JP3921380B2

JP3921380B2 - Construction method of underground structure and its reinforcement structure

Info

Publication number: JP3921380B2
Application number: JP2001346146A
Authority: JP
Inventors: 良幸濱田; 覚田村; 和義佐藤; 明俊 ▲鶴▼見
Original assignee: JFE Metal Products and Engineering Inc; Kato Construction Co Ltd
Current assignee: JFE Metal Products and Engineering Inc; Kato Construction Co Ltd
Priority date: 2001-11-12
Filing date: 2001-11-12
Publication date: 2007-05-30
Anticipated expiration: 2021-11-12
Also published as: JP2003148082A

Description

【０００１】
【発明の属する技術分野】
本発明は、地下沈設構造物の構築方法とその補強構造に関し、特にリング状沈設体である複数の圧入リングを順次地中に圧入沈設しながら積み上げて立坑等の地下沈設構造物を構築するにあたり、構築後にその沈設構造物の側壁の一部に形成されることになる開口部を補強するのに好適な構築方法と補強構造に関する。
【０００２】
【従来の技術と発明が解決しようとする課題】
リング状沈設体を圧入工法によって積み上げて立坑を構築した後に管路接合等のためのその立坑の側壁の一部に開口部を形成する場合、開口に伴う欠損箇所の補強を目的として二次工程としてその開口部相当部の周囲に補強材を配置することが行われる。例えば、地下沈設構造物からなる立坑を構築したならば、その立坑の内側において開口部となる部位の周囲を取り囲むように縦横にＨ鋼を建て込み、そのＨ鋼を梁部材として開口部に加わる荷重を受け持つための補強構造とすることが行われる。
【０００３】
この構造では、Ｈ鋼が立坑内部に張り出すことからその立坑の有効内径寸法が制約されるほか、Ｈ鋼の設置作業が坑内での作業となるために作業性が悪く、工期も長くならざるを得ない。
【０００４】
このようなことから、例えば特開２０００−１７０１７０号公報に記載されているように、複数のセグメントピースを組み合わせてなる複数の圧入リングを順次圧入沈設しながら積み上げる際に、開口部の下側を補強する補強ピースを含む下側水平補強リングを沈設するとともに、その上に開口部の両側を補強する補強ピースを含む垂直補強リングを沈設し、さらにその上に下側水平補強リングと同様の上側水平補強リングを沈設して、最後に各補強ピースを貫通するように鉄筋を組み込んだ上でコンクリートを打ち込み、実質的に沈設構造物が構築される過程で同時に開口部の補強構造を構築するようにした技術が提案されている。
【０００５】
この方法では、コンクリートの打ち込みが必須であることから、作業工数が多いばかりでなく養生期間を必要とし、工期も長くなることとなって好ましくない。
【０００６】
本発明は以上のような課題に着目してなされたもので、コンクリートの打ち込みを必要とすることなく、地下沈設構造物が構築される過程で同時に開口部の補強構造を構築できるようにした地下沈設構造物の構築方法と補強構造を提供しようとするものである。
【０００７】
【課題を解決するための手段】
請求項１に記載の発明は、圧入リングを順次地中に圧入沈設しつつその圧入リングを多段にわたり積み重ねることにより筒状壁体として構築されるとともに、構築後に側壁の一部に複数段の圧入リングにまたがるようにして開口部が形成される地下沈設構造物を構築する方法を前提として、上記開口部相当位置の両側に位置することになる部位に縦梁用凹部が予め形成されていて且つその開口部相当位置の下側を補強することになる開口部下側補強リングを圧入沈設する工程と、上記開口部相当位置の両側に位置することになる部位に縦梁用凹部が予め形成された開口部リングについて、その縦梁用凹部の位置を開口部下側補強リング側のものと整合させながら上記開口部の形成に関与する段数分だけ上記開口部下側補強リングの上に順次圧入沈設しながら積み重ねる工程と、上記開口部相当位置の両側に位置することになる部位に縦梁用凹部が予め形成されていて且つその開口部相当位置の上側を補強することになる開口部上側補強リングについて、その縦梁用凹部の位置を開口部リング側のものと整合させながら上記開口部リングの上に圧入沈設する工程と、上記縦梁用凹部同士の整合をもって形成された縦梁収容空間に対し、これと整合合致するように上記開口部下側補強リングと複数段の開口部リングおよび開口部上側補強リングにまたがる長さの縦梁を各リングの内側から組み込んで補強する工程と、を含むことを特徴としている。
【０００８】
また、請求項２に記載の発明は、請求項１に記載の発明を実質的に補強構造としてとらえたものであり、圧入リングを順次地中に圧入沈設しつつその圧入リングを多段にわたり積み重ねることにより筒状壁体として構築されるとともに、構築後に側壁の一部に複数段の圧入リングにまたがるようにして開口部が形成される地下沈設構造物の補強構造であって、上記開口部相当位置の両側に位置することになる部位に縦梁用凹部が予め形成されていて且つその開口部相当位置の下側を補強することになる開口部下側補強リングと、上記開口部相当位置の両側に位置することになる部位に縦梁用凹部が予め形成されていて、その縦梁用凹部の位置が開口部下側補強リング側のものと整合するように該開口部下側補強リングの上に上記開口部の形成に関与する段数分だけ順次積み重ねられた複数段の開口部リングと、上記開口部相当位置の両側に位置することになる部位に縦梁用凹部が予め形成されていて、その縦梁用凹部の位置が開口部リング側のものと整合するように該開口部リングの上に配置されることによりその開口部相当位置の上側を補強することになる開口部上側補強リングと、を備えている。
