JP2004251091A

JP2004251091A - Steel sheet-pile and sheet pile type steel wall

Info

Publication number: JP2004251091A
Application number: JP2003106932A
Authority: JP
Inventors: Yutaka Kano; 裕鹿野
Original assignee: Sumitomo Metal Industries Ltd
Current assignee: Nippon Steel Corp
Priority date: 2002-12-27
Filing date: 2003-04-10
Publication date: 2004-09-09
Anticipated expiration: 2023-04-10
Also published as: JP3659249B2

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sheet pile type steel wall at a comparatively low cost, which is maintained easily for a prolonged term and has excellent driving properties and water-barrier properties by making the most of the shape and features of a steel sheet-pile with an asymmetric joint, and also to provide the steel sheet-pile suitable for this application. <P>SOLUTION: The steel sheet-piles 1, in which the shapes of the joints 2 and 3 at both ends are formed in a left-right asymmetric shape and one joint 2 is formed inwards to the outermost edge of the sheet-pile wall and the other joint 3 outwards, are combined linearly while cross sectional shapes are arranged in the same direction. Inward projections 2a for constraining a rotation in joint sections are formed at base sections on the inward joint 2 sides, and inward projected upstanding sections 3a are formed at base sections on the outward joint 3 sides. A part or the whole of the projection 2a is composed of a material 5a having the melting point lower than other sections, and high water barrier properties are imparted to the steel wall A by continuously joining outer side faces 3b on the outward joint 3 sides and the projections 2a in the longitudinal direction under the state in which the joints 2 and 3 are engaged and a plurality of the steel sheet-piles 1 are connected. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本願発明は、廃棄物処理場の有害浸出水を防止するための外周護岸や中仕切り護岸、堤防の遮水壁など高い遮水性が要求される矢板式鋼製壁およびその用途に好適な鋼矢板に関するものである。
【０００２】
【従来の技術】
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に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、比較的遮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、嵌合状態において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遮水性に大きく影響する。
【０００４】
一般的には、打設直後の継手部は比較的水を通しやすい状態であったとしても、時間の経過に伴い、水の流れとともに継手内部に土粒子等が詰まってくるため、遮水性が向上して行くものであるが、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、より遮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。
【０００５】
しかしながら、この隙間が小さすぎると、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、遮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遮水性を高めるかが大きな課題の一つであった。
【０００６】
このような課題を解決するための従来技術の一例としては、継手内部の隙間を埋めるべく、あらかじめ鋼矢板の継手部に遮水用樹脂塗料を塗布するものが挙げられる。これは、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の遮水性の向上を期待したものである。
【０００７】
例えば特許文献１に開示されている技術は、鋼矢板打設前に水膨張性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、継手内部が樹脂で満たされることによって遮水性を高めるものである。
【０００８】
しかしながら、特許文献１記載の技術には、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、不可避的要素により遮水性が低下するという問題がある。
【０００９】
塗膜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。さらに、上記樹脂塗料の性能の経年劣化すなわち耐久性に関しても信頼性の点で問題があるのが現状である。
【００１０】
また、鋼矢板打設後、継手内部の隙間にグラウトを注入することで隙間を埋める技術がある。例えば特許文献２に記載されたものがあり、嵌合される２つの矢板の各継手部分の一方または両方に部材を設け、この部材により矢板間にグラウト注入空間を形成している。
【００１１】
