JP3647798B2

JP3647798B2 - Construction method of mountain retaining work and bag body therefor

Info

Publication number: JP3647798B2
Application number: JP2001365475A
Authority: JP
Inventors: 利行村本; 英孝田中; 義則小黒; 太司清水
Original assignee: Ashimori Industry Co Ltd; Sato Kogyo Co Ltd
Current assignee: Ashimori Industry Co Ltd; Sato Kogyo Co Ltd
Priority date: 2001-11-30
Filing date: 2001-11-30
Publication date: 2005-05-18
Anticipated expiration: 2021-11-30
Also published as: JP2003166242A

Description

【０００１】
【発明の属する技術分野】
本発明は、前記山留め支保工の腹起しと山留め壁との間の間詰め工程及び山留め壁の加圧工程の作業を簡略化でき、かつこれら２工程の作業を効率的に行えるようにした山留め支保工の施工方法およびそのための袋体に関する。
【０００２】
【従来の技術】
従来より、カルバートボックス、地下タンク、地下鉄トンネルの駅部、大型基礎構造物などの地下構造物または地下部分を含む構造物を建設するに当たっては、山留め壁および山留め支保工によって周辺地盤の崩壊および変位を防止しながら地盤の掘削が行われている。図８はその一例として、シートパイル（鋼矢板）５０によって周囲との締め切りを行い、地盤の掘削に伴って順次、腹起し５１および切梁５２等の山留め支保工を設置しながら掘削を進める場合の土留め架設構造物例を示したものである。掘削手順に従いながら概説すると、先ず掘削に先立ってバイブロハンマーなどの杭打ち機を使用して前記シートパイル５０の建込みを行う。前記シートパイル５０は、両端部に部材長手方向に沿って継手を備え、隣接するシートパイル５０、５０同士を相互に連結しながら平面視で地下構造物の形状に合わせ、方形状または円形状に建込みが行われる。前記シートパイル５０の建込みが完了したならば、シートパイル５０によって囲まれた内部を掘削機により掘削を開始する。その後、所定の深さ間隔毎に腹起し５１および切梁５２等からなる山留め支保工を設置し、シートパイル５０に変位が生じないようにしながら掘削を継続する。
【０００３】
前記腹起し５１および切梁５２等の設置に当たっては、図９に示されるように、山留め支保工設置レベルよりも０．７〜１．５ｍ程度だけ深く根切り（掘削）した後、山留め壁（シートパイル）５０にブラケット５３等を溶接等によって固定し、このブラケット５３，５３…上に腹起し５１を載置したならば、腹起し５１の背面に底型枠を設置して裏込コンクリート５４を打設し、その後、切梁５２を腹起し５１、５１間に横架しコンクリート等の硬化を待って、切梁５２の中間に介在させたジャッキ５５によりプレロード（壁面加圧）を与え山留め壁５０を加圧するようにしている。なお、前記裏込コンクリートに代えて、木製キャンバー、鋼製キャンバー等のクサビ部材や土嚢袋、アルミ製裏込部材を使用することもある。
【０００４】
【発明が解決しようとする課題】
しかしながら、従来の山留め支保工において、腹起しの背面側に裏込コンクリート５４を打設する場合には、底型枠及び側型枠を必要とし、その設置に多くの手間と時間を要していた。すなわち、シートパイル５０はもちろんの事、特に鋼管矢板等の場合には土留め壁面形状が複雑で、その壁面形状に合わせて型枠用合板を裁断し設置する作業に多くの時間と労力を必要としていた。また、裏込コンクリートによる間詰めの場合、プレロードを与えるのに強度発現を待つ必要があるなどの問題があった。
【０００５】
さらに、前述の腹起しおよび切梁等とからなる山留め支保工の場合、設計思想は土留め壁と腹起しとが裏込コンクリートやクサビ部材等を介して密着することを前提としており、土留め壁と腹起しとの隙間を前述のように、裏込コンクリートの場合はまだしも、クサビ部材や土嚢袋等によって封鎖する場合には設計思想に合致するように、各腹起しに均等な荷重分布を発生させることは困難である等の問題があった。
【０００６】
他方、プレロードの導入に際しては、ある程度の長い区間を同時に加圧することが望ましいが、切梁本数だけの油圧ジャッキが必要となるため、載荷装置および油圧ジャッキの損料的負担が大きくなるなどの問題が発生する。そのため、現場では１本〜複数本の切梁を対象としてジャッキによりプレロードを掛け、コマ用鋼材を挿入してジャッキを撤去するようにすることが行われている。しかし、この場合にはプレロードを保持したままコマ鋼材を挿入するのに多大な手間が掛かるとともに、ジャッキによってプレロードを掛けた際、隣接する切梁のプレロードを緩めてしまうため、再度ジャッキを挿入して再加圧、再々加圧が必要となることがあり、プレロード管理がかなり煩雑な作業となり、余計に手間と時間が掛かっていた。
【０００７】
そこで本発明は前述した問題点に鑑み成されたもので、その主たる課題は型枠等の設置作業を無くし作業の省力化を図ること、およびジャッキ等のプレロード導入手段を省略することが可能で、しかも山留め壁と腹起しとの間詰めからプレロード導入までの工程を効率的に行うことができ、かつ設計思想に合致したプレロードの載荷を行い、また軸力低下に伴う再加圧も簡単に行うことができる等、各種の利点を有する山留め支保工の施工方法およびそのための袋体を提供することにある。
【０００８】
【課題を解決するための手段】
前記課題を解決するために請求項１に係る本発明として、地盤掘削に伴って山留め壁に山留め支保工を設置するための施工方法であって、
山留め支保工の腹起しと山留め壁との間に、弾性伸びが小さくかつ所定の引張強度を有する織物からなるとともに、遮水性を有する袋体を設置し、前記袋体内部に流動性材料を加圧注入することにより、前記山留め支保工の腹起しと山留め壁との間の間詰めと、山留め壁の加圧とを行うことを特徴とする山留め支保工の施工方法が提供される。
【０００９】
上記請求項１記載の発明においては、袋体として、弾性伸びが小さくかつ所定の引張強度を有する織物からなるとともに、遮水性を有する袋体を用いるようにしている。ゴムのように高い弾性伸びを示す場合には、内部に流動性材料を注入しても非拘束側、この場合は上下面側を膨らましながら圧力が逃げてしまい加圧効率が悪いが、弾性伸びが小さくかつ高強度の素材からなる袋体を用いることにより、膨出圧によって確実に山留め支保工の腹起しと山留め壁との間の間詰めと、山留め壁の加圧とを行い得るようになる。具体的に前記袋体として、合成繊維織物またはガラス繊維織物に遮水性機能を持たせるためのコーティングを施したものが好適に用いられる。
また、本発明では、腹起しの背面側に配置された袋体の内部に流動性材料を単に充填若しくは注入するのではなく、山留め壁に所定の圧力を与え得る状態にまで積極的に加圧注入を行うようにしている。したがって、前記袋体が確実に腹起しと山留め壁とに密着し山留め壁にプレロードを導入できるようになる。また、従来の裏込コンクリートのように強度発現まで待つ必要が無く、かつ間詰め工程および加圧工程を実質的に一工程で連続的に行うことが可能となる。さらに、型枠設置工が不要となるとともに、加圧用ジャッキなども不要にできるため、大幅に作業が省力化されるとともに、長い区間を一度に施工できるため、極めて効率的に山留め支保工の設置作業が可能となる。加えて、山留め加圧後における再加圧に際しても、加圧注入を繰り返すだけで簡単に行うことができるなどの種々の利点をもたらすものとなる。
【００１０】
請求項２に係る本発明として、地盤掘削に伴って山留め壁に山留め支保工を設置するための施工方法であって、
山留め支保工の腹起しと山留め壁との間に、袋体と、この袋体内部に内設されるとともに、所定長さを有し他方端開口を袋体内部に臨ませた山留め壁加圧用チューブとからなる袋体を設置し、前記袋体内部に相対的に流動性の低い一次注入材を充填し前記山留め支保工の腹起しと山留め壁との間の間詰めを行った後、前記山留め壁加圧用チューブを通して相対的に流動性の高い二次注入材を加圧注入し、径が拡大するように前記山留め壁加圧用チューブを膨出させることにより山留め壁の加圧を行うことを特徴とする山留め支保工の施工方法が提供される。
【００１１】
請求項３に係る本発明として、地盤掘削に伴って山留め壁に山留め支保工を設置するための施工方法であって、
山留め支保工の腹起しと山留め壁との間に、袋体と、この袋体内部に端部間に亘って内設され開放部を有しない山留め壁加圧用チューブとからなる袋体を設置し、前記袋体と山留め壁加圧用チューブとの空間部分に相対的に流動性の低い一次注入材を充填し前記山留め支保工の腹起しと山留め壁との間の間詰めを行った後、前記山留め壁加圧用チューブ内に相対的に流動性の高い二次注入材を加圧注入し、径が拡大するように前記山留め壁加圧用チューブを膨出させることにより山留め壁の加圧を行うことを特徴とする山留め支保工の施工方法が提供される。
【００１２】
請求項４に係る本発明として、前記一次注入材は硬化性材料であり、前記二次注入材は流動性材料である請求項２，３いずれかに記載の山留め支保工の施工方法が提供される。
【００１３】
上記請求項２〜４記載の本発明では、袋体内部に山留め壁加圧用チューブを設け、山留め支保工の腹起しと山留め壁との間の間詰め用に相対的に流動性の低い一次注入材を注入した後、前記山留め壁加圧用チューブを通して山留め壁加圧用相対的に流動性の高い二次注入材を加圧注入するようにした。したがって、山留め壁の加圧を均等に行い得るようになる。
【００１４】
請求項５に係る本発明として、前記山留め壁の加圧は、０．４MPa以上の圧力を与えるようにする請求項１〜４いずれかに記載の山留め支保工の施工方法が提供される。袋体内への流動性材料の単なる充填または注入では、0.05〜0.1MPa程度の圧力状態しか見込めないが、袋体をジャッキの代用とするために、山留め壁の加圧力が０．４MPa以上の圧力となるように流動性材料の加圧注入を行うことで、本発明の目的を達するプレロードとして十分なものとなる。
【００１５】
請求項６に係る本発明として、弾性伸びが小さくかつ所定の引張強度を有する織物からなるとともに、遮水性を有する袋体の少なくとも一方側端部にバルブを備えたことを特徴とする請求項１記載の山留め支保工の施工方法のための袋体が提供される。
【００１６】
請求項７に係る本発明として、袋体と、この袋体内部に内設されるとともに、前記袋体の一方端から所定長さを有し他方端開口を袋体内部に臨ませ、径が拡大するように膨出することにより山留め壁の加圧を行う山留め壁加圧用チューブとからなることを特徴とする請求項２〜５いずれかに記載の山留め支保工の施工方法のための袋体が提供される。
【００１７】
請求項８に係る本発明として、袋体と、この袋体内部に内設されるとともに、前記袋体の一方端から所定長さを有し他方端開口を袋体内部に臨ませ、径が拡大するように膨出することにより山留め壁の加圧を行う山留め壁加圧用チューブとからなり、少なくとも一方端側に前記山留め壁加圧用チューブ内への連通路を開閉するバルブを備えたことを特徴とする請求項２、４、５いずれかに記載の山留め支保工の施工方法のための袋体が提供される。
【００１８】
請求項９に係る本発明として、袋体と、この袋体内部に内設されるとともに、前記袋体の一方端から所定長さを有し他方端開口を袋体内部に臨ませ、径が拡大するように膨出することにより山留め壁の加圧を行う山留め壁加圧用チューブとからなり、一方端側に前記袋体と山留め壁加圧用チューブとの間の空間への連通路を開閉するとともに、前記山留め壁加圧用チューブ内への連通路を開閉する二重構造バルブを備えたことを特徴とする請求項２、４，５いずれかに記載の山留め支保工の施工方法のための袋体が提供される。
【００１９】
請求項１０に係る本発明として、袋体と、この袋体内部に端部間に亘って内設され開放部を有せず、径が拡大するように膨出することにより山留め壁の加圧を行う山留め壁加圧用チューブとからなり、一方端側に前記袋体と山留め壁加圧用チューブとの間の空間への連通路を開閉するとともに、前記山留め壁加圧用チューブ内への連通路を開閉する二重構造バルブを備えたことを特徴とする請求項３、４，５いずれかに記載の山留め支保工の施工方法のための袋体が提供される。
【００２０】
請求項１１に係る本発明として、前記袋体は弾性伸びが小さくかつ所定の引張強度を有する織物からなるとともに、遮水性を有する請求項７〜１０いずれかに記載の袋体が提供される。
【００２１】
【発明の実施の形態】
以下、本発明の実施の形態について図面を参照しながら詳述する。
【００２２】
