JP2004249643A

JP2004249643A - Fixing method of reinforcing bar, forming device of fixing part and reinforcing bar with fixing plate

Info

Publication number: JP2004249643A
Application number: JP2003043817A
Authority: JP
Inventors: Ichiro Fukuda; 一郎福田; Noboru Sakata; 昇坂田; Kosuke Furuichi; 耕輔古市
Original assignee: Kajima Corp
Current assignee: Kajima Corp
Priority date: 2003-02-21
Filing date: 2003-02-21
Publication date: 2004-09-09
Anticipated expiration: 2023-02-21
Also published as: JP4471256B2

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fixing method of a reinforcing bar, a forming device of a fixing part and the reinforcing bar with a fixing plate which enable an efficient construction even when the density of arranged reinforcing bars is high. <P>SOLUTION: The conductive fixing plate 3 which can be engaged with the arranged reinforcing bars 40, 41 is held by a plate engaging part 11 of pressing/detaching mechanisms 14 and 21, being opposed to the end part 2 of the reinforcing bar 1 inserted in the direction of intersecting the arranged reinforcing bars 40, 41, and the mechanisms 14 and 21 are retained for the reinforcing bar 1. A power source 26 is connected to the fixing plate 3 and the reinforcing bar 1, an arc is generated by adjusting a gap between the fixing plate 3 and the reinforcing bar 1 by the pressing/detaching mechanisms 14 and 21 and then the fixing plate 3 is pressed on the end part 2 of the reinforcing bar 1 and welded thereto. Thereby the reinforcing bar 1 is fixed to the arranged reinforcing bars 40, 41. Preferably, the surface of the fixing plate 3, being opposite to the reinforcing bar 1, is inclined for engagement with the arranged reinforcing bars 41, 42, or provided with projections 38, 39 for engagement with the bars 41, 42. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【０００１】
【発明の属する技術の分野】
本発明は補強鉄筋の定着方法及び定着部形成装置並びに定着プレート付き補強鉄筋に関し、とくに鉄筋コンクリート構造において配筋済鉄筋と交差する向きに補強鉄筋を定着する方法及び当該補強鉄筋に配筋済鉄筋への定着部を形成する装置並びに配筋済鉄筋へ定着する定着プレート付き補強鉄筋に関する。
【０００２】
【従来の技術】
鉄筋コンクリート構造では、コンクリート内に主筋（軸方向鉄筋）や配力筋（軸方向鉄筋と直角向きの鉄筋）を配筋すると共に、必要に応じて引張力や圧縮力に対する強度を増大するため主筋や配力筋と交差する向きにせん断補強鉄筋や帯鉄筋等（以下、これらを纏めて補強鉄筋という。）を配筋する必要がある。従来は、棒状の補強鉄筋の端部を鉤状、鋭角状又は半円形状に折り曲げ加工してフックを形成し、そのフックを主筋や配力筋へ係止することにより補強鉄筋を主筋や配力筋に定着している。しかし、折り曲げ加工は手間を要するだけでなく、フックの径を小さくすることが難しいため主筋や配力筋を含めて複雑な順序で組み立てる必要があり、とくに主筋や配力筋が密に配筋されている場合に補強鉄筋の施工が難しくなる問題点がある。そこで近年は、端部にプレートを固定した補強鉄筋を用いる方式が提案されている。
【０００３】
例えば特許文献１は、棒状鉄筋の端部に穴付き定着具をカプラ（ナット等）により固定するせん断補強構造を開示している。このせん断補強構造は、既に配筋されている格子状の主筋の間に棒状鉄筋を挿入し、その棒状鉄筋の端部に定着具を貫通させると共に定着具を隣接する主筋に係合させ、更にカプラを螺合させて定着具を固定することにより棒状鉄筋を主筋に定着するので、主筋が密に配筋されている場合でもせん断補強構造を効率良く構築できる。特許文献２及び３は、主筋の定着を目的として、ねじふし鉄筋とそれが螺合可能なねじ孔が形成された板状定着部とを用いる主筋の定着構造を開示している。
【０００４】
また特許文献４は、鉄筋の軸線方向の一部領域（例えば端部）を塑性変形容易な温度に加熱し、その加熱領域を軸線方向に圧縮して半径方向外方に塑性変形させる熱間据込加工により拡径部を形成した定着部付き鉄筋を開示する。熱間据込加工の際に適当な型を用いて拡径部の外周面の形状及び寸法を調整し、鉄筋の圧縮量の調節により拡径部を調整することができる。更に特許文献５及び非特許文献１は、図１０に示すように、摩擦圧接法により鋼棒１の端部に主筋４０、４１等に引っ掛けるための掛止板（定着プレート）３を固定したせん断補強筋を開示する。摩擦圧接法とは、鉄筋１と定着プレート３とを高速で相対的に回転させて押し付け、その時に発生する摩擦熱により両者を接合する方法である。
【０００５】
【特許文献１】特開平９−２２８５５０号公報
【特許文献２】特許第２６６２１５０号公報
【特許文献３】特許第２７８０６４５号公報
【特許文献４】特開２０００−２５７２０９号公報
【特許文献５】特開平１０−１９６１２０号公報
【非特許文献１】「プレート定着型剪断補強鉄筋Ｈｅａｄ−ｂａｒ技術資料」ＶＳＬジャパン株式会社、２００１年１０月
【０００６】
【発明が解決しようとする課題】
しかし、特許文献１の開示する方法はカプラ部分がコンクリート被り部分に大きくはみ出すため部材断面が合理的でなく、特許文献２の方法は使用する鉄筋が限られる等の問題点がある。また、これらの方法は、コンクリート打設時等に定着部が鉄筋から分離するおそれがあるため、鉄筋と定着部との間に樹脂等の充填材を注入して接着する必要が生じる場合があり、その場合には充填材の注入作業の手間とコストが必要となる。
【０００７】
これに対し、熱間据込加工や摩擦圧接法で鉄筋に定着プレートを固定する方法は、任意の鉄筋に適用可能であり、鉄筋と定着部とが分離し難い利点がある。例えば摩擦圧接工程では、鉄筋とプレートとの接合部に鉄筋母材以上の引張強度が保証されている（非特許文献１のｐｐ０９−１１参照）。また、同じ鉄筋径の半円形フックに比べて定着プレートの径をかなり小さくできる。例えば図１０に示すように、主筋４０、４１等の配筋状況や施工性に応じて定着プレート３を補強鉄筋１の片側又は両側に取り付け、配筋済の主筋４０、４１等の間に定着プレート３を挿入して回転することにより補強鉄筋１を定着することが可能である。
【０００８】
しかし、熱間据込加工や摩擦圧接法は事前に工場等で補強鉄筋に定着プレートを取り付けておく必要がある。定着プレートが取り付けられた補強鉄筋は、定着プレートを主筋等の間に挿入することができない程度に主筋等が高密度で配筋されていると、使用できない問題点がある。そのような場合は、従来のように配筋しながら折り曲げ加工してフックを形成する方法に依らざるを得ず、施工効率の向上が図れない。高密度に配筋された主筋等に対しても補強鉄筋を効率良く配筋できる技術の開発が望まれている。
【０００９】
そこで本発明の目的は、配筋済鉄筋が高密度である場合でも効率良く施工できる補強鉄筋の定着方法及び定着部形成装置を提供することにある。
【００１０】
【課題を解決するための手段】
図１及び２の実施例を参照するに、本発明による補強鉄筋の定着方法は、配筋済鉄筋４０、４１（図１０参照）と交差する補強鉄筋１を当該補強鉄筋１に固定の定着プレート３により現場定着する方法において、押圧・引き離し機構１４、２１のプレート係止部１１により導電性の定着プレート３を配筋済鉄筋４０、４１上に配置した補強鉄筋１の端部２に対向させて保持し、押圧・引き離し機構１４、２１を補強鉄筋１に対して拘束し、定着プレート３及び補強鉄筋１を溶接電源２６に接続し且つ押圧・引き離し機構１４、２１で定着プレート３と補強鉄筋１との間隙を調節することにより定着プレート３を補強鉄筋１の端部２へ溶接してなるものである。この溶接は、定着プレート３の配筋済鉄筋４０、４１への係止前又は係止後に行うことができる。
【００１１】
また、図１及び２のブロック図を参照するに、本発明による補強鉄筋の定着部形成装置１０は、鉄筋１の端部２を把持する把持部１２、鉄筋１の端部２に対向させて導電性の定着プレート３を保持するプレート係止部１１、係止部１１を把持部１２へ向かう所定軸線上で移動させる押圧機構１４と引き離し機構２１、及び把持部１２と係止部１１とに接続された溶接電源２６を備えてなるものである。
【００１２】
【実施の形態】
本発明の定着方法は、配筋済の主筋や配力筋、帯筋等の鉄筋４０、４１の間に補強鉄筋１の端部２を挿入し、その端部２に配筋済鉄筋４０、４１に係止可能な導電性定着プレート３を溶接することにより、補強鉄筋１を配筋済鉄筋４０、４１に定着するものである。この方法によれば、配筋済鉄筋４０、４１が高密度である場合でも補強鉄筋１を現場で効率良く配筋することが可能となる。本発明者は、補強鉄筋１の端部２に定着プレート３を溶接する方法として、鋼棒や黄銅棒等を板状の母材に植え付ける従来のスタッド溶接に注目した。但し、スタッド溶接は比較的小さい鋼棒等を比較的大きい母材に取り付ける方法であるのに対し、本発明の方法では平面状の定着プレート３を棒状の補強鉄筋１の端部２に取り付ける必要がある。
【００１３】
図１は、前記溶接に使用する本発明の定着部形成装置１０の一実施例を示す。図示例の定着部形成装置１０は可搬型のものであり、所定軸線（以下、溶接軸線ということがある。）上で移動する押圧機構１４及び引き離し機構２１と溶接電源２６とを有する。図示例の押圧機構１４は、拡径部１６を有するピストンロッド１５と、そのピストン拡径部１６が摺動可能に嵌合するシリンダ１７と、シリンダ１７を溶接軸線上で押圧向きに付勢するスプリング２０とを有する。シリンダ１７内のピストン拡径部１６の両側エア室Ｐ１、Ｐ２はそれぞれエア供給・排出路３１、３２に連通されており、エアの供給・排出によりシリンダ１７内のピストン拡径部１６の位置を調節できる。なお図中の符号１８は、ピストンロッド１５を摺動可能に保持するチャックアダプタを示す。また、図示例の引き離し機構２１は、シリンダ１７に固定の駆動体２２と、駆動体２２を溶接軸線上で離隔向きに駆動するソレノイド２３とを有する。ソレノイド２３による駆動体２２の移動量（引き離し量）を調節部３０で調節できる。但し、押圧機構１４及び引き離し機構２１の構成は図示例に限定されず、後述するプレート保持部１１を溶接軸線方向に駆動できるものであれば足りる。図示例の溶接電源１６は、ケーブル２７、２８により後述するプレート保持部１１及び把持部１２に接続され、アーク溶接に必要な溶接電流を供給するものである。
【００１４】
また図示例の定着部形成装置１０は、補強鉄筋１の端部２を把持する把持部１２と、その端部２に対向させて導電性の定着プレート３を所定姿勢で保持するプレート保持部１１とを有する。保持部１１は、例えばマグネットやテーパー状のチャックにより定着プレート３を脱離自在に係止すると共に、定着プレート３を溶接軸線上に位置決めする。図示例の保持部１１は押圧機構１４のピストンロッド１５の先端に設けた取り付け部１５ａに取り付けているが、保持部１１の取り付け位置は図示例に限定されない。例えば、チャックアダプタ１８の先端に設けたチャック１９をプレート保持部１１とするか、又は定着部形成装置１０の筐体２４に適当な腕部材（図示せず）等を設けてプレート定着部１１としてもよい。把持部１２は、補強鉄筋１の端部２を把持して溶接軸線上に位置決めすると共に、定着部形成装置１０を補強鉄筋１に対して拘束する。図示例の把持部１２は複数の腕部材を有し、補強鉄筋１の端部２を複数部位で挟持することにより安定的に位置決めできる。
【００１５】
図１の定着部形成装置１０を用いて補強鉄筋１を配筋済鉄筋４０、４１へ定着する場合は、先ず配筋済鉄筋４０、４１の間に交差向きに補強鉄筋１の棒状の端端２を挿入し、図１の定着部形成装置１０のプレート保持部１１に保持した定着プレート３を補強鉄筋１の軸線方向と交差させて挿入後の端部２に対向させる。このとき定着プレート３を配筋済鉄筋４０、４１へ係止してもよい。図示例では、定着プレート３のプレート保持部１１への取り付け容易化を図るため、取り付け時に押圧機構１４のシリンダ１７のエア室Ｐ１へエアを供給してプレート保持部１１を取り付け位置に後退させ、取り付け後にシリンダ１７のエア室Ｐ２へエアを供給してプレート保持部１１を作業位置に戻すことができる。作業位置のプレート保持部１１は、押圧機構１４のスプリング２０により押圧される。また図３（Ａ）に示すように、挿入後の補強鉄筋１の端部２にはフェルール（アークシールド）８を取り付ける。
【００１６】
次に、定着部形成装置１０の把持部１２で補強鉄筋１の端部２を把持することにより、補強鉄筋１の端部２と定着プレート３上の所定溶接部位とを溶接軸線上に位置付けると共に、定着プレート３の所定溶接部位と補強鉄筋１の端部２とを当接させる。図示例では溶接電源１６がプレート保持部１１及び把持部１２に接続されているので、この当接した状態でスイッチ３３を閉路して補強鉄筋１と定着プレート３との間に電流を流し、電流を流しながら引き離し手段２１のソレノイド２３を励起することにより定着プレート３を補強鉄筋１の端部２から少し引き離してアークを発生させ、少なくとも定着プレート３の一部を適当に溶融することができる。その後、引き離し手段２１のソレノイド２３の励起を解除してスプリング１２の弾性により定着プレート３の溶融池を補強鉄筋１の端部２へ押圧することにより、定着プレート３を補強鉄筋１へ溶接する。必要に応じて図３（Ｃ）に示すように、補強鉄筋１の端部２をアーク溶接用の被覆剤で被覆し、又はアーク溶接が可能な材料で被覆してもよい。
