JP3747594B2

JP3747594B2 - Steel pipe pile joints

Info

Publication number: JP3747594B2
Application number: JP28699797A
Authority: JP
Inventors: 陽登志豊原; 行正江面; 正則清水; 孝一置田
Original assignee: JFE Steel Corp
Current assignee: JFE Steel Corp
Priority date: 1996-10-22
Filing date: 1997-10-20
Publication date: 2006-02-22
Anticipated expiration: 2017-10-20
Also published as: JPH10311028A

Description

【０００１】
【発明の属する技術分野】
本発明は、土木建築分野の鋼管杭に関する技術であって、例えば地滑り対策に用いる鋼管杭、支持杭に用いる鋼管杭の接合に適用されるもので、鋼管杭の接合方法及び鋼管杭の継手に関する。
【０００２】
【従来の技術】
地滑り抑止用の鋼管杭は、地滑りが発生するおそれのある地層の山地、法面、傾斜地にボーリング孔を施工し、このボーリング孔内に鋼管杭を挿入し、孔内にモルタル等を充填して安定化させ、地滑りを起こすような地表部を地層の深部と縫い合わせ結合するものである。このような鋼管杭は、施工場所の条件に応じて例えば直径２００〜６００ｍｍ程度、長さ数十ｍにも及ぶものがある。従って、複数本の鋼管杭を施工現場において接続する必要がある。
【０００３】
一方、市街地等の狭隘な施工条件のもとで、長尺の支持杭を施工する必要がある場合がある。このような時に、例えば、架線や橋梁などの架空構造物が既にある場合や、屋根の下等で、短尺の鋼管杭を多数本接続して地中に沈設しなければなならない場合もある。
従来、一般に、鋼管杭の継手には、つき合わせ溶接継手、スリーブを用いる溶接継手、ねじ継手、フランジ継手等が用いられている。
【０００４】
溶接継手は、溶接施工に長時間を要すると共に、熟練溶接作業員の確保が困難になりつつあり、またＸ線検査等を必要とする問題がある。これに代わる継手としては、例えば特公平７−１３３６８号公報には、テーパねじ継手の現場における接合作業に用いる従来技術が開示されている。現場作業者の目視によって確認しながら継手接合を実施する。また杭の芯合わせのために丸棒を折り曲げた簡単な治具を下杭の頭部に掛け、上杭を下杭の中に案内するようにしたものがある。
【０００５】
このようなテーパねじは、上杭と下杭の芯合わせが容易でなく、上下杭の精度の高い慎重なセッチングを要し、また、ねじの土砂等による汚染とか、ねじの焼き付きや損傷防止に格別の配慮を必要とし、ねじが噛み合わないと施工不良となる等、現場作業に困難性が多く能率的でない。フランジ継手は、外径が大きくなる問題があり、外径が大きくならないように杭端部の外径を絞ることも考えられるが、ボルト挿入やレンチの使用が容易でなく、施工に長時間を要する。
【０００６】
また、特開平９−３８７５号公報、特開平９−１３２９１３号公報には、杭のねじ継手であって雌ねじ側に案内筒を設け、雄ねじ側にこの案内筒内に進入する案内円柱を設け、この案内筒と案内円柱とを嵌合して杭軸を一致させ、ねじの正常な噛み合いを達成しようとするものである。この技術では、ねじの長さより深い案内筒とねじの長さより長い案内円柱とを必要とする。
【０００７】
【発明が解決しようとする課題】
上下の鋼管杭をねじ継手を用いて現場接合する場合に、下杭の施工鉛直精度が悪いと、治具を用いても上下杭のねじがうまく噛み合わず、ねじ部の焼き付け、損傷を生じ、施工不良となる。また施工に長時間を要することとなる。ねじが完全にかみ合わないと、所定の強度が得られず、品質不良となり、その修正対策は非常に困難である。
【０００８】
このねじ継手の軸心を一致させるためにテーパねじを用いる技術では、テーパねじは雄ねじと雌ねじの噛み合い始めに相互のねじ軸に傾きがあると、クロススレッド（ねじ山のかけ違い）が生じ、傾いたままねじを締めつけるとねじ山潰れを発生し、継手の性能が劣化する問題がある。
本発明は上記問題点を解決し、現場施工において、短時間に容易に継手部の心合せができ、確実に強固に接合することができる鋼管杭の接合継手を開発し、これを提供することを目的とする。
【０００９】
また本発明の別の目的は、市街地等における制約された施工条件のもとで、例えば長さ２ｍ程度の短尺の多数本の杭を接続して長尺の杭を施工する場合に、杭の吊り上げ時にねじ部に損傷を与えることなく、上下杭の心出しが容易でねじ込みが簡単であり、接合等の施工が容易で、正確な杭打ちができるほか、杭の逆転によっても継手部が抜け出さない継手を提供することにある。
【００１０】
【課題を解決するための手段】
本発明は、上記問題点を解決するために、次の技術手段を講じたことを特徴とするものである。
本発明の鋼管杭の接合継手の構造は次のとおりである。すなわち、鋼管杭端にそれぞれ設けられ、雄ねじを有する雄側筒体と雌ねじを有する雌側筒体とからなり、ねじは平行ねじの３条以上の多条ねじとし、雄側筒体の先端に前記雌ねじ内径に遊嵌する外径を有する円筒部を設けたことを特徴とする鋼管杭の接合継手を提供する。本発明の接合継手は、鋼管杭の端部に雄雌ねじ結合の筒体を備えたもので、鋼管杭の心合わせを容易にし、結合を迅速にするために、多条ねじを採用する。さらに、心合わせを自動調心するように、雄側筒体の雄ねじより先端側に雌ねじの内径に遊嵌する円筒部を設ける。この円筒部の外径は雌ねじの内径に遊嵌する寸法であり、雄ねじの山を削除した外径寸法を有するものである。そして、雄ねじは多条ねじであるから、雄ねじの始端部がねじ軸に直角な面内に多条ねじの条数分だけ存在し、雌ねじ側もねじ軸に直角な同一断面内に多条ねじの条数分だけ同一位相のねじ山が存在するので、ねじの噛み合い始めが多数位置で起こり、上記円筒部が雌ねじの内径に嵌合して位置きめする作用と相俟って、上下杭の軸心が容易に一致するとともに、ねじの正常な噛み合いが容易に達成される。
【００１１】
この継手構造では、前記円筒部の軸方向の長さは問わない。上下杭を結合する時この円筒部がガイドとなり、上下杭の軸心が一致するのに十分な最小限の寸法があればよく、ねじ長さより長い寸法は全く必要がなく、短い寸法のもので、心出しが容易となる。このような杭は、例えば構造物の下で１本の杭の長さが２ｍ程度というような短尺の杭を多数本連結して数十ｍの長尺の杭を施工するというような場合に好適に用いられる。このような場合には、心合せ治具などの着脱手間をも節約したい場合があり、このような時に特に効果を発揮する。
【００１２】
本発明においては、前記円筒部に代わり、雌側筒体の先端に前記雄ねじの外径に遊嵌する内面円筒部を設けることとしてもよく、心合わせを容易にする効果は上記円筒部と同等である。さらに、前記円筒部に加えて、雌側筒体の先端に前記雄ねじの外径に遊嵌する内面円筒部を設けると、さらに一層心合わせが容易となる。本発明に係る鋼管杭は、上杭を吊り上げてその下端を下杭の上に接触させると自動的に軸心が一致し、心合せの手間を要しない。
