hole thus formed is a bolt insertion hole.
In this case, since the fastening is performed by a bolt member and a nut member that have many examples of use and high reliability, the soundness of the joint portion can be improved and the cost can be reduced.
[0009]
The water stopping method for the inter-ring joint portion in the widened segment according to claim 3 is the method according to claim 1 or 2, wherein the end of the plug member is connected to the outer surface of the main beam of the movable portion of the one widened segment. It is characterized by being installed to be flush with each other.
In this case, since the tip of the plug member is flush with the outer surface of the main girder, for example, even when a sealing material is interposed between the joining surfaces of the main beams of adjacent widened segments, The seal member is not damaged.
[0010]
The water stop structure of the joint portion between the rings in the widened segment according to claim 4 is moved between the movable portions of adjacent widened segments that are moved outward in the radial direction of the tunnel so as to project to the pre-excavated surplus part. A water stop structure for a joint portion between rings in a widened segment that is connected by inserting a bolt into a coaxial fastening hole formed in a main beam of each movable portion of the widened segment, A cylindrical member attached to the inner surface of the main beam of the movable part of one of the widened segments coaxially with a fastening hole formed in the main beam and capable of mounting a plug member closing the fastening hole; and the cylinder A bolt member that is inserted into the member and has a tip inserted through the fastening holes formed in the main beams of the movable portions of the adjacent widened segments; and the two adjacent widened segments And a nut member which is screwed to the distal end portion of the bolt member from the inner surface side of the main girder, characterized in that it comprises a by the movable portion of the other widening segment of.
In this case, since the cylindrical member is provided on the inner surface of the main beam of the movable part of one widened segment, when the movable part of the widened segment is moved outward in the tunnel radial direction, the widening is performed using this cylindrical member. The tip negative material can be mounted so as to block the bolt insertion hole of the movable part of the segment, and the method according to claim 1 described above can be suitably implemented.
[0011]
The water stop structure of the inter-ring joint portion in the widened segment according to claim 5 is the one according to claim 4, wherein the nut member is within the main beam of the other widened segment of the two adjacent widened segments. It is characterized by being attached to the side surface coaxially and rotatably with the fastening hole formed in the main girder by a holder.
In this case, since the nut member is rotatably attached, when moving the movable portion of the widened segment outward in the tunnel radial direction, the fastening with the bolt member can be easily released and the fastening with the bolt member Even when unraveled, since it remains attached to the movable part of the widened segment, management of the nut member is facilitated.
[0012]
The water stop structure of the inter-ring joint portion in the widened segment according to claim 6 is the one according to claim 5, wherein the nut member has a bag shape having a bottom portion, and the other widened segment of the widened segments. It is characterized in that it is liquid-tightly attached to the inner side surface of the main beam of the movable part via a seal member.
In this case, since the bag-shaped nut member is used and the seal member is interposed between the nut member and the main beam of the movable part of the widened segment, the movable part of one or the other widened segment is moved. When this is done, the bolt insertion hole on the side to which the nut member is attached is kept fluid-tight, thereby preventing infiltration of groundwater and earth and sand from the bolt insertion hole.
[0013]
The water stop structure of the joint portion between rings in the widened segment according to claim 7 is the one according to claim 5 or 6, wherein the nut member is inserted into the fastening hole of the main beam of the movable portion of the other widened segment. A cylindrical portion through which the bolt member is inserted is formed inside.
In this case, even if the widened segment combined in a ring shape is deformed or displaced due to the influence of ground pressure, etc., even if it is difficult to remove the bolt member and nut member once tightened, The fastening between the member and the nut member can be released.
[0014]
The water stop structure of the joint between rings in the widened segment according to claim 8 is the structure according to claim 4, wherein the main end of the main beam of the movable part of the other widened segment is provided at the inner end of the fastening hole. A cylindrical body made of a material softer than the girder material and having a bolt insertion hole smaller in diameter than the fastening hole is attached.
Also in this case, since the cylindrical body set in the fastening hole is easily deformed, similarly to the seventh aspect, the fastening between the bolt member and the nut member can be easily released.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention shown in the drawings will be described.