本山留め支保工が対象とする山留め壁としては、シートパイル（鋼矢板）、鋼管矢板などの鋼製矢板の他、ソイルセメント柱列壁、ＲＣ柱列壁、鋼管柱列壁などの柱列式山留め壁、場所打ちＲＣ地中壁、ＰＣ板地中壁などの連続地中壁および親杭横矢板などの各種山留め壁を対象とすることができ、山留め支保工としては、大別すると、腹起し・切梁式山留め支保工と、アンカー式山留め支保工とが存在するが、前者の腹起し・切梁式山留め支保工（腹起しのみの場合を含む。）または両者を併用した山留め支保工を対象とすることができる。
【００２３】
前記腹起し・切梁式山留め支保工は、図１に示されるように、山留め壁１にブラケット２等を溶接等によって固定し、このブラケット２，２…上に袋受け板を横架するとともに、腹起し３を横架したならば、腹起し３と山留め壁１との間に土留め壁の線形や不陸吸収のために空けた隙間部分に、内部エアを抜いて萎んだ状態の間詰め・加圧用袋体５（以下、単に袋体という。）を挿入し、かつ腹起し３，３間に切梁４を横架し支保工を組み立てる。なお、前記袋体５については腹起し３の背面側に位置していればよく、予め腹起し３に取り付けておいてもよい。
【００２４】
ここまでの作業が完了したならば、前記袋体５内部に流動性材料を加圧注入することにより、前記山留め支保工の腹起し３と山留め壁１との間の間詰めと、山留め壁１の加圧とを連続的に行うようにする。ここで、「連続的」とは間詰めと加圧との間に時間を置かずに両工程をほぼ同時的に行う場合と、ある程度の時間を置いた後、加圧を行う場合の両者を意味する。すなわち、間詰め工程後に加圧のための準備作業を特段に要さず加圧工程を連続して行えることを意味する。前記流動性材料としては、たとえば水、泥水等の液体や、モルタル、コンクリート等の硬化性材料等、非圧縮性を有する少なくとも注入時に流動性を示す材料であればどのようなものでも使用することができる。
【００２５】
前記袋体５は、可撓性（易変形性）を有し、内部への流動性材料の注入に伴って膨出する袋体が使用されるが、素材としては、ゴムのように高い弾性伸びを示す場合には、内部に流動性材料を注入しても非拘束側、この場合は上下面側を膨らましながら圧力が逃げてしまい加圧効率が悪いため、例えば合成繊維織物またはガラス繊維織物などの弾性伸びの小さくかつ所定の引張強度を有する素材に遮水機能を持たせるためのコーティングを施したものが好適に使用される。また断面形状は、図２に示されるような円断面の他、縦長の方形断面等、膨出状態で山留め壁面側を効率よく加圧できれば任意の断面形状とすることができる。
【００２６】
袋体５の構造は、図２及び図３に示されるように、両端部にそれぞれ開閉バルブ６，７を備えるようにし、これら開閉バルブ６，７の一方側を流動性材料の注入口として使用し、他方側をエア抜き孔として使用するようにする。具体的には、開閉バルブ６の側に流動性材料の供給ホースを接続し、他方の開閉バルブ７は空気排出路とするためコック７ａを開としておき、前記流動性材料注入側開閉バルブ６のコック６ａを開いて圧送ポンプによって送られた流動性材料を袋体５内に注入し、その後開閉バルブ７側から流動性材料が吐出したことを確認したならばコック７ａを閉じるようにする。続けて、山留め壁１の加圧を行う場合には、所定の加圧力になるまで流動性材料の注入を継続して行った後、コック６ａを閉じる。所定の加圧力になったかどうかは、例えば切梁４の中間に軸力計を挿入しこれを計測することにより確認することができる。この場合、前記山留め壁１の加圧は、０．４MPa以上の圧力を与えるようにするのが望ましい。
【００２７】
ところで、前記流動性材料として比較的粘性のあるモルタルやコンクリート等を使用した場合、発明者等による実験等によれば、条件によっては相対的に注入側の加圧力が高く、距離が離れるに従って徐々に加圧力が減少していることが知見された。その結果、遠方側で所定の加圧力を確保するためには、注入側近傍の圧力が高くなり過ぎ無駄があることが判明した。そこで本発明では、このような加圧力の偏りを無くすためには、図４に示されるように、内部に山留め壁加圧用チューブ９を備えた二重袋体８が提案される。
【００２８】
図４に示される二重袋体８の第１例は、可撓性を有する袋体５と、この袋体５内部に内設されるとともに、一方端から所定長さを有し他方端開口９ａを袋体５内部に臨ませた山留め壁加圧用チューブ９とからなり、一方端側に前記山留め壁加圧用チューブ９内への連通路を開閉するバルブ１０を備え、かつ他方端側に前記袋体５内への連通路を開閉するバルブ１１を備えた構造となっている。
【００２９】
先ず、他方側開閉バルブ１１を開としてエア抜き孔とした状態で、山留め壁加圧用チューブ９を通して袋体５と山留め壁加圧用チューブ９との空間部分に相対的に高い粘性を有する、例えばモルタルまたはコンクリート等の硬化性材料を充填（一次注入）し、前記山留め支保工の腹起し３と山留め壁１との間の間詰めを行う。開閉バルブ１１側から前記硬化性材料が吐出したことを確認したならばコック１１ａを閉じるようにする。次いで前記間詰め工程に連続して、前記山留め壁加圧用チューブ９を通して相対的に粘性の低い流動性材料、例えば水、水セメント比の大きいモルタル、セメントミルク等を加圧注入（二次注入）し、加圧力の均等化を図りながら山留め壁への加圧を行うようにする。前記二次注入によって山留め壁加圧用チューブ９が径を拡大するように膨出することで袋体５が膨出し長手方向に均等に加圧力を発生させるようになる。なお、前記硬化性材料の一次注入は反対側の開閉バルブ１１側から行うようにしてもよい。また、前記山留め壁加圧用チューブ９は、ある程度以上の圧力になると、チューブ壁面から二次注入材が滲出するようにし全体を均一に加圧することもできる。
【００３０】
次いで、第２の態様としては、図５に示される二重袋体８’は、袋体構造を同一として、一方端側に前記袋体５と山留め壁加圧用チューブ９との空間への連通路を開閉するとともに、前記チューブ９内への連通路を開閉する二重構造バルブ１２を備え、他方端側に前記袋体５と山留め壁加圧用チューブ９との間の空間への連通路を開閉するバルブ１１を備えた構造となっている。
【００３１】
先ず、他方側開閉バルブ１１を開としてエア抜き孔とした状態で、袋体５と山留め壁加圧用チューブ９との間の空間部分に例えばモルタルまたはコンクリート等の硬化性材料を充填（一次注入）し、前記山留め支保工の腹起し３と山留め壁１との間の間詰めを行った後、次いで前記間詰め工程に連続して、前記山留め壁加圧用チューブ９を通して例えば水、水セメント比の大きいモルタル等を加圧注入（二次注入）し加圧力の均等化を図りながら山留め壁への加圧を行うようにする。前記二次注入によって山留め壁加圧用チューブ９が径を拡大するように膨出することで袋体５が膨出し長手方向に均等に加圧力を発生させるようになるとともに、粘性の低い二次注入材料が山留め壁加圧用チューブ９の他方端開口９ａを中心として注入され、山留め壁加圧用チューブ９の他方端９ａ側の加圧力が増大されることにより、加圧力の偏りが補正され、より一層加圧力の均等化が図れるようになる。
【００３２】
更に、第３の態様に係る二重袋体１３は、図６に示されるように、可撓性を有する袋体５と、この袋体５内部に端部間に亘って内設され開放部を有しない山留め壁加圧用チューブ１４とからなり、一方端側に前記袋体５と山留め壁加圧用チューブ１４との空間への連通路を開閉するとともに、前記山留め壁加圧用チューブ１４内への連通路を開閉する二重構造バルブ１２を備え、他方端側に前記袋体５と山留め壁加圧用チューブ１４との間の空間への連通路を開閉するバルブ１５を備えた構造となっている。なお、前記他方端側の開閉バルブも二重構造バルブ１２としてもよい。
【００３３】
かかる二重袋体１３の場合は、他方側開閉バルブ１５を開としてエア抜き孔とした状態で、先ず前記二重構造バルブ１２のコック１２ａを開操作し、前記袋体５と山留め壁加圧用チューブ１４との空間への連通路を開けるとともに、袋体５と山留め壁加圧用チューブ１４との間の空間部分に例えばモルタルまたはコンクリート等の硬化性材料を充填（一次注入）する。その後、開閉バルブ１５から一次注入材が吐出したことを確認したならば開閉バルブ１５を締め、袋体５内に一次注入材が充満したならば二重構造バルブ１２のコック１２ａを閉め、山留め支保工の腹起し３と山留め壁１との間の間詰めを完了する。次いで前記二重構造バルブ１２のコック１２ｂを開操作し、山留め壁加圧用チューブ１４への連通路を開け、前記山留め壁加圧用チューブ１４内に例えば水、水セメント比の大きいモルタル等を加圧注入（二次注入）し加圧力の均等化を図りながら山留め壁への加圧を行うようにする。
【００３４】
以上の要領により、腹起しと山留め壁との間の間詰めと、山留め壁の加圧とを完了したならば、数分間そのまま放置し加圧力が低下していないかを確認し、必要に応じて再注入を行う。この再注入はその後においても、山留め壁の加圧力が低下した任意の時に行うことができる。なお、前記袋体５，８…への流動性材料の加圧注入は切梁を跨いで対向する腹起しの片側のみで行うようにしても良いし、対向する腹起しの両側で同時に行うようにしてもよい。さらに、例えば掘削に伴って最下段に支保工を設置した際、山留め壁１の僅かの変位によって相対的に上段側の支保工において緩み（加圧力の低下）が発生することがある。このような加圧力の低下を防止するため、上段側の１または複数段において、新たに設置した支保工の加圧注入と同時に再加圧注入を行うようにしてもよい。
【００３５】
ところで、上記例では袋体５、二重袋体８，１３によって腹起しと山留め壁との間の間詰めと共に、山留め壁の加圧を行うようにしたが、切梁に補助的に加圧用ジャッキを介在させ、この加圧用ジャッキを併用しながら山留め壁１の加圧を行うようにしてもよい。また、前記袋体については山留め壁面形状に合わせた外形状とすることもできる。たとえば、図７に示されるように、断面コ字状のシートパイル２０，２０…を使用した場合などは山留め壁面が凹凸面となるが、この凹凸面に合わせるように、小断面部２１ａと大断面部２１ｂとを交互に配列した異形数珠状の袋体２１とすることもできる。
【００３６】
【発明の効果】
以上詳説のとおり本発明によれば、型枠等の設置作業を無くし作業の省力化を図り得るようになるとともに、ジャッキ等のプレロード導入手段を省略することが可能となる。また、山留め壁と腹起しとの間詰めからプレロード導入までの工程を効率的に行うことができるようになるとともに、軸力低下に伴う再加圧も簡単に行うことができる等、種々の利点を有するものとなる。
【図面の簡単な説明】
【図１】本発明に係る山留め支保工の要部断面図である。
【図２】袋体５の斜視図である。
【図３】その縦断面図である。
【図４】第１態様に係る二重袋体８の縦断面図である。
【図５】第２態様に係る二重袋体８’の縦断面図である。
【図６】第３態様に係る二重袋体１３の縦断面図である。
【図７】袋体外形状の変形例図である。
【図８】従来の切梁・腹起し式山留め支保工の要部斜視図である。
【図９】腹起し及び切梁の設置要領図である。
【符号の説明】
１…山留め壁、２…ブラケット、３…腹起し、４…切梁、５…袋体、８・８’・１３…二重袋体、６・７・１１・１５…開閉バルブ、１２…二重構造バルブ、９・１４…山留め壁加圧用チューブ[0001]
BACKGROUND OF THE INVENTION
According to the present invention, the work of the filling process between the uplift and the retaining wall of the retaining support and the retaining wall pressurizing process can be simplified, and these two processes can be performed efficiently. The present invention relates to a construction method of a mountain retaining work and a bag body therefor.
[0002]
[Prior art]