特許文献２記載の鋼矢板では、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、遮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、遮水性が高い一方で継手部の余裕がないことに起因して施工性が悪い。
【００１２】
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箇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不可能である。さらには、遮水処理後のグラウト材の経年に伴う収縮や、矢板壁への外力の作用による鋼矢板の変形に起因するグラウト材の矢板壁からの剥離の問題も看過できない。
【００１３】
また、最近では特許文献３に開示されているように、継手部を有する鋼矢板において、互いに嵌合する継手部３１，３１の少なくとも一方の継手部の、第１または第２の嵌合内接面に、他方の継手部の第１または第２嵌合内接面と接する間隔保持用突起状体３７と吸水膨潤性遮水材３８を設けたもの（図１２参照）や、特許文献４に開示されているように、鋼板を冷間圧延成形した鋼矢板状の型鋼に、別途製作した継手部材４３を取り付けたものがある（図１３参照）。
【００１４】
ところで、本出願人は既に、特許文献５に記載されているように、鋼矢板５１の継手部５２，５３どうしを嵌合させた際に、一部が重なり合う一対の遮水部材５４，５５により鋼矢板継手部５２，５３を覆う閉合空間が形成されるように、鋼矢板５１のフランジ部分の内面あるいは外面に遮水部材５４，５５の基端部を溶接等で接合し、遮水部材５４，５５の重ね合せ部分で透水量を低減し、鋼矢板５１が回転したり捩じれたりした場合にも継手部５２，５３における隙間の発生をなくして遮水性を大幅に向上させ、また重ね合せ部分の隙間により打設性も損なわれない鋼矢板継手部の遮水構造を提案している（図１４参照）。
【００１５】
さらに、本出願人は、特許文献６に記載されているように、鋼矢板６１どうしの継手部６２，６３近傍の平面部分に、膨張性を有する遮水材６４を設置し、これを覆うように鋼板などからなる拘束部材６５を取り付ける鋼矢板継手部の遮水構造およびその施工方法を提案している（図１５参照）。
【００１６】
特許文献６記載の発明では、遮水材６４は拘束部材６５と鋼矢板６１に挟まれた状態で、遮水材６４自身が持つ膨張力により膨張しようとするため、拘束部材６５から押圧力を受け、継手部における遮水性を確保する。また、鋼矢板６１として、継手部６２，６３の嵌合状態において遮水材６４を設置した側が同一平面をなす形状の鋼矢板６１を用いることで、遮水構造を単純化し、打設性も確保した上で遮水性を高めることができる。
【００１７】
【特許文献１】
特開平１−１６８７６６号公報
【特許文献２】
特開平１−２８０１２２号公報
【特許文献３】
特開２０００−１９２４５１号公報
【特許文献４】
特開２０００−０７３３６１号公報
【特許文献５】
特開２００１−２１４４３５号公報
【特許文献６】
特開２００２−１４６７７２号公報
【００１８】
【発明が解決しようとする課題】
従来の技術の項で述べた各発明に共通する問題として、鋼矢板とは別に間隔保持用突起状体、特殊形状の継手部材、遮水部材あるいは拘束部材の製作および取付けの必要があるほか、遮水性を高めるための遮水シール材や膨張性を有する遮水材、あるいはグラウト材などが必要であり、遮水を実現するためのコスト（遮水部材、遮水材等の製造コストや現場施工コスト）が高くつくといったことが挙げられる。
【００１９】
さらに、既述した通り、遮水シール材、膨潤性を有する遮水材あるいはグラウト材等を用いる場合には、その経年劣化や矢板壁に外力が作用した際の剥離に起因する遮水性能の低下という問題がある。
【００２０】
本願発明は、上述のような従来技術における課題の解決を図ったものであり、本出願人が開発した非対称継手を有する鋼矢板の形状・特徴を生かすことで要求される打設性および遮水性の両者を満足し、比較的安価な製造および施工コストで実現可能であって、さらには、遮水処理後の鋼矢板変形に対しても遮水性能が確保でき、長期に亘り遮水性能を維持するための維持管理が容易な、遮水性に優れた矢板式鋼製壁およびその用途に用いるのが好適な鋼矢板を提供することを目的としている。
【００２１】
【課題を解決するための手段】
本願の請求項１に係る鋼矢板は、両端の継手部における継手形状が左右非対称で、前記両端の継手部の近傍に打設法線と同方向となるフラット部と、フラット部に対して一方が内向き、他方が外向きに形成された前記継手部と、前記継手の少なくとも一方の継手の基部に突起を有し、横断面形状を同一方向にそろえて直線状に結合可能な鋼矢板であって、前記突起の一部若しくは全部が矢板壁の他の部分に比べて低融点の材料から構成されていることを特徴とするものである。
【００２２】
鋼矢板の全体形状としては、直線型、Ｕ型（ウエブとその両側にフランジを有する形状等）のいずれであっても良い。
【００２３】
突起の一部若しくは全部を構成する低融点材料としては、鋼材よりも低融点の溶接材料（溶加材）やろう付けろう（真鍮ろうや銀ろう）が好適である。
【００２４】
突起の基部に設けられた突起によって、鋼矢板は継手部における回転を拘束される。
【００２５】
本願の請求項２に係る鋼矢板は、両端の継手部における継手形状が左右非対称で、前記両端の継手部の近傍に打設法線と同方向となるフラット部と、フラット部に対して一方が内向き、他方が外向きに形成された前記継手部と、前記内向きの継手側の基部に内向きの突起と、前記外向きの継手側の基部に内向きの立上り部とを有し、横断面形状を同一方向にそろえて直線状に結合可能な鋼矢板であって、前記突起の一部若しくは全部が矢板壁の他の部分に比べて低融点の材料から構成されていることを特徴とするものである。
【００２６】
すなわち、請求項２に係る発明は、請求項１に係る鋼矢板において、一方の継手である内向きの継手側の基部に内向きの突起を有し、他方の継手である外向きの継手側の基部に内向きの立上り部を有する場合に相当する。
【００２７】
本願の請求項３に係る矢板式鋼製壁は、請求項１または２に係る鋼矢板どうしが、前記継手部で連結され、前記継手部の外側面と前記突起とが長手方向に連続して隙間なく接合された接合部を有することを特徴とするものである。
【００２８】
上記接合部の形成する際の前記突起を加熱する手段としては、ガスシールドアーク溶接であれば、ＴＩＧ、プラズマアーク等の非消耗電極型が好適であり、シールドガスの種類は問わない。例えば、水中での接合であれば、プラズマアーク溶接のアークを用いて接合部位を加熱する方法が適しており、気中で接合するのであれば、ガスバーナーでの加熱により、溶加材やろうを溶融させる方法でも良い。
【００２９】
請求項４に係る発明は、請求項２に係る矢板式鋼製壁において、前記矢板式鋼製壁の前記接合部を有する側が向き合う状態で、前記矢板式鋼製壁どうしが水中および／または地中に設けられていることを特徴とするものである。
【００３０】
本出願人は、既述の従来技術の課題を解決するために、図２に示すような非対称な継手２，３（図２（ａ）は複数の鋼矢板１を継手部で連結した状態を示す平面図、図２（ｂ）は継手嵌合部の拡大図）を有する鋼矢板１の継手形状の特徴を生かし、図１に示すような継手嵌合部の接合を発案した。
【００３１】
