JP3651342B2

JP3651342B2 - Water stop structure of steel sheet pile joint

Info

Publication number: JP3651342B2
Application number: JP2000022559A
Authority: JP
Inventors: 正浩野路; 智恒小磯; 啓眞中野
Original assignee: Sumitomo Metal Industries Ltd
Current assignee: Nippon Steel Corp
Priority date: 2000-01-31
Filing date: 2000-01-31
Publication date: 2005-05-25
Anticipated expiration: 2020-01-31
Also published as: JP2001214435A

Description

【０００１】
【発明の属する技術分野】
本発明は、通常の鋼矢板以上に止水性が要求される場合に用いられる鋼矢板の継手部の止水構造に関するものである。
【０００２】
【従来の技術と発明が解決しようとする課題】
地下構造物の建設における土留め壁や港湾・水域施設建設時における仮締切り等おいて鋼矢板が多く用いられている。この理由として、鋼材という高品質材料による高剛性壁体が比較的短い施工期間内で構築することができる他、比較的止水性に優れることが挙げられる。
【０００３】
鋼矢板本体の鋼材自体は当然ながら完全に水を通さないが、嵌合状態の継手部分に存在する隙間部分が水を通すため、この継手部分の隙間が鋼矢板の止水性に大きく影響する。一般的には、打設直後の継手部は比較的水を通し易い状態であったとしても、時間の経過に伴い、水の流れと共に継手内部に土粒子等が詰まってくるため、止水性が向上していくものであるが、土粒子等による継手内部の目詰まりが期待できない場合や、より止水性を向上させるためには、この継手内部の隙間をできる限り小さくすることも一案として考えられる。
【０００４】
しかしながら、この隙間が小さ過ぎると、継手部分での打設抵抗が非常に大きくなるという問題を有しており、止水性と施工性は相反する要求性能となるため、一概に継手部分の隙間を小さくしたり、大きくしたりすることはできず、いかにして継手部の止水性を高めるかが大きな課題の一つであった。
【０００５】
そこで、従来技術の一例として、継手内部の隙間を埋めるべく、予め鋼矢板の継手部に止水用樹脂塗料を塗布するものが挙げられる。この場合、比較的透水係数が小さい樹脂塗料によって、継手内部の水の浸透経路を塞いでしまうことで、止水性を向上させることを期待したものである。
【０００６】
その他としては、継手部付近において設けられた止水部材により形成したグラウト注入空間を有する鋼矢板が挙げられる。この場合、この注入空間内を止水性の高い材料をもって充填してしまうことで、止水性を高めるものである。
【０００７】
(1) 鋼矢板継手部に予め止水樹脂塗料を塗布する技術は、特開平１−１６８７６６号公報に開示されており、鋼矢板打設前に、比較的透水係数の小さい樹脂塗料を継手部内の隙間に塗布し、打設後に、周囲の水分を吸収した樹脂が膨張し、継手部内部が樹脂にて満たされることで止水性を高めるものである。しかしながら、打設前の継手部内へ樹脂塗料を塗布する際の塗布むらや打設時の樹脂塗料の塗膜損傷等の不可避的要素により止水性が低下する場合が挙げられる。このように欠損部分が発生した場合には、欠損箇所が比較的小さくとも、欠損部分での水の流速は比較的速くなるため、流れによる欠損箇所の拡大の恐れもある。
【０００８】
(2) グラウト注入空間を設けた従来技術として、以下に示すものがある。
(2-1) 特開平１−２８０１２２号公報
図９に示すように、嵌合される２つの矢板５０と５１の各継手部部位の一方または両方に部材５２を設け、この部材５２により矢板５０，５１間にグラウト注入空間５３を形成している。この鋼矢板では、グラウト注入空間が相互の継手の嵌合により形成され、継手により空間が完全に閉合されているため、止水性は高いと考えられるが、継手形状が非常に複雑なため、製造コストが高くなるという欠点がある。また、止水性が高い一方で継手部の余裕がないことに起因する施工性の悪化という前述した欠点が改善されていない。さらに、この継手形状では、施工延長が曲線状となっている場合等において、２カ所による嵌合のために各鋼矢板を継手部にて角度を付けながら曲線状に施工することは実質不可能であり、実用に供しないと考えられる。
【０００９】
(2-2) 特開平１−２８０１２1 号公報
図１０に示すように、既存の矢板の継手部分の一方の外側に耳プレート５４の一端部を溶接で接合し、他方の矢板の腹部との間にグラウト注入空間５３を形成している。この鋼矢板では、鋼矢板打設時において、捩じれや回転か発生すると耳プレートの接合していない部分で、耳プレートと隣接の鋼矢板との間が大きく開くことが考えられる。この場合には、本来の耳プレートの役割としては、グラウトの型枠を兼ねて、耳プレートと鋼矢板間の開口が小さいことによる止水効果を期待できるはずであるが、開口部分の増加により、止水性が低下するだけでなく、場合によっては、周囲の地盤からの内部への土の侵入等により、グラウト材品質が悪化する恐れが挙げられる。
【００１０】
(2-3) 実開昭５５−７１７４５号公報
図１１に示すように、Ｕ形鋼矢板６０の継手部付近に断面カギ形，半円形等の突片６１を設け、掘削機・注入機の先端が入る大きさの注入空間６２を形成している。この鋼矢板では、突片の先端が隣接するＵ形鋼矢板の爪底部に近い位置に位置するため、鋼矢板の回転等による開きの恐れはないが、実際にはＵ形鋼矢板の爪底部分の大きさは僅か２〜３ｃｍ程度しかなく、爪のサイズに合わせた特殊な部材を取り付ける必要があり、コスト的に劣るという欠点の他、突片と鋼矢板の間にできる隙間が継手部に近い位置にあるため、水の浸透経路は比較的短く、止水効果が発揮し難いという問題も有する。
【００１１】
本発明は、以上のような問題点を解消すべくなされたもので、その目的は、比較的簡単な構成により、要求される打設性および止水性の両者を満足させることのできる鋼矢板継手部の止水構造を提供することにある。
【００１２】
【課題を解決するための手段】
通常、鋼矢板の継手部は、施工性を考慮して、嵌合状態でも若干の隙間ができるように形状が設定されている。よって、止水部材と鋼矢板あるいは止水部材同士の間に隙間が生じないように止水部材を設けたとしても、前記の継手部の嵌合状態に応じて、この隙間分だけ鋼矢板がずれ、止水部材と鋼矢板あるいは止水部材同士の間には、どうしても隙間が生じてしまう。
【００１３】