【０００９】
そして、上記縦梁用凹部同士の整合をもって形成された縦梁収容空間に対し、これと整合合致するように上記開口部下側補強リングと複数段の開口部リングおよび開口部上側補強リングにまたがる長さの縦梁を各リングの内側から組み込んで補強したことを特徴としている。
【００１０】
ここで、上記開口部リング自体が開口部下側補強リングおよび開口部上側補強リングと同等の強度を有している場合は別として、上記開口部下側補強リングと開口部上側補強リングはその機能よりして特に開口部リングよりも水平方向での耐圧強度が高められていることが望ましい。また、上記縦梁収容空間に組み込まれた縦梁はその全周において地下沈設構造物と溶接接合される。
【００１１】
したがって、この請求項１，２に記載の発明では、必要数の圧入リングを積み上げる過程で縦梁収容空間が形成されることから、その必要数の圧入リングの積み上げが完了した時点で、縦梁収容空間に整合合致するようにその複数段の圧入リングにまたがる長さの縦梁を該圧入リングの内側から組み込むことにより、この縦梁と開口部下側補強リングおよび開口部上側補強リングをもって上記開口部の補強構造が構築される。
【００１２】
請求項３に記載の発明は、請求項２の記載を前提として、上記開口部下側補強リングと開口部リングおよび開口部上側補強リングは、いずれも複数の鋼製セグメントを互いに連結することによりリング状のものとして形成されていて、上記縦梁用凹部では、隣接する一般部の鋼製セグメント同士の間に、縦梁外周長と同等の内周長を有する厚みの薄い鋼製セグメントをそれに隣接し且つ一般部の鋼製セグメントとは一端部の形状が異なる鋼製セグメントとともに挟み込んで連結することにより凹状に形成されているとともに、各リングの内側からの縦梁の組み込みを可能にするためにその縦梁用凹部の開口側の周長は奧部側の周長と同一もしくはそれよりも大きく形成されていることを特徴としている。
【００１３】
また、請求項４に記載の発明は、請求項３の記載を前提として、上記縦梁用凹部同士の整合をもって形成された縦梁収容空間に縦梁を組み込んだ状態では、その縦梁の内周面が各リングの内周面とほぼ同一面をなすように設定されていることを特徴としている。
【００１４】
したがって、これらの請求項３，４に記載の発明では、地上にて複数の鋼製セグメントをもって各リングを組み立てた上で、これを順次地中に圧入沈設することで地下沈設構造物が構築される。
【００１５】
ここで、縦梁用凹部の円周方向での両側面が例えば各リングの軸心を指向するような平面をもって形成されていると、その縦梁用凹部の開口側の周長は奧部側の周長よりも小さくなって、各リングの内側から縦梁収容空間に向けてそれに整合合致する縦梁を組み込むことが不可能となる。そこで、請求項３に記載の発明では、各リングの内側からの縦梁の組み込みを可能にするためにその縦梁用凹部の開口側の周長は奧部側の周長と同一もしくはそれよりも大きく形成されていることを条件としている。
【００１６】
同時に、縦梁が各リングの内側に張り出すとそれらの各リングをもって構築された地下沈設構造物の有効内径寸法が制約されることとなって好ましくないので、これを回避するために、請求項４に記載の発明では、上記縦梁用凹部同士の整合をもって形成された縦梁収容空間に縦梁を組み込んだ状態では、その縦梁の内周面が補強用沈設体の内周面とほぼ同一面をなすように設定されていることを条件としている。
【００１７】
請求項５に記載の発明は、請求項３または４の記載を前提として、上記鋼製セグメントは、周方向に延在する少なくとも上下一対の主桁と、これらの主桁の両端部同士を連結する左右一対の継手板と、この継手板と同方向に延在する複数の縦リブおよび外側表層部として機能するスキンプレートとから形成されている一方、上記縦梁は、少なくとも上下一対の主桁と、これらの主桁の両端部同士を連結する左右一対の側板、およびこの側板と同方向に延在する複数の縦リブとから形成されていることを特徴としている。
【００１８】
すなわち、縦梁は、縦梁用凹部同士の整合をもって形成された縦梁収容空間にこれと重なり合うようにして収容されることから、請求項５に記載の発明では少なくとも縦梁についてはスキンプレートを必要としないことを明確化している。
【００１９】
【発明の効果】
請求項１，２に記載の発明によれば、必要数の圧入リングの積み上げをもって形成された縦梁収容空間に縦梁を組み込むだけで開口部の補強構造が構築されることから、従来のような鉄筋の配置やコンクリートの打ち込み、さらにはそれに伴う養生期間も不要となり、工数削減と工期短縮に大きく貢献できる利点がある。
【００２０】
請求項３に記載の発明によれば、複数の鋼製セグメントを互いに連結することにより各リングが形成されることから、地上にてリングを組み立てながらこれを地中に順次圧入沈設することができるようになり、その作業性，取り扱い性が一段と良好なものとなるほか、縦梁は縦梁収容空間に対して各リングの内側から組み込むことができるので、その組み込み作業性もきわめて良好なものとなる。
【００２１】
請求項４に記載の発明によれば、縦梁を縦梁収容空間に組み込んだ状態ではその縦梁の内周面が各リングの内周面とほぼ同一面をなすように設定されていることから、構築された地下沈設構造物の有効内径寸法が縦梁の配置によって制約されることがない。
【００２２】
【発明の実施の形態】
図１，２は発明の好ましい実施の形態を示す図であり、鋼製セグメント圧入工法によって構築された地下沈設構造物（以下、単に沈設構造物という）１の概略構造を示している。
【００２３】
同図に示すように、沈設構造物１は、リング状沈設体としての短円筒状の圧入リング２，２…を順次圧入沈設させながら鉛直方向に多数段にわたって積み重ねて、図示外のボルトとナットにて相互に締結することによって、例えば直径に比してその深さが数倍程度大きな筒状壁体として構成される。また、各圧入リング２，２…は後述するように円周方向において円弧状をなす複数の鋼製セグメントに分割されていて、予めボルトとナットとを用いて鋼製セグメント同士を締結することにより上記圧入リング２，２…として組み立てられる。
【００２４】