【００１７】
本発明の定着方法は、図１（Ｂ）に示すように補強鉄筋１の両端に定着プレート３を取り付ける場合、及び同図（Ｃ）のように補強鉄筋１の一端に定着プレート３を取り付け場合の何れにも使用できる。図１の実施例では、把持部１２で補強鉄筋１の端部２を把持することにより定着部形成装置１０を補強鉄筋１に対して拘束しているが、補強鉄筋１がコンクリート型枠３５と交差する向きである場合は、図２に示すように補強鉄筋１の溶接端２の反対側端とコンクリート型枠３５との間にスペーサ３６を挿入することにより定着部形成装置１０を補強鉄筋１に対して拘束することができる。このようにスペーサ３６によって補強鉄筋１を拘束できる場合は、定着部形成装置１０から把持部１２を省略できる。
【００１８】
図３（Ａ）の実施例では補強鉄筋１の端部２にフェルール８を取り付けているが、同図（Ｄ）に示すように定着プレート３上の補強鉄筋１との対向部位に補強鉄筋１の端部２と実質上同径の棒状突起６を設け、その突起６の先端にフェルール８を装着してもよい。このような棒状突起６は従来のスタット溶接技術により定着プレート３へ植え付けることができ、定着プレート３側にフェルール８を装着すれば補強鉄筋１にフェルール８を装着する手間を省くことができる。また同図（Ｂ）のように、定着プレート３上の補強鉄筋１との対向部位に補強鉄筋１の端部２と実質上同径の窪み５を設け、その窪み５にフェルール８を装着することも考えられる。定着プレート３の窪み５にフェルール８を装着することにより、フェルール８の脱落防止が期待できる。
【００１９】
更に本発明では、図４に示すように、補強鉄筋１と定着プレート３とのアーク溶接時にフェルールを省略することも期待できる。同図の例では、定着プレート３上の補強鉄筋１との対向部位に開口端が補強鉄筋１の端部２と実質上同径で底壁５ａへ向かうに従い内径が徐々に拡径する窪み５を穿ち（同図（Ａ）参照）、窪み５の内周壁に開口から底壁５ａへ至る深さ方向の１以上の溝（以下、スリットということがある。）５ｂを設けている（同図（Ｂ）参照）。好ましくは放射状に設けた複数のスリット５ｂから窪み５の内部のアーク熱で高圧化した内部ガスを逸出させることにより、窪み５を実質上フェルールと同様に機能させ、フェルールなしでのアーク溶接が期待できる。フェルールを省略することにより、アーク溶接後のフェルール回収の手間を省き施工の簡単化が図れる。
【００２０】
本発明の定着方法では、定着プレート３を配筋済鉄筋４０、４１へ係止させた後に補強鉄筋１の端部２に溶接することが可能であるが、主筋４０、４１等の配筋状況や施工性に応じて定着プレート３を補強鉄筋１の端部２に溶接した後に配筋済鉄筋４０、４１へ係止してもよい。溶接後に配筋済鉄筋４０、４１へ係止する場合は、図６に示すように、先ず補強鉄筋１の一端を配筋済鉄筋４１へ係止し、その係止部の回りに補強鉄筋１を矢印Ｒの向きに回転させることにより他端に溶接した定着プレート３を配筋済鉄筋４０へ係止することができる。
【００２１】
本発明によれば、配筋済鉄筋４０、４１の間に補強鉄筋１を挿入・配置した後に定着プレート３を挿入後の補強鉄筋１の端部２に取り付け得るので、定着プレート３を通過させることができない程度に配筋済鉄筋４０、４１が高密度で配筋されている場合にも適用できる。また、現場で定着プレート３を取り付けることができるので、多少の配筋の変動に対しても容易に対応可能であり、所定の補強効果が確保できる。従って、高密度で鉄筋を配筋する鉄筋コンクリート施工現場において、補強鉄筋１を高効率で配筋することが可能であり、配筋作業の単純化及び省力化を図り、工期の短縮及びコストダウンへの寄与が期待できる。
【００２２】
こうして本発明の目的である「配筋済鉄筋が高密度である場合でも効率良く施工できる補強鉄筋の定着方法及び定着部形成装置」を達成することができる。
【００２３】
【実施例】
図５は、本発明で用いる定着プレート３付き補強鉄筋１の一実施例を示す。この実施例では、補強鉄筋１との対向面に補強鉄筋１との対向部位から配筋済鉄筋４０、４１への係止部位まで徐々に配筋済鉄筋４０、４１へ向かう勾配を設けた定着プレート３を用いている。図１０に示す従来の方法では、補強鉄筋１を定着プレート３の法線方向（垂直方向）に取り付けているので、例えば定着プレート３の表面に被せたコンクリート（被りコンクリート）が剥離した場合等に定着プレート３の配筋済鉄筋４０、４１に対する係止が緩む方向に力が作用し、補強鉄筋１の定着効果が低減する可能性があった。同図（Ａ）に示すように、定着プレート３を補強鉄筋１との固定部位から配筋済鉄筋４０との係止部位へ向けて傾斜させることにより、定着プレート３を力学的に安定した形とし、地震等によって被りコンクリートが剥離した場合でも充分な補強効果が期待できる。
【００２４】
アーク溶接によれば、熱間据込加工や摩擦圧接法に比し補強鉄筋１に対する定着プレート３の取り付け角度の調節が容易であるので、図５（Ａ）のような傾斜角度で定着プレート３を補強鉄筋１に取り付けることが容易に可能である。定着プレート３を傾斜させるため、配筋済鉄筋４０、４１に対する補強鉄筋１の長さを調節してもよい。また、定着プレート３の補強鉄筋１との対向面の全体に勾配を設けるのではなく、同図（Ｂ）のように対向面に勾配部位と共に補強鉄筋１に対し垂直な部位を設けてもよい。
【００２５】
図５（Ｃ）及び（Ｄ）に示すように、配筋済鉄筋４０、４１へ向かう勾配は定着プレート３の補強鉄筋１との対向面に設ければ足り、定着プレート３の反対側面は任意の形状とすることができる。従って、定着プレート３に勾配を設けた場合でも、図１に示すプレート保持部１１への定着プレート３の保持姿勢は勾配に拘わらず一定とすることが可能である。更に施工上の観点から、同図（Ｅ）及び（Ｆ）に示すように、定着プレート３の配筋済鉄筋４０、４１への係止部位の外側（自由端側）に逆テーパー状の切欠きを設け、定着プレート３をできる限りコンパクトな形状とすることが望ましい。更に同図（Ｇ）に示すように直線状の勾配に代えて曲線状の勾配を設け、または複数の直線や任意の曲線を組み合わせた勾配を設けた場合でも同様の効果を得ることができる。
【００２６】
また、図５のように勾配を設けた定着プレート３は、補強効果の増大だけでなく、施工時に補強鉄筋１の位置決めを容易にするので施工性の改善・向上を図ることができる。補強鉄筋１を定着プレートと垂直に取り付ける従来方法では、定着プレート３と配筋済鉄筋４０、４１との間に効果的な係合がないため補強鉄筋１の位置ずれや脱落のおそれがあり、補強鉄筋１を配筋すると同時に結束線等によりその位置を固定する必要があった。勾配を設けた定着プレート３によれば、補強鉄筋１の配筋と同時に位置決めが可能となり、結束線等がなくとも補強鉄筋１を安定させることができる。結束線等を省略できれば、補強鉄筋１の定着作業の効率を格段に向上できる。
【００２７】
このような補強鉄筋１の位置決め容易化の観点からは、図５に示す勾配に代えて又は加えて、図７に示すように定着プレート３上の配筋済鉄筋４０、４１への係止部位に配筋済鉄筋４０、４１との係合突起３８を設けてもよい。同図（Ａ）は配筋済鉄筋４０から見て補強鉄筋１と反対側に設けたストッパー状の係合突起３８ａ、同図（Ｂ）は半球状の係合突起３８ｂ、同図（Ｃ）は流線型翼形状の係合突起３８ｃを示す。また同図（Ｄ）は、定着プレート３上に設けた多数の凹凸を係合突起３９とした実施例を示す。
【００２８】
図５及び図７に示す定着プレート３付き補強鉄筋１は、上述したアーク溶接によって形成できるが、従来の熱間据込加工や摩擦圧接法によって形成することも可能である。例えば、勾配付き又は係合突起３８付き定着プレート３を熱間据込加工や摩擦圧接法により補強鉄筋１の一端へ形成し又は取り付け、図６に示すような補強鉄筋１の回転により勾配付き又は係合突起３８付きの定着プレート３を配筋済鉄筋４０へ係止することにより、結束線の省略による作業効率の向上や補強効果の増大を図ることができる。この場合において図７（Ａ）及び（Ｄ）に示すように係合突起３８ａ、３８ｄの形状を、係止させる向き（図６の矢印Ｒの向き）の傾斜が緩やかで反対向きの傾斜を急峻とすることにより、係合し易く且つ離脱し難い係合突起３８とすることができる。
【００２９】
図８及び図９は、本発明で用いる定着プレート３付き補強鉄筋１の他の一例を示す。図８は、配筋済鉄筋４０、４１への係止部位の幅ｄ２が補強鉄筋１への固定部位の幅ｄ１に比し、その固定部位からの距離に応じて縮小された定着プレート３を用いたものである。例えばアーク溶接によれば補強鉄筋１と定着プレート３とを所要の引張強度以上に強固に接合することができるので、従来の半円形フックに比し定着プレート３を小さくすることが可能であるが、図８のようにモーメント分布に応じて定着プレート３の不要な部分をなくして形状を調整することにより、定着プレート３の更なるコンパクト化が可能となる。定着プレート３をコンパクトな最適形状とすることにより、補強鉄筋１のいわばヘッド部分が軽くなるので施工性の更なる向上が期待でき、また材料減少により製造コストの削減に寄与できる。
【００３０】
図８において、定着プレート３の配筋済鉄筋４０、４１への係止部位の幅ｄ２は、配筋済鉄筋４０、４１から定着プレート３に加わるモーメント分布に応じて定めることができる。例えば、補強鉄筋１への固定部位から配筋済鉄筋４０、４１への係止部位までの距離が長い場合、又は配筋済鉄筋４０、４１の寸法が太い場合はモーメントが大きくなる。従って、補強鉄筋１への固定部位からの距離及び／又は配筋済鉄筋４０、４１の寸法に応じて、同図（Ａ）〜（Ｄ）のように係止部位の幅ｄ２を設計できる。同図（Ｅ）のように、角部を曲線状とすることも可能である。
【００３１】
図９（Ａ）及び（Ｂ）は、定着プレート３の幅ｄの最適化に加えて又は代えて、配筋済鉄筋４０、４１への係止部位における定着プレート３の厚さを補強鉄筋１への固定部位の厚さに比し固定部位からの距離に応じて減少した実施例を示す（同図（Ｃ）参照）。モーメント分布に応じて定着プレート３の厚さを調整することにより、定着プレート３の更なるコンパクト化が可能となり、施工性の更なる向上が期待できる。この場合も、配筋済鉄筋４０、４１から定着プレート３に加わるモーメント分布に応じて、定着プレート３の配筋済鉄筋４０、４１への係止部位の厚さを定めることができる。
【００３２】
図８及び図９に示す定着プレート３の形状は、アーク溶接により補強鉄筋１と結合する場合だけでなく、従来の熱間据込加工や摩擦圧接法によって定着部を形成する場合にも有効に利用できる。定着プレート３のコンパクト化は、熱間据込加工や摩擦圧接法により定着部を形成する場合にも施工性の向上や製造コストの削減に寄与できる。
【００３３】
【発明の効果】
以上詳細に説明したように、本発明による補強鉄筋の定着方法及び定着部形成装置は、配筋済鉄筋上に配置した補強鉄筋の端部に対向させて導電性の定着プレートを押圧・引き離し機構のプレート保持部により保持し、押圧・引き離し機構を補強鉄筋に対して拘束し、定着プレート及び補強鉄筋を溶接電源に接続し且つ押圧・引き離し機構で定着プレートと補強鉄筋との間隙を増減することにより定着プレートを補強鉄筋の端部へ溶接するので、次の顕著な効果を奏する。
【００３４】
（イ）配筋済鉄筋の間に補強鉄筋を配置した後に定着プレートをセットすることができるので、配筋済鉄筋が高密度であっても補強鉄筋を効率良く定着できる。
（ロ）現場で施工可能であるため、多少の配筋の変動に対しても対応可能であり、所定の補強効果が確保できる。
（ハ）補強鉄筋の配筋作業の単純化及び省力化を図り、工期の短縮及びコストダウンへの寄与が期待できる。
（ニ）溶接により定着プレートと補強鉄筋とを結合することができるので、補強鉄筋に対する定着プレートの取り付け角度の調節が容易である。
【００３５】
（ホ）勾配付き定着プレートを用いることにより、定着プレートを配筋済鉄筋から脱落し難くし、コンクリートが剥落した場合でも補強効果の維持が期待できる。
（ヘ）勾配付き定着プレートを用いることにより、地震時等における主鉄筋の座屈抑止、構造物の靭性向上等の効果も期待できる。
（ト）従来の半円形フックに比し定着プレートの径を小さくすることが可能である。
（チ）モーメント分布に応じて定着プレートの形状や厚さを調整することにより、定着プレートを更にコンパクトで最適な形状とすることができる。
（リ）現場で定着プレートと補強鉄筋とを溶接することができるので、従来のプレート付き鉄筋に比し、輸送時における作業性、輸送効率の向上が期待できる。
【図面の簡単な説明】
【図１】は、本発明装置の一実施例の説明図である。
【図２】は、本発明装置の他の実施例の説明図である。
【図３】は、補強鉄筋と定着プレートとの溶接方法の一例の説明図である。
【図４】は、補強鉄筋と定着プレートとの溶接方法の他の一例の説明図である。
【図５】は、定着プレートの補強鉄筋との対向面の勾配の説明図である。
【図６】は、定着プレートを溶接した補強鉄筋の配筋済鉄筋への定着方法の一例の説明図である。
【図７】は、定着プレートに設けた配筋済鉄筋への係合突起の説明図である。
【図８】は、定着プレートの形状の一例の説明図である。
【図９】は、定着プレートの形状の他の一例の説明図である。
【図１０】は、従来の補強鉄筋の配筋済鉄筋への定着方法の説明図である。
【符号の説明】
１…補強鉄筋２…端部
３…定着プレート４…対向面
５…窪み５ａ…底壁
５ｂ…溝（スリット）６…棒状突起
７…被覆剤８…フェルール
９…反対側面１０…定着部形成装置
１１…保持部１２…把持部
１３…反対側端１４…押圧機構
１５…ピストンロッド１５ａ…取り付け部
１６…ピストン拡径部
１７…シリンダ１８…チャックアダプタ
１９…チャック２０…スプリング
２１…引き離し機構２２…駆動体
２３…ソレノイド２４…筐体
２５…ハンドル２６…溶接電源
２７…ケーブル２８…ケーブル
２９…ケーブル３０…調節部
３１…エア供給・排出路３２…エア供給・排出路
３３…スイッチ
３５…型枠３６…スペーサ
３８…係合突起３９…係合突起
４０…配筋済鉄筋４１…配筋済鉄筋[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a fixing method of a reinforcing bar, a fixing section forming apparatus, and a reinforcing bar with a fixing plate, and particularly to a method of fixing a reinforcing bar in a direction crossing a reinforcing bar in a reinforced concrete structure, and to a reinforcing bar provided to the reinforcing bar. The present invention relates to a device for forming a fixing portion of the present invention, and a reinforcing reinforcing bar with a fixing plate for fixing to a reinforcing bar.