すなわち、本出願人は、図２に示す左右非対称な継手２，３の嵌合部において、外向き継手３の外側面３ｂと内向きの突起２ａを鋼矢板１の長手方向に連続して隙間なく接合することを目的として、内向きの突起２ａのほぼ全体を鋼矢板１の他の部分に比べて低融点の材料５ａとした場合（図１（ｂ））と、内向きの突起２ａを鋼矢板１の他の部分と同一材料とした場合（図５（ａ））の両者を比較して以下の知見を得た。
【００３２】
なお、この際、加熱手段としては非消耗電極型のガスシールドアーク溶接の１つであるプラズマアーク溶接装置を用いて、大気中で内向きの突起２ａに狙いを定めて加熱する方法を採用した。
【００３３】
前者（図１）においては母材が溶融を開始する前に接合材料（低融点材料５ａ）が溶け出し、外向き継手３の外側面３ｂと内向きの突起２ａとの間に比較的容易に接合材料が隙間なく、遮水性を有するように形成される。
【００３４】
一方、後者（図５）においては内向きの突起２ａと母材とは同一の材料（鋼材）であり、突起の融点が高いので、加熱用のアークの向きや突起２ａとの距離によって該突起２ａの溶融状況が変化し、図５（ｂ）に模式的に示すように、接合部長手方向の位置によっては接合不良部位が発生する（外向き継手３の外側面３ｂと内向きの突起２ａとの間に水が侵入する程度の隙間が空く）。
【００３５】
あるいは、アークの向き、突起２ａとの距離や入熱量によっては、図示しないが内向き突起２ａの根元部分や外向き継手３部分を削ぎ落としてしまうトラブルが発生することがあった。
【００３６】
そのため、鋼矢板１の長手方向に連続して接合する場合には、アークの位置・角度を正確に保持し、入熱量を適切に調整する必要があるほか、接合速度を前者（図１）に比べてかなり低下させないと、上記接合時のトラブルを回避し、外向き継手３の外側面３ｂと内向きの突起２ａを遮水性を有するように隙間なく接合することは極めて困難となることがわかった。
【００３７】
以上、大気中における継手接合実験の結果に基づいて説明したが、気中に比べて水中では、溶融した部材が周囲の水によって抜熱され固化しやすいので、接合材料となる突起を溶融させるためには、加熱用アークによる入熱量を大きくしなければならない。
【００３８】
突起の一部または全部に低融点材料を用いずに水中で継手を接合する場合には、既述のように鋼矢板のフランジに孔があいたり、継手部分を削ぎ落としてしまうというトラブルがより発生しやすく、本願発明に係る鋼矢板は水中で接合する場合に好適である。
【００３９】
【発明の実施の形態】
図１は、請求項１、請求項２に係る発明の一実施形態を示したもので、非対称継手２，３を有するＵ型鋼矢板１を１列に連結した後、継手嵌合部を溶接し、鋼製壁Ａを形成している。
【００４０】
この例では、鋼矢板１の内向きの継手２側の基部に内向きの突起２ａが形成され、外向きの継手３側の基部に内向きに突出する立上り部３ａが形成されている。
【００４１】
内向きの突起２ａの一部若しくは全部が他の部分に比し低融点の材料５ａから構成されており、内向きの継手２と外向きの継手３を係合させて複数の鋼矢板１を連結し、外向きの継手３側の外側面３ｂと内向きの継手２側の突起２ａとの間を長手方向に連続して隙間なく溶接することで、鋼製壁Ａに高い遮水性を与えている。
【００４２】
鋼製壁Ａの施工方法としては、水中および／または地中に鋼矢板１を１枚ずつ継手２，３を嵌合させながら施工した後、該継手２，３を接合する方法でも良いし、複数の鋼矢板１を予め継手部で連結並びに接合して一体化したものを複数枚用意し、継手２，３を嵌合させながら水中および／または地中に施工した後、該継手２，３を接合する方法でも良い。
【００４３】
図３は、他の実施形態として、内向きの突起２ａの一部のみを低融点材料５ａとした場合の外向きの継手３の外側面３ｂと内向きの突起２ａの接合前後の状態を示している。
【００４４】
図３の実施形態では、内向きの突起２ａについて、外向きの継手３に対峙する側のみを低融点材料５ａとしているが、例えば内向きの突起２ａの上部の何分の一かを低融点材料５ａとすることも可能である。
【００４５】
なお、図３（ａ）に示すように低融点材料５ａを内向きの突起２ａと一体化させる方法としては、接着剤による方法や、鋼矢板１の熱間圧延終了後の適当な母材温度にあるときに、低融点材料５ａを所定の位置に所定の形状に流し込み、その後冷却して硬化させる方法等がある。
【００４６】
図４は、内向きの突起２ａの一部を低融点材料５ａに置換える他の方法を示したもので、低融点材料５ａ（熱溶融材料）を予め内向きの突起２ａの一部または全部の形状に成形したものを用意しておき、母材である鋼矢板の方も上記内向きの突起２ａが例えば印籠構造で嵌合できるように成形しておき、両者を嵌合一体化させる場合である。嵌合面には予め接着剤を塗布しておいたり、あるいは両者を嵌合を嵌合した後、ネジ（図示せず）等で留めても良い。
【００４７】
図６は、本願の請求項１に係る発明の他の実施形態を示したもので、図１の実施形態の場合と同様、非対称継手２，３を有するＵ型鋼矢板１を１列に連結した後、継手嵌合部を溶接し、鋼製壁Ａを形成している。
【００４８】
図１の実施形態との違いとして、図６の実施形態では、外向きの継手３側にも立上り部３ａとの間に、外向きの突起３ｃが形成されており、このような継手２，３を係合させた状態で、外向きの継手３側の外側面３ｂと内向きの継手２側の突起２ａとの間を長手方向に連続して隙間なく溶接している。
【００４９】
この場合の溶接箇所としては、図示の箇所以外に、外向きの突起３ｃと内向きの突起２の外側面２ｂとの間であってもよく、その場合、外向きの突起３ｃの一部若しくは全部が他の部分に比し低融点の材料５ａから構成される。
【００５０】
また、図６の実施形態に対しても、図１の実施形態に対する図３、図４と同様の変形形態、すなわち外向きの突起３ｃについて、内向きの継手３に対峙する側のみを低融点材料とするか、あるいは外向きの突起３ｃの図中下部の何分の一かを低融点材料とすることや、低融点材料を予め外向きの突起３ｃの一部または全部の形状に成形したものを用意しておき、母材である鋼矢板の方も上記外向きの突起３ｃが例えば印籠構造で嵌合できるように成形しておき、両者を嵌合一体化させるといった変形形態が考えられる。
【００５１】
また、図１、図６の実施形態の何れの場合も、突起２ａまたは突起３ｃは継手部における回転を拘束することができ、かつ継手２，３どうしが容易に離脱しないものであればよく、例えば図示したものより低いものでもよい。
【００５２】
さらに、継手２，３に対するフラット部４の位置は、図示したような内向きの継手２の最下端および外向きの継手３の最上端だけでなく、継手２，３の嵌合に支障をきたさない位置であれば、特に限定されない。
【００５３】
図７（ａ）、（ｂ）は、請求項４に係る発明の一実施形態を示したもので、これらは非対称継手２，３を有するＵ型鋼矢板１を２列に連結した後、鋼矢板１どうしを矢板壁の最外縁に対して互いに内向き方向に対峙させた状態で、各継手嵌合部を接合し、鋼製壁Ａを形成している。図７（ａ）が２列の矢板壁が近接しているのに対し、図７（ｂ）は２列の矢板壁が離間している場合である。
【００５４】
鋼製壁の施工方法としては、各列を別々に水中および／または地中に設けるのが一般的であるが、可能であれば２列の鋼矢板壁を互いに離間した状態で同時に施工しても良い。
【００５５】