<First Embodiment of the Invention>
1 to 9 show a first embodiment of the invention.
FIG. 1 is a diagram illustrating a situation where a shield excavator 1 excavates a tunnel 3 having a widening pit 2. As shown in FIG. 1, the shield excavator 1 includes an excavator body 4, an excavation cutter 5, a copy cutter 6, and the like.
[0016]
The excavation cutter 5 is provided on the end surface of the tubular excavator body 4. The copy cutter 6 is provided as a part of the excavation cutter 5, for example, and is configured to be extended to the side of the shield excavator 1 as necessary. Further, the excavation cutter 5 is slidable in the circumferential direction of the excavator body 4 by a face plate slide mechanism.
[0017]
FIG. 1 (a) shows a situation where the normal mine 9 of the tunnel 3 is excavated. The normal mine 9 is a part having a normal circumferential cross section in a mine excavated to construct the tunnel 3. As shown in FIG. 1A, the shield excavator 1 excavates the natural ground 10 in a state where the copy cutter 6 is stored in the excavation cutter 5, thereby forming the normal pit 9 of the tunnel 3. In the rear part of the excavator body 4, the segment 11 is installed inside the normal mine 9.
[0018]
FIG. 1B shows a state where the widening pit 2 of the tunnel 3 is excavated. FIG. 2 shows a cross section taken along line XX in FIG. The widening pit 2 is a portion of the mine excavated to construct the tunnel 3 and whose circumferential cross section is wider than that of the normal pit 9. As shown in FIGS. 1 (b) and 2, the excavator body 4 is formed on the outer side of 4.
[0019]
As shown in FIG. 1B, the shield excavator 1 extends the copy cutter 6 outward in the radial direction of the excavation cutter 5 and excavates the normal section with the excavation cutter 5, while The digging portion 12 is excavated to form the widening pit 2 of the tunnel 3. In addition, according to the width | variety of the surplus digging part 12 to excavate, you may excavate the surplus digging part 12 using the copy cutter 6 and a face plate slide mechanism together.
In addition, the surplus digging part 12 between the inner wall of the widening pit 2 and the excavator main body 4 is filled with a filler as necessary.
[0020]
In the rear part of the excavator body 4, an adjustment segment ring 14 having an adjustment segment 13 is installed on the inner wall of the normal mine 9 at the boundary with the normal mine 9 widening mine 2 as necessary.
[0021]
The adjustment segment 13 of the adjustment segment ring 14 is installed adjacent to the widening segment 17 of the widening segment ring 16. The adjusting segment 13 is a member for smoothly connecting the segment ring 11 and the widened segment 15 of the normal well 9. As shown in FIG. 1C, the inner peripheral surface of the adjusting segment 13 has a gradient from the inner peripheral surface of the segment 11 of the normal well 9 toward the inner peripheral surface of the widened segment 17.
[0022]
FIG. 1C shows a situation where the widening segment ring 16 is installed. As shown in FIG. 1C, the natural ground 10 is further excavated from the state shown in FIG. 1B, and the widening segment ring 16 having the widening segment 17 is installed at the rear part of the excavator body 4.
[0023]
FIG. 3 is a perspective view schematically showing the widening segment ring 16. As shown in FIGS. 4 and 5, the widening segment ring 16 includes a segment 18 that is the same as the segment installed in the normal well 9 and a widening segment 17 having a widening member 20 on the inner peripheral surface side. . The widened segment 17 is composed of a movable portion 17A that can move radially outward of the widening segment ring 16 and a fixed portion 17B that does not move.
Further, a hinge portion 21 is provided between the movable portion 17A and the fixed portion 17B of the widened segment 17 so as to allow movement of the movable portion 17A.
[0024]
As shown in FIG. 1C, the widening segment ring 16 is installed inside the overexcavated portion 12. At this time, the widening segment ring 16 is in the state shown in FIG. 3, and the outer diameter of the widening segment ring 16 is the same as the outer diameter of the segment ring or the adjusting segment ring 14 installed in the normal well 9. .