[0002]
[Prior art]
In a reinforced concrete structure, main reinforcing bars (axial reinforcing bars) and force bars (rebars perpendicular to the axial reinforcing bars) are arranged in the concrete, and if necessary, the main reinforcing bars and the reinforcing bars are used to increase the strength against tensile and compressive forces. It is necessary to arrange shear reinforcing bars, band reinforcing bars, and the like (hereinafter collectively referred to as reinforcing bars) in a direction intersecting with the distribution bars. Conventionally, the end of a bar-shaped reinforcing bar is bent into a hook, an acute angle, or a semicircle to form a hook, and the hook is locked to a main bar or a distribution bar to connect the reinforcing bar to the main bar or the distribution bar. Established in the muscle. However, the bending process is not only time-consuming, but it is difficult to reduce the diameter of the hook, so it is necessary to assemble it in a complicated order including the main bars and the force bars. When it is done, there is a problem that the construction of the reinforcing bar becomes difficult. Therefore, in recent years, a method using a reinforcing reinforcing bar having a plate fixed to an end has been proposed.
[0003]
For example, Patent Literature 1 discloses a shear reinforcement structure in which a fixing tool with a hole is fixed to an end of a bar-shaped rebar by a coupler (such as a nut). In this shear reinforcement structure, a bar-shaped reinforcing bar is inserted between lattice-shaped main bars already arranged, a fixing device is penetrated through an end of the bar-shaped reinforcing bar, and the fixing device is engaged with an adjacent main bar. Since the bar-shaped rebar is fixed to the main bar by screwing the coupler and fixing the fixing device, the shear reinforcement structure can be efficiently constructed even when the main bar is densely arranged. Patent Literatures 2 and 3 disclose a main reinforcement fixing structure using a screw bar and a plate-shaped fixing portion having a screw hole to which the screw reinforcement can be screwed for the purpose of fixing the main reinforcement.
[0004]
Further, Patent Document 4 discloses a hot mounting method in which a region (for example, an end portion) in the axial direction of a reinforcing bar is heated to a temperature at which plastic deformation is easily performed, and the heated region is compressed in the axial direction to plastically deform radially outward. Disclosed is a reinforcing-bar with a fixing portion having an enlarged-diameter portion formed by engraving. At the time of hot upsetting, the shape and dimensions of the outer peripheral surface of the enlarged diameter portion are adjusted using an appropriate mold, and the enlarged diameter portion can be adjusted by adjusting the amount of compression of the reinforcing bar. Further, as shown in FIG. 10, Patent Document 5 and Non-Patent Document 1 disclose a shearing plate in which a locking plate (fixing plate) 3 for hooking the main bars 40, 41 and the like is fixed to the end of the steel rod 1 by friction welding. A reinforcement is disclosed. The friction welding method is a method in which the rebar 1 and the fixing plate 3 are relatively rotated at a high speed and pressed, and the two are joined by frictional heat generated at that time.
[0005]
[Patent Document 1] JP-A-9-228550
[Patent Document 2] Japanese Patent No. 2662150
[Patent Document 3] Japanese Patent No. 2780645
[Patent Document 4] JP-A-2000-257209
[Patent Document 5] JP-A-10-196120
[Non-patent document 1] "Plate-fixed type shear reinforcement reinforcing bar Head-bar technical data" VSL Japan Co., Ltd., October 2001
[0006]
[Problems to be solved by the invention]
However, the method disclosed in Patent Literature 1 has a problem that the coupler section largely protrudes into the concrete covering portion, so that the section of the member is not rational. In addition, in these methods, there is a possibility that the fixing portion may be separated from the reinforcing bar at the time of placing concrete, for example, so that it may be necessary to inject a filler such as a resin between the reinforcing bar and the fixing portion and bond them. In that case, labor and cost for the work of injecting the filler are required.
[0007]
On the other hand, the method of fixing the fixing plate to the reinforcing bar by hot upsetting or friction welding can be applied to any reinforcing bar, and has an advantage that the reinforcing bar and the fixing portion are hardly separated. For example, in the friction welding process, the joint between the reinforcing bar and the plate is guaranteed to have a tensile strength equal to or higher than the reinforcing bar base material (see pp09-11 in Non-Patent Document 1). Further, the diameter of the fixing plate can be considerably reduced as compared with a semicircular hook having the same rebar diameter. For example, as shown in FIG. 10, the fixing plate 3 is attached to one or both sides of the reinforcing steel bar 1 depending on the arrangement of the reinforcing bars 40, 41 and the like and the workability, and is fixed between the reinforcing bars 40, 41, and the like. The reinforcing bar 1 can be fixed by inserting and rotating the plate 3.
[0008]
However, the hot upsetting process and the friction welding method require a fixing plate to be attached to a reinforcing steel bar at a factory or the like in advance. The reinforcing reinforcing bar to which the fixing plate is attached cannot be used if the main reinforcing bars and the like are arranged at a high density so that the fixing plate cannot be inserted between the main reinforcing bars and the like. In such a case, there is no choice but to rely on a method of forming a hook by bending while arranging the bars as in the related art, and it is not possible to improve the construction efficiency. There is a demand for the development of technology that can efficiently arrange reinforcing reinforcing bars even for high-strength main reinforcing bars and the like.
[0009]
Therefore, an object of the present invention is to provide a fixing method of a reinforcing reinforcing bar and a fixing section forming apparatus which can be efficiently installed even when the reinforcing bars have a high density.
[0010]
[Means for Solving the Problems]