そして、上記沈設構造物１の構築後に、例えば他の管路３との接続のために複数の圧入リング２，２…にまたがるようにしてその一部を切除することにより円形の開口部４を形成することになるが、本実施の形態では、その開口形成に先立って、開口部４となるべき部位をその上下左右から取り囲むようにして枠状の補強構造部（図１，３において斜線を付した部分）５を上記沈設構造物１の構築段階で同時に形成する。なお、上記開口部４は構築後の沈設構造物１の内側から溶断等によって形成される。
【００２５】
本実施の形態では、圧入リング２，２…として、上部側複数段の一般部リング２Ａ，２Ａ…のほか、後から開口部４が形成されることになる同じく複数段の開口部リング２Ｂ，２Ｂ…と、開口部４が形成される部位の下段側および上段側にそれぞれ位置してこれを補強することになる開口部下側補強リング２Ｃおよび開口部上側補強リング２Ｄと、最も下段の刃口リング２Ｅとを併用するものとし、さらに上記開口部下側補強リング２Ｃから開口部上側補強リング２Ｄにまたがるようにして後から組み込まれる左右一対の縦梁６を併用するものとする。これら開口部下側補強リング２Ｃと開口部上側補強リング２Ｄおよび縦梁６は上記の枠状の補強構造部５を形成することになる。
【００２６】
上記沈設構造物１の構築のための施工手順としては、図１に示すように刃口７を備えた最下段の刃口リング２Ｅを施工場所の地表面Ｇに据え付けるとともに、その上に開口部下側補強リング２Ｃを積み上げて中間組立体とし、図示しない油圧式の圧入装置を用いてこの中間組立体を地中に圧入沈設する。そして、圧入後に例えばバケット系掘削機等を用いて中間組立体の内部の土砂を掘削する。
【００２７】
続いて、上記中間組立体の上に一段もしくは二段の開口部リング２Ｂを積み上げて中間組立体としてのリング段数を増やし、上記と同様に増やしたリング段数分だけ再度圧入沈設した上で、その中間組立体の内部の土砂を掘削する。そして、このような一段もしくは複数段の圧入リング２の積み上げと地中への圧入沈設および内部掘削とを順次繰り返すことにより図１に示したような沈設構造物１が構築される。
【００２８】
ここで、上記一般部リング２Ａ，２Ａ…は、図３，４に示すように六等分された円弧状の鋼製セグメント１２，１２…同士を突き合わせてボルトとナットとで相互に締結することにより構成され、これら一般部リング２Ａ，２Ａ…の積み上げの際には、図１に示すように鋼製セグメント１２，１２…同士の突き合わせ部の位相が上下段でずれるように交互に配置するものとする。そして、上記一般部リング２Ａを構成することになる個々の鋼製セグメント１２，１２…は、図５に示すように、上下一対の主桁１３，１３と左右一対の継手板１４，１４のほかその継手板１４，１４と平行に配置される断面略Ｌ字状の複数の縦リブ１５，１５…および外表面を構成するスキンプレート１６とから構成され、上記主桁１３，１３および継手板１４，１４には相手側となる鋼製セグメントとのボルト結合のために複数のボルト穴１７が形成される。
【００２９】
一方、上記開口部下側補強リング２Ｃと開口部リング２Ｂおよび開口部上側補強リング２Ｄは基本的にはいずれも同一構造であって、図６〜８に示すように、図５と同様の四個の鋼製セグメント１２，１２…のほか一端がテーパ形状とされた左右勝手違いの一対の調整用セグメント１８，１８および同じく左右勝手違いの一対の縦梁設置用セグメント１９，１９とを互いに突き合わせてボルトとナットで相互に締結することにより、左右の縦梁用凹部２０を有したものとして構成される。そして、これらの開口部下側補強リング２Ｃと開口部リング２Ｂ，２Ｂ…および開口部上側補強リング２Ｄをそれぞれ積み上げる際には、その縦梁用凹部２０，２０…同士が互いに整合一致するように積み上げられる。同時に、各縦梁用凹部２０，２０…の内側面２０ａ，２０ａは互いに平行となるように設定されている。これは、後述するように複数の縦梁用凹部２０，２０…をもって形成される縦梁収容空間３０に対して内側から縦梁６を組み込むためには、その縦梁用凹部の２０の開口側の周長を奥部側の周長と同一もしくはそれよりも大きく形成しておく必要があるからである。
【００３０】
図７は上記調整用セグメント１８の詳細を、図８は同じく縦梁設置用セグメント１９の詳細をそれぞれ示しており、両者ともに図５に示した鋼製セグメント１２と同様に、上下一対または三枚構成の主桁２１，２１と左右一対の継手板２２，２２のほか、その継手板２２，２２と平行に配置される断面略Ｌ字状の複数の縦リブ２３，２３および外表面を構成するスキンプレート２４とから構成され、上記主桁２１，２１および継手板２２，２２には複数のボルト穴２５，２５…が形成される。
【００３１】
ただし、上記縦梁設置用セグメント１９，１９は縦梁用凹部２０を形成するものであるために、その主桁２１，２１や継手板２２，２２等の幅寸法（図８の（Ａ）の厚み寸法ａ）は他のセグメント１２，１８の半分程度に設定される。また、上記開口部下側補強リング２Ｃおよび開口部上側補強リング２Ｄを構成することになる鋼製セグメント１２，１２…や調整用セグメント１８，１８および縦梁設置用セグメント１９，１９については、その機能よりして開口部リング２Ｂ，２Ｂ…側のものと比べて特に主桁１３，２１等の板厚が大きく設定されてその強度の向上が図られている。
【００３２】
したがって、上記のように開口部下側補強リング２Ｃおよび開口部上側補強リング２Ｄとともに必要数の開口部リング２Ｂ，２Ｂ…を積み上げることにより、各リング２Ｃ，２Ｄ，２Ｂの縦梁用凹部２０，２０同士の整合一致をもって、そのリング段数分の長さを有する左右一対の縦梁収容空間３０が形成される。
【００３３】
こうして、沈設構造物１の構築過程で上記補強構造部５の一部となる開口部下側補強リング２Ｃおよび開口部上側補強リング２Ｄとともに左右一対の縦梁収容空間３０，３０が形成されたならば、図１〜３のほか図９に示すようにその縦梁収容空間３０，３０に内側からそれぞれ縦梁６を組み込んで固定する。
【００３４】
この縦梁６は、図１０に示すように複数段の主桁３１，３１…と左右一対の側板３２，３２および縦リブ３３，３３とをもって縦梁収容空間３０に合致し得る縦長のフレーム構造のものとして形成され、図１１に示すように縦梁収容空間３０に対して内側より組み込んだ上でその全周が溶接接合される。これより、上記開口部下側補強リング２Ｂと開口部上側補強リング２Ｄおよび縦梁６とをもって開口部４となるべき領域を取り囲むような補強構造部５が形成されることになる。