[0025]
In the state shown in FIG. 1C, normal segment rings adjacent to each other in the axial direction of the tunnel 3 are connected to each other by a fastening means having an inter-ring joint portion made of, for example, a bolt member and a nut member. Adjacent widened segment rings 16 are connected to each other by the fastening means in the same manner as described above.
However, the inter-ring joint between the movable portions 17A of the widened segments 17 among the adjacent widened segment rings 16 exhibits a water stop function so that groundwater or the like does not enter the segment even when the movable portion 17A moves. It has a special structure that can be done.
[0026]
This water stop structure will be described. FIG. 6 is an enlarged view of a portion indicated by Y in FIG. In FIG. 6, reference numeral 30 denotes a skin plate of the movable part 17 A of one widened segment among adjacent widened segments, reference numeral 31 denotes a main girder of the movable part 17 A of one widened segment, and reference numeral 32 denotes the other of the adjacent widened segments 17. The skin plate of the movable part 17A of the widened segment, reference numeral 33 is the main beam of the movable part 17A of the other widened segment. Bolt insertion holes 34 through which fastening bolt members are respectively inserted are formed at predetermined positions of the main girders 31 and 33.
[0027]
A cylindrical member 35 is attached to the inner side surface of the main beam 31 of the movable portion 17A of one widened segment 17 coaxially with the bolt insertion hole 34 by, for example, welding. The cylindrical member 35 is for mounting a plug member 50 to be described later for liquid-tightly closing the bolt insertion hole 34 of the main beam 31 of one widened segment 17 in a later process.
The cylindrical member 35 includes a small-diameter portion 36 on the main girder side whose inner diameter is larger than that of the bolt insertion hole, and a large-diameter portion on the opposite side to the main girder side whose inner diameter is larger than that of the small-diameter portion 36. 37. The large diameter portion 37 is formed in a tapered shape so as to gradually increase in diameter toward the outside, and a female screw portion 38 is formed on the inner periphery.
[0028]
A bolt member 39 is inserted into the cylindrical member 35. The bolt member 39 is inserted into a bolt insertion hole 34 formed in each of the main beams 31 and 33 of the widening segment whose tip is adjacent to the other widening segment. The main girder 33 protrudes inside.
[0029]
On the other hand, a nut member 40 is attached to the inner side surface of the main girder 33 of the movable portion 17A of the other widened segment 17 of the two adjacent widened segments 17, and the nut member 40 is attached to the tip of the bolt member 39. Screwed together.
As described above, the nut member 40 is screwed to the front end of the bolt member 39 inserted into the bolt insertion hole 34 and is strongly fastened, so that the main girders 31 and 33 of the movable portions 17A of the two adjacent widened segments 17 are connected to each other. Are concatenated. That is, the bolt member 39 and the nut member 40 constitute a fastening means T for the inter-ring joint portion of the widened segment.
[0030]
The nut member 40 is formed in a bag shape having a bottom portion 41, and a flange portion 42 is formed on the inner surface side of the main beam 33 of the other widened segment. This flange portion 42 is shown in FIG. In this manner, the ring is fitted into the holder 43 including the split rings 43a and 43a. The holder 43 is attached to the inner surface of the main girder 33 by fixing means such as welding, so that the nut member 40 is coaxially supported in the bolt insertion hole 34 of the main girder 33 and is rotatably supported. Is done.
[0031]
A cylindrical portion 44 is formed on the flange portion 42 side of the nut member 40 so as to protrude further outward than the flange portion 42. The cylindrical portion 44 is inserted into the bolt insertion hole 34 of the main girder 33 of the other widened segment 17, and the bolt member 39 is inserted therein with some play. Further, an internal thread is formed on the inner peripheral surface of the cylindrical portion 44 as necessary.
[0032]
Further, a seal member 45 fitted in a ring groove 40a formed in the nut member 40 is interposed between the nut member 40 and the main beam 33, whereby the nut member 40 and the main beam 33 are separated from each other. It is kept liquid-tight.
