JP4006497B2

JP4006497B2 - Constituent material and horizontal member of building civil engineering structure with opening reinforcement structure

Info

Publication number: JP4006497B2
Application number: JP2002225717A
Authority: JP
Inventors: 久廣平石
Original assignee: Meiji University
Current assignee: Meiji University
Priority date: 2002-08-02
Filing date: 2002-08-02
Publication date: 2007-11-14
Anticipated expiration: 2022-08-02
Also published as: JP2004068303A

Description

【０００１】
【発明の属する技術分野】
本発明は横架材等、建築構造物や土木構造物の構成材に貫通形成された開口を補強する構造に関する。
【０００２】
【従来の技術】
鉄筋コンクリート造の梁（横架材）は、複数の上側主筋と、複数の下側主筋と、これら主筋を囲み主筋の延び方向に間隔をおいて配置された多数の剪断補強筋と、これら主筋および剪断補強筋を埋め込むコンクリートとにより構成されている。この梁に空調設備ダクト等を通すため、梁の長手方向と直交する方向に開口を貫通形成することがある。
【０００３】
上記開口を形成した場合、梁の強度、特に梁の開口の周囲の強度が低下し、地震の際に、コンクリートのひび割れ，剥離等の損傷が生じることがある。そこで、従来から種々の開口補強構造が提案されている。例えば特開平６−１４６４７４号の図４（Ａ）に示すように、開口の回りを複数の傾斜鉄筋で囲ったり、同公報の図１に示すように、開口を囲むリング筋を配置することにより、開口を補強しようとしている。
【０００４】
【特許文献１】
特開平６−１４６４７４号公報（図１，図４Ａ）
【０００５】
【発明が解決しようとする課題】
上記公報の梁の開口補強構造では、傾斜鉄筋やリング筋は梁主筋と力の伝達関係を持たない。そのため、開口を設けたことによる剪断耐力の低下を防止するには限度があった。
【０００６】
【課題を解決するための手段】
第１の発明は上記課題を解決するためになされたものであり、直線状に第１方向に延びる複数の主筋と、主筋を囲み上記第１方向に間隔をおいて配置された多数の剪断補強筋と、これら主筋および剪断補強筋を埋め込むコンクリートと、上記第１方向と直交する第２方向に貫通形成された開口を補強する開口補強構造と、を備えた建築土木構造物の構成材において、上記開口補強構造が、第１，第２の開口補強筋を備え、これら第１，第２の開口補強筋は、略Ｕ字状をなす補強部と、この補強部の両端に連なる引掛部とを有し、第１開口補強筋の引掛部は、上記第１，第２方向と直交する第３方向の一方側に配置された主筋に掛けられ、第２開口補強筋の引掛部は上記第３方向の他方側の主筋に掛けられ、これら第１，第２の開口補強筋の補強部が、上記開口を少なくとも略半周分ずつ囲んでいることを特徴とする。図１〜図１２の実施形態参照。
【０００７】
上記構成によれば、第１，第２の開口補強筋のＵ字状の補強部で開口を囲む。しかも、これら開口補強筋は引掛部によりそれぞれ主筋に掛けられ、主筋への力の伝達経路を確保しているので、構成材の開口の周囲部に生じた剪断力を最終的に主筋で受け持つことができる。その結果、開口の周囲部分でのコンクリートの損傷を著しく軽減できる。また、これら開口補強筋は比較的簡単な構成にできるとともに、設置作業も容易である。
【０００８】
第２の発明は、建築土木構造物の構成材において、上記開口補強構造が開口補強筋を備え、この開口補強筋は、上記第１，第２方向と直交する第３方向の一方側の主筋から他方側の主筋まで延びる補強部と、この補強部の両端に連なる引掛部とを有し、これら引掛部が上記一方側の主筋と他方側の主筋にそれぞれ掛けられ、上記補強部の略中央部には、上記開口を囲むように巻回された環状部が形成されていることを特徴とする。図１３，図１４の実施形態参照。
この構成では、開口補強筋の環状部が開口を囲む。しかも、この開口補強筋の引掛部が対峙する主筋に掛けられ主筋への力の伝達経路を確保しているので、第１発明と同様に開口の周囲部分でのコンクリートの損傷を著しく軽減できる。また、これら開口補強筋は比較的簡単な構成にできるとともに、設置作業も容易である。
【０００９】
第３の発明では、複数の上側主筋と、複数の下側主筋と、これら主筋を囲み主筋の延び方向に間隔をおいて配置された多数の剪断補強筋と、これら主筋および剪断補強筋を埋め込むコンクリートと、主筋の延び方向と直交する方向に貫通形成された開口を補強する開口補強構造とを備えた建築土木構造物の構成材において、
上記開口補強構造が、第１，第２の開口補強筋を備え、第１開口補強筋は、略Ｕ字状をなして垂れ下がる補強部と、この補強部の一対の上端に連なり上側主筋に掛けられる引掛部とを有し、第２開口補強筋は、略Ｕ字状をなして起き上がる補強部と、この補強部の一対の下端に連なり下側主筋に掛けられる引掛部とを有し、上記第１の開口補強筋の補強部が上記開口の少なくとも下側の略半周分を囲み、第２の開口補強筋の補強部が上記開口の少なくとも下側の略半周分を囲んでいることを特徴とする。図１〜図１２の実施形態参照。
上記第３発明は、第１発明を横架材に限定したものであり、第１発明と同等の作業効果が得られる。
【００１０】
上記第３の発明の一態様として、上記第１，第２の開口補強筋の各々は、１本の連続した鉄筋により形成され、上記補強部を一対有するとともに、上記開口の貫通方向に延びる少なくとも１つの直線部を有し、この直線部が上記一対の補強部の一端に連なって共通の引掛部として提供され、この直線部と一対の補強部との間の２つの交差部が２本の主筋にそれぞれ掛けられている。図１〜図８の実施形態参照。
この構成によれば、一対の補強部が１回の作業で設置でき、設置作業がより一層容易になる。また、一対の補強部の少なくとも一端が１つの直線部で連なっており、この直線部が複数の主筋に掛けられるので、補強部から主筋への力の伝達をより一層確実なものとすることができる。
【００１１】
上記第１，第２の開口補強筋の各々は、主筋の延び方向に離れた一対の直線部を備えており、上記鉄筋の両端が溶接されることにより、閉ループをなして形成されていていてもよい。図１〜図７の実施形態参照。
この構成によれば、開口補強筋が閉じループをなすとともに、２つの直線部がそれぞれ複数の主筋に掛かりようになっているので、構成の簡略化、設置作業の容易化、補強部から主筋への力の伝達を、最大限発揮することができる。
【００１２】
上記鉄筋の両端部は、上記引掛部の一部を構成し、それぞれ折り曲げられて主筋に掛けられていてもよい。図８参照。この構成によれば、鉄筋の溶接が不要となる。
好ましくは、上側主筋および下側主筋がそれぞれ４本以上配置され、上記第１，第２開口補強筋がそれぞれ複数設けられ、上記複数の第１開口補強筋の補強部が、上記開口の貫通方向に離れて配置され、上記複数の第２開口補強筋の補強部が、第１開口補強筋の補強部にそれぞれ重なるように配置されている。図１〜図７に示す実施形態参照。この構成によれば、第１，第２開口補強筋はそれぞれ４つ以上の補強部を有して開口を囲むので、補強効果を増大させることができる。
【００１３】
第３の発明の他の態様として、上記第１，第２の開口補強筋が複数装備され、これら開口補強筋の各々は、連続した１本の鉄筋により単一の補強部を有して形成され、第１開口補強筋の補強部同士、第２開口補強筋の補強部同士が、上記開口の貫通方向に離れている。図９に示す実施形態参照。この構成によれば、開口補強筋の構成をより一層簡略化することができる。
上記第１，第２の開口補強筋の各々において、補強部の両端部が折り曲げられて一対の引掛部として提供され、この一対の引掛部が共通の主筋に掛けられるようにしてもよい。図９（Ｃ）に示す実施形態参照。この構成によれば、開口補強筋の構成を最大限に簡略化することができる。
上記第１，第２の開口補強筋の各々は、上記補強部の両端から上記開口の貫通方向に直線的に延びる一対の引掛部を有し、これら一対の引掛部と補強部との交差部が１本の共通の主筋に掛けられ、この引掛部の先端部が折り曲げられて他の共通の主筋に掛けられるようにしてもよい。図９（Ａ），（Ｂ）に示す実施形態参照。この構成によれば、引掛部が複数の主筋に掛けられるので、開口補強筋を安定して設置することができる。
【００１４】
上記第３の発明の他の実施形態として、上側主筋および下側主筋が４本ずつ配置され、上記第１，第２開口補強筋が１つずつ設けられ、これら第１，第２開口補強筋の各々は、１本の連続した鉄筋により形成され、この鉄筋を折り曲げることにより、４つの補強部と、この補強部に連なる直線状の引掛部とを有し、第１開口補強筋における補強部と引掛部との交差部が上側の４本の主筋にそれぞれ掛けられ、第２開口補強筋における補強部と引掛部との交差部が下側の４本の主筋にそれぞれ掛けられている。図１０に示す実施形態参照。
この構成によれば、第１，第２開口補強筋の設置作業はそれぞれ１回ずつで済むので、設置作業を最大限簡略化させることができる。また、４つの主筋に掛けられるので、主筋への力の伝達も最大限発揮できる。
【００１５】
第３の発明の他の態様として、上記第１，第２の開口補強筋の補強部は、直線を複数箇所で折り曲げるようにして形成され、第１，第２の開口補強筋のそれぞれにおいて、複数の補強部の対応する折り曲げ部が、上記開口の貫通方向から見て一致した位置にあり、開口の貫通方向に延びる補助筋が、この折り曲げ部にほぼ接するようにしてその内側に配置されている。図１１，図１２に示す実施形態参照。この構成によれば、補助筋を開口に沿える構造であるので、開口補強効果を増大させることができる。
【００１６】
第４の発明は、建築土木構造物の横架材において、上記開口補強構造が開口補強筋を備え、この開口補強筋は、上側主筋から下側主筋まで延びる補強部と、この補強部の上端に連なり上側主筋に掛けられる第１引掛部と、この補強部の下端に連なり下側主筋に掛けられる第２引掛部とを有し、上記補強部の略中央部には、上記開口を囲むように巻回された環状部が形成されていることを特徴とする。図１３，図１４に示す実施形態参照。
上記第４の発明は、第２発明を横架材に限定したものであり、第２発明と同等の作業効果が得られる。
【００１７】
第４の発明において、上記開口補強筋は、連続した１本の鉄筋からなり、上記開口の貫通方向に離れた一対の補強部と、少なくとも１つの直線部とを有し、この直線部は、上記開口の貫通方向に水平に延び一対の補強部の一方の端に連なって共通の引掛部として提供され、この直線部と一対の補強部との交差部が２本の主筋に掛けられている。図１３，図１４に示す実施形態参照。
この構成によれば、一対の補強部が１回の作業で設置でき、開口補強筋の設置作業がより一層容易になる。また、一対の補強部の少なくとも一端が１つの直線部で連なっており、この直線部が複数の主筋に掛けられるので、補強部から主筋への力の伝達をより一層確実なものとすることができる。
【００１８】
好ましくは、上記開口補強筋は、上記鉄筋の両端を溶接することにより、一対の直線部と一対の補強部とを有して略矩形状に形成されている。図１３，図１４に示す実施形態参照。これにより、開口補強筋は剪断補強筋とほぼ等しい役割をも果たすことができる。
好ましくは、上記開口補強筋は、主筋の延び方向に離れて一対配置され、これら一対の開口補強筋の環状部が上記開口の貫通方向から見て同位置にあって上記開口を囲む。図１３，図１４に示す実施形態参照。これにより、開口周囲において剪断補強筋の代わりに開口補強筋を密に配置することができる。また、開口を囲む環状部の数を増やすことができる。
【００１９】
好ましくは、上記開口補強構造は、さらに主筋の延び方向と直交する方向に配置されたパイプを備え、このパイプの内部空間が上記開口として提供される。全ての図に示す実施形態参照。このパイプにより、剪断に伴う圧縮力を伝達することができる。また、パイプと主筋との間のコンクリートを有効に拘束できることから、開口周囲の補強効果をさらに高めることができるとともに、開口内周面からのコンクリートの剥落を防止することができる。
さらに好ましくは、上記パイプの外周には、コンクリートとの付着を高めるための凹凸が形成されている。これにより更なる補強効果が得られる。
【００２０】
【発明の実施の形態】
以下、本発明の第１実施形態について、図１〜図７を参照しながら説明する。図１〜図４は、梁１０（建築物の構成材としての横架材）を示す。梁１０は、梁１０の長手方向（第１方向）に沿って水平に延びる４本の上側主筋１１（第３方向の一方側の主筋）と４本の下側主筋１２（第３方向の他方側の主筋）と、これら主筋１１、１２を囲む、縦長の四角形をなす多数の剪断補強筋１３（スターラップ）とを有している。４本の上側主筋１１は共通の平面上に平行に配置されており、４本の下側主筋１２も他の共通の平面上に平行に配置されている。剪断補強筋１３は、梁１０の長手方向（主筋１１，１２の延び方向）に一定間隔をおいて配置されている。剪断補強筋１３の４つの隅部は、上側の左右両端の主筋１１と下側の左右両端の主筋１２に掛けられ、主筋１１，１２に番線（細い金属線）で結ばれて位置決めされている。これら主筋１１，１２および剪断補強筋１３はコンクリート１４（図６（Ｃ）にのみ示す）内に埋設されている。
【００２１】
梁１０の開口形成領域Ｘには剪断補強筋１３は配置されていない。本実施形態では、剪断補強筋１３が２つ分欠けている。図４，図５（Ｃ），図６（Ｃ）に示すように、この開口形成領域Ｘに開口Ｈが形成されるとともに、開口補強構造２０が設けられている。この開口補強構造２０は、上側の２つの第１開口補強筋２１と、下側の２つの第２開口補強筋２２と、鋼管（パイプ）２３とを有している。
【００２２】
上記第１開口補強筋２１は、図７（Ｂ）に最も良く示されているように、Ｕ字形をなす一対の補強部２１ａと、これら一対の補強部２１ａの一端間を連ねる直線部２１ｂと、一対の補強部２１ａの他端間を連ねる直線部２１ｂとを有して、閉ループを形成している。直線部２１ｂは、一対の補強部２１ａのための共通の引掛部として提供される。図５（Ｃ），図７（Ｂ）に示すように、補強部２１ａは、補強部２１ａに連なる一対の直線状の垂直部２１ｘとこれら垂直部２１ｘの下端を連ねる半円弧形状の湾曲部２１ｙとからなる。補強部２１ａと直線部２１ｂとの交差部２１ｚは、主筋１１の外周に対応する曲率半径で湾曲している。
【００２３】
第２開口補強筋２２は第１開口補強筋２１と等しい形状をなし、一対の補強部２２ａと一対の直線部２２ｂ（共通の引掛部）とを有している。補強部２２ａは一対の垂直部２１ｘと湾曲部２１ｙとからなり（図５（Ｃ）でのみ符号を付けて示す）、補強部２２ａと直線部２２ｂとの交差部２２ｚは湾曲している。
【００２４】
上記開口補強筋２１，２２はそれぞれ１本の連続した鉄筋により形成されている。最初に連続した１本の鉄筋を折り曲げて図７（Ａ）に示すような枠体５０を作る。この枠体５０は、一対の長辺部５１と一対の短辺部５２とを有して長方形をなしている。鉄筋の両端は突き合わされて溶接されている。この溶接部５５は、枠体５０の例えば一方の短辺部５２の中央（中間部）に位置している。次に、この長方形の枠体５０を図７（Ａ）の矢印で示すように、枠体５０の一対の短辺部５２が近づくように、一対の長辺部５１の中央部を円弧形状に湾曲する。この湾曲された長辺部５１が開口補強筋２１、２２の補強部２１ａ、２２ａとなり、短辺部５２がそのまま開口補強筋２１の直線部２１ｂ，２２ｂとなる。
【００２５】
図４，図５（Ｃ），図６（Ｃ）に示すように、第１開口補強筋２１の直線部２１ｂは上側の主筋１１と直交して水平に延びこの主筋１１の上側に掛けられており、補強部２１ａは後述する鋼管２３の貫通方向（第２方向）と直交する垂直面上において垂れ下がっている。詳述すると、一方の第１開口補強筋２１の一対の直線部２１ｂは、主筋１１の延び方向に互いに離れているとともに、上側の主筋１１のうち左から１番目〜３番目までの３本の主筋１１に掛けられており、その交差部２１ｚは左端の主筋１１と３番目の主筋１１に掛けられている。他方の第１開口補強筋２１の一対の直線部２１ｂも互いに離れているとともに、左から２番目〜４番目の主筋１１に掛けられており、その交差部２１ｚは２番目の主筋１１と４番目の主筋１１に掛けられている。２つの第１開口補強筋２１の直線部２１ｂは一部重なっている。２つの第１開口補強筋２１の一対の補強部２１ａ、すなわち４つの補強部２１ａは互いに離れており、異なる主筋１１から垂れ下がっている。
【００２６】
同様に、第２開口補強筋２２の直線部２２ｂは下側の主筋１２と直交して水平に延びこの主筋１２の下側に掛けられている。補強部２２ａは鋼管２３の貫通方向と直交する垂直面上において起き上がっている。一方の第２開口補強筋２２の一対の直線部２２ｂは、互いに離れているとともに、下側の主筋１２のうち左から１番目〜３番目までの３本の主筋１２に掛けられており、その交差部２２ｚは左端の主筋１２と３番目の主筋１２に当たっている。他方の第２開口補強筋２２の直線部２２ｂは、互いに離れているとともに、左から２番目〜４番目の主筋１２に掛けられており、その交差部２２ｚは２番目の主筋１２と４番目の主筋１２に当たっている。２つの第１開口補強筋２２の一対の補強部２２ａ、すなわち４つの補強部２２ａは互いに離れており、異なる主筋１２から起き上がっている。上記開口補強筋２１，２２は、位置決めのために番線により主筋１１，１２に連結されている。
【００２７】
図５（Ｃ）に最も良く示されているように、第１開口補強筋２１の補強部２１ａと第２補強筋２２の補強部２２ａとは、紙面と直交する方向（梁１０の延び方向と直交し、水平な方向）から見て交差している。また、図６（Ｃ）に示すように、第１開口補強筋２１の補強部２１ａとこれに対応する第２補強筋の補強部２２ａは重なっている。この補強部２１ａ，２２ａにより形成された環状のスペースに鋼管２３が挿入されている。この鋼管２３の内部空間が上記開口Ｓとして提供される。各補強部２１ａ，２２ａは鋼管２３（開口Ｓ）を半周ずつ囲んでいることになる。
【００２８】
次に、開口補強構造２０の製造工程について説明する。図１，図２，図５（Ａ），図６（Ａ），（Ｂ）に示すように、一方の第１開口補強筋２１の直線部２１ｂを上側の３本の主筋１１に載せて、一対の補強部２１ａを垂れ下がるように配置するとともに、他方の第１開口補強筋２１の直線部２１ｂを上側の３本の主筋１１に載せて、一対の補強部２１ａを垂れ下がるように配置する。そして、これら直線部２１ｂを番線で主筋１１に結ぶ。
上記と同様にして、図２，図３，図５（Ｂ），図６（Ｂ），（Ｃ）に示すように、第２開口補強筋２２を下側の主筋１２に取りつける。なお、これら４つの開口補強筋２１，２２の取り付け順序は特にこだわらない。
次に、図４，図５（Ｃ），図６（Ｃ）に示すように、開口補強筋２１，２２の補強部２１ａ，２２ａの交差により形成された環状のスペースに鋼管２３を挿入する。最後にコンクリート１４を打設する。
【００２９】