【００３５】
この後、上記沈設構造物１が所定深度まで沈設した段階で、複数の開口部リング２Ｂ，２Ｂ…にまたがるようにして沈設構造物１の内側から溶断等の手段をもって開口部４を形成する。この時、開口部リング２Ｂ，２Ｂ…の一部の主桁等が切断除去されることに伴いその開口部リング２Ｂ，２Ｂ…での荷重負担能力が低下することになるが、代わってその回りに予め構築される補強構造部５に本来開口部リング２Ｂ，２Ｂ…が負担すべき荷重を分散させて負担させることで強度低下を補うことができるようになる。
【００３６】
このように本実施の形態によれば、沈設構造物１を構築する過程で同時に開口部４のまわりに補強構造部５が構築されることから、従来の工法に比べて工数削減と工期の短縮を図ることができるようになる。
【図面の簡単な説明】
【図１】本発明の好ましい実施の形態を示す図で、地下沈設構造物の正面説明図。
【図２】図１のＡ−Ａ線に沿う断面図。
【図３】図１の要部拡大説明図。
【図４】図３のＢ−Ｂ線に沿う拡大断面図。
【図５】（Ａ）は図４の一般部リングを構成することになる鋼製セグメントの拡大断面図、（Ｂ）はその正面説明図。
【図６】図３のＣ−Ｃ線に沿う拡大断面図。
【図７】（Ａ）は図６の開口部リングを構成することになる調整用セグメントの拡大断面図、（Ｂ）はその正面説明図。
【図８】（Ａ）は図６の開口部リングを構成することになる縦梁設置用セグメントの拡大断面図、（Ｂ）はその正面説明図、（Ｃ）はその左側面図。
【図９】図６の状態から縦梁を組み込む際の断面説明図。
【図１０】（Ａ）は図９に示す縦梁の拡大断面説明図、（Ｂ）はその正面説明図。
【図１１】図９の状態から縦梁の組み込みが完了した状態を示す断面説明図。
【符号の説明】
１…地下沈設構造物
２…圧入リング
２Ａ…一般部リング
２Ｂ…開口部リング
２Ｃ…開口部下側補強リング
２Ｄ…開口部上側補強リング
４…開口部
５…補強構造部
６…縦梁
１２…鋼製セグメント
１３…主桁
１４…継手板
１５…縦リブ
１６…スキンプレート
１８…調整用セグメント
１９…縦梁設置用セグメント
２０…縦梁用凹部
２１…主桁
２２…継手板
２３…縦リブ
２４…スキンプレート
３０…縦梁収容空間
３１…主桁
３２…側板
３３…縦リブ[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for constructing an underground subsidence structure and a reinforcing structure thereof, and more particularly to constructing an underground subsidence structure such as a shaft by stacking a plurality of press-fitting rings, which are ring-shaped subsidences, while sequentially injecting and subsiding into the ground. The present invention relates to a construction method and a reinforcement structure suitable for reinforcing an opening which is to be formed in a part of the side wall of the subsidence structure after construction.
[0002]
[Prior art and problems to be solved by the invention]
When an opening is formed in a part of the side wall of a shaft for pipe jointing etc. after building a shaft by stacking ring-shaped structures by the press-fitting method, a secondary process for the purpose of reinforcing the missing part accompanying the opening As described above, a reinforcing material is disposed around the opening equivalent portion. For example, if a shaft made of an underground subsidence structure is constructed, H steel is built vertically and horizontally so as to surround the periphery of the portion that becomes the opening inside the shaft, and the H steel is added to the opening as a beam member. Reinforcing structures for handling loads are performed.
[0003]
In this structure, since the H steel projects into the shaft, the effective inner diameter of the shaft is limited, and the installation work of the H steel is a work in the shaft, so the workability is poor and the construction period is not long. I do not get.