Referring to the embodiment of FIGS. 1 and 2, the fixing method of the reinforcing bar according to the present invention is a fixing plate for fixing the reinforcing bar 1 intersecting with the reinforced bars 40 and 41 (see FIG. 10) to the reinforcing bar 1. 3, the conductive fixing plate 3 is opposed to the end 2 of the reinforcing bar 1 disposed on the reinforced bars 40, 41 by the plate locking portions 11 of the pressing / pulling-off mechanisms 14, 21. The fixing plate 3 and the reinforcing bar 1 are connected to a welding power source 26, and the fixing plate 3 and the reinforcing bar are connected by the pressing / separating mechanisms 14, 21. The fixing plate 3 is welded to the end 2 of the reinforcing steel bar 1 by adjusting the gap with the fixing bar 1. This welding can be performed before or after the fixing plate 3 is locked to the reinforcing bars 40, 41.
[0011]
Referring to the block diagrams of FIGS. 1 and 2, a fixing unit forming apparatus 10 of a reinforcing bar according to the present invention includes a gripping unit 12 that grips an end 2 of a reinforcing bar 1 and an end 2 of the reinforcing bar 1. The plate locking portion 11 for holding the conductive fixing plate 3, the pressing mechanism 14 for moving the locking portion 11 on a predetermined axis toward the grip portion 12, the separation mechanism 21, and the grip portion 12 and the locking portion 11 It comprises a connected welding power source 26.
[0012]
Embodiment
According to the fixing method of the present invention, the end 2 of the reinforcing bar 1 is inserted between the reinforcing bars 40, 41 such as a main bar, a force bar, a band bar, etc., and the reinforcing bar 40, The reinforcing reinforcing bar 1 is fixed to the reinforcing bars 40 and 41 by welding the conductive fixing plate 3 that can be locked to the reinforcing bar 41. According to this method, the reinforcing reinforcing bar 1 can be efficiently disposed on site even when the reinforcing bars 40 and 41 have a high density. As a method of welding the fixing plate 3 to the end 2 of the reinforcing steel bar 1, the present inventor paid attention to conventional stud welding in which a steel bar, a brass bar, or the like is planted in a plate-shaped base material. However, while the stud welding is a method of attaching a relatively small steel bar or the like to a relatively large base material, the method of the present invention requires attaching a flat fixing plate 3 to the end 2 of the bar-shaped reinforcing bar 1. There is.
[0013]
FIG. 1 shows an embodiment of the fixing portion forming apparatus 10 of the present invention used for the welding. The illustrated fixing unit forming apparatus 10 is a portable type, and includes a pressing mechanism 14 that moves on a predetermined axis (hereinafter, sometimes referred to as a welding axis), a separating mechanism 21, and a welding power source 26. The pressing mechanism 14 in the illustrated example has a piston rod 15 having an enlarged diameter portion 16, a cylinder 17 into which the piston enlarged diameter portion 16 is slidably fitted, and biases the cylinder 17 in a pressing direction on a welding axis. And a spring 20. The air chambers P1 and P2 on both sides of the piston enlarged portion 16 in the cylinder 17 are connected to air supply / discharge passages 31 and 32, respectively, and the position of the piston enlarged portion 16 in the cylinder 17 is changed by the supply and discharge of air. Can be adjusted. Reference numeral 18 in the drawing indicates a chuck adapter that slidably holds the piston rod 15. Further, the separation mechanism 21 in the illustrated example has a driving body 22 fixed to the cylinder 17 and a solenoid 23 for driving the driving body 22 in the direction away from the welding axis. The amount of movement (separation amount) of the driving body 22 by the solenoid 23 can be adjusted by the adjusting unit 30. However, the configuration of the pressing mechanism 14 and the separating mechanism 21 is not limited to the illustrated example, and any structure that can drive a plate holding unit 11 described later in the welding axis direction is sufficient. The welding power supply 16 in the illustrated example is connected to a plate holding section 11 and a grip section 12 described later by cables 27 and 28, and supplies a welding current necessary for arc welding.
[0014]
The illustrated fixing unit forming apparatus 10 includes a holding unit 12 that holds the end 2 of the reinforcing bar 1, and a plate holding unit 11 that holds the conductive fixing plate 3 in a predetermined posture facing the end 2. And The holding section 11 detachably locks the fixing plate 3 by, for example, a magnet or a tapered chuck, and positions the fixing plate 3 on the welding axis. The holding portion 11 in the illustrated example is attached to an attachment portion 15a provided at the tip of the piston rod 15 of the pressing mechanism 14, but the attachment position of the holding portion 11 is not limited to the illustrated example. For example, the chuck 19 provided at the tip of the chuck adapter 18 is used as the plate holding unit 11, or an appropriate arm member (not shown) or the like is provided on the housing 24 of the fixing unit forming apparatus 10 to form the plate fixing unit 11. Is also good. The gripper 12 grips the end 2 of the reinforcing bar 1 and positions it on the welding axis, and restrains the fixing unit forming device 10 with respect to the reinforcing bar 1. The grip portion 12 in the illustrated example has a plurality of arm members, and can stably position by holding the end 2 of the reinforcing steel bar 1 at a plurality of portions.
[0015]
When fixing the reinforcing bar 1 to the reinforcing bars 40 and 41 using the fixing unit forming apparatus 10 of FIG. 1, first, the bar-shaped end of the reinforcing bar 1 crosswisely interposed between the reinforcing bars 40 and 41. 2 is inserted, and the fixing plate 3 held by the plate holding unit 11 of the fixing unit forming apparatus 10 in FIG. 1 is made to intersect the axial direction of the reinforcing bar 1 and to face the inserted end 2. At this time, the fixing plate 3 may be locked to the reinforcing bars 40, 41. In the illustrated example, in order to facilitate attachment of the fixing plate 3 to the plate holding portion 11, air is supplied to the air chamber P <b> 1 of the cylinder 17 of the pressing mechanism 14 at the time of attachment, and the plate holding portion 11 is retracted to the attachment position. After the mounting, air can be supplied to the air chamber P2 of the cylinder 17 to return the plate holding portion 11 to the working position. The plate holding part 11 at the working position is pressed by the spring 20 of the pressing mechanism 14. Further, as shown in FIG. 3A, a ferrule (arc shield) 8 is attached to the end 2 of the reinforcing reinforcing bar 1 after insertion.