【００１３】
また、前記円筒部の先端が当接する内周座を前記雌側筒体の内面に設けると、ねじ込み終了のストッパとしての役割を果たすと共に、ねじの緊結に寄与し、軸方向の大推力伝達機能を持たせることができる。また、前記内面円筒部の先端が直接又は止水ゴムリングを介して当接する外周座を前記雄側筒体外面に設け、上記ストッパ、ねじの緊結、推力の伝達の作用を付与するか、又は水密シール特性を付与することとすると好適である。
【００１４】
また、このような杭は、施工中に逆転をする必要が生ずることがある。従って逆転したときにねじ継手の緩み止めのセットボルトを備える。短尺の杭を多数連結して形成した長尺の杭では継手部が多数あるために、ねじの緩みに特に配慮する必要がある。セットボルトは、雌側筒体の円筒壁にセットボルト装着孔を備え、雄側筒体の円筒部の外周に、セットボルトの先端が嵌入する凹孔、又は、円周鉢巻状の凹溝、又は、円筒の母線に沿う長孔状の凹孔又は凹溝等を設ける。鋼管杭の内外をシールする等の観点から、凹孔は貫通孔でない方がよい。しかし、鋼管杭の内外をシールする必要がない時は、凹孔の代りに貫通孔としてもよい。
【００１５】
このセットボルトによって、上下杭の結合を確実にすると共に、上下杭間の回転トルクの伝達、推力の伝達機能を容易に与えることができる。
セットボルトの装着孔は筒体の中心点対称に１対設け、前記凹孔は筒体の中心点対称にＮ対以上を円周上に等間隔に配置するとよい。但しＮは多条ねじの条数とする。例えば３条ねじでは凹孔は６個以上の偶数個、４条ねじでは８個以上の偶数個、５条ねじでは１０個以上の偶数個とする。このようにすることによって、雄ねじと雌ねじを十分にねじ込んでから、軸方向にねじピッチの半分以下のストロークだけねじを戻すことによって、凹孔とセットボルトとの位置を一致させることができ、セットボルトと凹孔との嵌合寸法精度、相互の配置位置精度を高め、加工精度を確保することが容易となる。
【００１６】
また、このセットボルトの装着部にアイボルトを取りつけて鋼管杭をハンドリングする際の吊り手として利用することもできる。これによって、継手用のねじを有する鋼管杭を吊り込む際に、ねじに損傷を与える恐れがなくなる。さらに、鋼管杭の頭部にヤットコ（雇い杭、杭打等のために杭頭に仮設する補助具）を取りつける場合にその取付ボルト孔として利用することができるように、共通性を持たせた設計とすることによって、多目的に利用することができる。
【００１７】
【発明の実施の形態】
以下図面を参照して本発明の実施の形態を詳細に説明する。図１は本発明の実施例を示すもので、図１（ａ）は本発明の鋼管杭の下端に取付ける雄側筒体である下端部金物２０、図１（ｂ）は鋼管杭の上端に取付ける雌側筒体である上端部金物３０で、それぞれ左半分は外形側面図、右半分は縦断面図である。下端部金物２０は上部円筒２１と下部円筒２３とが上下一体に製作されている。上部円筒２１は鋼管杭１００の外径と等しい外径を有し、その上端には鋼管杭１００との溶接接合１０１のための開先２２を備えている。そして、下部円筒２３は、下杭１１０の上端部金物３０の雌ねじ３３に螺合する雄ねじ２４が形成されている。この雄ねじ２４の先端部には、雄ねじ２４のねじ底径を外径とする円筒部２５が形成されている。上側の鋼管杭１００と下側の鋼管杭１１０とを接合する時、この円筒部２５は雌ねじ３３の内径に遊嵌し、上下杭の軸心を自動的に一致させるように上杭をガイドする。
【００１８】
この円筒部２５の下端面２６は鋼管杭の軸に直角な面をなしている。また、雄ねじ２４の後端には鋼管杭の軸に直角な面からなる外周座２７が設けられている。なお、下端部金物２０の外径面に適宜の孔又は切欠２８などを設け、バー、スパナ、トング等、鋼管杭１００の転回を容易にする工具又は治具等を係合可能にしておくと好ましい。
【００１９】
鋼管杭１１０の上端部金物３０は、鋼管杭１１０と同径の外径を有し、鋼管杭１１０との溶接接合１１１のための円周開先３２を下端に備えている。上端部金物３０の上部には、上記下端部金物２０の雄ねじ２４と螺合する雌ねじ３３が設けられており、雌ねじ３３の下端部に、軸と直角な面を有する内面座３４を形成している。また、雌ねじ３３の上方に内面円筒３８を形成してある。この内面円筒部３８の内径は雌ねじ３３のねじ底の直径と一致しており、雄ねじ２４の外径に遊嵌する。上側の鋼管杭１００と下側の鋼管杭１１０とを接合する時、この内面円筒部３８は雄ねじ２４の外径に遊嵌し、上下杭の軸心を自動的に一致させるように上杭をガイドする。
【００２０】
上端部金物３０の上端に、軸直角面３５を備え、その内周部に面取り部３６を設けている。この実施例では、内面座３４と上端面３５との距離は、前記下端部金物２０の下端面２６と外周座２７との距離よりわずか小さくしてあり、面取り部３６はシールゴムパッキングを介装するシール座を形成しシール性を高めるようになっている。しかし、内面座３４と上端面３５との距離を、前記下端部金物２０の下端面２６と外周座２７との距離より大きく形成し、上端部金物３０の上端面３５と下端部金物２０の外周座２７とが密着し、下端部金物２０の下端面２６と上端部金物３０の内面座３４との間に隙間が生ずるような寸法関係にしてもよい。
【００２１】
なお、図１の実施例では、円筒部２５と内面円筒部３８とは両者を備えたものを示しているが、何れか一方だけとし他方をを省略しても上記心合わせのガイド機能は十分である。両者を備えた方がさらに確実容易である。
雄ねじ２４と雌ねじ３３とは、テーパを持たない平行ねじに形成してあり、かつ３条以上の多条ねじとなっている。平行ねじは、テーパねじに比べて低トルクで接合することができる。また、多条ねじは、１回転する時の軸方向のリードがねじピッチの多条倍となる。従って迅速なねじ込みができる。
【００２２】
上杭の下端（下端部金物２０の下端部）にねじ底径の円筒部２５を設けることにより、雄ねじ２４を雌ねじ３３にねじ込み開始する初期に、円筒部２５がガイドとなってねじの噛み合いを促進助長することができ、ねじ込みが容易となる。ねじ込みにより、上杭の下端面（下端部金物２０の下端面２６）と下杭の内周座３４とを緊密に密着させることによって、杭の継手部の強度及び曲げ剛性を著しく高めることができる。
【００２３】
また、この継手は、雄ねじ２４と雌ねじ３３との螺合部に地下水等が進入するのを止水ゴムリング３７でシールして防止することができるので、ねじの劣化、鋼管杭の結合力の低下を招来するおそれがない。
図２は図１のＡ−Ａ矢視図を示したもので、上端部金物３０の上端面３５の内側に４条ねじの雌ねじ３３が設けられている。図３は図２と比較のために示した従来の１条ねじの平面図である。図２に示した本発明の実施例の４条ねじでは、ねじの始端部３９（仮想線で囲んで示している部分）が、ねじ軸に直角な同一平面内に４個所存在する。一方、この雌ねじに噛み合う雄ねじも同様であるから、雄ねじが雌ねじと噛み合う噛み合い始めにねじの先端はねじ軸に直角な平面内で４点で接触する。従って常に安定した円滑な噛み合い始めが確保され、噛み合い不良を起こすことが全くない。本発明の接合継手は円筒部２５、内面円筒部３８による心合わせガイド機能と、この噛み合い始端部が同一平面内に多点存在することとの相乗効果により、現場における迅速円滑な接合が保証されている。従来の１条ねじを備えた図３では、ねじの始端部３９は１か所しかないから、雄ねじと雌ねじの軸心に傾きがあると噛み合い始めが不円滑となり、本発明のような安定した噛み合い始めを確保することができず、クロススレッドを生ずる恐れがある。