[0004]
For this reason, for example, as described in Japanese Patent Application Laid-Open No. 2000-170170, when stacking a plurality of press-fitting rings formed by combining a plurality of segment pieces sequentially while press-fitting, the lower side of the opening is A lower horizontal reinforcing ring including a reinforcing piece to be reinforced is sunk, a vertical reinforcing ring including reinforcing pieces to reinforce both sides of the opening is laid thereon, and an upper side similar to the lower horizontal reinforcing ring is further provided thereon. The horizontal reinforcement ring is laid down, and finally the reinforcing bars are inserted so as to penetrate through the reinforcing pieces, and then concrete is driven in, so that the reinforced structure of the opening is built at the same time as the laid structure is built. The proposed technology has been proposed.
[0005]
In this method, since it is indispensable to drive concrete, not only the number of work steps is large but also a curing period is required, and the work period becomes long, which is not preferable.
[0006]
The present invention has been made paying attention to the problems as described above, and it is possible to construct a reinforcing structure for an opening at the same time in the process of constructing an underground subsiding structure without requiring concrete driving. It is an object of the present invention to provide a method for constructing a subsidence structure and a reinforcing structure.
[0007]
[Means for Solving the Problems]
The invention according to claim 1 is constructed as a cylindrical wall body by sequentially stacking the press-fitting rings into the ground and stacking the press-fitting rings in multiple stages, and after the construction, a plurality of press-fittings are performed on a part of the side wall. On the premise of a method of constructing an underground subsidence structure in which an opening is formed so as to straddle the ring, the vertical beam recesses are formed in advance at sites that will be located on both sides of the opening equivalent position, and A step of press-fitting and sinking an opening lower reinforcing ring that reinforces the lower side of the opening equivalent position, and concave portions for the vertical beam are formed in advance at sites that will be located on both sides of the opening equivalent position. For the opening ring, the position of the concave portion for the longitudinal beam is aligned with that on the lower reinforcing ring side of the opening, and pressure is sequentially applied on the lower reinforcing ring by the number of steps involved in forming the opening. The step of stacking while being laid and the upper part reinforcement of the opening part where the concave portions for the vertical beam are formed in advance at the parts that will be located on both sides of the position corresponding to the opening part and the upper side of the position corresponding to the opening part is reinforced For the ring, the step of press-fitting on the opening ring while aligning the position of the concave portion for the vertical beam with that on the opening ring side, and the vertical beam accommodating space formed by aligning the concave portions for the vertical beam On the other hand, the step of reinforcing the above-mentioned opening lower reinforcement ring, a plurality of opening rings and a longitudinal beam extending across the opening upper reinforcement ring from the inside of each ring so as to match and reinforce It is characterized by including.
[0008]
Further, the invention according to claim 2 is the one in which the invention according to claim 1 is substantially regarded as a reinforcing structure, and the press-fitting rings are stacked in multiple stages while being sequentially press-fitted into the ground. Is constructed as a cylindrical wall body, and is a reinforcing structure for an underground substituting structure in which an opening is formed so as to straddle a plurality of press-fitting rings in a part of the side wall after construction, and the position corresponding to the opening The vertical beam recesses are formed in advance on the portions that are to be located on both sides of the opening, and the opening lower reinforcement ring that reinforces the lower side of the opening equivalent position, and both sides of the opening equivalent position. A longitudinal beam recess is pre-formed at the location to be located, and the opening above the opening lower reinforcement ring so that the position of the longitudinal beam recess aligns with that of the opening lower reinforcement ring side. Part formation A plurality of opening rings that are sequentially stacked for the number of steps involved, and vertical beam recesses are formed in advance at positions that are located on both sides of the opening equivalent position, and the position of the vertical beam recesses Are arranged on the opening ring so as to be aligned with those on the opening ring side, thereby reinforcing the upper side of the opening equivalent position.
[0009]
A length spanning the opening lower reinforcement ring, the multi-stage opening ring, and the opening upper reinforcement ring so that the vertical beam housing space formed by alignment of the recesses for the longitudinal beams is aligned and matched with the space. It is characterized by the fact that the vertical beam is incorporated and reinforced from the inside of each ring.
[0010]
Here, apart from the case where the opening ring itself has the same strength as the opening lower reinforcing ring and the opening upper reinforcing ring, the opening lower reinforcing ring and the opening upper reinforcing ring have their functions. In particular, it is desirable that the pressure strength in the horizontal direction is higher than that of the opening ring. Further, the vertical beam incorporated in the vertical beam accommodating space is welded and joined to the underground structure at the entire periphery.
[0011]
Therefore, in the inventions according to the first and second aspects, since the vertical beam housing space is formed in the process of stacking the required number of press-fitting rings, when the necessary number of press-fitting rings have been stacked, By incorporating a vertical beam having a length that spans the multiple stages of press-fitting rings from the inside of the press-fitting ring so as to be aligned and matched with the receiving space, the opening is formed with the vertical beam, the lower opening reinforcement ring, and the upper opening reinforcement ring. The reinforcement structure of the part is constructed.
[0012]
According to a third aspect of the present invention, on the premise of the second aspect, each of the opening lower reinforcing ring, the opening ring, and the opening upper reinforcing ring is formed by connecting a plurality of steel segments to each other. be formed as Jo ones, in the longitudinal beams recess, between the steel segments of the adjacent general portion, the thin steel segment thick having an inner peripheral length of the equivalent longitudinal beams outer peripheral length thereto adjacent and together with the general portion steel segments are formed into a concave shape by the shape of the end portion connecting sandwiches with different steel segments, for permitting integration of the longitudinal beams from the inside of the ring Further, the circumferential length on the opening side of the concave portion for the vertical beam is characterized by being formed to be equal to or larger than the circumferential length on the flange side.
[0013]
Further, the invention described in claim 4 is based on the premise of claim 3 and in the state where the vertical beam is incorporated in the vertical beam housing space formed by aligning the concave portions for the vertical beam, It is characterized in that the peripheral surface is set so as to be substantially flush with the inner peripheral surface of each ring.