Conventionally, when constructing underground structures such as culvert boxes, underground tanks, subway tunnel stations, large foundation structures, or structures including underground parts, the surrounding ground collapses and displaces due to retaining walls and retaining structures. Excavation of the ground is being carried out while preventing this. FIG. 8 shows an example in which a sheet pile (steel sheet pile) 50 is closed with the surroundings, and excavation is proceeded while installing upright support 51 such as an upset 51 and a cut beam 52 as the ground is excavated. The earth retaining structure example in the case is shown. Outlined in accordance with the excavation procedure, the sheet pile 50 is first installed using a pile driving machine such as a vibro hammer prior to excavation. The sheet pile 50 is provided with joints at both ends along the longitudinal direction of the member, and the adjacent sheet piles 50 and 50 are connected to each other to match the shape of the underground structure in a plan view, thereby forming a square shape or a circular shape. Construction is carried out. When the installation of the sheet pile 50 is completed, the excavator starts excavating the interior surrounded by the sheet pile 50. Thereafter, a pile support 51 consisting of a bulge 51 and a cut beam 52 is installed at every predetermined depth interval, and excavation is continued while the seat pile 50 is not displaced.
[0003]
As shown in FIG. 9, when installing the erection 51 and the cutting beam 52, after deepening (excavating) about 0.7 to 1.5 m deeper than the installation level of the mountain support, the mountain retaining wall (Sheet Pile) When a bracket 53 or the like is fixed to the (sheet pile) 50 by welding or the like, and an uprising 51 is placed on the brackets 53, 53... Inserted concrete 54 is placed, and then the cut beam 52 is erected upright, 51b is placed between 51 and 51, and the concrete or the like is hardened. ) To pressurize the retaining wall 50. In addition, it replaces with the said back concrete, and wedge members, such as a wooden camber and steel camber, a sandbag, and an aluminum back member may be used.
[0004]
[Problems to be solved by the invention]
However, in the case of placing the backing concrete 54 on the back side of the erection in the conventional support structure, the bottom formwork and the side formwork are required, and the installation requires a lot of labor and time. It was. That is, not only the sheet pile 50, but particularly steel pipe sheet piles, the earth retaining wall surface shape is complicated, and it takes a lot of time and labor to cut and install the formwork plywood according to the wall surface shape. I was trying. In addition, in the case of interlining with back-filled concrete, there is a problem that it is necessary to wait for strength development to give a preload.
[0005]
Furthermore, in the case of the mountain retaining support composed of the above-mentioned erection and cutting beam, the design philosophy is based on the premise that the earth retaining wall and the erection are in close contact with each other through the back concrete, wedge member, etc. As described above, the gap between the retaining wall and the erection is equal for each erection so that it conforms to the design philosophy if it is sealed with a wedge member or sandbag, etc. There is a problem that it is difficult to generate the distribution.
[0006]
On the other hand, when introducing a preload, it is desirable to pressurize a certain length of sections at the same time, but since there is a need for hydraulic jacks corresponding to the number of cut beams, there is a problem such as increasing the damaging burden on the loading device and the hydraulic jack. Occur. For this reason, on the site, one to a plurality of cut beams are preloaded with a jack, and the jack is removed by inserting a steel material for the top. However, in this case, it takes a lot of time to insert the top steel material while holding the preload, and when the preload is applied by the jack, the preload of the adjacent beam will be loosened. In some cases, re-pressurization and re-pressurization may be necessary, and preload management is a complicated task, which takes extra time and effort.
[0007]
Therefore, the present invention has been made in view of the above-mentioned problems, and the main problems are that it is possible to eliminate the installation work of the formwork and the like to save labor, and to omit the preload introduction means such as the jack. In addition, the process from filling up the retaining wall and the erection to the preload introduction can be performed efficiently, and the preload can be loaded according to the design philosophy. An object of the present invention is to provide a construction method of a mountain retaining support having various advantages such as being able to be performed and a bag body therefor.
[0008]
[Means for Solving the Problems]
As the present invention according to claim 1 for solving the above-mentioned problem, it is a construction method for installing a mountain retaining work on a mountain retaining wall in conjunction with ground excavation,
A bag body having a small elastic elongation and having a predetermined tensile strength and having a water-impervious property is installed between the erection of the mountain retaining support and the mountain retaining wall, and a fluid material is placed inside the bag body. By pressurizing and injecting, there is provided a construction method for a mountain retaining structure, characterized in that the space between the erection of the mountain retaining structure and the retaining wall is compressed and the retaining wall is pressurized.
[0009]