【００２４】
図４〜図６は実施例の接合継手の接合工程を模式的に示した説明図である。
図４は下端部金物２０の雄ねじ２４と上端部金物３０の雌ねじ３３とが噛み合い始める直前の状態を示すものである。下端部金物２０の先端の円筒部２５は雌ねじ３３の内径に嵌合し、上端部金物３０の上端の内部円筒部３８は雄ねじ２４の外径に嵌合し、雄ねじ２４の軸と雌ねじ３３の軸は互いにほぼ同軸に自動的に調心される。同時に、雄ねじ２４と雌ねじ３３の噛み合い始端部は、図２で説明したように、軸に直角な平面内で４点で接する状態になっており、下端部金物２０を捻回すれば直ちに円滑にねじが噛みあう状態になっている。
【００２５】
図５は円滑に迅速にねじ込んでいる途中の状態を示している。図６は、ねじ込みを完了し、下端部金物２０の下端面２６が上端部金物３０内の内面座３４に当接した状態を示している。
図７は、止水ゴムリングを用いる実施例の継手を結合完了した状態を示すもので、鋼管杭１００、１１０の部分縦断面図である。下端部金物２０の下端面２６が上端部金物３０内の内面座３４に当接し、下端部金物２０の外周座２７と上端部金物３０の上端面３５の面取り３６との間に止水ゴムリング８７を装着した例を示している。
【００２６】
図８は本発明に係る鋼管の継手部の曲げ試験を模式的に示すものである。
本発明の鋼管杭の継手は、継手部の曲げモーメントをねじ部で伝達するようにし、下端部金物２０、上端部金物３０等の継手金物の材質としては、鋼管杭の素管強度が５０〜６０ｋｇｆ／ｍｍ² の場合に８０ｋｇｆ／ｍｍ² 級の鋼を用い、鋼管杭に溶接接合するものとする。継手の強度は、危険断面における断面縁降伏モーメントが鋼管杭の素管の断面縁降伏モーメント以上とし、危険断面における全塑性モーメントが鋼管杭の素管の全塑性モーメント以上とし、ねじの縁せん断降伏モーメントが鋼管杭の素管の全塑性モーメント以上とする。なお、継手部の断面剛性は鋼管杭の素管の断面剛性以上とする。
【００２７】
図８に示すように、鋼管杭（母管）１００、１１０を、継手部１２０を中央にして、支持部１２１で支持し、継手部１２０を挟む２位置１２２、１２２に載荷梁１２３を介して荷重１２４を負荷し継手部１２０の曲げ特性を試験した。供試材は、外経３００ｍｍ、肉厚１９．５ｍｍのＳＫＫ４９０材からなる鋼管杭を用い、曲げモーメントと変位との関係を図９に示した。なお、この試験では現場施工の継手接合許容値を考慮して下端部金物の下端面と上端部金物の内周座の隙間を５ｍｍとしている。図９中の実線は試験値、破線は計算値である。継手部の縁降伏曲げモーメントＭｙ、全塑性モーメントＭｐ、断面剛性共に素管の特性を上回っており、優れた特性を示している。
【００２８】
図１０は本発明の継手の別の実施例である。鋼管杭１００の下端に取付ける下端部金物４０と、鋼管杭１１０の上端に取付ける上端部金物５０が組み合わされている。下端部金物４０は鋼管杭１００に溶接接合１０１されており、雄ねじ４２の先端部には、ねじ底径を外径とする円筒部４５が形成されている。その下端面４６は鋼管杭の軸に直角な面をなしている。また、雄ねじ４２の後端にはシール座４７が設けられている。
【００２９】
鋼管杭１１０の上端部金物５０は、鋼管杭１１０と溶接接合１１１され、内径に雌ねじ５３が設けられている。雌ねじ５３の下方に、内面円筒面５５が形成されており、上記雄ねじの下方の円筒部４５が進入する。
雄ねじ４２と雌ねじ５３とは、テーパを持たない平行ねじに形成してあり、かつ３条以上の多条ねじとなっている。平行ねじは、テーパねじに比べて低トルクで接合することができる。また、多条ねじは、１回転する時の軸方向のリードがねじピッチの多条倍となる。従って迅速なねじ込みができる。
【００３０】
雄ねじ４２を雌ねじ５３にねじ込む時に、ねじ込み前に円筒部４５が雌ねじ５３の内径に沿うガイドとなるので上下杭の心出しが容易である。ねじ込みにより、下端部金物４０の下端面４６と上端部金物５０の内周座５６とを緊密に密着させることによって、鋼管杭の接合継手部の強度及び曲げ剛性を著しく高めることができる。
【００３１】
下端部金物４０の円筒部４５の外周面に凹孔４８が設けられており、上端部金物５０の円筒壁５４にセットボルト装着孔５８が設けられている。図１１に示すように、凹孔４８にセットボルト装着孔５８を対向させ、このセットボルト装着孔５８にセットボルト６０をねじ込み、下杭と上杭の回り止めを形成し、上杭を逆転させても雄ねじ４２が抜け出さないようにする。図１１のＢ−Ｂ矢視断面図を図１２に示した。この例はねじが４条ねじの場合を示している。セットボルトの装着孔５８は上端部金物５０の円筒壁５４に中心点対称に１対を設けている。下端部金物４０には、凹孔４８を中心点対称に４対つまり８個を円周上に等間隔に配置している。このようにすると、下端部金物を中心角で４５度以内（円周の８分の１以内）逆転させると、何れかの凹孔４８とセットボルト装着孔５８が対向する。一般的にはＮ条ねじの時、凹孔４８を円周上にＮ対以上の偶数箇配置すればよい。このようにすると、ねじピッチの２分の１以下の軸方向移動量の逆転によりセットボルトをセットすることができ、凹孔の直径、配置位置とセットボルトの直径、配置位置との関係を精度よく定めることができる。また、ねじピッチは通常８ｍｍ程度であるから、ねじを軸方向に４ｍｍ以内戻すことにより達成できる。これより、前記の施工上の継手接合部の隙間の許容値（５ｍｍ）以内となり、十分な継手強度を確保することができる。
【００３２】
なお、この実施例では、凹孔４８を円形孔とし、貫通孔でない例を示しているが、鋼管杭の使用条件等に応じて、凹孔の代わりに、貫通孔、円周凹溝、軸方向凹溝、その他任意の変形を用いることを制限するものではない。また、セットボルト装着孔５８の位置、数、大きさ等も上記実施例に制約されるわけではなく、予備孔等を設けても差し支えない。図１３はこのセットボルトのねじ込みを示す斜視図である。
【００３３】
図１４、１５は、上下杭の心合わせの説明図である。下杭の上端部金物５０と上杭の下端部金物４０との軸心が一致しないと、わずかな軸心狂いでも大直径の杭では、接合端部に大きな隙間７０を生ずる。例えば、下杭の鉛直精度が１／２００の時、直径６００ｍｍの杭では、継手接合面の隙間７０は３ｍｍとなる。ねじは、図１５に示す４点７１、７２、７３、７４が同時にかみ合わないと接合が不可能になる。本発明では、下端部金物の雄ねじの先端の円筒部と上端部金物の雌ねじの先端部の内面円筒部の何れか一方又は両方、及び本発明の多条ねじ構造との相乗作用により、この心出しは極めて容易、確実である。また、多状ねじはリードが非常に大きく、接合が迅速である。従って、本発明の鋼管杭の接合継手は、省力、省時間、安全、確実、で信頼性が高く、迅速施工に最適である。
【００３４】
また、下端部金物の下端の円筒部は、図１６に示すように、杭１００を吊具１３０で上方１３１に吊り上げる時、ねじが床面１３２に接触せずねじ部が保護されるという特徴がある。
【００３５】