[0014]
Therefore, in the inventions according to the third and fourth aspects of the present invention, after assembling each ring with a plurality of steel segments on the ground, this is sequentially press-fitted into the ground to construct an underground subsidence structure. The
[0015]
Here, when both side surfaces in the circumferential direction of the concave portion for the vertical beam are formed with a plane that faces the axis of each ring, for example, the circumferential length on the opening side of the concave portion for the vertical beam is the buttock side It becomes impossible to incorporate a vertical beam that is aligned and matched from the inside of each ring toward the vertical beam accommodating space. Therefore, in the invention according to claim 3, in order to enable the incorporation of the vertical beam from the inside of each ring, the circumferential length on the opening side of the concave portion for the longitudinal beam is the same as or more than the circumferential length on the flange side. Is also required to be formed large.
[0016]
At the same time, in order to avoid this, it is not preferable that the vertical beam protrudes inside each ring, because this restricts the effective inner diameter of the underground subsidence structure constructed by each ring. In the invention described in item 4, in the state in which the vertical beam is incorporated in the vertical beam housing space formed with the alignment of the concave portions for the vertical beam, the inner peripheral surface of the vertical beam is substantially the same as the inner peripheral surface of the reinforcing submerged body. It is a condition that they are set so as to form the same plane.
[0017]
According to a fifth aspect of the present invention, on the premise of the third or fourth aspect, the steel segment connects at least a pair of upper and lower main girders extending in the circumferential direction and both ends of the main girders. A pair of left and right joint plates, and a plurality of vertical ribs extending in the same direction as the joint plate and a skin plate functioning as an outer surface layer portion. And a pair of left and right side plates that connect both end portions of these main girders, and a plurality of vertical ribs extending in the same direction as the side plates.
[0018]
That is, since the vertical beam is accommodated so as to overlap with the vertical beam accommodating space formed with alignment of the concave portions for the vertical beam, in the invention according to claim 5, a skin plate is not provided at least for the vertical beam. Clarified what is not necessary.
[0019]
【The invention's effect】
According to the first and second aspects of the invention, since the reinforcing structure of the opening is constructed simply by incorporating the vertical beam into the vertical beam accommodating space formed by stacking the required number of press-fitting rings, This eliminates the need for the arrangement of rebars, the placement of concrete, and the accompanying curing period, and has the advantage of greatly contributing to the reduction of man-hours and the shortening of the work period.
[0020]
According to the third aspect of the present invention, each ring is formed by connecting a plurality of steel segments to each other. Therefore, the ring can be sequentially press-fitted into the ground while assembling the ring on the ground. As a result, the workability and ease of handling are further improved, and the vertical beams can be assembled into the vertical beam housing space from the inside of each ring, so that the workability is extremely good. Become.
[0021]
According to the invention described in claim 4, the inner circumferential surface of the longitudinal beam is set to be substantially flush with the inner circumferential surface of each ring in a state in which the longitudinal beam is incorporated in the longitudinal beam housing space. Thus, the effective inner diameter of the constructed underground structure is not limited by the arrangement of the vertical beams.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
1 and 2 are views showing a preferred embodiment of the invention, and show a schematic structure of an underground subsiding structure (hereinafter simply referred to as a substituting structure) 1 constructed by a steel segment press-fitting method.
[0023]
As shown in the figure, the substituting structure 1 includes short cylindrical press-fitting rings 2, 2,. By being fastened to each other, for example, it is configured as a cylindrical wall body whose depth is several times larger than the diameter. Each of the press-fitting rings 2, 2... Is divided into a plurality of steel segments having an arc shape in the circumferential direction, as will be described later, and the steel segments are fastened by using bolts and nuts in advance. It is assembled as the press-fit rings 2, 2.
[0024]
Then, after the construction of the subsidence structure 1, for example, a circular opening 4 is formed by cutting a part thereof so as to span a plurality of press-fitting rings 2, 2. In this embodiment, prior to forming the opening, the frame-shaped reinforcing structure (hatched lines in FIGS. 1 and 3 are surrounded by surrounding the portion to be the opening 4 from the top, bottom, left, and right). 5) are simultaneously formed in the construction stage of the substituting structure 1. In addition, the said opening part 4 is formed by fusing etc. from the inner side of the subsidence structure 1 after a construction.
[0025]
In the present embodiment, as the press-fit rings 2, 2..., In addition to the general plural rings 2A, 2A. 2B..., Lower opening side reinforcing ring 2C and opening upper side reinforcing ring 2D that are positioned on the lower side and upper side of the part where the opening 4 is formed, respectively, to reinforce them, and the lowermost blade edge The ring 2E is used in combination, and a pair of left and right vertical beams 6 that are incorporated later are used in such a manner as to straddle the opening lower reinforcing ring 2C from the opening lower reinforcing ring 2C. The opening lower reinforcing ring 2C, the opening upper reinforcing ring 2D, and the longitudinal beam 6 form the frame-shaped reinforcing structure 5 described above.
[0026]
As a construction procedure for constructing the subsidence structure 1, the lowermost blade edge ring 2E provided with the blade edge 7 is installed on the ground surface G of the construction site as shown in FIG. The side reinforcing ring 2C is stacked to form an intermediate assembly, and this intermediate assembly is press-fitted and submerged in the ground using a hydraulic press-fitting device (not shown). Then, after the press-fitting, the earth and sand inside the intermediate assembly is excavated using, for example, a bucket excavator.
[0027]
Subsequently, the one-stage or two-stage opening ring 2B is stacked on the intermediate assembly to increase the number of ring stages as the intermediate assembly. Drill the earth and sand inside the intermediate assembly. And the subsidence structure 1 as shown in FIG. 1 is constructed | assembled by repeating the stacking of such a one-step or several steps | paragraph of the press-fitting ring 2, press-fitting in the ground, and internal excavation one by one.