そこで、本発明の請求項１の鋼矢板継手部の止水構造では、図１(a) に示すように、鋼矢板１，１の継手部２，２同士を嵌合させた際に、一部が重なり合う一対の止水部材３，３により鋼矢板継手部２を覆う閉合空間４が形成されるように、鋼矢板１に止水部材３が設けられていることを特徴とする。なお、止水部材３は鋼矢板１のフランジ部分における内面または外面に溶接等で接合する。
【００１４】
即ち、止水部材同士の間に隙間が生じることを前提として、この隙間を鋼矢板の打設性を阻害しないための余裕代として許容すると共に、鋼矢板が捩じれたり、回転したりした場合においても、止水部材によって形成される閉合空間に開口部が発生しないよう配慮したものである。さらには、止水部材同士を一部重ね合わせたことで、重ね合わせた部分による止水効果をも得られるようにしたものである。
【００１５】
この重ね合わせの効果について以下に説明する。図１(a) ，(b) はいずれも、Ｕ型鋼矢板１の継手部２の近傍に止水部材３の基端を取り付け、一対の止水部材３，３により継手部が覆われるように閉合空間４を形成したものである。図１の(a) と(b) の差異は、一対の止水部材３，３が重なり合っているかどうかのみであり、この止水部材間の開口部（隙間）をδ、重なり合っている止水部材３の重ね合せ長をＬとする。また、鋼矢板１の挟んだ内外の水頭差をｈとする。
【００１６】
ここで、透水に関する一般式であるダルシーの法則を次の（１）式に示す。
Ｑ＝ｋ・Ａ・ｉ＝ｋ・Ａ・Ｈ／Ｌ……（１）
ここに、ｋは透水係数、Ａは透過面積、ｉは動水勾配（＝水頭差Ｈ／距離Ｌ）である。
【００１７】
つまり、透水量Ｑは、透水係数・透過面積・動水勾配に比例するのである。図１(b) の条件の場合、一対の止水部材３，３で形成された閉合空間４内に透水係数ｋの土砂５が詰まっている状態で、透水量がＱ_bであったものとする。
一方で、図１(a) の場合においては、さらに、止水部材３の重なり合う部分の隙間にも透水係数ｋの土砂５が詰まっている状態とし、ａ点とｃ点との水頭差をΔｈとすると、ａ−ｃ間では、式（１）中において水頭差Ｈを除いて図１(b) の場合と同一の条件となるので、図１(b) の場合の透水量Ｑ_bより、Ｑ_a＝Ｑ_b・（Δｈ／ｈ）となる。ここで、Δｈ＜ｈであれば、Ｑ_a＜Ｑ_bとなる。
【００１８】
次に、この止水部材３内を透過する流量Ｑ_aは、流体の連続性より、重なり合った止水部材間であるｃ−ｂ間でも同様の流量となるため、式（１）より、Ｑ_a＝ｋ・δ・（ｈ−Δｈ）／Ｌとなる。従って、ａ−ｃ間での水頭差は、Δｈ＝ｈ−Ｑ_a・Ｌ／（ｋ・δ）となり、少なくとも、図１(b) に比べ、水頭差は小さくなる。
【００１９】
つまり、若干でも水の透過性を妨げる物質が、止水部材３が重なり合った部分において存在することで、ｃ点での水頭が落ち、結果として、ａ−ｃ間での水頭差（動水勾配）が小さくなるため、通水量を減少させることが可能となり、止水性が向上する。
【００２０】
また、請求項１では、止水部材３の鋼矢板１への接合方法や接合位置、一対の止水部材３，３の重なり合う部分の隙間量・重ね合せ長等は特に限定しない。止水部材３と鋼矢板１により形成される閉合空間内に位置する継手部は一つである必要はなく、例えば図２(c) に示すように止水部材３，３を一つおいた鋼矢板１Ａ，１Ａにそれぞれ接合し、閉合空間４内に２つの継手部２が位置するようにしてもよい。止水部材３の接合方法としては、接合部分から水の浸透がないように接合できるものが好ましい。鋼矢板１に止水部材３を予め設けておいてもよいし、継手となる接合部材を設けておき、止水部材３を打設するようにしてもよい。また、隙間量・重ね合せ長に関しては、施工性に配慮した上で、可能な限り、隙間量を小さくし、重ね合せ長を長くとることが望ましい。鋼矢板を土中に打設した場合には、止水部材の隙間の間に、時間の経過と共に土砂が詰まってくることが考えられ、この土砂の詰まりにより止水効果は高まると考えられるが、この隙間の状態についても、特に限定するものではなく、水の透過を妨げることができるものが詰まっているか、あるいは、詰まることが十分予測されるようにすればよい。
【００２１】
さらに、止水部材３の形状についても、特には限定しない。図１では、Ｌ形断面を有する止水部材を用いており、比較的容易に入手できる市販のアングル鋼材を用いることで、止水部材の材料費および加工費等のコストを低く抑えられると共に、止水部材同士の重なり合う部分が平行となるように配置することも容易である。図２(c) に示すように、直線状の止水部材とすることもできる。
【００２２】
止水部材３の重なり合う部分を平行とすることで得られる利点としては、図２(a) に示すように、継手部２の標準嵌合状態において止水部材３，３の先端部同士が完全に接するように止水部材３を鋼矢板１に接合した場合には、隙間が発生しない区間が面として存在するため、止水効果は非常に高くなる。図２(b) に示すように、前記の状態で止水部材３を鋼矢板１に接合し、鋼矢板１の打設時に鋼矢板継手部２の嵌合状態が標準よりずれた場合においても、鋼矢板継手部２の当接面隙間が狭まる分、止水部材３，３間の隙間量が増えるだけであり、その隙間量は高々鋼矢板嵌合時の継手部内部の隙間量程度に抑えられることが挙げられる。
【００２３】
その他の利点としては、この止水部材３をガイドとして、鋼矢板１を真っ直ぐ打設することも可能となるため、鋼矢板の回転や捩じれが発生し難く、つまりは、止水部材３，３に開口部が生じ難くなり、結果として止水性が向上することも挙げられる。
【００２４】
本発明の請求項２では、請求項１の鋼矢板継手部の止水構造において、図３に示すように、一対の止水部材３，３は、一部が鋼矢板継手部２を中心とする同心円弧状に重なり合う形状を有していることを特徴としており、鋼矢板継手部２を中心に鋼矢板１が回転した場合においても、一対の止水部材３，３の重なり合う部分が必ず平行となるようにしたものである。なお、円弧部分は少なくとも重なり合う部分に形成すればよい。
【００２５】
このようにすることで、継手部２を中心とした鋼矢板１の比較的大きな回転に対しても、止水部材３，３同士の接触を防ぐことができ、打設性の低下の恐れが無くなる。また、図３の点線で示すように、回転可能角度以上にわたって重ね合わせることで、施工時に止水部材３の重なり合う範囲が減少していく方向に回転した場合でも、止水部材３，３同士が重なり合う部分が必ず存在し、開口部の発生の恐れが無い。
【００２６】
請求項１の鋼矢板継手部の止水構造において、鋼矢板に接合される止水部材の位置関係を限定することで、鋼矢板の継手部を中心とした鋼矢板の施工中の回転に伴う開口部発生防止を考慮する場合には、図４に示すように、鋼矢板継手部２の中心位置を原点Ｏとし、一対の止水部材３Ａ，３Ｂのうち重なり部分が原点から遠い方の止水部材３Ｂの自由端部に原点Ｏから下ろした垂線をＹ軸（止水部材側を正方向とする）とし、これと直交する軸をＸ軸とした座標系において、重なり部分が原点から近い方の止水部材３Ａの自由端部の先端位置Ａを（ｘ1 ，ｙ1 ）、該止水部材３Ａの原点から最も離れた位置Ａ’を（ｘ1', ｙ1'）、重なり部分が原点から遠い方の止水部材３Ｂの自由端部の先端位置Ｂを（ｘ2 ，ｙ2 ）、ｙ1 ＜ｙ2 とした場合、ｘ1 ・ｘ2 ＜０、（ｘ1²＋ｙ1²）≧ｙ2²、（ｘ1'² ＋ｙ1'² ）≧（ｘ2²＋ｙ2²）を満足するように、止水部材３Ａ，３Ｂが鋼矢板１，１に設けられるようにする。