上記梁１０の開口Ｓには空調設備のダクト等が挿通される。開口Ｓの周囲のコンクリート１４は、開口補強筋２１，２２により補強されているので、地震の際のひび割れ等を著しく軽減できる。すなわち、梁１０に大きな剪断力が作用した場合には、開口Ｓを囲んだ開口補強筋２１，２２の補強部２１ａ，２２ａでこれを受け持ち、直線部２１ｂ、２２ｂが掛けられた主筋２１、２２に伝達するので、最終的にこの主筋２１，２２で剪断力を受け持つことができるからである。鋼管２３は、剪断に伴う圧縮力を伝達することができる。また、鋼管２３と主筋１１，１２との間のコンクリート１４を有効に拘束することができることから、コンクリート１４の開口Ｓの周囲部分の補強の役割を果たすとともに、開口Ｓ近傍のコンクリートの剥落を防止する役割を担う。
鋼管２３の外周には、コンクリート１４との付着性を高めるために全域にわたって凹凸が形成されており、より一層の補強効果を得ている。なお、この凹凸は、例えば鋼管２３の軸方向に延びる多数の縦リブと周方向に延びる横リブにより硬性されている。
【００３０】
本実施形態において、１本の連続した鉄筋により形成された開口補強筋２１，２２は構成が簡単である。開口補強筋２１，２２は主筋１１，１２に掛けるようにして設置できるので、その設置作業が簡単である。しかも、交差部２１ｚ，２２ｚを主筋１１，１２に掛けることにより、位置決めも簡単である。
【００３１】
本発明は、上記第１実施形態に制約されず、種々の形態を採用できる。例えば、図５（C）に示すように、短い鉄筋からなる補助筋２９を、鋼管２３の上下に主筋１１，１２と平行に配置してもよい。
第１実施形態より開口補強筋２１，２２の直線部２１ｂ、２２ｂを短くして、隣接する２本の主筋１１，１２に掛けるようにしてもよい。例えば、一方の第１開口補強筋２１を左から１番目と２番目の主筋１１に掛け、他方の第１補強筋２１を左から３番目と４番目の主筋１１に掛けるようにし、２つの第２開口補強筋２２も同様にして主筋１２に掛けるようにする。
【００３２】
次に、本発明の他の実施形態を図面を参照しながら説明する。これら実施形態において先行の実施形態に対応する構成部には同番号を付してその詳細な説明を省略する。
図８，図９に示す実施形態では、第１実施形態と同様に開口補強筋は１本の連続した鉄筋により形成されているが、その両端は溶接されず折り曲げられている。これら実施形態において、第２開口補強筋は第１補強筋と同形状であるから説明を省略する。
【００３３】
図８（Ａ）に示す実施形態の第１開口補強筋２１Ａでは、一方の直線部２１ｂは第１実施形態と同様に一対の補強部２１ａの一端を連ねて共通の引掛部として機能するが、他方の直線部２１ｂ’は一方の補強部２１ａの他端のための引掛部としてだけの役割を担い、３本の主筋１１に掛けられている。他方の補強部２１ａの他端部は折り曲げられて引掛部２１ｃとなっている。この引掛部２１ｃと、上記直線部２１ｂ’の先端部に形成された折曲部２１ｄは、共通の主筋１１に掛けられている。
【００３４】
図８（Ｂ）に示す実施形態の第１開口補強筋２１Ｂでは、一方の直線部２１ｂは第１実施形態と同様に一対の補強部２１ａの一端を連ねて共通の引掛部として機能する。一対の補強部２１ａの他端には、引掛部としての直線部２１ｂ”がそれぞれ連なっている。これら２本の直線部２１ｂ”は第１実施形態の半分の長さであり、それぞれ２本の主筋１１に掛けられ、その先端部に形成された折曲部２１ｅは真中の主筋１１に掛けられる。
【００３５】
図８（Ｃ）に示す実施形態の第１開口補強筋２１Ｃでは、１つの直線部２１ｂが第１実施形態と同様に一対の補強部２１ａの一端を連ねて共通の引掛部として機能する。一対の補強部２１ａの他端部には、折曲部２１ｆ（引掛部）が形成されている。これら折曲部２１ｆは対応する交差部２１ｚと共通の主筋１１に掛けられている。
【００３６】
上記図８（Ａ）の実施形態では、直線部２１ｂ、２１ｂ’を略半分の長さにして２本の主筋１１に掛けるようにしてもよい。同様に図８（Ｂ），（Ｃ）でも直線部２１ｂを短くして２本の主筋１１に掛けるようにしてもよい。
【００３７】
図８（D）の実施形態の第１開口補強筋２１Ｄは図８（Ｂ）の実施形態と似ているが、直線部２１ｂを長くして４本の主筋１１に掛けるようになっている。２本の直線部２１ｂ”はそれぞれ異なる２本の主筋１１に掛けられる。
図８（Ｅ）の実施形態の第１開口補強筋２１Ｅも図８（Ｂ）の実施形態と似ているが、直線部２１ｂを長くして４本の主筋１１に掛けるようになっている。２本の直線部２１ｂ”も長くなっていて３本の主筋１１に掛けられる。
【００３８】
図９（Ａ）〜（Ｃ）に示す実施形態では、開口補強筋は、単一の補強部を有している。この実施形態では、第１開口補強筋，第２開口補強筋は、それぞれ複数例えば２つ配置される。図９（Ａ）に示す第１開口補強筋２１Ｆは、補強部２１ａと、この補強部２１ａの両端から延びる直線部２１ｇ（引掛部）と有している。直線部２１ｇは３本の主筋１１に掛けられ、その先端の折曲部２１ｈが、中間の主筋１１に掛けられている。
図９（Ｂ）に示す第１開口補強筋２１Ｇは、図９（Ａ）の第１開口補強筋２０Ａより直線部２１ｇが短く２本の主筋１１に掛けられている。
図９（Ｃ）に示す第１開口補強筋２１Ｈは、図９（Ａ），（Ｂ）の直線部２０ｇがなく、補強部２１ａの両端部に折曲部２１ｈ（引掛部）が形成されている。
【００３９】
図１０に示す実施形態では、最初に１本の鉄筋を一筆書きのようにして折り曲げてその両端を溶接することにより、長方形の枠体６０を作る。枠体６０は一対の長辺部６１と、これら長辺部６１と平行をなしその内側に配置された一対の中骨部６２と、これら長辺部６１および中骨部６２と直交する一対の短辺部６３とを有している。長辺部６１と中骨部６２はほぼ等間隔をなしている。一方の短辺部６３は、一対の長辺部６１の一端間を連ねる長い直線部６３ａと、一対の中骨部６２の一端間を連ねる短い直線部６３ｂとを含み、この直線部６３ｂは直線部６３ａの中央部で重なっている。他方の短辺部６３は、一方の長辺部６１の他端と一方の中骨部６２の他端間を連ねる直線部６３ｃと、他方の長辺部６１の他端と他方の中骨部６２の他端間を連ねる直線部６３ｄとを含み、これら直線部６３ｃ、６３ｄは短辺部６３の中央部で重なっている。鉄筋の両端は突き合わされて溶接されている。この溶接部６５は、例えば枠体６０の短辺部６３の直線部の１つである直線部６３ｄの中間部に位置している。
【００４０】
次に、図１０の矢印で示すように、一対の短辺部６３が近づくように、長辺部６１，中骨部６２の中央部を円弧形状に湾曲する。これにより、湾曲された長辺部６１，中骨部６２が開口補強筋の補強部となる。また、短辺部６３を構成する直線部６３a，６３ｂおよび直線部６３ｃ、６３ｄがそのまま開口補強筋２１の直線部（引掛部）となる。全体形状は、第１実施形態の２つの開口補強筋２１を一体に組み込んだ形状に似る（図１参照）。直線部６３ａ〜６３ｄと長辺部６１，中骨部６２の交差部は湾曲していてそれぞれ４本の主筋１１に掛けられる。
【００４１】
図１１に示す実施形態の開口補強構造２０Ｊは、第１開口補強筋２１Ｊと第２開口補強筋２２Ｊと、鋼管２３と、鋼管２３とほぼ同じ長さか少し短い直線状の鉄筋からなる補助筋２５とを有している。これら開口補強筋２１Ｊ，２２Ｊは第１実施形態の開口補強筋２１，２２と基本構成が同じであり、２つずつ配置される。これら開口補強筋２１Ｊ，２２Ｊの補強部２１ａ’，２２ａ’の形状だけが第１実施形態と異なる。第１開口補強筋２１Ｊの一対の補強部２１ａ’は、略Ｕ字状をなすが、直線を２箇所（複数箇所）で折り曲げるようにして左右対称に形成され、一対の補強部２１ａの折り曲げ部２１ｐ同士，折り曲げ部２１ｑ同士が上記開口Ｓの貫通方向から見て一致した位置にある。補助筋２５は、開口Ｓの貫通方向に延び、折り曲げ部２１ｐ，２１ｑにほぼ接するようにしてその内側に配置され、番線で結束されている。
【００４２】
第２開口補強筋２２Ｊの補強部２２ａ’も同様に折り曲げ部２２ｐ、２２ｑを有し、ここに補助筋２５が配置されている。この実施形態では、４本の補助筋２５を配置することにより、開口Ｓの周囲の強度を更に向上させることができる。
【００４３】
図１２に示す実施形態の開口補強構造２０Ｋにおいては、第１開口補強筋２１Ｋの略Ｕ字状の左右対称形をなす補強部２１ａ”は、３箇所に折り曲げ部２１ｒ，２１ｓ，２１ｔを有しており、第２開口補強筋２２Ｋの補強部２２ａ”も、同様にして３箇所に折り曲げ部２２ｒ，２２ｓ，２２ｔを有しているが、他の点は図１１の実施形態と同じである。開口補強筋２１Ｋ，２２Ｋの折り曲げ部２１ｒ，２２ｒは開口Ｓの貫通方向から見て一致しており、その内側に接するようにして共通の補強筋２５が配置されている。同様に開口補強筋２１Ｋ，２２Ｋの折り曲げ部２１ｔ，２２ｔも開口Ｓの貫通方向から見て一致しており、その内側に接するようにして共通の補強筋２５が配置されている。なお、第１開口補強筋２１Ｋの一対の補強部２１ａ”の折り曲げ部２１ｓ同士、第２開口補強筋２２Ｋの一対の補強部２２ａ”の折り曲げ部２２ｓ同士も開口Ｓの貫通方向から見て一致しており、その内側に補助筋２５が配置されている。
【００４４】
図１１，１２に示す補強部の形状および補助筋の配置は、それより前に説明した全ての実施形態で採用することができる。
また、上述した全ての実施形態において、第１，第２の開口補強筋の補強部の先端部が環状をなしてそれぞれ開口を略一周半ずつ囲むようにしてもよい。この場合にも、補強部は概略的にはＵ字形をなしている。
【００４５】
次に図１３の実施形態について説明する。この実施形態では図１３（Ｂ）に示すように、開口補強筋８０は、上側主筋１１から下側主筋１２まで垂直に延びる一対の補強部８１と、これら補強部８１の上端に連なり上側主筋１１と直交するように水平に直線状に延びる第１引掛部８２と、この補強部８１の下端に連なり下側主筋１２と直交するように水平に延びる第２引掛部８３とを有して、略矩形状に形成されている。上記補強部８１の略中央部には、円形の環状部８１ａが形成されている。
【００４６】
上記開口補強筋８０は１本の連続した鉄筋により形成されている。最初に鉄筋を折り曲げて図１３（Ａ）に示すような枠体９０を作る。この枠体９０は、一対の長辺部９１と一対の短辺部９２とを有して長方形をなしている。鉄筋の両端は突き合わされて溶接されている。この溶接部９５は、枠体９０の例えば一方の短辺部９２の中央（中間部）に位置している。次に、この枠体９０の長辺部９１を中央部で１回りするように曲げ加工する。この曲げ加工された一対の長辺部９１が開口補強筋８０の補強部８１となり、一対の短辺部９２がそのまま開口補強筋８０の第１，第２の引掛部８２，８３となる。なお、溶接部９５は補強部８１の直線部に位置するようにしてもよい。
【００４７】
図１３（Ａ）に示すように、上記開口補強筋８０を、剪断補強筋と同様に全ての主筋１１，１２を囲むようにして配置し、補強部８１と引掛部８２，８３の４つの交差部８４を上側の両端の主筋１１および下側の両端の主筋１２に掛ける。本実施形態では、図１３（Ｃ）に示すように上記形状の開口補強筋８０を２つ用いる。これら２つの開口補強筋８０は、環状部８１ａを互いに向かい合わせる。図１３（Ｄ）に示すように、２つの開口補強筋８０を剪断補強筋とほぼ等しい間隔で配置し、２つの開口補強筋８０の環状部８１ａを、後述の鋼管２３の貫通方向から見て一致させる。この状態で開口補強筋８０を主筋１１，１２に番線で結束し、最後に、４つの環状部８１ａに鋼管２３を通した後、コンクリートを打設する。
【００４８】
図１４に示す実施形態に示す開口補強筋８０’は、図１３の実施形態と似ている。異なるのは補強部８１’がく字形に折れ曲がっている点と、環状部８１ａ’が四角形をなしている点だけである。他の構成部には同番号を付してその説明を省略する。本実施形態でも、２つの開口補強筋８０’の環状部８１ａ’を一致させて配置する。
【００４９】
上述した全ての実施形態において、鋼管の代わりに塩ビ管等の他の材料のパイプを用いてもよいし、パイプを省いてもよい。パイプを省く場合には、補強筋と開口内周との間に十分なコンクリートかぶり厚さをとることは勿論である。
本発明は、土木構造物における横架材等の構成材にも適用できる。
【００５０】
【発明の効果】
以上説明したように本発明によれば、簡単な構成の開口補強構造を用いて、横架材等、建築土木構造物の構成材の開口周囲部分におけるコンクリートのひび割れ等の損傷を著しく軽減することができる。また、開口補強構造の設置作業も容易である。
【図面の簡単な説明】
【図１】本発明の第１実施形態をなす梁の開口補強構造の組み立て工程において、第１段階が開始される直前の状態を示す斜視図である。
【図２】同組み立て工程において、第１段階が完了し、第２段階が開始される直前の状態を示す斜視図である。
【図３】同組み立て工程において、第２段階が完了した状態を示す斜視図である。
【図４】同組み立て工程において、第３段階が完了した状態を示す斜視図である。
【図５】上記開口補強構造の組み立て工程を順を追って示す側面図であり、（Ａ）は同組み立て工程の第１段階が完了した状態を示し、（Ｂ）は同組み立て工程の第２段階が完了した状態を示し、（Ｃ）は同組み立て工程の第３段階が完了した状態を示す。
【図６】上記開口補強構造の組み立て工程を順を追って示す縦断面図であり、（Ａ）は第１段階が開始される直前の状態を示し、（Ｂ）は第１段階が完了し第２段階が開始される直前の状態を示し、（Ｃ）は第２段階および第３段階が完了した状態を示す。
【図７】上記開口補強構造に用いられる開口補強筋の製造方法を示す斜視図であり、（Ａ）は１本の鉄筋を曲げ加工して得られた枠体を示し、（Ｂ）はこの枠体を曲げ加工して最終的に得られた開口補強筋を示す。
【図８】（Ａ）〜（Ｅ）は、第１実施形態と同様に一対の補強部を有するタイプの開口補強筋の他の実施形態をそれぞれ示す斜視図である。
【図９】（Ａ）〜（Ｃ）は、単一の補強部を有するタイプの開口補強筋をそれぞれ示す斜視図である。
【図１０】本発明のさらに他の実施形態をなす開口補強筋の最終加工前の状態である枠体を示す斜視図である。
【図１１】本発明のさらに他の実施形態をなす開口補強構造を示す側面図である。
【図１２】本発明のさらに他の実施形態をなす開口補強構造を示す側面図である。
【図１３】上下の梁主筋に掛け渡されるタイプの開口補強筋を示すものであり、（Ａ）は開口補強筋の最終加工前の状態である枠体を示す斜視図であり、（Ｂ）は同開口補強筋を示す斜視図であり、（Ｃ）は同開口補強筋を一対用意して梁主筋に通した状態を示す側面図であり、（Ｄ）は一対の開口補強筋の補強部を一致させるように位置決めして鋼管を挿入した状態を示す側面図である。
【図１４】上下の梁主筋に掛け渡されるタイプの開口補強筋の他の例を示すものであり、（Ａ）は同開口補強筋を一対用意して梁主筋に通した状態を示す側面図であり、（Ｂ）は一対の開口補強筋の補強部を一致させるように位置決めした状態を示す側面図である。
【符号の説明】
１０梁（建築物の構成材，横架材）
１１上側主筋
１２下側主筋
１３剪断補強筋
１４コンクリート
２０，２０Ｊ，２０Ｋ開口固定構造
２１，２１Ａ〜２１Ｋ第１開口補強筋
２２，２２Ａ〜２２Ｋ第２開口補強筋
２１a，２１ａ’，２１ａ”，２２ａ，２２ａ’，２２ａ” 補強部
２１ｂ，２１ｂ’、２２ｂ直線部（引掛部）
２１ｆ折曲部（引掛部）
２１ｚ交差部
２１p，２１ｑ，２１ｒ，２１ｓ，２１ｔ折り曲げ部
２３鋼管（パイプ）
２５補助筋
８０，８０’ 開口補強筋
８１，８１’ 補強部
８１ａ，８１ａ’ 環状部
８２，８３引掛部
Ｓ開口[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a structure that reinforces an opening formed through a structural member such as a horizontal member or a building structure or a civil engineering structure.
[0002]
[Prior art]
Reinforced concrete beams (horizontal members) are composed of a plurality of upper main bars, a plurality of lower main bars, a number of shear reinforcement bars surrounding the main bars and spaced apart in the extending direction of the main bars, And concrete embedding shear reinforcement. In order to pass an air conditioning equipment duct or the like through the beam, an opening may be formed in a direction perpendicular to the longitudinal direction of the beam.
[0003]
When the opening is formed, the strength of the beam, particularly the strength around the opening of the beam, is lowered, and damage such as cracking or peeling of the concrete may occur during an earthquake. Therefore, various opening reinforcement structures have been proposed conventionally. For example, as shown in FIG. 4A of Japanese Patent Laid-Open No. 6-146474, the opening is surrounded by a plurality of inclined reinforcing bars, or as shown in FIG. Trying to reinforce the opening.
[0004]
[Patent Document 1]
JP-A-6-146474 (FIGS. 1 and 4A)
[0005]
[Problems to be solved by the invention]
In the beam opening reinforcing structure of the above publication, the inclined reinforcing bars and ring bars do not have a force transmission relationship with the beam main bars. For this reason, there is a limit in preventing a decrease in shear strength due to the provision of the opening.
[0006]
[Means for Solving the Problems]