[0016]
Next, by gripping the end 2 of the reinforcing bar 1 with the holding unit 12 of the fixing unit forming device 10, the end 2 of the reinforcing bar 1 and a predetermined welding portion on the fixing plate 3 are positioned on the welding axis. Then, the predetermined welding portion of the fixing plate 3 is brought into contact with the end 2 of the reinforcing steel bar 1. In the illustrated example, since the welding power source 16 is connected to the plate holding portion 11 and the holding portion 12, the switch 33 is closed in this abutting state, and a current flows between the reinforcing reinforcing bar 1 and the fixing plate 3, and When the solenoid 23 of the separating means 21 is excited while flowing, the fixing plate 3 is slightly separated from the end 2 of the reinforcing steel bar 1 to generate an arc, and at least a part of the fixing plate 3 can be appropriately melted. After that, the excitation of the solenoid 23 of the separating means 21 is released, and the molten pool of the fixing plate 3 is pressed against the end 2 of the reinforcing bar 1 by the elasticity of the spring 12, thereby welding the fixing plate 3 to the reinforcing bar 1. If necessary, as shown in FIG. 3C, the end 2 of the reinforcing steel bar 1 may be coated with a coating agent for arc welding or a material capable of arc welding.
[0017]
The fixing method according to the present invention includes a case where the fixing plates 3 are attached to both ends of the reinforcing bar 1 as shown in FIG. 1B and a case where the fixing plate 3 is attached to one end of the reinforcing bar 1 as shown in FIG. It can be used for any of In the embodiment of FIG. 1, the fixing portion forming device 10 is restrained with respect to the reinforcing steel bar 1 by gripping the end 2 of the reinforcing steel bar 1 with the gripping portion 12. In the case of the intersecting direction, as shown in FIG. 2, a spacer 36 is inserted between the opposite end of the reinforcing bar 1 on the opposite side of the welded end 2 and the concrete formwork 35 so that the fixing part forming apparatus 10 is connected to the reinforcing bar 1. Can be restrained. When the reinforcing reinforcing bar 1 can be restrained by the spacer 36 as described above, the gripping portion 12 can be omitted from the fixing portion forming device 10.
[0018]
In the embodiment shown in FIG. 3A, the ferrule 8 is attached to the end portion 2 of the reinforcing bar 1, but as shown in FIG. May be provided with a rod-shaped projection 6 having substantially the same diameter as the end 2 of the base member, and a ferrule 8 may be attached to the tip of the projection 6. Such a rod-shaped projection 6 can be planted on the fixing plate 3 by a conventional stat welding technique, and if the ferrule 8 is mounted on the fixing plate 3 side, the labor for mounting the ferrule 8 on the reinforcing reinforcing bar 1 can be saved. Also, as shown in FIG. 2B, a recess 5 having substantially the same diameter as the end 2 of the reinforcing bar 1 is provided at a position on the fixing plate 3 facing the reinforcing bar 1, and a ferrule 8 is mounted in the recess 5. It is also possible. By mounting the ferrule 8 in the recess 5 of the fixing plate 3, it can be expected that the ferrule 8 will be prevented from falling off.
[0019]
Further, in the present invention, as shown in FIG. 4, it is expected that the ferrule may be omitted when the reinforcing reinforcing bar 1 and the fixing plate 3 are arc welded. In the example shown in the figure, a recess 5 whose opening end is substantially the same diameter as the end portion 2 of the reinforcing bar 1 and has an inner diameter gradually increasing toward the bottom wall 5 a at a position facing the reinforcing bar 1 on the fixing plate 3. (See FIG. 2A), and one or more grooves (hereinafter, sometimes referred to as slits) 5b in the depth direction from the opening to the bottom wall 5a are provided on the inner peripheral wall of the depression 5 (FIG. 2A). (B)). Preferably, the internal gas pressurized by the arc heat inside the depression 5 is released from the plurality of slits 5b provided radially, so that the depression 5 functions substantially as a ferrule, and arc welding without a ferrule is performed. Can be expected. By omitting the ferrule, the work of collecting the ferrule after arc welding can be omitted and the construction can be simplified.
[0020]
In the fixing method of the present invention, it is possible to lock the fixing plate 3 to the reinforcing bars 40 and 41 and then weld the fixing plate 3 to the end 2 of the reinforcing bar 1. Depending on the workability, the fixing plate 3 may be welded to the end 2 of the reinforcing bar 1 and then locked to the reinforced bars 40 and 41. In order to lock the reinforcing bars 40 and 41 after welding, first, as shown in FIG. 6, one end of the reinforcing bar 1 is locked to the reinforcing bar 41, and the reinforcing bars 1 around the locking portion. By rotating the fixing plate 3 in the direction of the arrow R, the fixing plate 3 welded to the other end can be locked to the reinforced reinforcing bars 40.
[0021]
According to the present invention, the fixing plate 3 can be attached to the end 2 of the reinforcing bar 1 after insertion after the reinforcing bar 1 is inserted and arranged between the reinforcing bars 40 and 41, so that the fixing plate 3 is passed through. The present invention can also be applied to a case where the reinforcing bars 40 and 41 are arranged at a high density to the extent that they cannot be performed. Further, since the fixing plate 3 can be attached on site, it is possible to easily cope with a slight variation in the arrangement of reinforcing bars, and a predetermined reinforcing effect can be secured. Therefore, in a reinforced concrete construction site in which reinforcing bars are arranged at a high density, it is possible to arrange reinforcing bars 1 with high efficiency, and to simplify and reduce labor for reinforcing work, shortening the construction period and reducing costs. Can be expected to contribute.
[0022]
Thus, the object of the present invention can be achieved "the fixing method and the fixing portion forming apparatus of the reinforcing reinforcing bar which can be efficiently constructed even when the reinforcing bars are high in density".
[0023]
【Example】