【発明の効果】
本発明の鋼管杭の接合継手は以上のように構成されているので、次の優れた効果を奏する。すなわち、鋼管杭の自動調心作用があり、鋼管杭の現場接続の施工時間を短縮することができる。また下杭の施工精度に影響されることなく迅速に正確に施工することができる。ねじの噛み合いを極めて円滑にすることができ、省力的で確実な施工が可能となり、継手品質を向上させることができる。
【００３６】
また本発明の他の実施態様では、杭の吊り上げの時にねじ部に損傷を与えなることなく、上下杭の心出しが容易でねじ込みが簡単であり、接合等の施工が容易で、正確な杭打ちができるほか、杭の逆転によっても継手部が抜け出さない。
【図面の簡単な説明】
【図１】実施例の接合継手の側面図、縦断面図である。
【図２】実施例の接合継手のねじ始端部の平面図である。
【図３】従来例の接合継手のねじ始端部の平面図である。
【図４】実施例の接合継手の接合工程の説明図である。
【図５】実施例の接合継手の接合工程の説明図である。
【図６】実施例の接合継手の接合工程の説明図である。
【図７】実施例の継手の接合状態を示す部分縦断面図である。
【図８】実施例の継手の曲げ試験の説明図である。
【図９】実施例の継手の曲げ性能を示すグラフである。
【図１０】他の実施例の継手金物の縦断面図である。
【図１１】図１１の実施例の継手金物の縦断面図である。
【図１２】図１１の実施例のＡ−Ａ矢視図である。
【図１３】図１１の実施例の斜視図である。
【図１４】継手金物の心出しの説明図である。
【図１５】継手金物の心出しの説明図である。
【図１６】杭の吊り上げの説明図である。
【符号の説明】
２０下端部金物
２１上部円筒
２２開先
２３下部円筒
２４雄ねじ
２５円筒部
２６下端面
２７外周座
２８孔又は切欠
３０上端部金物
３１外周部
３２円周開先
３３雌ねじ
３４内面座
３５上端面
３６面取り
３７止水ゴムリング
３８内面円筒部
３９ねじの始端部
４０下端部金物
４２雄ねじ
４５円筒部
４６下端部
４７上端面
４８凹孔又は凹溝
５０上端部金物
５３雌ねじ
５４円筒壁
５５内面（円筒面）
５６内周座
５８セットボルト装着孔
６０セットボルト
７０隙間
７１、７２、７３、７４点
１００、１１０鋼管杭
１０１、１１１溶接接合
１２０継手部
１２１支持部
１２２荷重点
１２３梁
１２４荷重
１３０吊具
１３１吊上げ
１３２床面[0001]
BACKGROUND OF THE INVENTION
The present invention is a technology related to steel pipe piles in the field of civil engineering and construction, and is applied to, for example, steel pipe piles used for landslide countermeasures, steel pipe piles used for support piles, and relates to a steel pipe pile joining method and a steel pipe pile joint. .
[0002]
[Prior art]
For steel pipe piles for landslide prevention, bore holes are constructed in mountainous, sloped, and sloped areas where landslides may occur, steel pipe piles are inserted into the boreholes, and mortar is filled in the holes. Stabilize and connect the surface part that causes landslide to the deep part of the formation. Such steel pipe piles include those having a diameter of about 200 to 600 mm and a length of several tens of meters depending on the conditions of the construction site. Therefore, it is necessary to connect a plurality of steel pipe piles at the construction site.
[0003]
On the other hand, it may be necessary to construct a long support pile under narrow construction conditions such as in urban areas. In such a case, for example, there are cases where an aerial structure such as an overhead wire or a bridge already exists, or there are cases where a large number of short steel pipe piles must be connected and submerged under the roof.
Conventionally, butt-welded joints, welded joints using sleeves, threaded joints, flange joints, and the like are generally used as joints for steel pipe piles.
[0004]
Welded joints require a long time for welding, and it is becoming difficult to secure skilled welding workers, and there are problems that require X-ray inspection and the like. As an alternative joint, for example, Japanese Patent Publication No. 7-13368 discloses a conventional technique used for joining work on a taper screw joint in the field. Perform joint joining while confirming by visual inspection of field workers. There is also a simple jig that folds a round bar for centering the pile and hangs it on the head of the lower pile to guide the upper pile into the lower pile.