【００２７】
このように止水部材３Ａ，３Ｂが鋼矢板１，１にそれぞれ接合されていれば、図４(a),(b) に示すように、必ず、いずれかの止水部材の自由端部の先端が他の止水部材に点接触するため、鋼矢板継手部を中心とした鋼矢板の回転に伴う開口部発生が防止される。このように限定するためには、Ｙ軸を定義する垂線を一義に決める必要があり、少なくとも止水部材３Ａと３Ｂが重なり合っている部分のうち、止水部材１Ｂについては、直線状でなければならない。
【００２８】
この場合も、鋼矢板がいずれの方向に大きく回転した場合においても、重なり合う部分が必ず存在し、開口部が生じて止水性が低下する心配が無い他、接触したとしても、先端部分の点接触のみであるため、極端に打設性が低下することはなく、施工性・止水性という要求性能をいずれも満足させることが可能である。万が一、鋼矢板の回転に伴う接触により、打設性が低下する懸念がある場合には、止水部材を可撓性を有するものとすることで対処することも可能である。
【００２９】
本発明の請求項３は、請求項１または２の鋼矢板継手部の止水構造において、鋼矢板の形状および止水部材の取付位置を限定したものであり、図６，図７に１例を挙げて示すように、鋼矢板は、鋼矢板本体から左右に突出する一対の腕部１２，１２の先端にそれぞれ互いに嵌合可能な異なる形状の継手２，２’を有し、各鋼矢板が同一姿勢で（鋼矢板の向きを同じ方向にして）嵌合打設される鋼矢板１１であり、前記一対の腕部１２，１２のいずれか一方の面に止水部材３が設けられていることを特徴とする。なお、図６，図７の例では、継手部２，２’は、嵌合時に、継手部２’の甲面と腕部１２の外面が同一平面をなすような形状とされている。
【００３０】
図５に示す一般的な形状のＵ形鋼矢板１を使用した場合、止水部材３を外側の面に接合した鋼矢板１Ａと、内側の面に接合した鋼矢板１Ｂの２種類が必要となり、加工上や積み重ね上、輸送上、あるいは施工上の管理が複雑となり、場合によっては、積み重ねができない可能性がある。
【００３１】
これに対して、例えば図６(a) に示す形状の鋼矢板１１を使用した場合、図６(b),(c) 、図７に示すように、腕部１２の内外面のいずれか一方の面に止水部材３を接合することができるため、加工上や積み重ね上、輸送上、あるいは施工上の管理が容易となる利点が挙げられる。
【００３２】
この場合の止水部材３の接合パターンとしては、種々のものが考えられる。例えば、図６(b),(c) の場合は、左右の腕部１２にそれぞれ止水部材３Ａ，３Ｂが接合された１種類の鋼矢板１１を使用することができ、図７の場合は、左右の腕部１２に止水部材３Ａのみが接合された鋼矢板１１Ａと、左右の腕部１２に止水部材３Ｂのみが接合された鋼矢板１１Ｂの２種類を交互に使用することができる。
【００３３】
また、景観性に配慮しなければならない場合や腹起し材等の支保部材の取り付けのため、しっかりとしたフラット面が求められる場合は、前記の図６(b) ，図７に示したように、嵌合時において、継手部のために同一平面をなさない側に止水部材３を接合することで、止水部材３が接合されていない面がフラットとなるため、対応も容易である。
【００３４】
本発明の請求項４は、請求項１、２または３の鋼矢板継手部の止水構造において、図８に示すように、一対の止水部材３，３の重なり合う部分の隙間に止水シール材２０が設けられていることを特徴とする。
【００３５】
本発明の請求項５は、請求項１、２、３または４の鋼矢板継手部の止水構造において、図８に示すように、鋼矢板継手部内に止水シール材２０が設けられていることを特徴とする。
【００３６】
請求項４および５において、止水シール材としては、例えば、止水ゴムや水膨張性の樹脂塗料等が挙げられる。このような止水シール材を設けることで、更なる止水性向上を発揮することができる。
【００３７】
本発明の請求項６は、請求項１、２、３、４または５の鋼矢板継手部の止水構造において、図８に示すように、閉合空間内に止水性を有する材料３０が充填されていることを特徴とする。
【００３８】
止水性を有する材料としては、モルタル・コンクリート・ウレタン樹脂等が挙げられるが、これについても特に限定するものではない。このような材料を鋼矢板打設後に閉合空間内に投入することにより、更なる止水性向上を発揮することができる。
【００３９】
止水性を有する材料の投入に当たっては、鋼矢板打設後、閉合空間内に土砂が詰まっている場合には、これをウォータジェット等により取り除いた上で投入することができるが、土砂を取り除かなくとも、土砂内に浸透し、土砂と共に止水性を発揮する止水材料でも構わない。
【００４０】
【発明の実施の形態】
以下、本発明を図示する実施の形態に基づいて説明する。図１(a) は、Ｕ形鋼矢板に適用した例であり、Ｕ形鋼矢板１の左右両側におけるフランジ部分の内面あるいは外面に、継手部２と平行に配設したアングル鋼材からなる止水部材３の基端部を溶接等で接合している。この止水部材３の基端部をＵ形鋼矢板１のフランジ部分に対して直角に取り付けることにより、隣接する鋼矢板同士を継手部２で嵌合させた状態で、一対の止水部材３，３の自由端部同士が平行となる。さらに、一対の止水部材３，３の基端部の長さおよび自由端部の長さを適宜決定すれば、自由端部同士が隙間δをおいて平行に長さＬだけ重なり合う。
【００４１】
鋼矢板１の打設後、一対の止水部材３，３で囲まれた閉合空間４内および重なり合う自由端部同士の隙間に土砂５等が詰まり、図１(b) と比較して、内外の水頭差が小さくなり、透水量が減少することで、止水性が向上する。さらに、図２(a) に示すように、継手部２の隙間がδの標準嵌合状態で、一対の止水部材３，３の重なり合う自由端部同士が完全に面で接するようにすれば、止水効果は更に向上する。図２(b) に示す状態にずれたとしても、重なり合う自由端部同士の隙間はδとなり、止水性が十分に確保される。
【００４２】
また、鋼矢板１を打設する際に、一対の止水部材３，３の平行な自由端部がガイド部材として働くため、鋼矢板１を真っ直ぐに打設することができ、鋼矢板１の回転や捩じれを防止することができ、また回転や捩じれによる開口の発生が防止されることで、止水性の向上を図ることができる。
【００４３】