The first invention has been made to solve the above-mentioned problem, and a plurality of main bars extending linearly in the first direction and a plurality of shear reinforcements surrounding the main bars and arranged at intervals in the first direction. In a structural material of a building civil engineering structure, comprising a line, concrete embedding these main bars and shear reinforcement bars, and an opening reinforcing structure that reinforces an opening formed in a second direction orthogonal to the first direction, The opening reinforcing structure includes first and second opening reinforcing bars, and the first and second opening reinforcing bars include a substantially U-shaped reinforcing part, and a hook part connected to both ends of the reinforcing part. The hook portion of the first opening reinforcing bar is hooked to the main bar arranged on one side in the third direction orthogonal to the first and second directions, and the hook portion of the second opening reinforcing bar is the first hook It is hung on the main bar on the other side in the three directions, and the first and second opening reinforcing bars are complemented. Parts, characterized in that the enclosing portions at least substantially half the circumference of the opening. See the embodiment of FIGS.
[0007]
According to the above configuration, the opening is surrounded by the U-shaped reinforcing portion of the first and second opening reinforcing bars. In addition, these opening reinforcement bars are hung on the main bars by the hooks, and the force transmission path to the main bars is secured, so that the shear force generated around the opening of the component material is finally handled by the main bars. Can do. As a result, damage to the concrete around the opening can be significantly reduced. Further, these opening reinforcing bars can have a relatively simple configuration and can be easily installed.
[0008]
According to a second aspect of the present invention, in the structural material for a building civil engineering structure, the opening reinforcing structure includes an opening reinforcing bar, and the opening reinforcing bar is a main reinforcing bar on one side in a third direction orthogonal to the first and second directions. A reinforcing portion that extends from the main bar on the other side and a hooking portion that is connected to both ends of the reinforcing portion, the hooking portions being respectively hooked on the main bar on the one side and the main bar on the other side, The part is formed with an annular part wound around the opening. See the embodiment of FIGS.
In this configuration, the annular portion of the opening reinforcing bar surrounds the opening. In addition, since the hook portion of the opening reinforcing bar is hung on the opposing main bar and a force transmission path to the main bar is secured, damage to the concrete in the peripheral part of the opening can be remarkably reduced as in the first invention. Further, these opening reinforcing bars can have a relatively simple configuration and can be easily installed.
[0009]
In the third invention, a plurality of upper main bars, a plurality of lower main bars, a plurality of shear reinforcement bars surrounding the main bars and arranged at intervals in the extending direction of the main bars, and the main bars and the shear reinforcement bars are embedded. In the structural material of a building and civil engineering structure comprising concrete and an opening reinforcing structure that reinforces an opening formed in a direction perpendicular to the extending direction of the main reinforcement,
The opening reinforcing structure includes first and second opening reinforcing bars, and the first opening reinforcing bar is connected to a reinforcing portion that hangs down in a substantially U shape and a pair of upper ends of the reinforcing portion and is hung on the upper main reinforcing bar. The second opening reinforcing bar has a reinforcing part that rises in a substantially U shape, and a hooking part that is connected to a pair of lower ends of the reinforcing part and is hooked on the lower main bar, The reinforcing portion of the first opening reinforcing bar surrounds at least approximately the lower half of the opening, and the reinforcing portion of the second opening reinforcing bar surrounds at least the lower half of the opening. And See the embodiment of FIGS.
In the third aspect of the invention, the first aspect of the invention is limited to the horizontal member, and the same working effect as that of the first aspect of the invention is obtained.
[0010]
As an aspect of the third aspect of the invention, each of the first and second opening reinforcing bars is formed of a single continuous reinforcing bar, has a pair of the reinforcing portions, and extends at least in the penetrating direction of the opening. It has one straight portion, and this straight portion is provided as a common hooking portion connected to one end of the pair of reinforcing portions, and two intersections between the straight portion and the pair of reinforcing portions are two. It is hung on each main line. See the embodiment of FIGS.
According to this structure, a pair of reinforcement part can be installed by one operation | work, and installation work becomes still easier. In addition, since at least one end of the pair of reinforcing portions is connected by one straight portion, and this straight portion is hung on a plurality of main bars, it is possible to further ensure the transmission of force from the reinforcing portion to the main bars. it can.
[0011]
Each of the first and second opening reinforcing bars is provided with a pair of straight portions separated in the extending direction of the main bar, and is formed in a closed loop by welding both ends of the reinforcing bar. Also good. See the embodiment of FIGS.
According to this configuration, the opening reinforcing bars form a closed loop, and the two straight portions are hooked on the plurality of main bars, so that the configuration is simplified, the installation work is facilitated, and the reinforcing parts are moved to the main bars. The transmission of the power of can be maximized.
[0012]
Both ends of the reinforcing bar may constitute a part of the hooking part, and may be bent and hung on the main bar. See FIG. According to this structure, welding of a reinforcing bar becomes unnecessary.
Preferably, four or more upper main reinforcing bars and lower main reinforcing bars are arranged, a plurality of the first and second opening reinforcing bars are provided, and the reinforcing portions of the plurality of first opening reinforcing bars are in the penetration direction of the openings. The reinforcing portions of the plurality of second opening reinforcing bars are arranged so as to overlap the reinforcing portions of the first opening reinforcing bars, respectively. See the embodiment shown in FIGS. According to this configuration, each of the first and second opening reinforcing bars has four or more reinforcing portions and surrounds the opening, so that the reinforcing effect can be increased.
[0013]
As another aspect of the third invention, a plurality of the first and second opening reinforcing bars are provided, and each of the opening reinforcing bars is formed by a single continuous reinforcing bar having a single reinforcing portion. The reinforcing portions of the first opening reinforcing bars and the reinforcing portions of the second opening reinforcing bars are separated from each other in the penetration direction of the opening. See the embodiment shown in FIG. According to this configuration, the configuration of the opening reinforcing bar can be further simplified.
In each of the first and second opening reinforcing bars, both ends of the reinforcing portion may be bent and provided as a pair of hook portions, and the pair of hook portions may be hooked on a common main bar. See the embodiment shown in FIG. According to this configuration, the configuration of the opening reinforcing bar can be simplified to the maximum.
Each of the first and second opening reinforcing bars has a pair of hooking portions that extend linearly from both ends of the reinforcing portion in the penetrating direction of the opening, and an intersection between the pair of hooking portions and the reinforcing portion. May be hung on one common main bar, and the front end of the hook may be bent and hung on another common main bar. See the embodiment shown in FIGS. According to this configuration, since the hooking portion is hung on the plurality of main bars, the opening reinforcing bars can be stably installed.
[0014]