FIG. 5 shows an embodiment of the reinforcing bar 1 with the fixing plate 3 used in the present invention. In this embodiment, a fixing is provided on the surface facing the reinforcing bar 1 from the portion facing the reinforcing bar 1 to the portion where the reinforcing bars 40 and 41 are locked, and gradually slopes toward the reinforcing bars 40 and 41. Plate 3 is used. In the conventional method shown in FIG. 10, the reinforcing reinforcing bar 1 is attached in the normal direction (vertical direction) of the fixing plate 3, and thus, for example, when the concrete (covering concrete) covering the surface of the fixing plate 3 is peeled off. There is a possibility that a force acts in a direction in which the fixing of the fixing plate 3 to the reinforcing bars 40 and 41 is loosened, and the fixing effect of the reinforcing bar 1 is reduced. As shown in FIG. 2A, the fixing plate 3 is inclined from the portion where the reinforcing plate 1 is fixed to the reinforcing bar 1 to the position where the fixing plate 3 is locked with the reinforcing bar 40, so that the fixing plate 3 has a mechanically stable shape. A sufficient reinforcing effect can be expected even when the concrete comes off due to an earthquake or the like.
[0024]
According to the arc welding, the fixing angle of the fixing plate 3 with respect to the reinforcing steel bar 1 can be easily adjusted as compared with the hot upsetting process and the friction welding method, so that the fixing plate 3 is inclined at an inclination angle as shown in FIG. Can be easily attached to the reinforcing steel bar 1. In order to incline the fixing plate 3, the length of the reinforcing reinforcing bar 1 with respect to the reinforcing bars 40 and 41 may be adjusted. Also, instead of providing a gradient on the entire surface of the fixing plate 3 facing the reinforcing bar 1, a portion perpendicular to the reinforcing bar 1 may be provided along with the gradient portion on the facing surface as shown in FIG. .
[0025]
As shown in FIGS. 5 (C) and 5 (D), the gradient toward the reinforced reinforcing bars 40, 41 only needs to be provided on the surface of the fixing plate 3 facing the reinforcing bar 1, and the opposite side of the fixing plate 3 is optional. Shape. Therefore, even when the fixing plate 3 is provided with a gradient, the holding posture of the fixing plate 3 on the plate holding unit 11 shown in FIG. 1 can be kept constant regardless of the gradient. Further, from the viewpoint of construction, as shown in FIGS. 9 (E) and 9 (F), an inverted taper-shaped cut is formed on the outside (free end side) of the fixing portion of the fixing plate 3 to the reinforcing bars 40 and 41. It is desirable to provide a notch and make the fixing plate 3 as compact as possible. Further, similar effects can be obtained by providing a curved gradient instead of a linear gradient as shown in FIG. 7G, or by providing a gradient obtained by combining a plurality of straight lines or an arbitrary curve.
[0026]
Further, the fixing plate 3 having a gradient as shown in FIG. 5 not only increases the reinforcing effect, but also facilitates the positioning of the reinforcing steel bar 1 at the time of construction, so that the workability can be improved and improved. In the conventional method in which the reinforcing bar 1 is vertically attached to the fixing plate, there is a possibility that the reinforcing bar 1 is displaced or falls off because there is no effective engagement between the fixing plate 3 and the reinforcing bars 40 and 41. It was necessary to arrange the reinforcing steel bar 1 and fix its position at the same time with a binding wire or the like. According to the fixing plate 3 provided with the gradient, the reinforcing bars 1 can be positioned at the same time as the reinforcing bars are arranged, and the reinforcing bars 1 can be stabilized without a binding wire or the like. If the binding wires and the like can be omitted, the efficiency of the fixing work of the reinforcing steel bar 1 can be remarkably improved.
[0027]
From the viewpoint of facilitating the positioning of the reinforcing reinforcing bar 1, instead of or in addition to the gradient shown in FIG. 5, the locking portions to the reinforcing bars 40 and 41 on the fixing plate 3 as shown in FIG. 7. May be provided with an engagement projection 38 with the reinforcing bars 40 and 41. (A) is a stopper-shaped engaging projection 38a provided on the opposite side of the reinforcing steel bar 1 when viewed from the reinforcing bar 40, (B) is a hemispherical engaging projection 38b, and (C) is the same. Denotes a streamlined wing-shaped engaging projection 38c. FIG. 3D shows an embodiment in which a large number of irregularities provided on the fixing plate 3 are used as the engagement projections 39.
[0028]
5 and 7 can be formed by the above-described arc welding, but can also be formed by conventional hot upsetting or friction welding. For example, the fixing plate 3 with a slope or with the engagement projection 38 is formed or attached to one end of the reinforcing bar 1 by hot upsetting or friction welding, and the fixing plate 3 with a slope or a rotation by rotating the reinforcing bar 1 as shown in FIG. By locking the fixing plate 3 with the engaging projections 38 to the reinforced reinforcing bars 40, the work efficiency can be improved and the reinforcing effect can be increased by omitting the binding wires. In this case, as shown in FIGS. 7A and 7D, the shapes of the engagement projections 38a and 38d are gradually inclined in the direction of locking (the direction of the arrow R in FIG. 6) and the inclination in the opposite direction is steep. By doing so, it is possible to form the engaging projection 38 that is easily engaged and hardly disengaged.
[0029]
8 and 9 show another example of the reinforcing reinforcing bar 1 with the fixing plate 3 used in the present invention. FIG. 8 shows the fixing plate 3 in which the width d2 of the locking portion to the reinforcing bars 40 and 41 is smaller than the width d1 of the fixing portion to the reinforcing bar 1 and is reduced according to the distance from the fixing portion. It was used. For example, according to the arc welding, the reinforcing reinforcing bar 1 and the fixing plate 3 can be firmly joined to each other with a required tensile strength or more, so that the fixing plate 3 can be made smaller than a conventional semicircular hook. By eliminating unnecessary portions of the fixing plate 3 according to the moment distribution and adjusting the shape as shown in FIG. 8, the fixing plate 3 can be made more compact. By making the fixing plate 3 compact and optimally shaped, the so-called head portion of the reinforcing steel bar 1 can be lightened, so that further improvement in workability can be expected, and reduction in material can contribute to reduction in manufacturing cost.