In the first aspect of the present invention, the bag body is made of a woven fabric having a small elastic elongation and a predetermined tensile strength, and has a water shielding property . In the case of high elastic elongation such as rubber, even if fluid material is injected inside, the pressure escapes while inflating the non-restraining side, in this case the upper and lower surfaces, and the pressure efficiency is poor. By using a bag made of a material having a small size and high strength, it is possible to reliably perform filling between the erection of the mountain retaining support and the mountain retaining wall and pressurization of the mountain retaining wall by the bulging pressure. become. Specifically, as the bag body, a synthetic fiber woven fabric or a glass fiber woven fabric that has been provided with a coating for imparting a water shielding function is preferably used.
Further, according to the present invention, rather than simply filling or injecting a fluid material into the inside of the bag disposed on the back side of the abdomen, it is actively applied to a state where a predetermined pressure can be applied to the retaining wall. Pressure injection is performed. Therefore, the bag body can surely rise up and be in close contact with the retaining wall, and a preload can be introduced into the retaining wall. Moreover, it is not necessary to wait for strength development like the conventional lining concrete, and it becomes possible to perform a stuffing process and a pressurization process continuously in one process substantially. In addition, since the installation work for the formwork is not required and the jack for pressurization can be made unnecessary, the work is greatly saved, and the long section can be constructed at one time. Work becomes possible. In addition, various advantages such as being able to be performed simply by repeating the pressurization when re-pressurizing after press-clamping are provided.
[0010]
As the present invention according to claim 2, a construction method for installing a mountain retaining support on a mountain retaining wall with ground excavation,
A bag body and a mountain retaining wall provided inside the bag body and having a predetermined length with the other end opening facing the inside of the bag body between the upright of the mountain retaining support and the mountain retaining wall. After installing a bag body made of a pressure tube, filling the inside of the bag body with a relatively low primary injection material, and filling between the flank of the pile support work and the pile wall The secondary retaining material having a relatively high fluidity is pressurized and injected through the mountain retaining wall pressurizing tube, and the mountain retaining wall is pressurized by expanding the mountain retaining wall pressurizing tube so that the diameter is expanded. A construction method of a mountain retaining support is provided.
[0011]
As the present invention according to claim 3, a construction method for installing a mountain retaining support on a mountain retaining wall with ground excavation,
A bag body comprising a bag body and a mountain wall pressurizing tube which is provided between the end portions inside the bag body and does not have an open portion is installed between the upright of the mountain support work and the mountain retaining wall. And filling the space between the bag body and the retaining wall pressurizing tube with a primary injection material having relatively low fluidity, and filling the space between the erection of the retaining structure and the retaining wall. The pressure retaining wall is pressurized by injecting a relatively fluid secondary injection material into the retaining wall pressurizing tube and expanding the retaining wall pressurizing tube so that the diameter increases. There is provided a method for constructing a mountain retaining structure characterized in that it is performed.
[0012]
According to a fourth aspect of the present invention, there is provided the construction method of the mountain support structure according to any one of the second and third aspects, wherein the primary injection material is a curable material and the secondary injection material is a fluid material. The
[0013]
In the present invention described in claims 2 to 4, a tube for pressurizing the retaining wall is provided inside the bag body, and the primary is relatively low in fluidity for the padding between the erection of the retaining structure and the retaining wall. After the injection material was injected, the secondary injection material having relatively high fluidity for pressurizing the retaining wall was pressurized and injected through the tube for pressurizing the retaining wall. Therefore, the pressurization of the retaining wall can be performed uniformly.
[0014]
As the present invention according to claim 5, there is provided the construction method of the mountain support structure according to any one of claims 1 to 4, wherein the pressurization of the mountain retaining wall gives a pressure of 0.4 MPa or more. By simply filling or injecting a flowable material into the bag body, only a pressure state of about 0.05 to 0.1 MPa can be expected, but in order to replace the bag body with a jack, the pressure applied to the retaining wall is a pressure of 0.4 MPa or more. By performing the pressure injection of the flowable material so as to become, it becomes sufficient as a preload that achieves the object of the present invention.
[0015]
The present invention according to claim 6 is characterized in that it is made of a woven fabric having a small elastic elongation and a predetermined tensile strength, and a valve is provided at an end of at least one side of the water-proof bag. A bag for the construction method of the described mountain retaining support is provided.
[0016]