[0005]
Such taper screws are not easy to align the upper and lower piles, and require high-precision and careful setting of the upper and lower piles. Special considerations are required, and if the screws are not meshed, the work will be poor. Flange joints have a problem that the outer diameter increases, and it is possible to reduce the outer diameter of the pile end so that the outer diameter does not increase, but it is not easy to insert bolts or use a wrench, and it takes a long time for construction. Cost.
[0006]
Further, in JP-A-9-3875 and JP-A-9-132913, a threaded joint of a pile is provided with a guide cylinder on the female thread side, and a guide cylinder that enters the guide cylinder on the male thread side, The guide cylinder and the guide cylinder are fitted to match the pile shaft to achieve normal engagement of the screws. This technique requires a guide cylinder deeper than the length of the screw and a guide cylinder longer than the length of the screw.
[0007]
[Problems to be solved by the invention]
When the upper and lower steel pipe piles are joined on site using threaded joints, if the vertical accuracy of the lower pile is poor, the screws of the upper and lower piles do not mesh well even when using a jig, and the screw part is seized and damaged, It becomes construction failure. Moreover, a long time will be required for construction. If the screws are not completely engaged, a predetermined strength cannot be obtained, resulting in poor quality, and it is very difficult to take corrective measures.
[0008]
In the technique using a taper screw to match the axial center of this threaded joint, if the taper screw has an inclination in the mutual screw shaft at the beginning of meshing of the male screw and the female screw, a cross thread (difference in the thread) occurs. If the screw is tightened while tilted, the thread will be crushed and the joint performance will deteriorate.
The present invention solves the above problems, and develops and provides a steel pipe pile joint that can be easily centered in a short time and can be firmly and securely joined in field construction. With the goal.
[0009]
Another object of the present invention is to connect a plurality of short piles having a length of, for example, about 2 m under construction conditions restricted in an urban area or the like. The upper and lower piles can be easily centered and screwed in easily without damaging the threaded part during lifting, and it is easy to join and perform accurate pile driving. There is no joint to provide.
[0010]
[Means for Solving the Problems]
The present invention is characterized by taking the following technical means in order to solve the above problems.
The structure of the steel pipe pile joint according to the present invention is as follows. That is, each of the steel pipe pile ends is provided with a male cylinder having a male thread and a female cylinder having a female thread. The screw is a multi-threaded thread of three or more parallel threads, and is attached to the tip of the male cylinder. Provided is a steel pipe pile joint, wherein a cylindrical portion having an outer diameter loosely fitted to the inner diameter of the female screw is provided. The joint joint of the present invention is provided with a male and female threaded cylinder at the end of a steel pipe pile, and employs multi-threaded screws to facilitate centering of the steel pipe pile and quick coupling. Further, a cylindrical portion that is loosely fitted to the inner diameter of the female screw is provided on the tip side of the male screw of the male cylinder so as to automatically align the center. The outer diameter of the cylindrical portion is a size that fits loosely into the inner diameter of the female screw, and has an outer diameter that eliminates the threads of the male screw. Since the male thread is a multi-threaded thread, the start end of the male thread is present in the plane perpendicular to the screw axis by the number of the multi-threaded thread, and the female thread side is also within the same cross section perpendicular to the threaded axis. Since there are as many threads with the same phase as the number of threads, the beginning of meshing of the screw occurs at a number of positions, coupled with the effect that the cylindrical part is fitted to the inner diameter of the female thread and positioned, The shaft centers are easily matched and normal engagement of the screws is easily achieved.
[0011]
In this joint structure, the axial length of the cylindrical portion is not limited. This cylindrical part serves as a guide when connecting the upper and lower piles, and it is sufficient that there is a minimum dimension sufficient for the axis centers of the upper and lower piles to be aligned. , Easy to center. Such a pile is used when, for example, a long pile of several tens of meters is constructed by connecting a number of short piles having a length of about 2 m under the structure. Preferably used. In such a case, it may be desired to save labor for attaching and detaching a centering jig and the like, which is particularly effective in such a case.
[0012]
In the present invention, instead of the cylindrical portion, an inner cylindrical portion loosely fitted to the outer diameter of the male screw may be provided at the tip of the female side cylindrical body, and the effect of facilitating the centering is equivalent to the cylindrical portion. It is. Furthermore, in addition to the cylindrical portion, if an inner surface cylindrical portion that loosely fits to the outer diameter of the male screw is provided at the tip of the female side cylindrical body, alignment is further facilitated. In the steel pipe pile according to the present invention, when the upper pile is lifted and its lower end is brought into contact with the lower pile, the axis centers automatically coincide with each other, so that the labor of alignment is not required.
[0013]
Further, when an inner peripheral seat with which the tip of the cylindrical portion abuts is provided on the inner surface of the female cylindrical body, it serves as a stopper for screwing completion and contributes to tightening of the screw, and a large thrust transmission function in the axial direction Can be given. In addition, an outer peripheral seat on which the tip of the inner cylindrical portion abuts directly or via a water blocking rubber ring is provided on the outer surface of the male cylinder, and the stopper, screw tightening, thrust transmission action is applied, or It is preferable to provide a watertight seal characteristic.
[0014]
Also, such piles may need to be reversed during construction. Therefore, a set bolt for preventing loosening of the threaded joint is provided when the motor is reversed. Since long piles formed by connecting a large number of short piles have many joints, special consideration must be given to loosening of screws. The set bolt is provided with a set bolt mounting hole in the cylindrical wall of the female side cylindrical body, and the outer periphery of the cylindrical part of the male side cylindrical body is a concave hole into which the tip of the set bolt is fitted, or a circumferential headband-shaped concave groove, Alternatively, a long hole-like concave hole or groove along the cylindrical bus is provided. From the standpoint of sealing the inside and outside of the steel pipe pile, the recessed hole should not be a through hole. However, when it is not necessary to seal the inside and outside of the steel pipe pile, a through hole may be used instead of the concave hole.
[0015]
With this set bolt, it is possible to ensure the connection of the upper and lower piles and to easily provide the rotational torque transmission and thrust transmission functions between the upper and lower piles.
A pair of mounting holes for the set bolts may be provided symmetrically with respect to the center point of the cylindrical body, and N or more pairs of the concave holes may be arranged at equal intervals on the circumference with respect to the central point of the cylindrical body. N is the number of multi-threaded threads. For example, in the case of a three-thread screw, the number of recess holes is six or more even numbers, in the case of a four-thread screw, eight or more even numbers, and in the case of a five-thread screw, ten or more even numbers. By doing so, the male screw and female screw are fully screwed in, and then the screw is returned in the axial direction by a stroke less than half of the screw pitch, so that the position of the concave hole and the set bolt can be matched. It becomes easy to secure the processing accuracy by increasing the fitting dimension accuracy between the bolt and the recessed hole and the mutual arrangement position accuracy.