[0033]
As described above, the movable portion 17A of the widened segment 17 before widening is connected to each other by the bolt member 39 and the nut member 40. Thereafter, when the shield excavator 1 advances forward by a predetermined distance, the widened segment 17 is moved forward. The bolt member 39 and the nut member 40 are unfastened in advance when the movable portion 17A of the movable portion 17A is moved outwardly in the tunnel radial direction so as to project to the overexcavated portion 12 and widened.
[0034]
That is, when the nut member 40 is rotated in the direction opposite to the fastening direction, the screw alignment with the bolt member 39 is released (see FIG. 6B).
[0035]
In this case, the widened segments 17 combined in a ring shape are deformed or displaced due to, for example, the influence of ground pressure, and the bolt insertion holes 34 of the main girders 31 and 33 of the adjacent widened segments 17 are displaced from the coaxial shape. Even when the bolt member 39 and the nut member 40 that are fastened are unlikely to come off, the cylindrical portion 44 is provided integrally with the nut member 39, and the bolt member 39 is directly connected to the bolt insertion hole 34 of the main girder 33. Therefore, the bolt member 39 and the nut member 40 can be easily unfastened.
[0036]
Further, since the nut member 40 is rotatably attached by the holder 43, the fastening with the bolt member 39 can be easily released only by rotating the nut member 40, and even after the nut member 40 is removed. Since the nut member 40 can maintain the state attached to the main girder 33, the management of the nut member 40 becomes easy.
[0037]
Next, the bolt insertion hole 34 formed in the main beam 31 of the one widened segment 17 from which the bolt member 39 has been removed is closed with the plug member 50. The plug member 50 includes a plug body 51 inserted into the bolt insertion hole 34 and a large-diameter head 52 inserted into the small-diameter portion 36 of the cylindrical member 35 as shown in FIGS. The large-diameter head portion 52 is fixed by being pressed from the inside of the widened segment 17 by a retaining member 53 screwed into the large-diameter portion of the cylindrical member 35.
[0038]
Here, as shown in FIG. 6C, the tip of the plug member 50 is installed so as to be flush with the outer surface of the 17 main girder 31 of one widened segment.
[0039]
Thereafter, a jack (not shown) is set in the widened segment ring 16, and by operating this jack, the movable portion 17A of one widened segment 17 is moved outwardly in the tunnel radial direction to project to the overexcavated portion 12. (See FIG. 5).
[0040]
In this case, since the bolt insertion hole 34 of the movable portion 17A of the one widened segment 17 is closed with the plug member 50 in advance, groundwater, earth and sand, etc. enter the widened segment from the bolt insertion hole 34 of the movable portion 17A. Can be prevented.
In addition, since the tip of the plug member 50 is flush with the outer surface of the main girder 31, for example, when the sealing member 54 is interposed between the joint surfaces of the main beams 31 and 33 of the adjacent widened segments 17 Even so, the seal member 54 is not damaged (see FIG. 5).
Incidentally, when the distal end of the plug member 50 is located behind the bolt insertion hole 34 of the main girder 31, when the movable portion 17A of the widened segment 17 is moved, the exposed edge portion of the outer edge of the bolt insertion hole 34 is exposed. As a result, the seal member 54 may be damaged.
In the above description, the distal end of the plug member 50 is flush with the outer surface of the main girder 31, but instead, as shown by the two-dot chain line in FIGS. A taper portion 34a that expands toward the main girder 33 side is provided on the outer edge of the bolt insertion hole 34 of the girder 31, and the end of the plug member 50 is set so as to reach a position on the back side of the taper portion 34a. Also good.
By providing the tapered portion 34a in the bolt insertion hole 34 of the main girder 31 in this way, for example, even when a burr occurs on the outer edge of the bolt insertion hole 34 during processing, the burr can move the movable portion of the one widened segment 17. It is possible to prevent the seal member 54 from being damaged when the 17A is moved outward in the radial direction of the tunnel.
[0041]
Next, the movable portion 17 A of the other widened segment 17 is also moved outward in the tunnel radial direction so as to project to the overexcavated portion 12.