As the present invention according to claim 7, the bag body is provided inside the bag body , has a predetermined length from one end of the bag body, the other end opening faces the bag body, and the diameter is bag for earth retaining shoring method construction according to any one of claims 2-5, characterized in that it consists of a earth retaining wall pressurizing tube for performing pressurization of earth retaining wall by swelling to enlarge Is provided.
[0017]
As the present invention according to claim 8, the bag body and the inside of the bag body, a predetermined length from one end of the bag body, the other end opening facing the bag body , the diameter is It is composed of a mountain retaining wall pressurizing tube that pressurizes the retaining wall by expanding so as to expand, and provided with a valve that opens and closes a communication path into the mountain retaining wall pressurizing tube on at least one end side. The bag body for the construction method of the mountain retaining support in any one of Claim 2, 4, 5 characterized by the above-mentioned is provided.
[0018]
As the present invention according to claim 9, the bag body is installed inside the bag body, has a predetermined length from one end of the bag body, the other end opening faces the bag body, and the diameter is It consists of a mountain retaining wall pressurizing tube that pressurizes the retaining wall by expanding so as to expand, and opens and closes a communication path to the space between the bag body and the retaining wall pressurizing tube on one end side. And a double structure valve for opening and closing the communication path into the mountain retaining wall pressurizing tube. The body is provided.
[0019]
As the present invention according to claim 10, pressurization of the retaining wall by swelling the bag body and the inside of the bag body between the end portions without having an open portion and expanding the diameter. A retaining wall pressurizing tube that opens and closes a communication path to the space between the bag body and the retaining wall pressurizing tube on one end side, and a communication path into the retaining wall pressurizing tube. 6. A bag body for a construction method of a mountain retaining support according to claim 3, further comprising a double structure valve that opens and closes.
[0020]
As the present invention according to claim 11, there is provided the bag according to any one of claims 7 to 10, wherein the bag is made of a woven fabric having a small elastic elongation and a predetermined tensile strength, and has a water shielding property.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0022]
The retaining walls targeted by the main retaining structure include steel sheet piles such as sheet piles and steel pipe sheet piles, as well as column types such as soil cement column walls, RC column walls, and steel pipe column walls. Various retaining walls such as mountain retaining walls, cast-in-place RC underground walls, PC board ground walls and various pile retaining walls such as main pile side sheet piles can be targeted. There are uplifting / cut-beam-type mountain retaining supports and anchor-type retaining-type support structures, but the former abdominal raising / cut-beam-type retaining structures (including cases where only the upright is supported) or both are used in combination. It can be used for mountain retaining works.
[0023]
As shown in FIG. 1, the above-mentioned erection / cut-beam type retaining support is fixed to a retaining wall 1 with a bracket 2 or the like by welding or the like, and a bag receiving plate is horizontally mounted on the brackets 2, 2. At the same time, if the uprising 3 was laid horizontally, the internal air was extracted and deflated between the uprising 3 and the mountain retaining wall 1 in order to absorb the alignment of the earth retaining wall and to absorb unevenness. The filling / pressurizing bag body 5 (hereinafter, simply referred to as a bag body) is inserted, and the upright is erected and the beam 4 is horizontally placed between 3 and 3 to assemble the support. The bag body 5 may be located on the back side of the upset 3 and may be attached to the upset 3 in advance.
[0024]
When the operation up to this point is completed, by pressurizing and injecting a fluid material into the bag body 5, the padding between the flank 3 and the retaining wall 1 of the retaining support and the retaining wall 1 1 is continuously performed. Here, “continuous” refers to both the case where both processes are performed almost simultaneously without any time between filling and pressurization, and the case where pressurization is performed after a certain period of time. means. That is, it means that the pressurization process can be performed continuously without requiring any preparatory work for pressurization after the stuffing process. As the fluid material, for example, a liquid such as water or muddy water, or a curable material such as mortar or concrete, any material can be used as long as it is incompressible and exhibits fluidity at least when injected. Can do.
[0025]
The bag body 5 has flexibility (easily deformable), and a bag body that swells as the fluid material is injected into the inside is used, but the material is highly elastic like rubber. In the case of showing elongation, even if a fluid material is injected into the inside, the pressure escapes while inflating the non-restraining side, in this case the top and bottom sides, and the pressure efficiency is poor. For example, synthetic fiber fabric or glass fiber fabric A material having a small elastic elongation and a material having a predetermined tensile strength and having a coating for providing a water shielding function is preferably used. In addition to the circular cross section shown in FIG. 2, the cross-sectional shape can be any cross-sectional shape as long as the retaining wall surface side can be efficiently pressurized in a bulging state, such as a vertically long rectangular cross section.