As another embodiment of the third invention, four upper main bars and four lower main bars are arranged, and the first and second opening reinforcing bars are provided one by one, and these first and second opening reinforcing bars are provided. Each of which is formed by one continuous reinforcing bar, and has four reinforcing parts and a linear hook part connected to the reinforcing part by bending the reinforcing bar, and the reinforcing part in the first opening reinforcing bar And the hooking portion are respectively hung on the upper four main bars, and the crossing portion of the second opening reinforcing bar between the reinforcing portion and the hooking portion is hung on the lower four main bars. See the embodiment shown in FIG.
According to this configuration, the installation work of the first and second opening reinforcing bars can be performed only once, so that the installation work can be simplified to the maximum. Moreover, since it is hung on four main muscles, the transmission of the force to a main muscle can also be exhibited to the maximum.
[0015]
As another aspect of the third invention, the reinforcing portions of the first and second opening reinforcing bars are formed so as to bend a straight line at a plurality of locations, and in each of the first and second opening reinforcing bars, The corresponding bent portions of the plurality of reinforcing portions are in positions that coincide with each other when viewed from the through direction of the opening, and the auxiliary bars extending in the through direction of the opening are arranged on the inner side so as to substantially contact the bent portion. Yes. See the embodiment shown in FIGS. According to this configuration, since the auxiliary muscle is structured along the opening, the opening reinforcing effect can be increased.
[0016]
According to a fourth aspect of the present invention, in the horizontal member of the building civil engineering structure, the opening reinforcing structure includes an opening reinforcing bar, the opening reinforcing bar includes a reinforcing part extending from the upper main bar to the lower main bar, and an upper end of the reinforcing part. A first hook portion that is connected to the upper main bar and a second hook portion that is connected to the lower end of the reinforcing portion and is hooked to the lower main bar, and the central portion of the reinforcing portion surrounds the opening. An annular portion wound around is formed. See the embodiment shown in FIGS.
In the fourth aspect of the invention, the second aspect of the invention is limited to the horizontal member, and the same working effect as that of the second aspect of the invention can be obtained.
[0017]
In a fourth aspect of the invention, the opening reinforcing bar is composed of one continuous reinforcing bar, and has a pair of reinforcing parts separated in the penetrating direction of the opening, and at least one linear part, and the linear part is It extends horizontally in the penetrating direction of the opening and is provided as a common hooking portion connected to one end of a pair of reinforcing portions, and the intersection of the straight portion and the pair of reinforcing portions is hung on two main bars. . See the embodiment shown in FIGS.
According to this structure, a pair of reinforcement part can be installed by one operation | work, and the installation operation | work of an opening reinforcement becomes much easier. In addition, since at least one end of the pair of reinforcing portions is connected by one straight portion, and this straight portion is hung on a plurality of main bars, it is possible to further ensure the transmission of force from the reinforcing portion to the main bars. it can.
[0018]
Preferably, the opening reinforcing bar is formed in a substantially rectangular shape having a pair of linear portions and a pair of reinforcing portions by welding both ends of the reinforcing bar. See the embodiment shown in FIGS. Thereby, an opening reinforcement can also play the role substantially equivalent to a shear reinforcement.
Preferably, a pair of the opening reinforcing bars are arranged apart from each other in the extending direction of the main reinforcing bars, and the annular portions of the pair of opening reinforcing bars are located at the same position as viewed from the penetrating direction of the opening and surround the opening. See the embodiment shown in FIGS. Accordingly, the opening reinforcing bars can be densely arranged around the opening instead of the shear reinforcing bars. In addition, the number of annular portions surrounding the opening can be increased.
[0019]
Preferably, the opening reinforcing structure further includes a pipe disposed in a direction orthogonal to the extending direction of the main bars, and an internal space of the pipe is provided as the opening. See the embodiment shown in all figures. By this pipe, it is possible to transmit the compressive force accompanying the shearing. In addition, since the concrete between the pipe and the main reinforcement can be effectively restrained, the reinforcing effect around the opening can be further enhanced, and the concrete can be prevented from peeling off from the inner peripheral surface of the opening.
More preferably, the outer periphery of the pipe is formed with irregularities for enhancing adhesion with concrete. Thereby, the further reinforcement effect is acquired.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. 1-4 shows the beam 10 (horizontal material as a structural material of a building). The beam 10 includes four upper main bars 11 (one main bar in the third direction) and four lower main bars 12 (the other in the third direction) extending horizontally along the longitudinal direction (first direction) of the beam 10. Side main bars) and a number of shear reinforcement bars 13 (stirrups) surrounding the main bars 11 and 12 and forming a vertically long rectangle. The four upper main bars 11 are arranged in parallel on a common plane, and the four lower main bars 12 are also arranged in parallel on another common plane. The shear reinforcement bars 13 are arranged at regular intervals in the longitudinal direction of the beam 10 (the extending direction of the main bars 11 and 12). The four corners of the shear reinforcing bar 13 are hung on the upper main bar 11 at the left and right ends and the lower main bar 12 at the lower left and right ends, and are connected to the main bars 11 and 12 by a wire (thin metal line) and positioned. . These main reinforcing bars 11 and 12 and the shear reinforcing bar 13 are embedded in concrete 14 (shown only in FIG. 6C).
[0021]
The shear reinforcement 13 is not disposed in the opening forming region X of the beam 10. In this embodiment, two shear reinforcement bars 13 are missing. As shown in FIGS. 4, 5 C, and 6 C, an opening H is formed in the opening forming region X, and an opening reinforcing structure 20 is provided. The opening reinforcing structure 20 includes two upper first opening reinforcing bars 21, two lower second opening reinforcing bars 22, and a steel pipe (pipe) 23.
[0022]
As best shown in FIG. 7B, the first opening reinforcing bar 21 includes a pair of U-shaped reinforcing portions 21a, and a linear portion 21b that connects one end of the pair of reinforcing portions 21a. And a straight line portion 21b connecting the other ends of the pair of reinforcing portions 21a to form a closed loop. The straight portion 21b is provided as a common hooking portion for the pair of reinforcing portions 21a. As shown in FIGS. 5C and 7B, the reinforcing portion 21a includes a pair of straight vertical portions 21x connected to the reinforcing portion 21a and a semicircular arc-shaped curved portion 21y connecting the lower ends of the vertical portions 21x. It consists of. The intersecting portion 21z between the reinforcing portion 21a and the straight portion 21b is curved with a radius of curvature corresponding to the outer periphery of the main muscle 11.
[0023]
The second opening reinforcing bar 22 has the same shape as the first opening reinforcing bar 21, and has a pair of reinforcing portions 22a and a pair of linear portions 22b (a common hooking portion). The reinforcing part 22a is composed of a pair of vertical parts 21x and a curved part 21y (shown with reference numerals only in FIG. 5C), and the intersecting part 22z between the reinforcing part 22a and the linear part 22b is curved.
[0024]