この場合の特徴としては、２列に水中および／または地中に設けられた向かい合う鋼矢板壁に外界と隔離された閉空間が形成されるため、地中に設けられた部分を掘削し、継手嵌合部およびその周辺部の土砂を排除することで、その後の継手嵌合部の接合施工が容易となる点が挙げられる。
【００５６】
また、遮水処理後は、上記閉空間は外界とは遮断されるため、継手接合部の監視や補修といった用途にも活用できる。
【００５７】
図８（ａ）、（ｂ）は、請求項４に係る発明の他の実施形態を示したもので、これらは非対称継手２，３を有する２枚のＵ型鋼矢板１どうしをそれぞれの矢板壁の最外縁に対して互いに内向き方向に対峙させた状態で、直接溶接あるいは鋼板やＨ形鋼等の鋼材を介して溶接し一体化したものを１列に連結した後、継手嵌合部を接合して遮水性に優れた鋼製壁Ａを形成している。図８（ａ）は２枚のＵ型鋼矢板１どうしを直接溶接一体化した場合、図８（ｂ）はＨ形鋼７を介して溶接一体化してある場合である。
【００５８】
この場合の特徴としては、鋼矢板１の水中および／または地中への施工が２枚同時に行えるため、施工（打設）能率が向上する他、水中および／または地中設置後の鋼矢板１どうしの間隔を一定に保持できるため、図１０に示すような移動接合機の導入に適し、継手嵌合部の接合施工の効率化が図れる。
【００５９】
また、図７の実施形態の場合と同様に、外界と隔離された閉空間が形成されるため、地中に施工された部分を掘削し、継手嵌合部およびその周辺部の土砂を排除することで、その後の継手嵌合部の接合施工が容易となる。
【００６０】
また、遮水処理後は、上記閉空間は外界とは遮断されるため、継手接合部の監視や補修といった用途に活用できる。
【００６１】
図９は、請求項４に係る発明のさらに他の実施形態を示したもので、非対称継手を有する２枚の直線型鋼矢板１１どうしをそれぞれの矢板壁の最外縁に対して互いに内向き方向に対峙する形で、鋼板１２を介して溶接し一体化したものを１列に連結した後、継手嵌合部を接合し、鋼製壁Ａを形成している。
【００６２】
この場合も、図８の実施形態と同様、鋼矢板の水中および／または地中への施工が２枚同時に行えるため、施工（打設）能率が向上する他、水中および／または地中設置後の鋼矢板１１どうしの間隔を一定に保持できるため、図１０に示すような移動接合機の導入に適し、継手嵌合部の接合施工の効率化が図れる。
【００６３】
また、外界と隔離された閉空間が形成されるため、地中に設けられた部分を掘削し、継手嵌合部およびその周辺部の土砂を排除することで、その後の継手嵌合部の接合施工が容易となる。
【００６４】
また、遮水処理後は、上記閉空間は外界とは遮断されるため、継手接合部の監視や補修といった用途に活用できる。
【００６５】
なお、以上の実施形態における接合方法としては、図１０や図１１に示すような、鋼矢板の長手方向に連続して所定の接合速度で所定位置の接合が可能な移動式の接合機８，９、望ましくは自動溶接ロボットを用いることが施工能率の面から有効であるが、手動介入による接合でも良い。
【００６６】
また、図１０や図１１に例示した移動式接合機を用いた継手嵌合部の接合においては、嵌合部に入り込んだ土砂等の異物を排除するため、水あるいはエア等のガスによる接合位置のパージを接合直前に行う機能を付与することが望ましい。
【００６７】
【発明の効果】
本願発明の鋼矢板および矢板式鋼製壁は、以上説明したように構成され、連結、施工された鋼矢板の継手部は接合時のトラブルがなく、隙間なく安定して接合されるので、鋼矢板どうしの継手部分から地下水や海水が侵入するのを完全に防止することができる。
【００６８】
さらに、膨潤性遮水材や遮水部材等が不要なため、製作コストおよび施工コストが安価で、鋼矢板とＨ形鋼等の他の鋼材と組合わせることで、様々な断面性能を有する鋼製壁が実現できる。
【００６９】
また、請求項４に係る発明では、接合した継手部のモニタリング空間を確保することで、施工完了後の接合部の維持点検や補修が容易になり、遮水性能が長期にわたり維持できる。
【００７０】
さらに、複数列の鋼矢板を連結・施工した場合には、継手部の接合が２列同時に可能となるため、施工時間が短縮でき、施工コストが安価になる等の効果を有する。
【図面の簡単な説明】
【図１】本願の請求項１、請求項２に係る鋼矢板および矢板式鋼製壁の一実施形態を示したもので、（ａ）は非対称継手を有する鋼矢板を連結した状態を示す平面図、（ｂ）、（ｃ）は接合の様子を示す要部拡大図である。
【図２】（ａ）は本願発明の対象となる非対称継手を有する複数の鋼矢板を継手部で連結した状態を示す平面図、（ｂ）はその継手嵌合部の拡大図である。
【図３】（ａ）、（ｂ）は本願発明の鋼矢板および矢板式鋼製壁の他の実施形態における接合の様子を示す要部の平面図である。
【図４】（ａ）、（ｂ）は内向きの突起の一部を低融点材料に置き換える方法の一例を示す説明図である。
【図５】（ａ）、（ｂ）は比較例としての不具合な接合状況の説明図である。
【図６】本願の請求項１に係る鋼矢板および矢板式鋼製壁の他の実施形態を示したもので、（ａ）は非対称継手を有する鋼矢板を連結した状態を示す平面図、（ｂ）、（ｃ）は接合の様子を示す要部拡大図である。
【図７】請求項４に係る発明の一実施形態を示す平面図であり、（ａ）が２列の矢板壁が近接している場合、（ｂ）は２列の矢板壁が離間している場合である。
【図８】請求項４に係る発明の他の実施形態を示す平面図であり、（ａ）は２枚のＵ型鋼矢板どうしを直接溶接一体化した場合、（ｂ）はＨ形鋼を介して溶接一体化してある場合である。
【図９】請求項４に係る発明のさらに他の実施形態を示す平面図である。
【図１０】移動式接合機を用いた継手嵌合部の接合方法の一例を示す平面図である。
【図１１】移動式接合機を用いた継手嵌合部の接合方法の他の例を示す平面図である。
【図１２】従来例としての特許文献３における遮水構造を示す平面図である。
【図１３】従来例としての特許文献４における遮水構造を示す平面図である。
【図１４】従来例としての特許文献５における遮水構造を示す平面図である。
【図１５】従来例としての特許文献６における遮水構造を示す平面図である。
【符号の説明】
Ａ…鋼製壁、
１…鋼矢板、２…内向き継手、２ａ…内向きの突起、２ｂ…外側面、３…外向き継手、３ａ…立上り部、３ｂ…外側面、３ｃ…外向きの突起、４…フラット部、５ａ…低融点材料、５ｂ…溶接、６…溶接、７…Ｈ形鋼、８…移動式接合機、８ａ…溶接トーチ、８ｂ…走行用レール、８ｃ…走行用ローラー、９…移動式接合機、９ａ…溶接トーチ、９ｂ…接合機間間隔調整用パンタグラフ、９Ｃ…位置決め兼走行用ローラー、１１…直線型鋼矢板、１２…鋼板[0001]
TECHNICAL FIELD OF THE INVENTION
The invention of the present application is a sheet pile type steel wall which requires high water shielding such as an outer seawall or a partition seawall to prevent harmful leachate of a waste disposal plant, a water barrier of a dike, and a steel sheet pile suitable for the use thereof. It is about.