[0028]
Here, the general part rings 2A, 2A... Are joined to each other with bolts and nuts by butting arcuate steel segments 12, 12. When the general part rings 2A, 2A,... Are stacked, they are alternately arranged so that the phases of the butted portions of the steel segments 12, 12. And The individual steel segments 12, 12... Constituting the general part ring 2A are, in addition to a pair of upper and lower main girders 13, 13 and a pair of left and right joint plates 14, 14, as shown in FIG. The main plates 13 and 13 and the joint plate 14 are composed of a plurality of vertical ribs 15, 15... Having a substantially L-shaped cross section disposed in parallel with the joint plates 14 and 14 and a skin plate 16 constituting the outer surface. , 14 are formed with a plurality of bolt holes 17 for bolt connection with a steel segment as a counterpart.
[0029]
On the other hand, the lower opening reinforcing ring 2C, the opening ring 2B, and the upper opening reinforcing ring 2D have basically the same structure, and as shown in FIGS. In addition to the steel segments 12, 12..., A pair of adjustment segments 18, 18 that are tapered on one end and a pair of vertical beam installation segments 19, 19 that are also different on the left and right are brought into contact with each other. By fastening each other with a bolt and a nut, the left and right vertical beam recesses 20 are provided. When the opening lower reinforcement ring 2C, the opening rings 2B, 2B... And the opening upper reinforcement ring 2D are stacked, the vertical beam recesses 20, 20 are stacked so as to be aligned with each other. It is done. At the same time, the inner side surfaces 20a, 20a of the vertical beam recesses 20, 20,... Are set to be parallel to each other. In order to incorporate the vertical beam 6 from the inside into the vertical beam accommodating space 30 formed with a plurality of vertical beam recesses 20, 20, as will be described later, the opening side of the vertical beam recess 20 is as follows. This is because it is necessary to form the circumference of the same as or larger than the circumference on the back side.
[0030]
FIG. 7 shows details of the adjusting segment 18, and FIG. 8 shows details of the vertical beam installation segment 19, both of which are similar to the steel segment 12 shown in FIG. In addition to the main girders 21 and 21 and the pair of left and right joint plates 22 and 22, a plurality of vertical ribs 23 and 23 having a substantially L-shaped cross-section and parallel to the joint plates 22 and 22 and the outer surface are configured. A plurality of bolt holes 25, 25... Are formed in the main girders 21 and 21 and the joint plates 22 and 22.
[0031]
However, since the vertical beam installation segments 19 and 19 form the vertical beam recess 20, the width dimensions of the main girders 21 and 21 and the joint plates 22 and 22 (of FIG. 8A). The thickness dimension a) is set to about half of the other segments 12,18. Further, the steel segments 12, 12..., The adjustment segments 18, 18 and the vertical beam installation segments 19, 19 that constitute the opening lower reinforcing ring 2C and the opening upper reinforcing ring 2D are functions thereof. Accordingly, the plate thicknesses of the main girders 13 and 21 and the like are set to be particularly large compared to those on the side of the opening rings 2B, 2B.
[0032]
Therefore, by stacking the required number of opening rings 2B, 2B,... Together with the opening lower reinforcing ring 2C and the opening upper reinforcing ring 2D as described above, the vertical beam recesses 20, 20 of the rings 2C, 2D, 2B are stacked. A pair of left and right vertical beam accommodating spaces 30 having a length corresponding to the number of ring stages is formed with matching and matching.
[0033]
In this way, if the pair of left and right vertical beam receiving spaces 30 and 30 are formed together with the opening lower reinforcing ring 2C and the opening upper reinforcing ring 2D which are part of the reinforcing structure 5 in the construction process of the subsidence structure 1, In addition to FIGS. 1 to 3, as shown in FIG. 9, the vertical beams 6 are assembled and fixed to the vertical beam accommodating spaces 30, 30 from the inside.
[0034]
As shown in FIG. 10, the vertical beam 6 includes a plurality of main beams 31, 31... And a pair of left and right side plates 32 and 32 and vertical ribs 33 and 33. As shown in FIG. 11, as shown in FIG. 11, the entire circumference is welded and joined to the longitudinal beam housing space 30 from the inside. Thus, the reinforcing structure 5 is formed so as to surround the region to be the opening 4 with the opening lower reinforcing ring 2B, the opening upper reinforcing ring 2D, and the longitudinal beam 6.
[0035]
Thereafter, at the stage where the subsidence structure 1 is subsidized to a predetermined depth, the opening 4 is formed from the inside of the subsidence structure 1 by means such as fusing so as to straddle the plurality of opening rings 2B, 2B. At this time, as a part of the main girders of the opening rings 2B, 2B... Are cut and removed, the load bearing capacity at the opening rings 2B, 2B. The strength reduction can be compensated by dispersing the load that should be originally borne by the opening rings 2B, 2B...
[0036]
As described above, according to the present embodiment, since the reinforcing structure 5 is built around the opening 4 at the same time as the construction of the subsidence structure 1, the number of man-hours and the construction period are shortened compared with the conventional method. Can be planned.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating a preferred embodiment of the present invention, and is a front explanatory view of an underground subsidence structure.
2 is a cross-sectional view taken along line AA in FIG.
FIG. 3 is an enlarged explanatory view of the main part of FIG.
4 is an enlarged sectional view taken along line BB in FIG. 3;
5A is an enlarged cross-sectional view of a steel segment that constitutes the general ring of FIG. 4, and FIG. 5B is a front explanatory view thereof.
6 is an enlarged cross-sectional view taken along the line CC of FIG.