さらに、図４に示すように、一対の止水部材３，３の位置関係を限定することで、鋼矢板１の継手部２を中心とした鋼矢板施工中の回転による開口部の発生を防止することができる。即ち、内側の止水部材３Ａの点Ａ（ｘ₁，ｙ₁）および点Ａ’（ｘ₁', ｙ₁'）、外側の止水部材３Ｂの点Ｂ（ｘ₂，ｙ₂）が、ｘ₁・ｘ₂＜０、（ｘ₁ ²＋ｙ₁ ²）≧ｙ₂ ²、（ｘ₁'²＋ｙ₁'²）≧（ｘ₂ ²＋ｙ₂ ²）を満足するように、一対の止水部材３Ａ，３Ｂの形状・寸法等を適宜決定すれば、鋼矢板１が継手部２を中心として回転しても、止水部材３Ａの外面が止水部材３Ｂの内面に点接触するため、鋼矢板１の回転に伴う開口部発生が防止される。なお、外側の止水部材３Ｂの自由端部が直線状であれば、その他の部分は前述の条件を満足する限りどのような形状でも開口部発生を防止できる。
【００４４】
また、図５に示すように、鋼矢板１は、内側の止水部材３Ａを鋼矢板のフランジ部における外面に接合した鋼矢板１Ａと、外側の止水部材３Ｂを鋼矢板のフランジ部における内面に接合した鋼矢板１Ｂの２種類を用意し、これらを交互に打設すればよい。
【００４５】
次に、図３は止水部材３の形状を変えた例であり、一対の止水部材３，３を、鋼矢板継手部２の中心点Ｏを中心とし所定の隙間をおいた同心円弧状としている。この円弧状の止水部材３の基端部は滑らかに折り曲げて鋼矢板１のフランジ部分の内面あるいは外面に添接し溶接等で接合している。なお、止水部材３全体を円弧状に形成してもよいし、重なり合う部分のみを円弧状に形成するようにしてもよい。
【００４６】
この場合、アングル鋼材の場合と同様に、重なり合う自由端部により止水性が向上する。また、継手部２を中心とした鋼矢板１の比較的大きな回転に対しても、止水部材３，３同士の接触を防ぐことができ、打設性が低下することがない。さらに、回転可能角度以上にわたって重ね合わせることで、施工時に止水部材３の重なり合う範囲が減少していく方向に回転した場合でも、止水部材３，３同士が重なり合う部分が必ず存在し、開口部の発生の恐れが全く無い。
【００４７】
次に、図６，図７は、鋼矢板に、Ｕ形鋼矢板本体の左右両側に本体ウェブ部分と平行な直線状の腕部１２が一体的に突設され、この腕部１２，１２に互いに嵌合可能な異なる形状（左右非対称な形状）の継手部２，２’が設けられた鋼矢板１１を用いた例である。また、継手部２，２’は、嵌合時に、継手部２’の甲面と腕部１２の外面が同一平面をなすような形状である。
【００４８】
このような鋼矢板１１を使用した場合、図６(b),(c) 、図７に示すように、腕部１２の内外面のいずれか一方の面に止水部材３を接合することができるため、加工上・積み重ね上・輸送上・施工上の管理等が容易となる。また、図６(b),(c) の場合は、左右の腕部１２にそれぞれ止水部材３Ａ，３Ｂが接合された１種類の鋼矢板１１を使用することができる。図７の場合は、左右の腕部１２に止水部材３Ａのみが接合された鋼矢板１１Ａと、左右の腕部１２に止水部材３Ｂのみが接合された鋼矢板１１Ｂの２種類を交互に使用することができる。さらに、図６(b) および図７の場合、腕部１２に止水部材のないフラットな表面が形成されるため、景観性に配慮しなければならない場合や腹起し材等の支保部材の取り付ける場合に容易に対応することができる。
【００４９】
次に、図８は本発明の一対の止水部材３，３による止水性能を一段と高める手段を示したものであり、一対の止水部材３，３の重なり合う部分の隙間および一対の継手部２，２内に、止水ゴムや水膨張性の樹脂塗料等の止水シール材２０を設ける。また、閉合空間４内にモルタル・コンクリート・ウレタン樹脂等の止水性を有する材料３０を打設後に投入し充填する。この場合、鋼矢板打設後、閉合空間４内に詰まっている土砂をウォータジェット等により取り除いた上で投入する。土砂内に浸透し、土砂と共に止水性を発揮する止水材料の場合には、土砂は取り除かなくてもよい。
【００５０】
なお、本発明は図示した形状の鋼矢板に限定されることなく、その他の形状の鋼矢板にも適用できることは言うまでもない。
【００５１】
【発明の効果】
本発明は、以上のような構成からなるので、次のような効果を奏することができる。
(1) 一対の止水部材の自由端部同士を重ね合わせているため、重ね合わせた部分により透水量を低減することができると共に、鋼矢板が回転したり捩じれたりした場合にも隙間が発生することがなく、比較的簡単な構成の止水部材により、止水性を大幅に向上させることができる。
(2) さらに、一対の止水部材の重ね合わせた部分は隙間が生じることを前提としているため、鋼矢板の打設性を阻害することがなく、打設性と止水性の両方を同時に満足させることができる。
(3) 一対の止水部材の位置関係を限定することにより、あるいは一対の止水部材を同心円弧形状とすることにより、打設時に鋼矢板が継手を中心として回転しても、開口部の発生の恐れが全く無く、十分な止水性能を確実に得ることができる。
(4) 一対の止水部材の重なり合う部分の隙間および一対の継手部内に止水シール材を設け、あるいは閉合空間内に止水性を有する材料を充填することにより、一対の止水部材による止水性能を一段と高めることができる。
(5) 鋼矢板に、鋼矢板本体から左右に突出する一対の腕部の先端にそれぞれ互いに嵌合可能な異なる形状の継手を有し、各鋼矢板が同一姿勢で嵌合打設される鋼矢板を使用することで、前記一対の腕部のいずれか一方の面に一対の止水部材を設けることができ、加工上・積み重ね上・輸送上・施工上の管理等が容易となる。
【図面の簡単な説明】
【図１】本発明の鋼矢板継手部の止水構造の１例を示す平面図であり、(a) は本発明例、(b) は比較例である。
【図２】本発明の鋼矢板継手部の止水構造の鋼矢板打設後の状態を示す平面図であり、(a) は標準嵌合状態、(b) は標準からずれた状態を示す。(c) は図１の止水構造の他の例を示す平面図である。
【図３】本発明の鋼矢板継手部の止水構造の止水部材の形状が異なる例を示す平面図である。
【図４】図１の止水部材における開口防止を説明するための平面図である。
【図５】図１の鋼矢板の配列状態を示す平面図である。
【図６】本発明の止水構造に適用される鋼矢板の他の例とその配列状態を示す平面図である。
【図７】図６の鋼矢板の止水部材の取付け方法が異なる場合を示す平面図である。
【図８】本発明の止水構造において止水性能をより向上させる手段を示す平面図である。
【図９】従来の止水用鋼矢板（その１）を示す平面図である。
【図１０】従来の止水用鋼矢板（その２）を示す平面図である。
【図１１】従来の止水用鋼矢板（その３）を示す平面図である。
【符号の説明】
１…鋼矢板
２…継手部
３…止水部材
４…閉合空間
５…土砂
１１…鋼矢板
１２…腕部
２０…止水シール材
３０…止水性を有する材料[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a water stop structure of a joint portion of a steel sheet pile used when water stop is required more than a normal steel sheet pile.