[0002]
[Prior art]
Steel sheet piles are often used for retaining walls in the construction of underground structures and temporary deadlines in 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 relatively excellent water shielding properties.
[0003]
Naturally, the steel material of the steel sheet pile main body is completely impervious to water. However, in the fitted state, the gap existing in the joint part allows water to pass, so that the gap in the joint part greatly affects the water shielding of the steel sheet pile.
[0004]
In general, even if the joint immediately after casting is relatively easy to penetrate water, soil particles and the like are clogged inside the joint with the flow of water over time, so that Although it will be improved, if the clogging inside the joint due to soil particles etc. can not be expected, or in order to further improve the water shielding, it is considered as a proposal to make the gap inside the joint as small as possible. Can be
[0005]
However, if this gap is too small, there is a problem that the casting resistance at the joint portion becomes extremely large, and water shielding and workability have conflicting required performances. It was not possible to make it smaller or larger, and one of the major issues was how to increase the water shielding of the joint.
[0006]
As an example of a conventional technique for solving such a problem, there is a technique in which a water-blocking resin paint is applied to a joint portion of a steel sheet pile in advance in order to fill a gap inside the joint. This is expected to improve the water barrier by blocking the water permeation path inside the joint with a resin paint having a relatively small water permeability.
[0007]
For example, in the technique disclosed in Patent Document 1, a water-swellable paint is applied to a gap in a joint portion before driving a steel sheet pile, and after driving, the resin that has absorbed surrounding moisture expands, and the inside of the joint is formed of resin. It is intended to increase the water barrier by being filled.
[0008]
However, in the technique described in Patent Document 1, the water barrier is reduced due to unavoidable factors such as uneven application when applying the resin paint to the joint portion before casting and damage to the coating film of the resin paint during casting. There's a problem.
[0009]
When a defective portion is generated in the coating film, even if the defective portion is relatively small, the flow velocity of water at the defective portion is relatively high, and there is a possibility that the defective portion may be enlarged by the flow. Furthermore, there is a problem in terms of reliability with respect to aging deterioration of the performance of the resin coating, that is, durability.
[0010]
Also, there is a technique for filling a gap by injecting grout into a gap inside the joint after driving a steel sheet pile. For example, there is one described in Patent Literature 2, in which a member is provided at one or both of joint portions of two fitted sheet piles, and a grout injection space is formed between the sheet piles by this member.
[0011]
In the steel sheet pile described in Patent Literature 2, the grout injection space is formed by the fitting of the joints, and the space is completely closed by the joints. Therefore, it is considered that the water shielding is high, but the joint shape is very complicated. Therefore, there is a disadvantage that the manufacturing cost is increased. In addition, workability is poor due to lack of room for joints while having high water shielding.
[0012]
Furthermore, in this joint shape, when the construction extension is curved, etc., it is impossible to construct each steel sheet pile in a curved shape while forming an angle at the joint portion for fitting at two places. is there. Furthermore, the problem of shrinkage of the grout material after the water impermeability treatment with the passage of time and the problem of peeling of the grout material from the sheet pile wall due to deformation of the steel sheet pile due to the action of an external force on the sheet pile wall cannot be overlooked.
[0013]
Further, as disclosed in Patent Document 3, recently, in a steel sheet pile having a joint portion, at least one joint portion of at least one of the joint portions 31 to be fitted to each other has a first or second internal fitting. The surface provided with a space-maintaining projection 37 and a water-absorbing and swellable water-blocking material 38 which are in contact with the first or second fitting inner contact surface of the other joint portion (see FIG. 12). As disclosed, there is one in which a joint member 43 separately manufactured is attached to a steel sheet pile-shaped steel sheet obtained by cold rolling a steel sheet (see FIG. 13).
[0014]
By the way, as described in Patent Document 5, the present applicant has already provided a pair of water-impervious members 54, 55 that partially overlap each other when fitting portions 52, 53 of steel sheet pile 51 are fitted together. The base ends of the water shielding members 54 and 55 are joined to the inner surface or the outer surface of the flange portion of the steel sheet pile 51 by welding or the like so that a closed space that covers the steel sheet pile joints 52 and 53 is formed. , 55, the water permeability is reduced, and even when the steel sheet pile 51 is rotated or twisted, gaps are not generated in the joints 52, 53, so that the water shielding is greatly improved. (See FIG. 14).
[0015]
Furthermore, as described in Patent Document 6, the present applicant installs a water-blocking material 64 having expandability on a flat portion near the joints 62 and 63 of the steel sheet piles 61 and covers the same. Proposed a water-tight structure of a steel sheet pile joint portion to which a restraining member 65 made of a steel plate or the like is attached (see FIG. 15).
[0016]
In the invention described in Patent Literature 6, the water blocking material 64 tends to expand due to the expansion force of the water blocking material 64 itself in a state of being sandwiched between the restraining member 65 and the steel sheet pile 61. To secure the water-shielding at the joints and joints. In addition, by using the steel sheet pile 61 having a shape in which the side on which the water shielding material 64 is installed is in the same plane when the joint portions 62 and 63 are fitted together, the water shielding structure is simplified and the casting performance is improved. It is possible to increase the water shielding property after securing.
[0017]
[Patent Document 1]
Japanese Patent Application Laid-Open No. 1-168766 [Patent Document 2]
JP-A-1-280122 [Patent Document 3]
JP 2000-192451 A [Patent Document 4]
JP 2000-073361 A [Patent Document 5]
JP 2001-214435 A [Patent Document 6]
Japanese Patent Application Laid-Open No. 2002-146772
[Problems to be solved by the invention]
As a problem common to the respective inventions described in the section of the prior art, apart from steel sheet piles, it is necessary to manufacture and install a spacing-like projection, a specially shaped joint member, a water shielding member or a restraining member, It is necessary to use a water-impervious seal material to improve water-impermeability, a water-impervious water-impervious material, or a grout material, and the like. Construction cost) is expensive.
[0019]
Furthermore, as described above, when a water-blocking sealing material, a water-blocking material having a swelling property, a grout material, or the like is used, the water-blocking performance due to its aging and peeling when an external force acts on the sheet pile wall is reduced. There is a problem of decline.
[0020]
The present invention has been made to solve the problems in the prior art as described above, and is required to take advantage of the shape and characteristics of a steel sheet pile having an asymmetrical joint developed by the present applicant, and to have the casting property and the water shielding property required. And can be realized at relatively low manufacturing and construction costs.Furthermore, it is possible to secure the water barrier performance against steel sheet pile deformation after the water barrier treatment, and to maintain the water barrier performance over a long period of time. An object of the present invention is to provide a sheet pile type steel wall excellent in water barrier property, which is easy to maintain and maintain, and a steel sheet pile suitable for use in the purpose.