In this case, since the bag member is used as the nut member 40 and the seal member 45 is interposed between the nut member 40 and the main beam 33 of the widened segment 17, one or the other widened segment 17 is used. When the movable portion 17A is moved, the bolt insertion hole 34 of the main girder 33 on the side to which the nut member 40 is attached can be kept liquid-tight, and thereby the side on which the nut member 40 is hung. It is possible to prevent groundwater and earth and sand from entering the segment through the bolt insertion hole 34.
[0042]
Next, the plug member 50 that has blocked the bolt insertion hole 34 of the main girder 31 of the movable portion 17 A of the one widened segment 17 is removed by loosening the screwing of the retaining member 53. At this time, if necessary, the jig is engaged with the screw portion 52a formed on the large-diameter head portion 52 of the plug member 50 and removed.
[0043]
Thereafter, the main girders 31 and 33 of the movable portions 17A of the two adjacent widened segments 17 both projecting to the overexcavated portion 12 are fastened again using the bolt member 39 and the nut member 40 (FIG. 6 ( a)).
Proceed through the tunnel as described above.
[0044]
In the case of the nut member 40 shown in FIGS. 6A and 7, the nut member 40 is provided with the cylindrical portion 44, but the widened segment 17 itself once combined is less deformed, and the bolt member and the nut member are used. As shown in FIG. 8, a nut member 55 that does not have a cylindrical portion may be used.
Furthermore, as another example of the nut member, as shown in FIG. 9, a cap nut 56 with a flange 56a can be cited, and such a nut member may be used.
[0045]
<Second Embodiment of the Invention>
FIG. 10 shows a second embodiment of the present invention.
This embodiment is an example in which there is little risk of ingress of groundwater or the like into the segment from the bolt insertion hole 34 on the side where the nut member 60 is attached due to the ground surrounding the tunnel.
Note that the same components as those shown in FIG. 6 are denoted by the same reference numerals and their section names are omitted.
[0046]
Here, a recess 60 is provided at the inner end of the bolt insertion hole 34 of the main girder 33 of the movable portion 17A of the other widened segment 17, and the recess 60 is made of a material softer than the material of the main girders 31 and 33, and A cylindrical body 61 having a bolt insertion hole 61a having a smaller diameter than the bolt insertion hole 34 is attached.
Even in this case, the widened segment 17 is deformed or displaced, the bolt insertion holes 34 of the main girders 31 and 33 are displaced from the coaxial shape, and the bolt member 39 is at the edge of the main girder 33 with the bolt insertion hole 34. A situation in which the bolt member 39 and the nut member 62 that are bitten and fastened are difficult to come off can be avoided by easily deforming the cylindrical body 61 set in the recess 60.
[0047]
The above-described embodiment is merely an example of the present invention, and the design of the present invention can be appropriately changed as necessary.
For example, in the above-described embodiment, the bolt member and the nut member are used as the fastening means for the joint portion between the rings of the movable portion 17a of the widened segment 17, but the present invention is not limited to this, and other fastening means may be used. The present invention is applicable to any fastening means that uses fastening holes.
[0048]
【The invention's effect】
As described above, according to the present invention, the movable portion is moved outward in the tunnel radial direction at the tip of the adjacent widened segments, and the fastening hole of the main beam of the movable portion of one widened segment is plugged. Therefore, it is possible to prevent intrusion of groundwater, earth and sand, etc., into the widened segment from the fastening hole of the main girder of the movable part.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a state of excavating a tunnel with a shield excavator according to a first embodiment of the present invention.
FIG. 2 is a cross-sectional view taken along line XX in FIG.
FIG. 3 is a schematic perspective view of a widened segment ring.
FIG. 4 shows a widened segment and is a side view before moving a movable part.
FIG. 5 shows a widened segment, and is a side view after moving a movable part.
FIG. 6 is a cross-sectional view showing a structure of a joint part between rings of a main girder of a movable part of a widening segment.
FIG. 7 is a perspective view showing a structure of a ring-to-ring joint portion of a main girder of a movable portion of a widening segment.
FIG. 8 is a perspective view showing a modification of the nut member.
FIG. 9 is a perspective view showing another modification of the nut member.