[0002]
[Prior art and problems to be solved by the invention]
Steel sheet piles are often used for retaining walls in the construction of underground structures and temporary cut-offs during the construction of harbors and water facilities. The reason for this is that a high-rigidity wall made of a high-quality material such as steel can be constructed within a relatively short construction period, and has a relatively excellent water-stopping property.
[0003]
Of course, the steel sheet itself of the steel sheet pile main body does not allow water to pass through completely, but since the gap portion existing in the joint portion in the fitted state allows water to pass therethrough, the gap of this joint portion greatly affects the water stoppage of the steel sheet pile. In general, even if the joint part immediately after placing is relatively easy to pass water, as the time passes, soil particles and the like are clogged inside the joint with the flow of water, However, if the clogging inside the joint due to soil particles cannot be expected, or in order to further improve the water-stopping, it is considered to make the gap inside the joint as small as possible. It is done.
[0004]
However, if this gap is too small, there is a problem that the casting resistance at the joint part becomes very large, and the water stoppage and workability are contradictory performance requirements. It was not possible to make it smaller or larger, and one of the major issues was how to increase the water stoppage of the joint.
[0005]
Then, as an example of a prior art, what fills the joint part of a steel sheet pile previously with the resin coating for water stop is mentioned in order to fill the clearance gap inside a joint. In this case, it is expected that the water stoppage is improved by blocking the water permeation path inside the joint with a resin paint having a relatively small water permeability coefficient.
[0006]
Other examples include a steel sheet pile having a grout injection space formed by a water stop member provided in the vicinity of the joint. In this case, filling the inside of the injection space with a material having a high water-stopping property improves the water-stopping property.
[0007]
(1) A technique for applying a water-stopping resin paint to a steel sheet pile joint in advance is disclosed in JP-A-1-168766, and a resin paint having a relatively low permeability is applied to the joint before placing the steel sheet pile. The resin that has absorbed the surrounding moisture is expanded after being applied to the gap, and the inside of the joint is filled with the resin to increase the water-stopping property. However, there are cases where the water stoppage is lowered due to unavoidable factors such as coating unevenness when the resin paint is applied into the joint portion before placement and damage to the coating film of the resin paint at the time of placement. When a defect portion is generated in this way, even if the defect portion is relatively small, the flow rate of water at the defect portion is relatively high, and thus the defect portion may be enlarged due to the flow.
[0008]
(2) The following is a conventional technique provided with a grout injection space.
(2-1) JP-A-1-280122
As shown in FIG. 9, a member 52 is provided at one or both of the joint portions of the two sheet piles 50 and 51 to be fitted, and a grout injection space 53 is formed between the sheet piles 50 and 51 by the member 52. Yes. In this steel sheet pile, the grout injection space is formed by fitting the joints together, and the space is completely closed by the joints. There is a disadvantage that the cost becomes high. Moreover, the above-mentioned fault of the deterioration of workability resulting from not having a margin of a joint part while having high water-stopping properties has not been improved. Furthermore, with this joint shape, it is practically impossible to construct each steel sheet pile in a curved shape with an angle at the joint part for fitting in two places when the construction extension is curved. Therefore, it is considered that it will not be put to practical use.
[0009]
(2-2) JP-A-1-280121
As shown in FIG. 10, one end of the ear plate 54 is joined to one outer side of a joint portion of an existing sheet pile by welding, and a grout injection space 53 is formed between the other sheet pile abdomen. In this steel sheet pile, when twisting or rotating occurs during the steel sheet pile driving, it is conceivable that a gap between the ear plate and the adjacent steel sheet pile opens widely at a portion where the ear plate is not joined. In this case, the role of the original ear plate is to serve as a grout formwork and can be expected to have a water stop effect due to the small opening between the ear plate and the steel sheet pile. In addition to the deterioration of the water-stopping property, in some cases, there is a possibility that the quality of the grout material is deteriorated due to the invasion of soil from the surrounding ground.
[0010]
(2-3) Japanese Utility Model Publication No. 55-71745
As shown in FIG. 11, a protruding piece 61 having a cross-sectional key shape or a semicircular shape is provided in the vicinity of the joint portion of the U-shaped steel sheet pile 60 to form an injection space 62 having a size for receiving the tip of the excavator / injector. Yes. In this steel sheet pile, the tip of the projecting piece is located close to the nail bottom of the adjacent U-shaped steel sheet pile, so there is no fear of opening due to rotation of the steel sheet pile, but in reality the nail bottom of the U-shaped steel sheet pile The size of the part is only about 2 to 3 cm, and it is necessary to attach a special member according to the size of the nail. In addition to the disadvantage of being inferior in cost, there is a gap created between the protruding piece and the steel sheet pile. Therefore, the water permeation path is relatively short and it is difficult to exert a water stop effect.
[0011]
The present invention has been made to solve the above-mentioned problems, and its purpose is a steel sheet pile joint that can satisfy both required driving property and water stoppage with a relatively simple configuration. It is in providing the water stop structure of a part.
[0012]
[Means for Solving the Problems]
Usually, the shape of the joint portion of the steel sheet pile is set so that a slight gap is formed even in the fitted state in consideration of workability. Therefore, even if a water stop member is provided so that a gap does not occur between the water stop member and the steel sheet pile or between the water stop members, the steel sheet pile is equivalent to this gap according to the fitting state of the joint part. There is a gap between the water stop member and the steel sheet pile or the water stop member.
[0013]
Therefore, in the water stop structure of the steel sheet pile joint portion according to claim 1 of the present invention, as shown in FIG. 1 (a), when the joint portions 2, 2 of the steel sheet pile 1, 1 are fitted together, The steel sheet pile 1 is provided with a water stop member 3 so that a closed space 4 that covers the steel sheet pile joint portion 2 is formed by a pair of water stop members 3 and 3 that overlap each other. In addition, the water stop member 3 is joined to the inner surface or the outer surface of the flange portion of the steel sheet pile 1 by welding or the like.
[0014]
That is, on the premise that a gap is generated between the water stop members, this gap is allowed as a margin for not obstructing the placing performance of the steel sheet pile, and the steel sheet pile is twisted or rotated. Also, the opening is not generated in the closed space formed by the water stop member. Furthermore, the water-stopping member is partially overlapped so that the water-stopping effect by the overlapped portion can be obtained.
[0015]
The effect of this superposition will be described below. 1 (a) and 1 (b), the base end of the water stop member 3 is attached in the vicinity of the joint portion 2 of the U-shaped steel sheet pile 1 so that the joint portion is covered by the pair of water stop members 3 and 3. A closed space 4 is formed. The difference between (a) and (b) in FIG. 1 is only whether or not the pair of water-stopping members 3 and 3 overlap each other. The opening (gap) between the water-stopping members is δ, and the waterstops are overlapping. Let L be the overlapping length of the members 3. Further, the difference between the water head inside and outside the steel sheet pile 1 is h.
[0016]
Here, Darcy's law, which is a general formula related to water permeability, is shown in the following formula (1).
Q = k · A · i = k · A · H / L (1)
Here, k is a water permeability coefficient, A is a permeation area, and i is a hydraulic gradient (= water head difference H / distance L).