[0021]
[Means for Solving the Problems]
In the steel sheet pile according to claim 1 of the present application, the joint shape at the joints at both ends is asymmetrical in the left and right directions, and a flat part near the joints at both ends and in the same direction as the casting normal is formed. A steel sheet pile having an inward facing portion and an outwardly facing joint portion, and a protrusion at a base portion of at least one of the joints, and having a cross-sectional shape aligned in the same direction and capable of being linearly joined. A part or the whole of the projection is made of a material having a lower melting point than other parts of the sheet pile wall.
[0022]
The entire shape of the steel sheet pile may be any of a straight type and a U type (a shape having a web and flanges on both sides thereof).
[0023]
As the low melting point material constituting part or all of the projections, a welding material (fusing material) or a brazing solder (brass brazing or silver brazing) having a lower melting point than steel is suitable.
[0024]
The projection provided at the base of the projection restricts the rotation of the steel sheet pile at the joint.
[0025]
In the steel sheet pile according to claim 2 of the present application, the joint shape at the joints at both ends is asymmetrical in the left and right direction, and a flat part near the joints at both ends and in the same direction as the casting normal is formed. Inward, the other is formed outwardly of the joint portion, the inward projection on the inward joint side base, and the inward rising portion on the outward joint side base, A steel sheet pile that can be linearly joined with its cross-sectional shape aligned in the same direction, wherein part or all of the protrusions are made of a material having a lower melting point than other parts of the sheet pile wall. It is assumed that.
[0026]
That is, the invention according to claim 2 is the steel sheet pile according to claim 1, wherein the steel sheet pile according to claim 1 has an inward projection on a base on an inward joint side as one joint, and an outward joint side on the other joint. Corresponds to the case where the base has an inward rising portion.
[0027]
The sheet pile type steel wall according to claim 3 of the present application is such that the steel sheet piles according to claim 1 or 2 are connected to each other at the joint portion, and the outer surface of the joint portion and the protrusion are continuous in the longitudinal direction. It has a joint portion joined without a gap.
[0028]
As a means for heating the projections when forming the above-mentioned joints, a non-consumable electrode type such as a TIG or a plasma arc is suitable for gas shielded arc welding, and the type of the shield gas is not limited. For example, in the case of joining in water, a method of heating the joining portion using an arc of plasma arc welding is suitable, and in the case of joining in the air, heating with a gas burner, a filler metal or a filler will be used. May be melted.
[0029]
The invention according to claim 4 is the sheet pile steel wall according to claim 2, wherein the sheet pile steel walls are submerged and / or ground in a state where the sides of the sheet pile steel wall having the joints face each other. It is characterized by being provided inside.
[0030]
In order to solve the above-mentioned problem of the prior art, the present applicant has proposed asymmetrical joints 2 and 3 as shown in FIG. 2 (FIG. 2 (a) shows a state where a plurality of steel sheet piles 1 are connected by joints. FIG. 2B is a plan view, and FIG. 2B is an enlarged view of the joint fitting portion). The joint shape of the steel sheet pile 1 shown in FIG.
[0031]
That is, in the fitting portion of the left and right asymmetric joints 2 and 3 shown in FIG. 2, the applicant connects the outer surface 3 b of the outward joint 3 and the inward projection 2 a continuously in the longitudinal direction of the steel sheet pile 1. When the inward projection 2a is made of a material 5a having a lower melting point than the other parts of the steel sheet pile 1 (FIG. 1B), the The following findings were obtained by comparing both the case where the same material as the other parts of the steel sheet pile 1 was used (FIG. 5A).
[0032]
In this case, as a heating means, a method was adopted in which a plasma arc welding apparatus, which is one of non-consumable electrode type gas shielded arc welding, was used to aim at the inward projection 2a in the atmosphere and heat it. .
[0033]
In the former (FIG. 1), the joining material (the low-melting material 5a) melts out before the base material starts melting, and the gap between the outer surface 3b of the outward joint 3 and the inward projection 2a is relatively easily formed. The joining material is formed so as to have no gap and to have water shielding.
[0034]
On the other hand, in the latter case (FIG. 5), the inward projection 2a and the base material are the same material (steel material), and the melting point of the projection is high. Therefore, the projection 2a depends on the direction of the heating arc and the distance from the projection 2a. As shown schematically in FIG. 5 (b), the molten state of the outer joint 3a changes depending on the position in the longitudinal direction of the joint (the outer surface 3b of the outward joint 3 and the inward projection 2a). There is a gap between them and water that can enter.)
[0035]
Alternatively, depending on the direction of the arc, the distance from the projection 2a, and the amount of heat input, a problem may occur in which the root of the inward projection 2a or the outward joint 3 is cut off, though not shown.
[0036]
Therefore, when joining continuously in the longitudinal direction of the steel sheet pile 1, it is necessary to accurately maintain the position and angle of the arc and appropriately adjust the heat input, and to reduce the joining speed to the former (FIG. 1). Unless reduced considerably, it is extremely difficult to avoid the trouble at the time of the joining and to join the outer surface 3b of the outward joint 3 and the inward projection 2a without any gap so as to have water shielding. Was.
[0037]
As described above, the description was made based on the results of the joint joining experiment in the atmosphere.However, in water, compared with the air, the melted member is easily heated and solidified by surrounding water, so that the projections serving as the joining material are melted. In this case, the amount of heat input by the heating arc must be increased.
[0038]
When joining a joint in water without using a low-melting-point material for part or all of the protrusions, as described above, there is more trouble that the flange of the steel sheet pile is perforated or the joint part is scraped off. The steel sheet pile according to the present invention is easily generated and is suitable for joining in water.
[0039]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 shows an embodiment of the invention according to claims 1 and 2, in which U-shaped steel sheet piles 1 having asymmetrical joints 2 and 3 are connected in a single row, and then a joint fitting portion is welded. , A steel wall A is formed.
[0040]
In this example, an inward projection 2a is formed at the base of the steel sheet pile 1 on the inward joint 2 side, and a rising portion 3a that protrudes inward is formed on the base of the outward joint 3 side.
[0041]
Some or all of the inward projections 2a are made of a material 5a having a lower melting point than the other parts, and the inward joint 2 and the outward joint 3 are engaged to form a plurality of steel sheet piles 1. The steel wall A is provided with high water-shielding by being connected and continuously and longitudinally welded between the outer surface 3b on the outward joint 3 side and the protrusion 2a on the inward joint 2 side without any gap. ing.