[0016]
Moreover, it can also utilize as a suspension hand at the time of handling a steel pipe pile by attaching an eyebolt to the mounting part of this set bolt. This eliminates the risk of damaging the screw when suspending a steel pipe pile having a joint screw. In addition, when attaching Yatco (an auxiliary tool temporarily installed on the pile head for hiring piles, pile driving, etc.) to the head of the steel pipe pile, it was made common so that it could be used as its mounting bolt hole. By designing, it can be used for multiple purposes.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows an embodiment of the present invention. FIG. 1 (a) is a lower end hardware 20 which is a male cylinder attached to the lower end of the steel pipe pile of the present invention, and FIG. 1 (b) is an upper end of the steel pipe pile. In the upper end hardware 30 which is a female side cylinder to be attached, the left half is an external side view and the right half is a longitudinal sectional view. The lower end hardware 20 is made of an upper cylinder 21 and a lower cylinder 23 that are integrally formed vertically. The upper cylinder 21 has an outer diameter equal to the outer diameter of the steel pipe pile 100, and a groove 22 for welding joint 101 with the steel pipe pile 100 is provided at the upper end thereof. The lower cylinder 23 is formed with a male screw 24 that is screwed into the female screw 33 of the upper end hardware 30 of the lower pile 110. A cylindrical portion 25 whose outer diameter is the bottom diameter of the male screw 24 is formed at the tip of the male screw 24. When the upper steel pipe pile 100 and the lower steel pipe pile 110 are joined, the cylindrical portion 25 is loosely fitted to the inner diameter of the female thread 33 and guides the upper pile so that the axial centers of the upper and lower piles are automatically aligned. .
[0018]
The lower end surface 26 of the cylindrical portion 25 forms a surface perpendicular to the axis of the steel pipe pile. An outer peripheral seat 27 having a surface perpendicular to the axis of the steel pipe pile is provided at the rear end of the male screw 24. In addition, when an appropriate hole or notch 28 is provided on the outer diameter surface of the lower end hardware 20, a tool, a jig, or the like that facilitates turning of the steel pipe pile 100 such as a bar, a spanner, or a tong can be engaged. preferable.
[0019]
The upper end hardware 30 of the steel pipe pile 110 has the same outer diameter as that of the steel pipe pile 110 and is provided with a circumferential groove 32 for welding joint 111 with the steel pipe pile 110 at the lower end. On the upper part of the upper end hardware 30, a female screw 33 is provided to be engaged with the male screw 24 of the lower end hardware 20, and an inner surface seat 34 having a surface perpendicular to the axis is formed on the lower end of the female screw 33. Yes. Further, an inner cylinder 38 is formed above the female screw 33. The inner cylindrical portion 38 has an inner diameter that matches the diameter of the bottom of the female screw 33 and is loosely fitted to the outer diameter of the male screw 24. When the upper steel pipe pile 100 and the lower steel pipe pile 110 are joined, the inner cylindrical portion 38 is loosely fitted to the outer diameter of the male screw 24, and the upper pile is attached so that the axis centers of the upper and lower piles are automatically aligned. To guide.
[0020]
The upper end of the upper end hardware 30 is provided with an axially perpendicular surface 35, and a chamfered portion 36 is provided on the inner periphery thereof. In this embodiment, the distance between the inner surface seat 34 and the upper end surface 35 is slightly smaller than the distance between the lower end surface 26 of the lower end hardware 20 and the outer peripheral seat 27, and the chamfered portion 36 interposes a seal rubber packing. A seal seat is formed to enhance the sealing performance. However, the distance between the inner surface seat 34 and the upper end surface 35 is made larger than the distance between the lower end surface 26 and the outer periphery seat 27 of the lower end hardware 20, and the upper end surface 35 of the upper end hardware 30 and the outer periphery of the lower end hardware 20. The dimensional relationship may be such that the seat 27 is in close contact and a gap is formed between the lower end surface 26 of the lower end hardware 20 and the inner surface seat 34 of the upper end hardware 30.
[0021]
In the embodiment shown in FIG. 1, the cylindrical portion 25 and the inner cylindrical portion 38 are shown as having both, but the centering guide function is sufficient even if only one of them is omitted and the other is omitted. It is. It is easier and more reliable to have both.
The male screw 24 and the female screw 33 are formed as parallel screws having no taper, and are three or more multi-threaded screws. The parallel screw can be joined with a lower torque than the taper screw. Further, in the multi-thread screw, the lead in the axial direction when rotating once is a multiple thread multiple of the thread pitch. Therefore, quick screwing is possible.
[0022]
By providing the cylindrical portion 25 having a screw bottom diameter at the lower end of the upper pile (the lower end portion of the lower end hardware 20), the cylindrical portion 25 serves as a guide to engage the screw at the initial stage when the male screw 24 starts to be screwed into the female screw 33. It can be facilitated and facilitated. The strength and bending rigidity of the joint portion of the pile can be remarkably increased by tightly bringing the lower end surface of the upper pile (the lower end surface 26 of the lower end hardware 20) and the inner peripheral seat 34 of the lower pile into close contact by screwing. .
[0023]
In addition, this joint can prevent groundwater and the like from entering the threaded portion between the male screw 24 and the female screw 33 by sealing with a water-stop rubber ring 37, so that the deterioration of the screw and the binding force of the steel pipe pile can be prevented. There is no risk of a decline.
FIG. 2 is a view taken along the line A-A of FIG. 1, and a female thread 33 of a four-thread thread is provided inside the upper end surface 35 of the upper end hardware 30. FIG. 3 is a plan view of a conventional single thread shown for comparison with FIG. In the four-thread screw of the embodiment of the present invention shown in FIG. 2, there are four screw start end portions 39 (portions surrounded by phantom lines) in the same plane perpendicular to the screw axis. On the other hand, the same applies to the male screw that meshes with the female screw. Therefore, at the beginning of meshing when the male screw meshes with the female screw, the tip of the screw contacts at four points in a plane perpendicular to the screw axis. Accordingly, a stable and smooth start of meshing is always ensured, and no meshing failure occurs at all. The joint joint of the present invention ensures quick and smooth joining in the field by the synergistic effect of the centering guide function by the cylindrical portion 25 and the inner cylindrical portion 38 and the presence of the meshing start end portions in the same plane. ing. In FIG. 3 provided with a conventional single thread, since there is only one screw start end 39, if the axial center of the male screw and female screw is inclined, the meshing becomes unsmooth and stable as in the present invention. The start of meshing cannot be ensured, and there is a risk of cross-threading.
[0024]
4-6 is explanatory drawing which showed typically the joining process of the joint joint of an Example.
FIG. 4 shows a state immediately before the male screw 24 of the lower end hardware 20 and the female screw 33 of the upper end hardware 30 start to engage with each other. The cylindrical portion 25 at the tip of the lower end fitting 20 is fitted to the inner diameter of the female screw 33, the inner cylindrical portion 38 at the upper end of the upper end fitting 30 is fitted to the outer diameter of the male screw 24, and the shaft of the male screw 24 and the female screw 33 are fitted. The axes are automatically aligned approximately coaxial with each other. At the same time, as described with reference to FIG. 2, the meshing start end portion of the male screw 24 and the female screw 33 is in contact with four points in a plane perpendicular to the axis. Screws are engaged.