The opening reinforcing bars 21 and 22 are each formed by one continuous reinforcing bar. First, one continuous reinforcing bar is bent to make a frame 50 as shown in FIG. The frame 50 has a pair of long sides 51 and a pair of short sides 52 and is rectangular. Both ends of the rebar are butted together and welded. The welded portion 55 is located, for example, in the center (intermediate portion) of one short side portion 52 of the frame body 50. Next, as shown by an arrow in FIG. 7A, the rectangular frame 50 is formed in an arc shape at the center of the pair of long sides 51 so that the pair of short sides 52 of the frame 50 approaches. Bend. The curved long side portion 51 becomes the reinforcing portions 21 a and 22 a of the opening reinforcing bars 21 and 22, and the short side portion 52 becomes the straight portions 21 b and 22 b of the opening reinforcing bar 21 as they are.
[0025]
As shown in FIGS. 4, 5 C, and 6 C, the straight portion 21 b of the first opening reinforcing bar 21 extends horizontally in a direction perpendicular to the upper main bar 11 and is hung on the upper side of the main bar 11. And the reinforcement part 21a hangs down on the vertical plane orthogonal to the penetration direction (2nd direction) of the steel pipe 23 mentioned later. More specifically, the pair of straight portions 21b of the first opening reinforcing bar 21 are separated from each other in the extending direction of the main reinforcing bar 11, and the first to third of the upper main reinforcing bars 11 from the first to the third from the left. It is hung on the main muscle 11, and its intersection 21z is hung on the left main muscle 11 and the third main muscle 11. The pair of straight portions 21b of the other first opening reinforcing bar 21 are also separated from each other and are hung on the second to fourth main bars 11 from the left, and the intersection 21z is the fourth main bar 11 and the fourth main bar 11. It is hung on the main muscle 11. The straight portions 21b of the two first opening reinforcing bars 21 partially overlap. The pair of reinforcing portions 21 a of the two first opening reinforcing bars 21, that is, the four reinforcing portions 21 a are separated from each other and hang down from the different main reinforcing bars 11.
[0026]
Similarly, the straight portion 22 b of the second opening reinforcing bar 22 extends horizontally in a direction perpendicular to the lower main bar 12 and is hung on the lower side of the main bar 12. The reinforcing portion 22 a rises on a vertical plane orthogonal to the penetration direction of the steel pipe 23. The pair of straight portions 22b of the one second opening reinforcing bar 22 are separated from each other, and are hung on the three main bars 12 from the left to the third of the lower main bars 12, The intersection 22z hits the left main muscle 12 and the third main muscle 12. The straight line portions 22b of the other second opening reinforcing bars 22 are separated from each other and are hung on the second to fourth main bars 12 from the left, and the intersection 22z is formed between the second main bars 12 and the fourth main bars 12. It hits the main muscle 12. The pair of reinforcing portions 22 a of the two first opening reinforcing bars 22, that is, the four reinforcing portions 22 a are separated from each other and rise from different main reinforcing bars 12. The opening reinforcing bars 21 and 22 are connected to the main bars 11 and 12 by a wire for positioning.
[0027]
As best shown in FIG. 5C, the reinforcing portion 21a of the first opening reinforcing bar 21 and the reinforcing portion 22a of the second reinforcing bar 22 are in a direction perpendicular to the plane of the drawing (the extending direction of the beam 10). It intersects perpendicularly and sees from the horizontal direction. Further, as shown in FIG. 6C, the reinforcing portion 21a of the first opening reinforcing bar 21 and the reinforcing portion 22a of the second reinforcing bar corresponding thereto overlap. A steel pipe 23 is inserted into an annular space formed by the reinforcing portions 21a and 22a. The internal space of the steel pipe 23 is provided as the opening S. Each reinforcement part 21a, 22a surrounds the steel pipe 23 (opening S) half by half.
[0028]
Next, the manufacturing process of the opening reinforcing structure 20 will be described. As shown in FIG. 1, FIG. 2, FIG. 5 (A), FIG. 6 (A), (B), the linear portion 21b of one first opening reinforcing bar 21 is placed on the upper three main bars 11, The pair of reinforcing portions 21a are arranged so as to hang down, and the straight portions 21b of the other first opening reinforcing bars 21 are placed on the upper three main reinforcing bars 11, and the pair of reinforcing portions 21a are arranged so as to hang down. Then, these straight portions 21b are connected to the main muscle 11 with a number line.
In the same manner as described above, the second opening reinforcing bar 22 is attached to the lower main bar 12 as shown in FIGS. 2, 3, 5 (B), 6 (B), and (C). The order of attaching these four opening reinforcing bars 21 and 22 is not particularly limited.
Next, as shown in FIGS. 4, 5 C, and 6 C, the steel pipe 23 is inserted into the annular space formed by the intersection of the reinforcing portions 21 a and 22 a of the opening reinforcing bars 21 and 22. Finally, concrete 14 is placed.
[0029]
A duct or the like of an air conditioning facility is inserted into the opening S of the beam 10. Since the concrete 14 around the opening S is reinforced by the opening reinforcing bars 21 and 22, it is possible to remarkably reduce cracks and the like during an earthquake. That is, when a large shearing force is applied to the beam 10, it is handled by the reinforcing portions 21a and 22a of the opening reinforcing bars 21 and 22 surrounding the opening S, and the main bars 21 and 22 on which the straight portions 21b and 22b are hung. This is because the main muscles 21 and 22 can finally handle the shearing force. The steel pipe 23 can transmit a compressive force accompanying shearing. Moreover, since the concrete 14 between the steel pipe 23 and the main reinforcing bars 11 and 12 can be effectively restrained, the concrete 14 serves to reinforce the peripheral portion of the opening S of the concrete 14 and prevents the concrete near the opening S from being peeled off. To play a role.
On the outer periphery of the steel pipe 23, irregularities are formed over the entire area in order to improve the adhesion with the concrete 14, and a further reinforcing effect is obtained. The unevenness is hardened by, for example, a large number of vertical ribs extending in the axial direction of the steel pipe 23 and horizontal ribs extending in the circumferential direction.
[0030]
In this embodiment, the opening reinforcing bars 21 and 22 formed by one continuous reinforcing bar have a simple configuration. Since the opening reinforcing bars 21 and 22 can be installed so as to be hung on the main bars 11 and 12, the installation work is simple. In addition, positioning is simple by hanging the intersecting portions 21z and 22z on the main muscles 11 and 12.
[0031]
The present invention is not limited to the first embodiment, and various forms can be adopted. For example, as shown in FIG. 5C, auxiliary bars 29 made of short reinforcing bars may be arranged above and below the steel pipe 23 in parallel with the main bars 11 and 12.
The straight portions 21b and 22b of the opening reinforcing bars 21 and 22 may be shortened from the first embodiment and hung on the adjacent two main bars 11 and 12. For example, one first opening reinforcing bar 21 is hung on the first and second main bars 11 from the left, and the other first reinforcing bar 21 is hung on the third and fourth main bars 11 from the left. Similarly, the two opening reinforcing bars 22 are also hung on the main bars 12.
[0032]
Next, another embodiment of the present invention will be described with reference to the drawings. In these embodiments, components corresponding to the preceding embodiments are assigned the same reference numerals and detailed description thereof is omitted.
In the embodiment shown in FIGS. 8 and 9, the opening reinforcing bar is formed by one continuous reinforcing bar as in the first embodiment, but both ends thereof are bent without being welded. In these embodiments, the second opening reinforcing bar has the same shape as the first reinforcing bar, and the description thereof will be omitted.
[0033]