[0042]
As a method of constructing the steel wall A, a method may be adopted in which the steel sheet pile 1 is constructed underwater and / or underground while fitting the joints 2 and 3 one by one, and then the joints 2 and 3 are joined. A plurality of steel sheet piles 1 are previously connected and joined at a joint portion to prepare a plurality of integrated sheet piles, and the joints 2 and 3 are fitted and installed underwater and / or underground. May be joined.
[0043]
FIG. 3 shows, as another embodiment, a state before and after joining the outer surface 3b of the outward joint 3 and the inward projection 2a when only a part of the inward projection 2a is made of the low melting point material 5a. ing.
[0044]
In the embodiment of FIG. 3, only the side of the inward projection 2a facing the outward joint 3 is made of the low melting point material 5a. For example, a part of the upper part of the inward projection 2a is made of the low melting point material. It is also possible to use the material 5a.
[0045]
As shown in FIG. 3 (a), the method of integrating the low melting point material 5a with the inward projection 2a may be a method using an adhesive or an appropriate base material temperature after the completion of hot rolling of the steel sheet pile 1. , The low-melting point material 5a is poured into a predetermined position in a predetermined shape, and then cooled and cured.
[0046]
FIG. 4 shows another method for replacing a part of the inward projection 2a with the low melting point material 5a. In the case where a steel sheet pile as a base material is prepared so that the inward projection 2a can be fitted with, for example, an intaglio structure, and both are fitted and integrated. It is. An adhesive may be applied to the fitting surface in advance, or both may be fitted and then fastened with screws (not shown).
[0047]
FIG. 6 shows another embodiment of the invention according to claim 1 of the present application. As in the case of the embodiment of FIG. 1, U-shaped steel sheet piles 1 having asymmetrical joints 2 and 3 are connected in one row. Thereafter, the joint fitting portion is welded to form the steel wall A.
[0048]
As a difference from the embodiment of FIG. 1, in the embodiment of FIG. 6, an outward projection 3 c is formed between the rising portion 3 a and the outward joint 3 side. In a state in which the joint 3 is engaged, the outer surface 3b of the outward joint 3 and the protrusion 2a of the inward joint 2 are welded continuously without any gap in the longitudinal direction.
[0049]
The welding location in this case may be between the outward projection 3c and the outer side surface 2b of the inward projection 2 other than the location shown, in which case, a part of the outward projection 3c or The whole is made of a material 5a having a lower melting point than other parts.
[0050]
Also in the embodiment shown in FIG. 6, a modification similar to that shown in FIGS. 3 and 4 with respect to the embodiment shown in FIG. 1, that is, with respect to the outward projection 3c, only the side facing the inward joint 3 has a low melting point. The low-melting point material may be used as a material, or a part of the lower portion of the outward projection 3c in the figure may be made a low-melting material, or the low-melting material may be previously formed into a part or all of the outward projection 3c. A deformed form in which a steel sheet pile as a base material is prepared in advance so that the outward projections 3c can be fitted in, for example, an intaglio structure, and both are fitted and integrated is conceivable. .
[0051]
Also, in any of the embodiments of FIGS. 1 and 6, the projection 2a or the projection 3c may be any as long as it can restrain rotation at the joint portion and the joints 2 and 3 do not easily come off. For example, it may be lower than that shown.
[0052]
Further, the position of the flat portion 4 with respect to the joints 2 and 3 does not interfere with the fitting of the joints 2 and 3 as well as the lowermost end of the inward joint 2 and the uppermost end of the outward joint 3 as shown. If there is no position, there is no particular limitation.
[0053]
FIGS. 7 (a) and 7 (b) show an embodiment of the invention according to claim 4, in which U-shaped steel sheet piles 1 having asymmetric joints 2 and 3 are connected in two rows, and then the steel sheet piles are connected. The joint fitting portions are joined to form a steel wall A in a state where the members 1 face each other in the inward direction with respect to the outermost edge of the sheet pile wall. FIG. 7A shows a case where two rows of sheet pile walls are close to each other, while FIG. 7B shows a case where two rows of sheet pile walls are separated.
[0054]
As a method of constructing steel walls, it is common to separately provide each row underwater and / or underground. However, if possible, construct two rows of steel sheet pile walls at the same time while keeping them apart from each other. Is also good.
[0055]
The feature of this case is that a closed space isolated from the outside is formed on the facing steel sheet pile wall provided in the water and / or the ground in two rows, so that the part provided in the ground is excavated and jointed. Eliminating the earth and sand in the fitting portion and its peripheral portion makes it easy to perform the joining work of the joint fitting portion thereafter.
[0056]
Further, after the water shielding treatment, the closed space is cut off from the outside, so that it can be used for purposes such as monitoring and repairing joint joints.
[0057]
FIGS. 8 (a) and 8 (b) show another embodiment of the invention according to claim 4, in which two U-shaped steel sheet piles 1 having asymmetric joints 2 and 3 are connected to each sheet pile wall. After being welded through a steel material such as a steel plate or an H-section steel and integrated into a single row in a state where they face each other inward with respect to the outermost edge of Joining to form a steel wall A having excellent water barrier properties. 8A shows a case where two U-shaped steel sheet piles 1 are directly welded and integrated, and FIG. 8B shows a case where two U-shaped sheet piles 1 are welded and integrated via an H-shaped steel 7.
[0058]
In this case, the steel sheet pile 1 can be installed underwater and / or underground at the same time, so that the efficiency of construction (casting) can be improved and the steel sheet pile 1 can be installed underwater and / or after being installed underground. Since the interval between the two can be kept constant, it is suitable for introducing a mobile joining machine as shown in FIG. 10, and the efficiency of joining work of the joint fitting portion can be improved.
[0059]
Also, as in the case of the embodiment of FIG. 7, since a closed space is formed that is isolated from the outside world, a portion constructed in the ground is excavated, and soil and sand in the joint fitting portion and its peripheral portion are eliminated. This facilitates the subsequent joining of the joint fitting portion.
[0060]
Further, after the water shielding treatment, the closed space is shut off from the outside, so that it can be used for applications such as monitoring and repairing joint joints.
[0061]
FIG. 9 shows still another embodiment of the invention according to claim 4, wherein two straight steel sheet piles 11 having asymmetrical joints are mutually inwardly directed to the outermost edge of each sheet pile wall. In a confronting manner, the steel plates 12 are welded and integrated via a steel plate 12 and connected in a single row, and then the joint fitting portions are joined to form a steel wall A.