[0026]
As shown in FIGS. 2 and 3, the structure of the bag body 5 is provided with opening and closing valves 6 and 7 at both ends, respectively, and one side of these opening and closing valves 6 and 7 is used as an inlet for the fluid material. The other side is used as an air vent hole. More specifically, a fluid material supply hose is connected to the opening / closing valve 6 side, and the other opening / closing valve 7 has an open cock 7a to serve as an air discharge path. The cock 6a is opened and the fluid material sent by the pressure pump is injected into the bag body 5. After that, when it is confirmed that the fluid material is discharged from the opening / closing valve 7, the cock 7a is closed. When pressurizing the retaining wall 1 continuously, the fluid 6 is continuously injected until a predetermined pressure is reached, and then the cock 6a is closed. Whether or not the predetermined pressure has been reached can be confirmed, for example, by inserting an axial force meter in the middle of the beam 4 and measuring it. In this case, it is preferable that the pressure applied to the retaining wall 1 is a pressure of 0.4 MPa or more.
[0027]
By the way, when a relatively viscous mortar, concrete, or the like is used as the fluid material, according to experiments by the inventors, the pressure on the injection side is relatively high depending on conditions, and gradually increases as the distance increases. It was found that the applied pressure decreased. As a result, it has been found that in order to secure a predetermined pressure on the far side, the pressure in the vicinity of the injection side becomes excessively high and wasteful. Therefore, in the present invention, in order to eliminate such a bias of the applied pressure, as shown in FIG. 4, a double bag body 8 having a retaining wall pressurizing tube 9 inside is proposed.
[0028]
The first example of the double bag 8 shown in FIG. 4 includes a flexible bag 5 and an internal opening in the bag 5 and a predetermined length from one end and the other end opening. 9a is provided with a retaining wall pressurizing tube 9 facing the inside of the bag body 5, provided with a valve 10 for opening and closing a communication path into the retaining wall pressurizing tube 9 on one end side, and on the other end side The valve 11 is configured to open and close the communication path into the bag body 5.
[0029]
First, with the other side opening / closing valve 11 opened to form an air vent hole, the space portion between the bag body 5 and the mountain retaining wall pressurizing tube 9 has a relatively high viscosity through the mountain retaining wall pressurizing tube 9. Alternatively, a curable material such as concrete is filled (primary injection), and the space between the erection 3 and the retaining wall 1 of the retaining support is performed. If it is confirmed that the curable material is discharged from the opening / closing valve 11 side, the cock 11a is closed. Subsequently, following the filling step, a fluid material having a relatively low viscosity, such as water, mortar having a high water-cement ratio, cement milk, or the like is pressurized and injected through the mountain retaining wall pressurizing tube 9 (secondary injection). Then, pressurization to the retaining wall is performed while equalizing the applied pressure. By the secondary injection, the retaining wall pressurizing tube 9 swells so as to increase in diameter, so that the bag body 5 swells and generates a pressure force evenly in the longitudinal direction. The primary injection of the curable material may be performed from the opposite opening / closing valve 11 side. Further, when the pressure of the mountain retaining wall pressurizing tube 9 reaches a certain level or more, the whole can be uniformly pressurized so that the secondary injection material oozes from the wall surface of the tube.
[0030]
Next, as a second aspect, the double bag 8 ′ shown in FIG. 5 has the same bag structure, and is connected to the space between the bag 5 and the retaining wall pressurizing tube 9 on one end side. A double structure valve 12 for opening and closing the passage and opening and closing the communication passage into the tube 9 is provided, and a communication passage to the space between the bag body 5 and the retaining wall pressurizing tube 9 is provided on the other end side. It has a structure including a valve 11 that opens and closes.
[0031]
First, with the other side opening / closing valve 11 opened to form an air vent hole, a space portion between the bag body 5 and the retaining wall pressurizing tube 9 is filled with a curable material such as mortar or concrete (primary injection). Then, after the gap between the flank 3 of the mountain retaining support and the mountain retaining wall 1 is performed, and subsequently to the space filling step, through the tube 9 for pressurizing the retaining wall, for example, water to water cement ratio A large mortar or the like is pressurized and injected (secondary injection) to pressurize the retaining wall while equalizing the applied pressure. By the secondary injection, the retaining wall pressurizing tube 9 swells so as to expand in diameter, so that the bag body 5 swells and generates a uniform pressure in the longitudinal direction. The material is injected around the other end opening 9a of the retaining wall pressurizing tube 9, and the applied pressure on the other end 9a side of the retaining wall pressurizing tube 9 is increased. The applied pressure can be equalized.