[0025]
FIG. 5 shows a state in the middle of being screwed smoothly and quickly. FIG. 6 shows a state in which the screwing is completed and the lower end surface 26 of the lower end hardware 20 is in contact with the inner surface seat 34 in the upper end hardware 30.
FIG. 7 is a partial vertical cross-sectional view of the steel pipe piles 100 and 110, showing a state in which the joint of the embodiment using the water blocking rubber ring is completed. The lower end surface 26 of the lower end hardware 20 abuts on the inner surface seat 34 in the upper end hardware 30, and a water stop rubber ring is provided between the outer peripheral seat 27 of the lower end hardware 20 and the chamfer 36 of the upper end surface 35 of the upper end hardware 30. The example which attached 87 is shown.
[0026]
FIG. 8 schematically shows a bending test of a joint portion of a steel pipe according to the present invention.
In the steel pipe pile joint of the present invention, the bending moment of the joint portion is transmitted by the thread portion, and the material strength of the joint hardware such as the lower end hardware 20 and the upper end hardware 30 is 50 to 50%. In the case of 60 kgf / mm ² , 80 kgf / mm ² grade steel is used and welded to the steel pipe pile. The strength of the joint is such that the cross-section edge yield moment at the critical section is greater than or equal to the cross-section edge yield moment of the steel pipe pile, the total plastic moment at the critical section is greater than or equal to the total plastic moment of the steel pipe pile, and the thread edge shear yield The moment shall be greater than the total plastic moment of the steel pipe pile. In addition, the cross-sectional rigidity of a joint part shall be more than the cross-sectional rigidity of the raw pipe of a steel pipe pile.
[0027]
As shown in FIG. 8, the steel pipe piles (base pipes) 100 and 110 are supported by the support part 121 with the joint part 120 in the center, and are loaded via loading beams 123 at two positions 122 and 122 sandwiching the joint part 120. The bending characteristic of the joint part 120 was tested by applying a load 124. As a test material, a steel pipe pile made of SKK490 material having an outer diameter of 300 mm and a wall thickness of 19.5 mm was used, and the relationship between the bending moment and the displacement is shown in FIG. In this test, the clearance between the lower end surface of the lower end hardware and the inner peripheral seat of the upper end hardware is set to 5 mm in consideration of the joint joint allowable value on site construction. The solid line in FIG. 9 is the test value, and the broken line is the calculated value. The edge yield bending moment My, the total plastic moment Mp, and the cross-sectional rigidity of the joint part exceed the characteristics of the bare pipe, and show excellent characteristics.
[0028]
FIG. 10 shows another embodiment of the joint of the present invention. The lower end hardware 40 attached to the lower end of the steel pipe pile 100 and the upper end hardware 50 attached to the upper end of the steel pipe pile 110 are combined. The lower end metal part 40 is welded and joined 101 to the steel pipe pile 100, and a cylindrical part 45 having a screw bottom diameter as an outer diameter is formed at the tip of the male screw 42. The lower end surface 46 forms a surface perpendicular to the axis of the steel pipe pile. A seal seat 47 is provided at the rear end of the male screw 42.
[0029]
The upper end hardware 50 of the steel pipe pile 110 is welded and joined to the steel pipe pile 110, and a female screw 53 is provided on the inner diameter. An inner cylindrical surface 55 is formed below the female screw 53, and the cylindrical portion 45 below the male screw enters.
The male screw 42 and the female screw 53 are formed as parallel screws having no taper, and are three or more multi-threaded screws. The parallel screw can be joined with a lower torque than the taper screw. Further, in the multi-thread screw, the lead in the axial direction when rotating once is a multiple thread multiple of the thread pitch. Therefore, quick screwing is possible.
[0030]
When the male screw 42 is screwed into the female screw 53, the cylindrical portion 45 serves as a guide along the inner diameter of the female screw 53 before screwing, so that the upper and lower piles can be easily centered. By screwing, the lower end face 46 of the lower end fitting 40 and the inner peripheral seat 56 of the upper end fitting 50 are brought into close contact with each other, whereby the strength and bending rigidity of the joint joint portion of the steel pipe pile can be remarkably increased.
[0031]
A concave hole 48 is provided in the outer peripheral surface of the cylindrical portion 45 of the lower end hardware 40, and a set bolt mounting hole 58 is provided in the cylindrical wall 54 of the upper end hardware 50. As shown in FIG. 11, the set bolt mounting hole 58 is made to face the concave hole 48, and the set bolt 60 is screwed into the set bolt mounting hole 58 to form a detent between the lower pile and the upper pile, and the upper pile is reversed. Even so, the male screw 42 is prevented from coming out. A cross-sectional view taken along the line BB in FIG. 11 is shown in FIG. This example shows a case where the screw is a four-thread screw. A pair of mounting holes 58 for the set bolts are provided on the cylindrical wall 54 of the upper end hardware 50 symmetrically about the center point. In the lower end hardware 40, four pairs, that is, eight concave holes 48 are arranged at equal intervals on the circumference. In this manner, when the lower end hardware is reversed within 45 degrees (within 1/8 of the circumference) by the central angle, any of the recessed holes 48 and the set bolt mounting holes 58 face each other. In general, in the case of N threads, the concave holes 48 may be arranged in an even number of N pairs or more on the circumference. In this way, the set bolt can be set by reversing the axial movement less than one-half of the screw pitch, and the accuracy of the relationship between the diameter of the recessed hole, the position of the set bolt and the diameter of the set bolt, and the position of the set Can be well defined. Further, since the screw pitch is usually about 8 mm, it can be achieved by returning the screw within 4 mm in the axial direction. Thereby, it becomes less than the tolerance (5 mm) of the clearance gap of the joint joint part in the construction, and sufficient joint strength can be ensured.
[0032]
In addition, in this Example, although the concave hole 48 is made into a circular hole and the example which is not a through-hole is shown, according to the use conditions etc. of a steel pipe pile, a through-hole, a circumferential concave groove, a shaft are used instead of a concave hole. The use of directional grooves or any other deformation is not limited. Further, the position, number, size and the like of the set bolt mounting hole 58 are not limited to the above embodiment, and a spare hole or the like may be provided. FIG. 13 is a perspective view showing screwing of the set bolt.