In the first opening reinforcing bar 21A of the embodiment shown in FIG. 8A, one linear portion 21b functions as a common hooking portion by connecting one end of the pair of reinforcing portions 21a as in the first embodiment. The other straight portion 21 b ′ serves only as a hooking portion for the other end of the one reinforcing portion 21 a and is hung on the three main bars 11. The other end of the other reinforcing portion 21a is bent to form a hooking portion 21c. The hook portion 21c and the bent portion 21d formed at the tip portion of the straight portion 21b ′ are hung on the common main bar 11.
[0034]
In the first opening reinforcing bar 21B of the embodiment shown in FIG. 8B, one linear portion 21b functions as a common hooking portion by connecting one ends of the pair of reinforcing portions 21a in the same manner as in the first embodiment. The other ends of the pair of reinforcing portions 21a are connected to straight portions 21b "as hook portions. These two straight portions 21b" are half the length of the first embodiment, and each of the two straight portions 21b " A bent portion 21e formed on the main muscle 11 and formed at the tip thereof is hooked on the central main muscle 11.
[0035]
In the first opening reinforcing bar 21C of the embodiment shown in FIG. 8C, one linear portion 21b functions as a common hooking portion by connecting one end of the pair of reinforcing portions 21a in the same manner as in the first embodiment. A bent portion 21f (hook portion) is formed at the other end of the pair of reinforcing portions 21a. These bent portions 21f are hung on the main streaks 11 common to the corresponding intersecting portions 21z.
[0036]
In the embodiment shown in FIG. 8A, the straight portions 21b and 21b ′ may be approximately half the length and hung on the two main bars 11. Similarly, in FIGS. 8B and 8C, the straight portion 21b may be shortened and hung on the two main bars 11.
[0037]
The first opening reinforcing bar 21D of the embodiment of FIG. 8D is similar to the embodiment of FIG. 8B, but the straight portion 21b is lengthened to be hung on the four main bars 11. The two straight portions 21b ″ are hung on two different main muscles 11, respectively.
The first opening reinforcing bar 21E of the embodiment of FIG. 8E is also similar to the embodiment of FIG. 8B, but the straight portion 21b is lengthened to be hung on the four main bars 11. The two straight portions 21 b ″ are also long and are hung on the three main bars 11.
[0038]
In the embodiment shown in FIGS. 9A to 9C, the opening reinforcing bar has a single reinforcing portion. In this embodiment, a plurality of, for example, two first opening reinforcing bars and two second opening reinforcing bars are arranged. The first opening reinforcing bar 21F shown in FIG. 9A has a reinforcing portion 21a and a linear portion 21g (hooking portion) extending from both ends of the reinforcing portion 21a. The straight portion 21g is hung on the three main bars 11, and the bent portion 21h at the tip is hung on the intermediate main bar 11.
The first opening reinforcing bar 21G shown in FIG. 9B has a straight portion 21g shorter than the first opening reinforcing bar 20A of FIG.
The first opening reinforcing bar 21H shown in FIG. 9C does not have the straight portion 20g shown in FIGS. 9A and 9B, and has bent portions 21h (hook portions) formed at both ends of the reinforcing portion 21a. Yes.
[0039]
In the embodiment shown in FIG. 10, a rectangular frame 60 is formed by first bending a single reinforcing bar like a single stroke and welding both ends thereof. The frame 60 includes a pair of long side portions 61, a pair of middle bone portions 62 that are parallel to the long side portions 61 and disposed inside thereof, and a pair of orthogonal portions that are orthogonal to the long side portions 61 and the middle bone portions 62. And a short side portion 63. The long side portion 61 and the middle bone portion 62 are substantially equally spaced. One short side portion 63 includes a long straight portion 63a that connects one end of the pair of long side portions 61 and a short straight portion 63b that connects one end of the pair of middle bone portions 62. The straight portion 63b is a straight line. It overlaps at the center of the part 63a. The other short side portion 63 includes a straight portion 63c that connects the other end of one long side portion 61 and the other end of one middle bone portion 62, and the other end of the other long side portion 61 and the other middle bone portion. 62, and the straight portions 63 c and 63 d overlap at the center of the short side portion 63. Both ends of the rebar are butted together and welded. The welded portion 65 is located at an intermediate portion of the straight portion 63d that is one of the straight portions of the short side portion 63 of the frame 60, for example.
[0040]
Next, as shown by the arrows in FIG. 10, the central portions of the long side portion 61 and the middle bone portion 62 are curved in an arc shape so that the pair of short side portions 63 approach each other. Thereby, the curved long side part 61 and the middle bone part 62 become a reinforcement part of an opening reinforcement. Further, the straight portions 63a and 63b and the straight portions 63c and 63d constituting the short side portion 63 become the straight portions (hooking portions) of the opening reinforcing bars 21 as they are. The overall shape is similar to the shape in which the two opening reinforcing bars 21 of the first embodiment are integrated (see FIG. 1). The intersecting portions of the straight portions 63a to 63d, the long side portion 61, and the middle bone portion 62 are curved and are hung on the four main muscles 11, respectively.
[0041]
The opening reinforcing structure 20J of the embodiment shown in FIG. 11 includes a first opening reinforcing bar 21J, a second opening reinforcing bar 22J, a steel pipe 23, and an auxiliary bar 25 made of a linear reinforcing bar that is almost the same length as or slightly shorter than the steel pipe 23. And have. These opening reinforcing bars 21J and 22J have the same basic configuration as the opening reinforcing bars 21 and 22 of the first embodiment, and are arranged two by two. Only the shapes of the reinforcing portions 21a 'and 22a' of the opening reinforcing bars 21J and 22J are different from those of the first embodiment. The pair of reinforcing portions 21a ′ of the first opening reinforcing bars 21J are substantially U-shaped, but are formed symmetrically so that a straight line is bent at two places (a plurality of places), and the bent portions of the pair of reinforcing parts 21a 21p and bending parts 21q are in the position which matched when seeing from the penetration direction of the said opening S. The auxiliary muscle 25 extends in the penetrating direction of the opening S, is arranged on the inner side so as to be substantially in contact with the bent portions 21p and 21q, and is bound by a wire.
[0042]
Similarly, the reinforcing portion 22a ′ of the second opening reinforcing bar 22J has bent portions 22p and 22q, and the auxiliary bar 25 is disposed here. In this embodiment, the strength around the opening S can be further improved by arranging the four auxiliary muscles 25.
[0043]
In the opening reinforcing structure 20K of the embodiment shown in FIG. 12, the first opening reinforcing bar 21K has a substantially U-shaped left-right symmetrical reinforcing portion 21a ″ having bent portions 21r, 21s, and 21t at three locations. Similarly, the reinforcing portion 22a ″ of the second opening reinforcing bar 22K also has the bent portions 22r, 22s, and 22t at three locations, but the other points are the same as in the embodiment of FIG. The bent portions 21r and 22r of the opening reinforcing bars 21K and 22K coincide with each other when viewed from the direction of penetration of the opening S, and a common reinforcing bar 25 is disposed so as to contact the inside thereof. Similarly, the bent portions 21t and 22t of the opening reinforcing bars 21K and 22K also coincide with each other when viewed from the direction of penetration of the opening S, and a common reinforcing bar 25 is disposed so as to contact the inside thereof. Note that the bent portions 21s of the pair of reinforcing portions 21a "of the first opening reinforcing bar 21K and the bent portions 22s of the pair of reinforcing portions 22a" of the second opening reinforcing bar 22K also coincide with each other when viewed from the penetration direction of the opening S. The auxiliary muscle 25 is arranged inside thereof.
[0044]