[0017]
That is, the water permeability Q is proportional to the water permeability coefficient, the permeation area, and the dynamic water gradient. In the case of the condition of FIG.1 (b), in the state where the earth and sand 5 of the permeability coefficient k are clogged in the closed space 4 formed of the pair of water blocking members 3 and 3, the water permeability is Q._bIt shall be.
On the other hand, in the case of FIG. 1 (a), the gap 5 between the overlapping portions of the water blocking member 3 is also clogged with earth and sand 5 having a permeability coefficient k, and the water head difference between the points a and c is Δh. Then, since the conditions are the same as in the case of FIG. 1 (b) except for the head difference H in the equation (1), the water permeability Q in the case of FIG._bQ_a= Q_b(Δh / h) Here, if Δh <h, Q_a<Q_bIt becomes.
[0018]
Next, the flow rate Q permeating through the water stop member 3_aIs the same flow rate between c and b between the overlapping water-stopping members due to the continuity of the fluid._a= K · δ · (h−Δh) / L. Therefore, the hydraulic head difference between a and c is Δh = h−Q_aL / (k · δ), and at least the water head difference is smaller than in Fig. 1 (b).
[0019]
That is, a substance that obstructs water permeability even slightly exists in the portion where the water blocking member 3 is overlapped, so that the water head at the point c falls, and as a result, the water head difference (hydrodynamic gradient) between a and c. ) Becomes smaller, it becomes possible to reduce the amount of water flow, and the water stoppage is improved.
[0020]
Moreover, in Claim 1, the joining method and joining position of the water stop member 3 to the steel sheet pile 1 are not particularly limited, and the gap amount and overlapping length of the overlapping portions of the pair of water stop members 3 and 3 are not particularly limited. There is no need for one joint portion located in the closed space formed by the water stop member 3 and the steel sheet pile 1, for example, one water stop member 3 or 3 is provided as shown in FIG. The steel sheet piles 1 </ b> A and 1 </ b> A may be joined to each other, and the two joint portions 2 may be positioned in the closed space 4. As a joining method of the water stop member 3, one that can be joined so that water does not permeate from the joined portion is preferable. The water stop member 3 may be provided in the steel sheet pile 1 in advance, or a joint member serving as a joint may be provided and the water stop member 3 may be driven. In addition, regarding the gap amount and the overlap length, it is desirable to make the gap amount as small as possible and make the overlap length as long as possible in consideration of workability. When steel sheet piles are placed in the soil, it is considered that the earth and sand are clogged with the passage of time between the gaps of the water stopping member, and it is considered that the water stopping effect is enhanced by this clogging of the earth and sand. Also, the state of the gap is not particularly limited, and it may be sufficient to predict whether clogging or clogging of water can be prevented.
[0021]
Further, the shape of the water stop member 3 is not particularly limited. In FIG. 1, a water stop member having an L-shaped cross section is used, and by using a commercially available angle steel material that is relatively easily available, costs such as material costs and processing costs of the water stop member can be kept low, It is also easy to arrange so that the overlapping parts of the water stop members are parallel to each other. As shown in FIG. 2 (c), a linear water-stopping member may be used.
[0022]
As an advantage obtained by making the overlapping portions of the water-stopping members 3 parallel, as shown in FIG. 2 (a), the end portions of the water-stopping members 3 and 3 are completely connected in the standard fitting state of the joint portion 2. When the water stop member 3 is joined to the steel sheet pile 1 so as to be in contact with the steel sheet, there is a section where no gap is generated, so the water stop effect is very high. As shown in FIG. 2 (b), even when the water stop member 3 is joined to the steel sheet pile 1 in the above state and the fitting state of the steel sheet pile joint portion 2 deviates from the standard when the steel sheet pile 1 is placed. As the contact surface gap of the steel sheet pile joint portion 2 is narrowed, only the gap amount between the water stop members 3 and 3 is increased, and the gap amount is at most about the gap amount inside the joint portion when fitting the steel sheet pile. It can be suppressed.
[0023]
As another advantage, since the steel sheet pile 1 can be driven straight using the water stop member 3 as a guide, the steel sheet pile hardly rotates or twists. In addition, it is difficult to form an opening, and as a result, water-stopping is improved.
[0024]
In Claim 2 of this invention, in the water stop structure of the steel sheet pile joint part of Claim 1, as shown in FIG. 3, a pair of water stop members 3 and 3 center on the steel sheet pile joint part 2. In the case where the steel sheet pile 1 rotates around the steel sheet pile joint portion 2, the overlapping portions of the pair of water-stop members 3, 3 are always parallel to each other. It was made to become. In addition, what is necessary is just to form an arc part in the part which overlaps at least.
[0025]
By doing in this way, contact with the water stop members 3 and 3 can be prevented also against the comparatively big rotation of the steel sheet pile 1 centering on the joint part 2, and there exists a possibility of fall of driveability. Disappear. In addition, as shown by the dotted line in FIG. 3, even if the water stop members 3, 3 are rotated in the direction in which the overlapping range of the water stop members 3 is reduced during construction by overlapping them over the rotatable angle, There are always overlapping parts, and there is no fear of the opening.
[0026]
  ClaimIn the water stop structure of the steel sheet pile joint part of 1, the opening part accompanying rotation during construction of the steel sheet pile centering on the joint part of the steel sheet pile by limiting the positional relationship of the water stop member joined to the steel sheet pile Consider preventionIf you want toAs shown in FIG. 4, the center position of the steel sheet pile joint 2 is the origin O, and the origin O is at the free end of the water stop member 3B whose overlapping part is far from the origin among the pair of water stop members 3A and 3B. In the coordinate system in which the perpendicular drawn from the axis is the Y-axis (the water-stopping member side is the positive direction) and the axis orthogonal to this is the X-axis, the free end of the water-stopping member 3A whose overlapping portion is closer to the origin The tip end position A of (x1, y1), the position A ′ farthest from the origin of the water stop member 3A (x1 ′, y1 ′), and the free end of the water stop member 3B whose overlapping portion is far from the origin When the tip position B of (x2, y2) and y1 <y2 is assumed, x1 · x2 <0, (x1²+ Y1²) ≧ y2², (X1 '² + Y1 '² ) ≧ (x2²+ Y2²) Are provided on the steel sheet piles 1, 1 so as to satisfyTo make.
[0027]
If the water-stop members 3A and 3B are joined to the steel sheet piles 1 and 1, respectively, as shown in FIGS. Since the tip is in point contact with another water-stop member, the generation of an opening due to the rotation of the steel sheet pile centering on the steel sheet pile joint portion is prevented. In order to limit in this way, it is necessary to unambiguously determine the perpendicular that defines the Y-axis, and at least the portion of the water-stopping members 3A and 3B that overlap each other is not linear. Don't be.
[0028]
  thisCaseHowever, even if the steel sheet pile rotates in any direction, there is always an overlapping part, there is no concern that the water stoppage will be reduced due to the opening, and even if contacted, only point contact at the tip part Therefore, it is possible to satisfy both the required performance of workability and water-stopping performance without drastically lowering the placing property. In the unlikely event that there is a concern that the castability will be reduced due to contact with the rotation of the steel sheet pile, it is possible to cope with this by making the water-stopping member flexible.