[0062]
Also in this case, similarly to the embodiment of FIG. 8, since two steel sheet piles can be installed underwater and / or underground at the same time, the efficiency of construction (placement) can be improved, and after installation underwater and / or underground. Since the interval between the steel sheet piles 11 can be kept constant, it is suitable for introducing a mobile joining machine as shown in FIG. 10, and the efficiency of joining work of the joint fitting portion can be improved.
[0063]
In addition, since a closed space isolated from the outside world is formed, the part provided in the ground is excavated to remove the earth and sand in the joint fitting part and the surrounding area, thereby joining the joint fitting part thereafter. Construction becomes easy.
[0064]
Further, after the water shielding treatment, the closed space is shut off from the outside, so that it can be used for applications such as monitoring and repairing joint joints.
[0065]
In addition, as the joining method in the above embodiment, as shown in FIGS. 10 and 11, a movable joining machine 8, which can continuously join at a predetermined position at a predetermined joining speed in a longitudinal direction of a steel sheet pile, 9. It is desirable to use an automatic welding robot from the viewpoint of work efficiency, but joining by manual intervention is also possible.
[0066]
In addition, in the joining of the joint fitting portion using the mobile joining machine illustrated in FIGS. 10 and 11, a joining position using water or a gas such as air is used in order to remove foreign matter such as earth and sand that has entered the fitting portion. It is desirable to provide a function of purging immediately before bonding.
[0067]
【The invention's effect】
The steel sheet pile and sheet pile type steel wall of the present invention are configured as described above, and the joint portion of the connected and constructed steel sheet pile has no trouble at the time of joining and is stably joined without gaps, so that steel It is possible to completely prevent intrusion of groundwater and seawater from the joint between the sheet piles.
[0068]
Furthermore, since a swellable water-blocking material or a water-blocking member is not required, the production cost and the construction cost are low, and a steel sheet pile and a steel having various cross-sectional performances by combining with another steel material such as an H-section steel are provided. Walls can be realized.
[0069]
In addition, in the invention according to claim 4, by maintaining a monitoring space for the joined joints, maintenance and inspection and repair of the joints after the completion of the construction are facilitated, and the water barrier performance can be maintained for a long time.
[0070]
Furthermore, when a plurality of rows of steel sheet piles are connected and constructed, the joints can be joined in two rows at the same time, so that the construction time can be shortened and the construction cost can be reduced.
[Brief description of the drawings]
FIG. 1 shows an embodiment of a steel sheet pile and a sheet pile type steel wall according to claims 1 and 2 of the present application, wherein (a) is a plan view showing a state where steel sheet piles having an asymmetric joint are connected. FIGS. 3B and 3C are enlarged views of a main part showing a state of joining.
FIG. 2A is a plan view showing a state in which a plurality of steel sheet piles having an asymmetrical joint to which the present invention is applied are connected by joints, and FIG. 2B is an enlarged view of the joint fitting part.
FIGS. 3 (a) and 3 (b) are plan views of essential parts showing a state of joining in another embodiment of the steel sheet pile and sheet pile type steel wall of the present invention.
FIGS. 4A and 4B are explanatory views showing an example of a method of replacing a part of the inward projection with a low melting point material.
FIGS. 5A and 5B are explanatory diagrams of a defective bonding situation as a comparative example.
FIG. 6 shows another embodiment of the steel sheet pile and sheet pile type steel wall according to claim 1 of the present application, in which (a) is a plan view showing a state where steel sheet piles having asymmetric joints are connected, (b), (c) is an enlarged view of a main part showing a state of joining.
FIGS. 7A and 7B are plan views showing one embodiment of the invention according to claim 4, wherein FIG. 7A shows a case where two rows of sheet pile walls are close to each other, and FIG. If it is.
FIGS. 8A and 8B are plan views showing another embodiment of the invention according to claim 4, wherein FIG. 8A is a case where two U-shaped steel sheet piles are directly welded and integrated, and FIG. This is the case where they are integrated by welding.
FIG. 9 is a plan view showing still another embodiment of the invention according to claim 4;
FIG. 10 is a plan view showing an example of a method of joining a joint fitting portion using a mobile joining machine.
FIG. 11 is a plan view showing another example of a method of joining a joint fitting portion using a mobile joining machine.
FIG. 12 is a plan view showing a water blocking structure in Patent Document 3 as a conventional example.
FIG. 13 is a plan view showing a water blocking structure in Patent Document 4 as a conventional example.
FIG. 14 is a plan view showing a water blocking structure in Patent Document 5 as a conventional example.
FIG. 15 is a plan view showing a water blocking structure in Patent Document 6 as a conventional example.
[Explanation of symbols]
A: steel wall,
DESCRIPTION OF SYMBOLS 1 ... Steel sheet pile, 2 ... Inward joint, 2a ... Inward protrusion, 2b ... Outer surface, 3 ... Outward joint, 3a ... Rise part, 3b ... Outer surface, 3c ... Outward protrusion, 4 ... Flat part 5a: low melting point material, 5b: welding, 6: welding, 7: H-shaped steel, 8: movable joining machine, 8a: welding torch, 8b: traveling rail, 8c: traveling roller, 9: movable joining 9a: welding torch, 9b: pantograph for adjusting the interval between joining machines, 9C: roller for positioning and running, 11: straight steel sheet pile, 12: steel plate

Claims

The joint shape at the joints at both ends is asymmetrical, and a flat portion in the same direction as the casting normal is formed near the joints at both ends, and one is formed inward and the other is formed outward with respect to the flat portion. The joint portion, a steel sheet pile having a protrusion at a base of at least one of the joints, and having a cross-sectional shape aligned in the same direction and capable of being linearly coupled, wherein part or all of the protrusion is a sheet pile. A steel sheet pile made of a material having a lower melting point than other parts of the wall.

The joint shape at the joints at both ends is asymmetrical, and a flat portion in the same direction as the casting normal is formed near the joints at both ends, and one is formed inward and the other is formed outward with respect to the flat portion. The joint portion has an inward protrusion at an inward joint side base and an inward rising portion at the outward joint side base, and has a linear cross-sectional shape in the same direction. A part of or all of the projections is made of a material having a lower melting point than other parts of the sheet pile wall.

The steel sheet pile according to claim 1 or 2, wherein the steel sheet pile is connected at the joint portion, and has a joint portion in which the outer surface of the joint portion and the protrusion are joined continuously in the longitudinal direction without a gap. Sheet steel wall.

The sheet pile type steel according to claim 3, wherein the sheet pile type steel walls are provided underwater and / or in the ground in a state where the side having the joint portion of the sheet pile type steel wall faces each other. Wall.