The shape of the reinforcing portion and the arrangement of the auxiliary bars shown in FIGS. 11 and 12 can be adopted in all the embodiments described before.
Moreover, in all the embodiments described above, the distal end portions of the reinforcing portions of the first and second opening reinforcing bars may form an annular shape so as to surround each opening approximately one and a half times. Also in this case, the reinforcing portion is generally U-shaped.
[0045]
Next, the embodiment of FIG. 13 will be described. In this embodiment, as shown in FIG. 13B, the opening reinforcing bar 80 includes a pair of reinforcing parts 81 extending vertically from the upper main bar 11 to the lower main bar 12, and the upper main bar 11 connected to the upper ends of these reinforcing parts 81. A first hooking portion 82 that extends linearly in a straight line so as to be orthogonal to the second hooking portion 83 and a second hooking portion 83 that extends to the lower end of the reinforcing portion 81 and extends horizontally so as to be orthogonal to the lower main reinforcement 12. It is formed in a rectangular shape. A circular annular portion 81 a is formed at a substantially central portion of the reinforcing portion 81.
[0046]
The opening reinforcing bar 80 is formed by one continuous reinforcing bar. First, the reinforcing bars are bent to make a frame 90 as shown in FIG. The frame 90 has a pair of long side portions 91 and a pair of short side portions 92, and has a rectangular shape. Both ends of the rebar are butted together and welded. The welded portion 95 is located at the center (intermediate portion) of one short side portion 92 of the frame 90, for example. Next, the long side portion 91 of the frame body 90 is bent so as to make one turn at the central portion. The pair of bent long side portions 91 become the reinforcing portions 81 of the opening reinforcing bars 80, and the pair of short side portions 92 become the first and second hooking portions 82 and 83 of the opening reinforcing bars 80 as they are. Note that the welded portion 95 may be positioned at the straight portion of the reinforcing portion 81.
[0047]
As shown in FIG. 13A, the opening reinforcing bars 80 are arranged so as to surround all the main reinforcing bars 11 and 12 like the shear reinforcing bars, and the four intersecting portions 84 of the reinforcing portion 81 and the hooking portions 82 and 83 are arranged. Is hung on the upper main muscle 11 and the lower main muscle 12. In the present embodiment, two opening reinforcing bars 80 having the above shape are used as shown in FIG. These two opening reinforcing bars 80 make the annular portion 81a face each other. As shown in FIG. 13 (D), the two opening reinforcing bars 80 are arranged at substantially equal intervals to the shear reinforcing bars, and the annular portion 81a of the two opening reinforcing bars 80 is viewed from the penetration direction of the steel pipe 23 described later. Match. In this state, the opening reinforcing bars 80 are tied to the main bars 11 and 12 with a wire, and finally the steel pipe 23 is passed through the four annular portions 81a, and then concrete is placed.
[0048]
The opening reinforcing bar 80 ′ shown in the embodiment shown in FIG. 14 is similar to the embodiment shown in FIG. The only difference is that the reinforcing portion 81 ′ is bent in a square shape and the annular portion 81a ′ is a quadrangle. The other components are given the same numbers, and the description thereof is omitted. Also in the present embodiment, the annular portions 81a ′ of the two opening reinforcing bars 80 ′ are arranged to coincide with each other.
[0049]
In all the embodiments described above, a pipe made of another material such as a vinyl chloride pipe may be used instead of the steel pipe, or the pipe may be omitted. When the pipe is omitted, it is a matter of course that a sufficient concrete cover thickness is taken between the reinforcing bar and the inner periphery of the opening.
The present invention can also be applied to components such as horizontal members in civil engineering structures.
[0050]
【The invention's effect】
As described above, according to the present invention, it is possible to remarkably reduce damages such as cracks in concrete in openings surrounding portions of structural members of building civil engineering structures, such as horizontal members, using an opening reinforcing structure having a simple structure. Can do. Also, the installation work of the opening reinforcing structure is easy.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a state immediately before a first stage is started in an assembly process of an opening reinforcing structure for a beam according to a first embodiment of the present invention.
FIG. 2 is a perspective view showing a state immediately before the first stage is completed and the second stage is started in the assembly process;
FIG. 3 is a perspective view showing a state in which the second stage is completed in the assembly process.
FIG. 4 is a perspective view showing a state where a third stage is completed in the assembly process.
FIGS. 5A and 5B are side views showing the assembly process of the opening reinforcing structure step by step, in which FIG. 5A shows a state in which the first stage of the assembly process is completed, and FIG. 5B shows a second stage of the assembly process; (C) shows a state in which the third stage of the assembly process is completed.
6A and 6B are longitudinal sectional views showing the assembly process of the opening reinforcing structure in order, wherein FIG. 6A shows a state immediately before the first stage is started, and FIG. 6B shows the state after the first stage is completed. The state immediately before the start of the second stage is shown, and (C) shows the state where the second stage and the third stage are completed.
FIG. 7 is a perspective view showing a method for manufacturing an opening reinforcing bar used in the opening reinforcing structure, wherein FIG. 7A shows a frame obtained by bending one reinforcing bar, and FIG. The opening reinforcing bar finally obtained by bending the frame is shown.
FIGS. 8A to 8E are perspective views showing other embodiments of an opening reinforcing bar of a type having a pair of reinforcing portions as in the first embodiment.
FIGS. 9A to 9C are perspective views showing opening reinforcing bars of a type having a single reinforcing portion, respectively.
FIG. 10 is a perspective view showing a frame body in a state before final processing of an opening reinforcing bar according to still another embodiment of the present invention.
FIG. 11 is a side view showing an opening reinforcing structure according to still another embodiment of the present invention.
FIG. 12 is a side view showing an opening reinforcing structure according to still another embodiment of the present invention.
FIG. 13 is a perspective view showing a frame body in a state before the final processing of the opening reinforcing bars, showing an opening reinforcing bar of the type spanned between the upper and lower beam main reinforcing bars, and (B). Is a perspective view showing the same opening reinforcing bar, (C) is a side view showing a state in which a pair of the opening reinforcing bars are prepared and passed through the beam main bar, and (D) is a reinforcing portion of the pair of opening reinforcing bars. It is a side view which shows the state which positioned so that may be matched and the steel pipe was inserted.
FIG. 14 is a side view showing another example of the opening reinforcing bar of the type spanned between the upper and lower beam main bars, and (A) is a side view showing a state in which a pair of the opening reinforcing bars are prepared and passed through the beam main bars. (B) is a side view showing a state in which the reinforcing portions of the pair of opening reinforcing bars are positioned so as to coincide with each other.
[Explanation of symbols]
10 beams (components of buildings, horizontal members)
11 Upper principal muscle
12 Lower main muscle
13 Shear reinforcement
14 Concrete
20, 20J, 20K Opening fixing structure
21, 21A-21K 1st opening reinforcement
22, 22A-22K 2nd opening reinforcement
21a, 21a ', 21a ", 22a, 22a', 22a" reinforcement part
21b, 21b ', 22b Straight line part (hook part)
21f Bent part (hook part)
21z intersection
21p, 21q, 21r, 21s, 21t Bending part
23 Steel pipe (pipe)
25 Auxiliary muscle
80,80 'opening reinforcement
81, 81 'reinforcement
81a, 81a 'annular part
82, 83 hook part
S opening