[0030]
In FIG. 8, the width d2 of the fixing portion of the fixing plate 3 to the reinforced bars 40, 41 can be determined according to the distribution of moment applied to the fixing plate 3 from the reinforced bars 40, 41. For example, when the distance from the fixing portion to the reinforcing bar 1 to the locking portion to the reinforced bars 40 and 41 is long, or when the dimensions of the reinforced bars 40 and 41 are large, the moment increases. Therefore, according to the distance from the fixing portion to the reinforcing bar 1 and / or the dimensions of the reinforced bars 40 and 41, the width d2 of the locking portion can be designed as shown in FIGS. The corners can be curved as shown in FIG.
[0031]
FIGS. 9A and 9B show that, in addition to or instead of optimizing the width d of the fixing plate 3, the thickness of the fixing plate 3 at the position where the fixing plate 3 is locked to the reinforcing bars 40 and 41 is changed by the reinforcing reinforcing bar 1. An example is shown in which the thickness is reduced in accordance with the distance from the fixing portion as compared with the thickness of the fixing portion (see FIG. 3C). By adjusting the thickness of the fixing plate 3 according to the moment distribution, the fixing plate 3 can be made more compact, and further improvement in workability can be expected. Also in this case, the thickness of the anchoring portion of the fixing plate 3 to the reinforced reinforcing bars 40, 41 can be determined according to the moment distribution applied from the reinforced bars 40, 41 to the fixing plate 3.
[0032]
The shape of the fixing plate 3 shown in FIGS. 8 and 9 is effectively used not only in the case where the fixing plate 3 is joined to the reinforcing steel bar 1 by arc welding, but also when the fixing portion is formed by a conventional hot upsetting process or a friction welding method. Available. The downsizing of the fixing plate 3 can contribute to an improvement in workability and a reduction in manufacturing cost even when the fixing portion is formed by hot upsetting or friction welding.
[0033]
【The invention's effect】
As described above in detail, the fixing method and the fixing unit forming apparatus for a reinforcing bar according to the present invention provide a mechanism for pressing / pulling a conductive fixing plate opposite to an end of a reinforcing bar disposed on a reinforced bar. Holding the pressing / pulling-off mechanism against the reinforcing bar, connecting the fixing plate and the reinforcing bar to a welding power source, and increasing / decreasing the gap between the fixing plate and the reinforcing bar by the pressing / pulling-off mechanism. As a result, the fixing plate is welded to the end of the reinforcing steel bar, so that the following remarkable effects are obtained.
[0034]
(A) Since the fixing plate can be set after the reinforcing bars are arranged between the reinforcing bars, the reinforcing bars can be efficiently fixed even if the reinforcing bars have a high density.
(B) Since it can be constructed on site, it is possible to cope with a slight variation in arrangement of reinforcing bars, and a predetermined reinforcing effect can be secured.
(C) The simplification and labor saving of the reinforcing bar arrangement work can be achieved, and a contribution to shortening the construction period and cost can be expected.
(D) Since the fixing plate and the reinforcing bar can be joined by welding, it is easy to adjust the mounting angle of the fixing plate with respect to the reinforcing bar.
[0035]
(E) The use of the sloped fixing plate makes it difficult for the fixing plate to fall off from the reinforcing bars, and can maintain the reinforcing effect even when the concrete comes off.
(F) By using the inclined fixing plate, effects such as suppression of buckling of the main reinforcing bar at the time of an earthquake or the like and improvement of toughness of a structure can be expected.
(G) The diameter of the fixing plate can be reduced as compared with the conventional semicircular hook.
(H) By adjusting the shape and thickness of the fixing plate according to the moment distribution, the fixing plate can be made more compact and optimal.
(I) Since the fixing plate and the reinforcing steel can be welded on site, improvement in workability and transportation efficiency during transportation can be expected as compared with the conventional reinforcing steel with plate.
[Brief description of the drawings]
FIG. 1 is an explanatory view of one embodiment of the device of the present invention.
FIG. 2 is an explanatory view of another embodiment of the device of the present invention.
FIG. 3 is an explanatory diagram of an example of a method of welding a reinforcing reinforcing bar and a fixing plate.
FIG. 4 is an explanatory view of another example of a method of welding a reinforcing reinforcing bar and a fixing plate.
FIG. 5 is an explanatory diagram of a gradient of a surface of a fixing plate facing a reinforcing reinforcing bar.
FIG. 6 is an explanatory diagram of an example of a method of fixing a reinforcing bar to which a fixing plate has been welded to a reinforcing bar that has been arranged.
FIG. 7 is an explanatory diagram of an engagement protrusion with a reinforcing bar provided on a fixing plate.
FIG. 8 is a diagram illustrating an example of the shape of a fixing plate.
FIG. 9 is an explanatory diagram of another example of the shape of the fixing plate.
FIG. 10 is an explanatory view of a conventional method of fixing a reinforcing bar to a reinforcing bar that has been arranged.
[Explanation of symbols]
1: Reinforcing reinforcing bar 2: End
3. Fixing plate 4. Opposing surface
5 ... hollow 5a ... bottom wall
5b: groove (slit) 6: rod-shaped projection
7 ... Coating agent 8 ... Ferrule
9: opposite side surface 10: fixing unit forming device
11 holding part 12 holding part
13: Opposite end 14: Pressing mechanism
15 ... Piston rod 15a ... Mounting part
16 ... Piston expanding part
17 ... Cylinder 18 ... Chuck adapter
19 ... Chuck 20 ... Spring
21: Separating mechanism 22: Driver
23 ... Solenoid 24 ... Housing
25 ... handle 26 ... welding power supply
27 ... cable 28 ... cable
29 ... cable 30 ... adjustment part
31 ... Air supply / discharge path 32 ... Air supply / discharge path
33 ... Switch
35 ... formwork 36 ... spacer
38: engagement projection 39: engagement projection
40 ... Reinforced bar 41 ... Reinforced bar