[0032]
Furthermore, as shown in FIG. 6, the double bag 13 according to the third embodiment includes a flexible bag 5 and an open portion provided between the ends of the bag 5 within the bag 5. A retaining wall pressurizing tube 14 that does not have an opening, and opens and closes a communication path to the space between the bag body 5 and the retaining wall pressurizing tube 14 on one end side, and into the retaining wall pressurizing tube 14. A double structure valve 12 for opening and closing the communication path is provided, and a valve 15 for opening and closing the communication path to the space between the bag body 5 and the retaining wall pressurizing tube 14 is provided on the other end side. . The open / close valve on the other end may be a double structure valve 12.
[0033]
In the case of such a double bag 13, the cock 12 a of the double structure valve 12 is first opened with the other side opening / closing valve 15 opened to form an air vent hole, and the bag 5 and the retaining wall pressurizing wall are pressed. A communication path to the space with the tube 14 is opened, and a space portion between the bag body 5 and the retaining wall pressurizing tube 14 is filled (primary injection) with a curable material such as mortar or concrete. Thereafter, when it is confirmed that the primary injection material has been discharged from the open / close valve 15, the open / close valve 15 is tightened, and when the primary injection material is filled in the bag body 5, the cock 12a of the double structure valve 12 is closed, and the pile support is supported. Complete the padding between the erection 3 of the craft and the retaining wall 1. Next, the cock 12b of the double structure valve 12 is opened, a communication path to the retaining wall pressurizing tube 14 is opened, and water, a mortar having a high water cement ratio, or the like is pressurized in the retaining wall pressurizing tube 14. Injection (secondary injection) is performed to pressurize the retaining wall while equalizing the applied pressure.
[0034]
After completing the gap between the abdomen and the retaining wall and pressurizing the retaining wall by the above procedure, leave it for a few minutes and check whether the applied pressure has decreased. Re-inject accordingly. This re-injection can be performed at any time when the pressure applied to the retaining wall is lowered. The pressure injection of the fluid material into the bags 5, 8... May be performed only on one side of the flank facing the struts or simultaneously on both sides of the flank facing each other. You may make it perform. Furthermore, for example, when a support is installed at the lowermost stage in conjunction with excavation, a slight displacement of the retaining wall 1 may cause loosening (decrease in pressure) in the upper support. In order to prevent such a decrease in the applied pressure, re-pressure injection may be performed simultaneously with the pressure injection of the newly installed support in one or more stages on the upper side.
[0035]
Incidentally, in the above example, the bag 5 and the double bag 8 and 13 are used to press the mountain retaining wall together with the space between the abdomen and the mountain retaining wall. You may make it pressurize the retaining wall 1 while interposing a pressure jack and using this pressure jack together. Moreover, about the said bag body, it can also be set as the outer shape matched with the mountain retaining wall surface shape. For example, as shown in FIG. 7, when the sheet piles 20, 20... Having a U-shaped cross section are used, the retaining wall surface becomes an uneven surface. It can also be set as the irregularly shaped bead-like bag body 21 in which the cross-sectional portions 21b are alternately arranged.
[0036]
【The invention's effect】
As described above in detail, according to the present invention, it is possible to eliminate the installation work of the formwork and the like and to save labor, and it is possible to omit the preload introduction means such as a jack. In addition, it is possible to efficiently perform the process from padding of the retaining wall and the erection to the introduction of the preload, and various advantages such as being able to easily perform re-pressurization accompanying a decrease in axial force. It will have.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a main part of a mountain retaining support according to the present invention.
FIG. 2 is a perspective view of a bag body 5. FIG.
FIG. 3 is a longitudinal sectional view thereof.
FIG. 4 is a longitudinal sectional view of a double bag body 8 according to the first embodiment.
FIG. 5 is a longitudinal sectional view of a double bag 8 ′ according to a second embodiment.
FIG. 6 is a longitudinal sectional view of a double bag body 13 according to a third embodiment.
FIG. 7 is a view showing a modified example of the outer shape of the bag.
FIG. 8 is a perspective view of a main part of a conventional beam-and-raise type mountain retaining support.
FIG. 9 is a diagram showing how to set up the abdomen and the cutting beam.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Mountain retaining wall, 2 ... Bracket, 3 ... Raised, 4 ... Cross beam, 5 ... Bag body, 8 * 8 '* 13 ... Double bag body, 6 * 7 * 11 * 15 ... Open / close valve, 12 ... Double structure valve, 9 · 14 ... Tube for pressurizing the retaining wall