FIG. 10 is a cross-sectional view showing a structure of an inter-ring joint portion of a main girder of a movable portion of a widening fragment according to a second embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Shield excavator 2 Tunnel 16 Widening segment ring 17 Widening segment 17A Movable part 17B Fixed part 31, 33 Main beam 34 Bolt insertion hole (fastening hole)
35 cylindrical member 39 bolt member 40 nut member 41 bottom portion 42 flange portion 43 holder 44 cylindrical portion 45 sealing member 50 plug member 51 plug body 52 large diameter head 53 retaining member 61 cylindrical body 62 nut member T fastening means

Claims

A water stop method for a joint portion between rings in a widened segment, which connects the widened segments when moving the movable part of the widened segment outward in the radial direction of the tunnel so as to project to the pre-excavated excavated portion,
The main girder of the movable part of one widened segment and the main girder of the movable part of the other widened segment of two adjacent widened segments are connected via coaxial fastening holes respectively formed in these main girders. A step of unfastening the fastening means;
Plugging a fastening hole formed in the main beam of the movable part of the one widened segment with a plug member;
A step of moving the movable portion of the one widened segment outward in the tunnel radial direction and projecting to the surplus digging portion;
A step of moving the movable portion of the other widened segment outward in the tunnel radial direction and projecting to the surplus digging portion;
Removing the plug member closing the fastening hole of the main beam of the movable part of the one widened segment;
And a step of fastening the main girders of the movable portions of the two widened segments, both of which are extended to the overexcavated portion, with the fastening means again.

In the water stop method of the joint part between rings in the widening segment according to claim 1,
The fastening means is a bolt member and a nut member, and the fastening hole formed in the main girder of the movable part of the widened segment is a bolt insertion hole. Method.

In the water stop method of the joint part between rings in the widening segment of Claim 1 or 2,
A water stop method for a joint part between rings in a widened segment, wherein the end of the plug member is installed so as to be flush with an outer surface of a main beam of a movable part of the one widened segment.

Coaxial fastening formed between the movable parts of adjacent widened segments that are moved outward in the radial direction of the tunnel so as to project to the pre-excavated overexcavated part, respectively, on the main beam of the movable part of the widened segment. A water stop structure of a joint portion between rings in a widened segment that is connected by inserting a bolt into a hole,
A plug member is mounted on the inner surface of the main beam of the movable part of one of the adjacent two widened segments so as to be coaxial with the fastening hole formed in the main beam and close the fastening hole. Possible cylindrical members;
A bolt member that is inserted into the cylindrical member and has the tip inserted through the fastening holes formed in the main beams of the movable portions of the adjacent widened segments; and
A nut member screwed onto the tip of the bolt member from the inner surface side of the main beam of the movable portion of the other widened segment of the two adjacent widened segments;
The water stop structure of the joint part between rings in the widening segment characterized by comprising.

In the water stop structure of the joint part between rings in the widened segment according to claim 4,
The nut member is coaxially and rotatably attached to the fastening hole formed in the main beam by a holder on the inner surface of the main beam of the other widened segment of the two adjacent widened segments. The water stop structure of the joint part between rings in the widening segment characterized by this.

In the water stop structure of the joint part between rings in the widened segment according to claim 5,
The nut member has a bag shape having a bottom portion, and is liquid-tightly attached to the inner side surface of the main beam of the movable portion of the other widened segment among the widened segments via a seal member. The water stop structure of the joint part between rings in the widening segment.

In the water stop structure of the joint part between rings in the widened segment according to claim 5 or 6,
An inter-ring joint in a widened segment, wherein the nut member is formed with a cylindrical portion that is inserted into a fastening hole of a main girder of a movable portion of the other widened segment and into which the bolt member is inserted. Water stop structure of the part.

In the water stop structure of the joint part between rings in the widened segment according to claim 4,
A cylindrical body having a bolt insertion hole made of a material softer than the material of the main girder and having a smaller diameter than the fastening hole is formed at the inner end portion of the main girder of the movable part of the other widened segment. The water stop structure of the joint part between rings in the widening segment characterized by being attached.