[0033]
14 and 15 are explanatory diagrams of the alignment of the upper and lower piles. If the axial centers of the upper end hardware 50 of the lower pile and the lower end hardware 40 of the upper pile do not coincide with each other, a large gap 70 is generated at the joint end in a large-diameter pile even if a slight axial misalignment occurs. For example, when the vertical accuracy of the lower pile is 1/200, in a pile having a diameter of 600 mm, the gap 70 on the joint joint surface is 3 mm. The screws cannot be joined unless the four points 71, 72, 73, and 74 shown in FIG. In the present invention, this center is formed by a synergistic effect with one or both of the cylindrical portion at the tip of the male screw at the lower end hardware and the inner cylindrical portion at the tip of the female screw at the upper end hardware, and the multi-thread structure of the present invention. The dispensing is extremely easy and reliable. In addition, the multi-threaded screw has a very large lead and can be joined quickly. Therefore, the steel pipe pile joint of the present invention is labor-saving, time-saving, safe, reliable, highly reliable, and optimal for rapid construction.
[0034]
Further, as shown in FIG. 16, the cylindrical portion at the lower end of the lower end hardware is characterized in that when the pile 100 is lifted upward 131 by the lifting tool 130, the screw does not contact the floor surface 132 and the screw portion is protected. is there.
[0035]
【The invention's effect】
Since the bonded joint of the steel pipe pile of the present invention is configured as described above, the following excellent effects are exhibited. That is, there is an automatic alignment action of the steel pipe pile, and the construction time for the on-site connection of the steel pipe pile can be shortened. Moreover, it can be constructed quickly and accurately without being affected by the construction accuracy of the lower pile. Engagement of the screws can be made extremely smooth, labor-saving and reliable construction is possible, and joint quality can be improved.
[0036]
In another embodiment of the present invention, the piles are not damaged when the pile is lifted, the upper and lower piles are easily centered and screwed in easily, and the construction such as joining is easy and accurate. In addition to hammering, the joints will not come out even when the piles are reversed.
[Brief description of the drawings]
FIG. 1 is a side view and a longitudinal sectional view of a joint joint according to an embodiment.
FIG. 2 is a plan view of a screw start end portion of a joint joint according to an embodiment.
FIG. 3 is a plan view of a screw start end portion of a conventional joint.
FIG. 4 is an explanatory diagram of a joining process of a joint joint according to an embodiment.
FIG. 5 is an explanatory diagram of a joining process of a joint joint according to an embodiment.
FIG. 6 is an explanatory diagram of a joining process of a joint joint according to an embodiment.
FIG. 7 is a partial longitudinal sectional view showing a joined state of the joint of the example.
FIG. 8 is an explanatory diagram of a bending test of a joint of an example.
FIG. 9 is a graph showing the bending performance of the joint of the example.
FIG. 10 is a longitudinal sectional view of a joint metal fitting according to another embodiment.
FIG. 11 is a longitudinal sectional view of the joint hardware of the embodiment of FIG.
12 is an AA arrow view of the embodiment of FIG.
13 is a perspective view of the embodiment of FIG.
FIG. 14 is an explanatory view of the centering of the joint hardware.
FIG. 15 is an explanatory view of the centering of the joint hardware.
FIG. 16 is an explanatory diagram of lifting a pile.
[Explanation of symbols]
20 Lower end hardware 21 Upper cylinder 22 Groove 23 Lower cylinder 24 Male screw 25 Cylindrical part 26 Lower end surface 27 Outer peripheral seat 28 Hole or notch 30 Upper end hardware 31 Outer peripheral part 32 Female groove 34 Inner face seat 35 Upper end face 36 Chamfer 37 Stop Water rubber ring 38 Internal cylindrical portion 39 Screw start end 40 Lower end hardware 42 Male screw 45 Cylindrical portion 46 Lower end 47 Upper end surface 48 Recessed hole or groove 50 Upper end hardware 53 Internal thread 54 Cylindrical wall 55 Inner surface (cylindrical surface)
56 Inner seat 58 Set bolt mounting hole 60 Set bolt 70 Clearance 71, 72, 73, 74 Point 100, 110 Steel pipe pile 101, 111 Weld joint 120 Joint part 121 Support part 122 Load point 123 Beam 124 Load 130 Lifting tool 131 Lifting 132 Floor

Claims

鋼管杭端にそれぞれ設けられ、雄ねじを有する雄側筒体と雌ねじを有する雌側筒体とからなり、ねじは平行ねじの３条以上の多条ねじとし、雄側筒体の先端に前記雌ねじ内径に遊嵌する外径を有する円筒部を設けたことを特徴とする鋼管杭の接合継手。Each of the steel pipe pile ends is provided with a male cylinder having a male thread and a female cylinder having a female thread. The screw is a multi-threaded thread having three or more parallel threads, and the female thread is formed at the tip of the male cylinder. A steel pipe pile joint, comprising a cylindrical portion having an outer diameter loosely fitted to the inner diameter.

前記円筒部に代わり、雌側筒体の先端に前記雄ねじの外径に遊嵌する内面円筒部を設けたことを特徴とする請求項１記載の鋼管杭の接合継手。The steel pipe pile joint according to claim 1, wherein an inner cylindrical portion that loosely fits to the outer diameter of the male screw is provided at the tip of the female cylinder instead of the cylindrical portion.

雌側筒体の先端に前記雄ねじの外径に遊嵌する内面円筒部を設けたことを特徴とする請求項１記載の鋼管杭の接合継手。The steel pipe pile joint according to claim 1, wherein an inner cylindrical portion that loosely fits to the outer diameter of the male screw is provided at the tip of the female cylinder.

前記円筒部の先端が当接する内周座を前記雌側筒体内面に設けたことを特徴とする請求項１又は３記載の鋼管杭の接合継手。The steel pipe pile joint according to claim 1 or 3, wherein an inner circumferential seat with which the tip of the cylindrical portion abuts is provided on the inner surface of the female side cylindrical body.

前記内面円筒部の先端が直接又は止水ゴムリングを介して当接する外周座を前記雄側筒体外面に設けたことを特徴とする請求項２、３又は４記載の鋼管杭の接合継手。The steel pipe pile joint according to claim 2, 3 or 4, wherein an outer peripheral seat with which the tip of the inner cylindrical portion abuts directly or via a water-stopping rubber ring is provided on the outer surface of the male cylinder.

前記円筒部の外周に凹溝又は凹孔を設け、該凹溝又は凹孔に嵌入するセットボルトの装着孔を前記雌側筒体に設けたことを特徴とする請求項１、３、４又は５記載の鋼管杭の接合継手。A concave groove or a concave hole is provided on the outer periphery of the cylindrical portion, and a mounting bolt mounting hole that fits into the concave groove or the concave hole is provided in the female cylinder. 5. A joint for steel pipe piles according to 5.

前記セットボルトの装着孔は筒体の中心点対称に１対設け、前記凹孔は筒体の中心点対称にＮ（Ｎは多条ねじの条数）対以上を円周上に等間隔に配置したことを特徴とする請求項６記載の鋼管杭の接合継手。 A pair of mounting holes for the set bolts are provided symmetrically with respect to the center of the cylinder, and the concave holes are symmetrical with respect to the central point of the cylinder, where N (N is the number of multiple threads) equal to or greater than the circumference on the circumference. bonding joint hands of the steel pipe pile according to claim 6, characterized in that the placed.