7A is an enlarged sectional view of an adjustment segment that constitutes the opening ring of FIG. 6, and FIG. 7B is an explanatory front view thereof.
8A is an enlarged cross-sectional view of a vertical beam installation segment that constitutes the opening ring of FIG. 6, FIG. 8B is a front view thereof, and FIG. 8C is a left side view thereof.
9 is a cross-sectional explanatory diagram when a vertical beam is assembled from the state of FIG. 6;
10A is an enlarged cross-sectional explanatory view of the vertical beam shown in FIG. 9, and FIG. 10B is a front explanatory view thereof.
11 is an explanatory cross-sectional view showing a state in which the vertical beam has been assembled from the state shown in FIG. 9;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Underground structure 2 ... Press-fit ring 2A ... General part ring 2B ... Opening part ring 2C ... Opening part lower side reinforcement ring 2D ... Opening part upper side reinforcement ring 4 ... Opening part 5 ... Reinforcement structure part 6 ... Vertical beam 12 ... Steel Segment 13 ... Main girder 14 ... Joint plate 15 ... Vertical rib 16 ... Skin plate 18 ... Adjustment segment 19 ... Vertical beam installation segment 20 ... Vertical beam recess 21 ... Main girder 22 ... Joint plate 23 ... Vertical rib 24 ... Skin plate 30 ... Vertical beam housing space 31 ... Main girder 32 ... Side plate 33 ... Vertical rib

Claims

It is constructed as a cylindrical wall body by stacking the press-fitting rings into the ground sequentially while stacking the press-fitting rings in multiple stages, and after the construction, an opening is formed so as to span a plurality of press-fitting rings on a part of the side wall. A method of constructing an underground subsidence structure that is formed,
A step of press-fitting and sinking an opening lower reinforcement ring in which a longitudinal beam concave portion is formed in advance at portions that will be located on both sides of the opening equivalent position and the lower side of the opening equivalent position is reinforced. When,
With respect to the opening ring in which the longitudinal beam recesses are formed in advance on the both sides of the position corresponding to the opening, the position of the longitudinal beam recess is aligned with that on the lower reinforcing ring side of the opening. A step of stacking while pressing and sinking sequentially on the lower reinforcing ring of the opening by the number of steps involved in forming the opening; and
A vertical beam recess is formed in advance on the both sides of the position corresponding to the opening, and the opening upper reinforcing ring that reinforces the upper side of the position corresponding to the opening is used for the vertical beam. A step of press-fitting and sinking on the opening ring while aligning the position of the recess with the opening ring side;
The longitudinal beam containing space formed with the alignment of the concave portions for the vertical beam has a length extending over the opening lower reinforcing ring, the multi-stage opening ring and the opening upper reinforcing ring so as to be aligned with the space. Incorporating and reinforcing vertical beams from the inside of each ring;
A method of constructing an underground subsidence structure characterized by comprising:

It is constructed as a cylindrical wall body by stacking the press-fitting rings into the ground sequentially while stacking the press-fitting rings in multiple stages, and after the construction, an opening is formed so as to span a plurality of press-fitting rings on a part of the side wall. It is a reinforcing structure for the underground subsidence structure that is formed,
A vertical beam concave portion is formed in advance at sites that will be located on both sides of the opening equivalent position, and the opening lower reinforcement ring that reinforces the lower side of the opening equivalent position;
Longitudinal beam recesses are formed in advance on the portions that will be located on both sides of the position corresponding to the opening, and the position of the vertical beam recess is aligned with that on the lower reinforcing ring side of the opening. A plurality of stage opening rings sequentially stacked on the side reinforcing ring by the number of stages involved in the formation of the opening,
Longitudinal beam recesses are formed in advance on the portions to be located on both sides of the position corresponding to the opening, and the position of the recesses for the vertical beam is aligned with that on the opening ring side. An opening upper reinforcing ring that reinforces the upper side of the opening equivalent position by being disposed on the upper side;
With
The longitudinal beam containing space formed with the alignment of the concave portions for the vertical beam has a length extending over the opening lower reinforcing ring, the multi-stage opening ring and the opening upper reinforcing ring so as to be aligned with the space. Reinforcement structure for underground subsidence structures, which are reinforced by incorporating vertical beams from the inside of each ring.

The opening lower reinforcement ring, the opening ring and the opening upper reinforcement ring are all formed as a ring by connecting a plurality of steel segments to each other,
Above the longitudinal beams recess, between the steel segments of the adjacent general section, and generally part steel segments adjacent thereto a thin steel segment thick having an inner peripheral length of the equivalent longitudinal beams circumferential length Is formed in a concave shape by sandwiching and connecting together with steel segments with different shapes at one end, and in order to allow the vertical beam to be incorporated from the inside of each ring, the opening side of the vertical beam recess The reinforcement structure for an underground subsidence structure according to claim 2, wherein the circumference is formed to be equal to or greater than the circumference on the buttock side.

In the state where the vertical beam is incorporated in the vertical beam receiving space formed by aligning the concave portions for the vertical beam, the inner peripheral surface of the vertical beam is set to be substantially flush with the inner peripheral surface of each ring. The reinforcing structure for an underground subsidence structure according to claim 3.

The steel segment includes at least a pair of upper and lower main girders extending in the circumferential direction, a pair of left and right joint plates that connect both ends of the main girders, and a plurality of joint plates that extend in the same direction as the joint plates. While being formed from vertical ribs and skin plates that function as outer surface layers,
The vertical beam is formed of at least a pair of upper and lower main girders, a pair of left and right side plates connecting both ends of the main girders, and a plurality of vertical ribs extending in the same direction as the side plates. The reinforcing structure for an underground subsidence structure according to claim 3 or 4.