Claims

It is a construction method for installing a mountain retaining support on the retaining wall with ground excavation,
A bag body having a small elastic elongation and having a predetermined tensile strength and having a water-impervious property is installed between the erection of the mountain retaining support and the mountain retaining wall, and a fluid material is placed inside the bag body. A method for constructing a mountain retaining structure, comprising performing filling between the erection of the mountain retaining structure and the retaining wall and pressurizing the retaining wall by injecting under pressure.

It is a construction method for installing a mountain retaining support on the retaining wall with ground excavation,
A bag body and a mountain retaining wall provided inside the bag body and having a predetermined length with the other end opening facing the inside of the bag body between the upright of the mountain retaining support and the mountain retaining wall. After installing a bag body made of a pressure tube, filling the inside of the bag body with a relatively low primary injection material, and filling between the flank of the pile support work and the pile wall The secondary retaining material having a relatively high fluidity is pressurized and injected through the mountain retaining wall pressurizing tube, and the mountain retaining wall is pressurized by expanding the mountain retaining wall pressurizing tube so that the diameter is expanded. The construction method of the mountain retaining support characterized by this.

It is a construction method for installing a mountain retaining support on the retaining wall with ground excavation,
A bag body comprising a bag body and a mountain wall pressurizing tube which is provided between the end portions inside the bag body and does not have an open portion is installed between the upright of the mountain support work and the mountain retaining wall. And filling the space between the bag body and the retaining wall pressurizing tube with a primary injection material having relatively low fluidity, and filling the space between the erection of the retaining structure and the retaining wall. The pressure retaining wall is pressurized by injecting a relatively fluid secondary injection material into the retaining wall pressurizing tube and expanding the retaining wall pressurizing tube so that the diameter increases. A construction method of a mountain retaining work characterized by performing.

The construction method of the mountain retaining support according to claim 2, wherein the primary injection material is a curable material, and the secondary injection material is a fluid material.

The construction method of the mountain retaining support according to any one of claims 1 to 4, wherein the pressure of the mountain retaining wall is a pressure of 0.4 MPa or more.

The construction method of a mountain retaining support according to claim 1, wherein the method comprises a woven fabric having a small elastic elongation and a predetermined tensile strength, and a valve is provided on at least one side end of the water-proof bag. For the bag.

A bag body, and a bag body, which is provided inside the bag body , has a predetermined length from one end of the bag body, has the other end opening facing the bag body, and bulges to expand in diameter. bag for earth retaining shoring method construction according to any one of claims 2-5, characterized in that it consists of a earth retaining wall pressurizing tube for performing pressurization of earth retaining walls.

A bag body, and a bag body, which is provided inside the bag body, has a predetermined length from one end of the bag body, has the other end opening facing the bag body, and bulges to expand in diameter. It consists of a earth retaining wall pressurizing tube for performing pressurization of earth retaining wall, according to claim 2 and 4, characterized in that it comprises a valve for opening and closing a communication passage to at least one end side of the earth retaining wall pressurizing the tube, The bag for the construction method of the mountain retaining support according to any one of 5.

A bag body, and a bag body, which is provided inside the bag body, has a predetermined length from one end of the bag body, has the other end opening facing the bag body, and bulges to expand in diameter. A retaining wall pressurizing tube that pressurizes the retaining wall, and opens and closes a communication path to the space between the bag body and the retaining wall pressurizing tube on one end side, and the inside of the retaining wall pressurizing tube A bag body for a construction method of a mountain retaining support according to any one of claims 2, 4, and 5, further comprising a double-structure valve that opens and closes the communication path.

From the bag body, and a mountain retaining wall pressurizing tube that pressurizes the retaining wall by bulging so as to expand in diameter without having an open portion provided between the end portions inside the bag body. And a double-structure valve for opening and closing the communication path to the space between the bag body and the retaining wall pressurizing tube and opening and closing the communication path into the retaining wall pressurizing tube. The bag for the construction method of the mountain retaining support according to any one of claims 3, 4, and 5.

The bag body according to any one of claims 7 to 10, wherein the bag body is made of a woven fabric having a small elastic elongation and a predetermined tensile strength, and has a water shielding property.