Claims

In a method of fixing a reinforcing bar intersecting with a reinforced bar by a fixing plate fixed to the reinforcing bar, a conductive fixing plate is disposed on the reinforced bar by a plate locking portion of a pressing / pulling-off mechanism. The pressing / pulling-off mechanism is restrained with respect to the reinforcing rebar, the fixing plate and the reinforcing bar are connected to a welding power source, and the pressing / pulling-off mechanism connects the fixing plate and the reinforcing bar with each other. A fixing method for reinforcing bars by welding a fixing plate to an end of the reinforcing bars by adjusting a gap.

2. The method according to claim 1, wherein the welding is performed before the fixing plate is locked to the reinforcing bars.

2. The method according to claim 1, wherein the welding is performed after the fixing plate is locked to the reinforced reinforcing bars.

The method according to any one of claims 1 to 3, wherein a spacer is inserted between the concrete formwork and the end opposite to the welded end of the reinforcement form when the reinforcing reinforcement is oriented so as to intersect the concrete formwork. The fixing method of the reinforcing steel bar which restrains the reinforcing steel bar according to the above.

5. The reinforcing method according to claim 1, wherein a recess having substantially the same diameter as an end of the reinforcing bar is provided on a portion of the fixing plate facing the reinforcing bar, and a ferrule is attached to the recess. How to fix the rebar.

The method according to any one of claims 1 to 4, wherein a recess whose opening end is substantially the same diameter as the end of the reinforcing bar and gradually expands toward the bottom surface is provided at a portion of the fixing plate facing the reinforcing bar, A method of fixing a reinforcing steel bar, wherein a groove in a depth direction from an opening to a bottom wall is provided in an inner peripheral wall of the depression.

5. The method according to claim 1, wherein a bar-shaped protrusion having substantially the same diameter as an end of the reinforcing bar is provided on a portion of the fixing plate facing the reinforcing bar, and a ferrule is attached to a tip of the protrusion. 6. The method of fixing reinforcing steel bars.

The method according to any one of claims 1 to 7, wherein a surface of the fixing plate facing the reinforcing bar is gradually moved from a portion facing the reinforcing bar to an engagement portion of the reinforcing bar with the reinforcing bar. An anchoring method for reinforcing steel bars with a sloping slope.

9. The fixing method of a reinforcing reinforcing bar according to any one of claims 1 to 8, wherein an engaging projection for engaging with the reinforcing bar is provided at a position on the fixing plate where the reinforcing bar is locked to the reinforcing bar.

The method according to any one of claims 1 to 9, wherein a width of a fixing portion of the fixing plate to the reinforced reinforcing bar is larger than a width of a portion facing the reinforcing reinforcing bar, and a distance between the locking portion and the facing portion is smaller. An anchoring method for reinforcing bars that is reduced in size.

The method according to any one of claims 1 to 10, wherein a thickness of a fixing portion of the fixing plate to the reinforced reinforcing bar is compared with a thickness of a portion facing the reinforcing reinforcing bar. A method of fixing reinforcing steel bars that are thinned according to distance.

A grip portion for gripping an end of a reinforcing bar, a plate locking portion for holding a conductive fixing plate facing the edge of the reinforcing bar, and pressing / pulling for moving the locking portion on a predetermined axis toward the grip portion. An apparatus for forming a fixing portion of a reinforcing bar, comprising: a mechanism; and a welding power source connected to the grip portion and the locking portion.

The apparatus according to claim 12, wherein a recess having substantially the same diameter as an end of the reinforcing bar is provided in a portion of the fixing plate facing the reinforcing bar.

14. The device according to claim 13, wherein the recess has an opening end substantially the same diameter as the end of the reinforcing steel bar, and gradually increases in diameter toward the bottom surface, and a depth groove is formed in the inner peripheral wall from the opening to the bottom wall. Fixing part forming device for reinforcing bar.

13. The apparatus according to claim 12, wherein a bar-shaped projection having substantially the same diameter as an end of the reinforcing bar is provided at a portion of the fixing plate facing the reinforcing bar.

The device according to any one of claims 12 to 15, wherein a surface of the fixing plate facing the reinforcing bar gradually moves from a portion facing the reinforcing bar to a locking portion of the reinforcing bar. An apparatus for forming a reinforcing portion of a reinforcing steel bar having a slope toward the head.

The apparatus according to any one of claims 12 to 16, wherein a fixing portion of a reinforcing reinforcing bar is provided at an engagement portion of the fixing plate to the reinforcing bar with an engagement protrusion with the reinforcing bar.

The apparatus according to any one of claims 12 to 17, wherein a width of a fixing portion of the fixing plate to the reinforced reinforcing bar is larger than a width of a portion facing the reinforcing reinforcing bar, and a distance between the locking portion and the facing portion. An apparatus for forming a fixing portion of a reinforcing steel bar reduced according to

The apparatus according to any one of claims 12 to 17, wherein a thickness of a fixing portion of the fixing plate to the reinforced reinforcing bar is smaller than a thickness of a portion facing the reinforcing reinforcing bar. Fixing part forming device for reinforcing steel bar reduced according to the distance of

In a reinforcing bar having a fixing plate fixed to an end portion, which is disposed to intersect with the reinforcing bar and which can be locked to the reinforcing bar, a fixing portion to the reinforcing bar on a surface of the fixing plate facing the reinforcing bar. A reinforcing reinforcing bar with a fixing plate, which is provided with a gradient gradually from the to the portion where the reinforcing bar is engaged with the reinforcing bar.

In a reinforcing reinforcing bar fixed to an end portion, a fixing plate fixed to an end portion is disposed so as to intersect with the reinforcing bar and is fixed to an end of the reinforcing bar. Reinforcing reinforcing bar with fixing plate provided with engaging projections for the finished reinforcing bar.

In a reinforcing bar fixed to an end, a fixing plate fixed to an end and arranged to intersect with a reinforcing bar and fixed to the reinforcing bar, a width of a fixing portion of the fixing plate to the reinforcing bar is set to a reinforcing bar. A reinforcing reinforcing bar with a fixing plate, which is reduced in accordance with the distance between the locking portion and the fixing portion in comparison with the width of the fixing portion to the fixing member.

Reinforcing bars that are fixed to the ends and have fixing plates fixed to the ends and that are fixed to the reinforcing bars and that are intersected with the reinforcing bars and that reinforce the thickness of the fixing portions of the fixing plates to the reinforcing bars A reinforcing reinforcing bar with a fixing plate, which is reduced in accordance with the distance between the locking portion and the fixing portion as compared with the thickness of the fixing portion to the reinforcing bar.