[0029]
  Of the present inventionClaim 3Claims1 or 2In the water stop structure of the steel sheet pile joint part, the shape of the steel sheet pile and the mounting position of the water stop member are limited. As shown in FIG. 6 and FIG. It has joints 2, 2 'of different shapes that can be fitted to each other at the tips of a pair of arms 12, 12 protruding left and right from the main body, and the steel sheet piles are in the same posture (the direction of the steel sheet piles in the same direction). The steel sheet pile 11 is fitted and driven, and the water stop member 3 is provided on one surface of the pair of arm portions 12 and 12. In the example of FIGS. 6 and 7, the joint portions 2 and 2 ′ are shaped so that the upper surface of the joint portion 2 ′ and the outer surface of the arm portion 12 are flush with each other when fitted.
[0030]
When a U-shaped steel sheet pile 1 having a general shape shown in FIG. 5 is used, two types of steel sheet pile 1A in which the water stop member 3 is bonded to the outer surface and a steel sheet pile 1B bonded to the inner surface are required. The processing, stacking, transportation, and construction management are complicated, and in some cases, stacking may not be possible.
[0031]
On the other hand, for example, when the steel sheet pile 11 having the shape shown in FIG. 6 (a) is used, as shown in FIGS. 6 (b), (c) and FIG. 7, either one of the inner and outer surfaces of the arm portion 12 is used. Since the water stop member 3 can be joined to the surface, there is an advantage that management on processing, stacking, transportation, or construction becomes easy.
[0032]
In this case, various bonding patterns of the water stop member 3 are conceivable. For example, in the case of FIGS. 6B and 6C, one type of steel sheet pile 11 in which the water stop members 3A and 3B are respectively joined to the left and right arm portions 12 can be used. In the case of FIG. The steel sheet pile 11A in which only the water stop member 3A is joined to the left and right arm portions 12 and the steel sheet pile 11B in which only the water stop member 3B is joined to the left and right arm portions 12 can be used alternately. .
[0033]
In addition, as shown in Fig. 6 (b) and Fig. 7 above, when it is necessary to consider the landscape, or when a solid flat surface is required for attaching a support member such as a lining material, In addition, at the time of fitting, the surface where the water stop member 3 is not joined becomes flat by joining the water stop member 3 to the side that does not form the same plane for the joint portion, so that the correspondence is easy. .
[0034]
  Of the present inventionClaim 4Claims 1 and 2Or 3In the water stop structure of the steel sheet pile joint part, as shown in FIG. 8, a water stop seal material 20 is provided in a gap between overlapping portions of the pair of water stop members 3 and 3.
[0035]
  Of the present inventionClaim 5Are claims 1, 2, 3Or 4In the water stop structure of the steel sheet pile joint part, as shown in FIG. 8, the water stop sealing material 20 is provided in the steel sheet pile joint part.
[0036]
  Claims 4 and 5In the above, examples of the water-stop sealing material include water-stop rubber and water-swellable resin paint. By providing such a water-stop sealing material, further water-stop improvement can be exhibited.
[0037]
  Of the present inventionClaim 6Are claims 1, 2, 3, 4Or 5In the water stop structure of the steel sheet pile joint part, as shown in FIG. 8, the closed space is filled with a material 30 having water stop.
[0038]
Examples of the water-stopping material include mortar, concrete, urethane resin, and the like, but there are no particular limitations on this. By introducing such a material into the closed space after placing the steel sheet pile, further improvement in water stoppage can be exhibited.
[0039]
When putting material that has water-stopping properties, if steel and sand are clogged in the closed space after placing steel sheet piles, it can be added after removing it with a water jet, etc. In addition, a water-stopping material that penetrates into the earth and sand and exhibits water-stopping properties together with the earth and sand may be used.
[0040]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described based on the illustrated embodiment. FIG. 1 (a) is an example applied to a U-shaped steel sheet pile, and is a water stop made of an angle steel material arranged in parallel with the joint portion 2 on the inner surface or outer surface of the flange portion on the left and right sides of the U-shaped steel sheet pile. The base end portion of the member 3 is joined by welding or the like. A pair of water stop members 3 in a state in which adjacent steel sheet piles are fitted to each other by the joint portion 2 by attaching the base end portion of the water stop member 3 to the flange portion of the U-shaped steel sheet pile 1 at a right angle. 3 are parallel to each other. Furthermore, if the length of the base end part and the length of the free end part of the pair of water blocking members 3 and 3 are appropriately determined, the free end parts overlap each other by a length L with a gap δ therebetween.
[0041]
After the steel sheet pile 1 is placed, the earth and sand 5 and the like are clogged in the closed space 4 surrounded by the pair of water-stopping members 3 and 3 and the gap between the overlapping free ends, and compared with FIG. The water head difference is reduced and the water permeability is reduced, so that the water stoppage is improved. Furthermore, as shown in FIG. 2 (a), if the gap of the joint portion 2 is in the standard fitting state of δ, the overlapping free ends of the pair of water blocking members 3 and 3 are in complete contact with each other. The water stop effect is further improved. Even if it shifts to the state shown in FIG. 2 (b), the gap between the overlapping free ends becomes δ, and sufficient water-stopping is ensured.
[0042]
Further, when the steel sheet pile 1 is driven, the parallel free ends of the pair of water-stop members 3 and 3 serve as guide members, so that the steel sheet pile 1 can be driven straight. Rotation and twisting can be prevented, and the generation of openings due to rotation and twisting can be prevented, thereby improving water stoppage.
[0043]
Furthermore, as shown in FIG. 4, by restricting the positional relationship between the pair of water-stop members 3 and 3, the generation of an opening due to rotation during construction of the steel sheet pile centering on the joint portion 2 of the steel sheet pile 1 is prevented. can do. That is, the point A (x of the inner water stop member 3A₁, Y₁) And point A '(x₁', y₁'), Point B (x of the outer water stop member 3B₂, Y₂) But x₁・ X₂<0, (x₁ ²+ Y₁ ²) ≧ y₂ ², (X₁'²+ Y₁'²) ≧ (x₂ ²+ Y₂ ²If the shape and dimensions of the pair of water stop members 3A and 3B are appropriately determined so that the steel sheet pile 1 rotates about the joint portion 2, the outer surface of the water stop member 3A Since the point contact is made with the inner surface of the member 3B, the generation of an opening accompanying the rotation of the steel sheet pile 1 is prevented. In addition, as long as the free end part of the outer water-stopping member 3B is linear, the other part can prevent the opening from occurring in any shape as long as the above-described conditions are satisfied.
[0044]
Moreover, as shown in FIG. 5, the steel sheet pile 1 has the steel sheet pile 1A which joined the water stop member 3A of the inner side to the outer surface in the flange part of a steel sheet pile, and the inner surface in the flange part of a steel sheet pile. Two types of steel sheet piles 1B bonded to each other may be prepared, and these may be driven alternately.
[0045]
Next, FIG. 3 is an example in which the shape of the water stop member 3 is changed, and the pair of water stop members 3 and 3 are concentric arcs with a predetermined gap around the center point O of the steel sheet pile joint portion 2. Yes. The base end portion of the arc-shaped water-stop member 3 is smoothly bent and joined to the inner surface or outer surface of the flange portion of the steel sheet pile 1 and joined by welding or the like. Note that the entire water stop member 3 may be formed in an arc shape, or only an overlapping portion may be formed in an arc shape.
[0046]
In this case, as in the case of the angle steel material, the water stoppage is improved by the overlapping free ends. Moreover, even if the steel sheet pile 1 centering on the joint part 2 is relatively rotated, contact between the water-stop members 3 and 3 can be prevented, and the placing property does not deteriorate. Furthermore, even if it rotates in the direction in which the overlapping range of the water-stopping member 3 decreases during construction by overlapping over a rotatable angle, there is always a portion where the water-stopping members 3 and 3 overlap, There is no fear of occurrence.
[0047]
Next, in FIGS. 6 and 7, straight arm portions 12 parallel to the main body web portion are integrally projected on the left and right sides of the U-shaped steel sheet pile main body. This is an example using a steel sheet pile 11 provided with joint portions 2, 2 ′ having different shapes (asymmetrical shapes) that can be fitted to each other. Further, the joint portions 2 and 2 ′ have a shape such that the upper surface of the joint portion 2 ′ and the outer surface of the arm portion 12 form the same plane when fitted.
[0048]
When such a steel sheet pile 11 is used, as shown in FIGS. 6 (b), 6 (c) and FIG. 7, the water stop member 3 can be joined to one of the inner and outer surfaces of the arm portion 12. As a result, processing, stacking, transportation, and construction management are facilitated. In the case of FIGS. 6B and 6C, one type of steel sheet pile 11 in which the water stop members 3A and 3B are joined to the left and right arm portions 12, respectively, can be used. In the case of FIG. 7, the steel sheet pile 11A in which only the water stop member 3A is joined to the left and right arm portions 12 and the steel sheet pile 11B in which only the water stop member 3B is joined to the left and right arm portions 12 are alternately used. Can be used. Furthermore, in the case of FIG. 6 (b) and FIG. 7, since a flat surface without a water-stopping member is formed on the arm portion 12, when the landscape must be taken into consideration, or a support member such as an angling material is used. It is possible to easily cope with the installation.
[0049]
Next, FIG. 8 shows a means for further improving the water stop performance by the pair of water stop members 3 and 3 according to the present invention. The gap between the overlapping portions of the pair of water stop members 3 and 3 and the pair of joint portions. 2 and 2, a water-stop sealing material 20 such as a water-stop rubber or a water-expandable resin paint is provided. In addition, a material 30 having a water-stopping property such as mortar, concrete, and urethane resin is placed in the closed space 4 after being placed. In this case, after placing the steel sheet pile, the earth and sand clogged in the closed space 4 are removed after being removed by a water jet or the like. In the case of a water-stopping material that penetrates into the earth and sand and exhibits water-stop together with the earth and sand, the earth and sand may not be removed.
[0050]
In addition, it cannot be overemphasized that this invention is applicable to the steel sheet pile of another shape, without being limited to the steel sheet pile of the shape shown in figure.
[0051]
【The invention's effect】
Since this invention consists of the above structures, there can exist the following effects.
(1) Since the free ends of a pair of water-stopping members are overlapped, the amount of water permeation can be reduced by the overlapped portions, and a gap is also generated when the steel sheet pile rotates or twists Therefore, the water stoppage can be significantly improved by the waterstop member having a relatively simple structure.
(2) Furthermore, since it is assumed that the overlapped part of the pair of water-stopping members creates a gap, it does not hinder the driving performance of the steel sheet pile and satisfies both the driving performance and water-stopping performance at the same time. Can be made.
(3) By limiting the positional relationship between the pair of water-stopping members, or by making the pair of water-stopping members concentric arcs, even if the steel sheet pile rotates around the joint during placement, There is no fear of occurrence, and sufficient water stopping performance can be obtained with certainty.
(4) The water stop by the pair of water stop members by providing a water stop seal material in the gap between the overlapping portions of the pair of water stop members and the pair of joints, or by filling the closed space with a material having a water stop property. The performance can be further improved.
(5) A steel sheet pile that has joints of different shapes that can be fitted to each other at the ends of a pair of arms protruding left and right from the steel sheet pile body, and each steel sheet pile is fitted and driven in the same posture. By using a sheet pile, a pair of water-stopping members can be provided on any one surface of the pair of arms, and management on processing, stacking, transportation, construction, etc. is facilitated.
[Brief description of the drawings]
FIG. 1 is a plan view showing an example of a water stop structure of a steel sheet pile joint according to the present invention, where (a) is an example of the present invention and (b) is a comparative example.
FIGS. 2A and 2B are plan views showing a state after a steel sheet pile of a water-stopping structure of a steel sheet pile joint according to the present invention, wherein FIG. 2A shows a standard fitting state and FIG. 2B shows a state deviating from the standard. . (c) is a top view which shows the other example of the water stop structure of FIG.
FIG. 3 is a plan view showing an example in which the shape of the water stop member of the water stop structure of the steel sheet pile joint portion of the present invention is different.
4 is a plan view for explaining prevention of opening in the water blocking member of FIG. 1. FIG.
5 is a plan view showing an arrangement state of the steel sheet piles of FIG. 1. FIG.
FIG. 6 is a plan view showing another example of steel sheet piles applied to the water stop structure of the present invention and its arrangement.
7 is a plan view showing a case where the method of attaching the water stop member of the steel sheet pile of FIG. 6 is different.
FIG. 8 is a plan view showing means for further improving the water stop performance in the water stop structure of the present invention.
FIG. 9 is a plan view showing a conventional steel sheet pile for water stop (No. 1).
FIG. 10 is a plan view showing a conventional steel sheet pile for water stop (No. 2).
FIG. 11 is a plan view showing a conventional steel sheet pile for water stop (No. 3).
[Explanation of symbols]
1 ... Steel sheet pile
2 ... Fitting part
3 ... Water stop member
4 ... Closed space
5 ... earth and sand
11 ... Steel sheet pile
12 ... arm
20 ... Water seal material
30 ... Material having water-stopping property

Claims

The steel sheet pile is provided with a water stop member so that a closed space that covers the steel sheet pile joint portion is formed by a pair of water stop members that partially overlap when the joint portions of the steel sheet piles are fitted together. A water stop structure for a steel sheet pile joint.

The water stop structure for a steel sheet pile joint portion according to claim 1, wherein the pair of water stop members have a shape in which a part thereof overlaps in a concentric arc shape centering on the steel sheet pile joint portion.

Steel sheet piles are steel sheet piles that have joints with different shapes that can be fitted to each other at the ends of a pair of arms protruding left and right from the steel sheet pile body, and each steel sheet pile is fitted and driven in the same posture. , water stop structure of the steel sheet pile joint according to claim 1 or 2, characterized in that water-shutoff member either to one surface of the pair of arm portions are provided.

The water stop structure of the steel sheet pile joint part according to claim 1, 2 or 3 , wherein a water stop seal material is provided in a gap between overlapping portions of the pair of water stop members.

The water stop structure of the steel sheet pile joint part according to claim 1, 2, 3, or 4 , wherein a water stop seal material is provided in the steel sheet pile joint part.

The water-stopping structure for steel sheet pile joints according to claim 1, 2, 3, 4, or 5 , wherein the closed space is filled with a material having water-stopping properties.