Claims

A plurality of main bars extending linearly in the first direction, a number of shear reinforcement bars surrounding the main bars and spaced in the first direction, concrete embedding these main bars and shear reinforcement bars, and the first direction An opening reinforcing structure that reinforces an opening formed through in a second direction orthogonal to the structural member of the building civil engineering structure,
The opening reinforcing structure includes first and second opening reinforcing bars, and the first and second opening reinforcing bars include a substantially U-shaped reinforcing part, and a hook part connected to both ends of the reinforcing part. The hook portion of the first opening reinforcing bar is hooked to the main bar arranged on one side in the third direction orthogonal to the first and second directions, and the hook portion of the second opening reinforcing bar is the first hook A structural material for a civil engineering structure, which is hung on a main bar on the other side in three directions, and the reinforcing portions of the first and second opening reinforcing bars surround at least approximately half the circumference of the opening.

A plurality of main bars extending linearly in the first direction, a number of shear reinforcement bars surrounding the main bars and spaced in the first direction, concrete embedding these main bars and shear reinforcement bars, and the first direction An opening reinforcing structure that reinforces an opening formed through in a second direction orthogonal to the structural member of the building civil engineering structure,
The opening reinforcing structure includes an opening reinforcing bar, the opening reinforcing bar extending from one main bar to the other main bar in a third direction orthogonal to the first and second directions, and A hook part that is connected to both ends, these hook parts are respectively hooked on the main bar on the one side and the main bar on the other side, and a ring that is wound around the opening at a substantially central part of the reinforcing part A construction material for a civil engineering structure characterized in that a part is formed.

A plurality of upper main bars, a plurality of lower main bars, a number of shear reinforcement bars surrounding the main bars and spaced apart in the extension direction of the main bars, concrete embedding these main bars and shear reinforcement bars, and extension of the main bars In a horizontal member of an architectural civil structure having an opening reinforcing structure that reinforces an opening formed through in a direction perpendicular to the direction,
The opening reinforcing structure includes first and second opening reinforcing bars, and the first opening reinforcing bar is connected to a reinforcing portion that hangs down in a substantially U shape and a pair of upper ends of the reinforcing portion and is hung on the upper main reinforcing bar. The second opening reinforcing bar has a reinforcing part that rises in a substantially U shape, and a hooking part that is connected to a pair of lower ends of the reinforcing part and is hooked on the lower main bar, The reinforcing portion of the first opening reinforcing bar surrounds at least approximately the lower half of the opening, and the reinforcing portion of the second opening reinforcing bar surrounds at least the lower half of the opening. Horizontal material for architectural civil engineering structure.

Each of the first and second opening reinforcing bars is formed of a single continuous reinforcing bar, has a pair of the reinforcing portions, and has at least one linear portion extending in the penetration direction of the opening. A portion is provided as a common hooking portion connected to one end of the pair of reinforcing portions, and two intersections between the linear portion and the pair of reinforcing portions are respectively hung on two main bars. The horizontal member of the architectural civil engineering structure according to claim 3.

Each of the first and second opening reinforcing bars has a pair of straight portions separated in the extending direction of the main bars, and is formed in a closed loop by welding both ends of the reinforcing bars. The horizontal member for a building civil engineering structure according to claim 4.

The both ends of the said reinforcing bar constitute a part of the above-mentioned hook part, and are respectively bent and hung on the main reinforcement, The horizontal member of the construction civil engineering structure according to claim 4 characterized by things.

Four or more upper main bars and lower main bars are arranged, and a plurality of the first and second opening reinforcing bars are provided,
The reinforcing portions of the plurality of first opening reinforcing bars are arranged apart from each other in the penetrating direction of the opening, and the reinforcing portions of the plurality of second opening reinforcing bars overlap with the reinforcing portions of the first opening reinforcing bars, respectively. It is arrange | positioned, The horizontal member of the construction civil engineering structure in any one of Claims 4-6 characterized by the above-mentioned.

A plurality of the first and second opening reinforcing bars are provided, and each of the opening reinforcing bars is formed by a single continuous reinforcing bar having a single reinforcing portion, and the reinforcing portion of the first opening reinforcing bar. The horizontal members of the architectural civil engineering structure according to claim 3, wherein the reinforcing portions of the second opening reinforcing bars are separated from each other in the direction of penetration of the opening.

In each of the first and second opening reinforcing bars, both ends of the reinforcing part are bent and provided as a pair of hook parts, and the pair of hook parts are hung on a common main bar. A horizontal member for an architectural civil structure according to claim 8.

Each of the first and second opening reinforcing bars has a pair of hooking portions that extend linearly from both ends of the reinforcing portion in the penetrating direction of the opening, and an intersection between the pair of hooking portions and the reinforcing portion. 9. The horizontal member of the construction civil engineering structure according to claim 8, wherein the hook is hung on one common main bar, and the tip of the hook part is bent and hung on another common main bar.

Four upper main bars and four lower main bars are arranged, and the first and second opening reinforcing bars are provided one by one,
Each of the first and second opening reinforcing bars is formed by one continuous reinforcing bar, and has four reinforcing parts and a linear hook part connected to the reinforcing part by bending the reinforcing bar. ,
The intersections of the reinforcing portion and the hooking portion in the first opening reinforcing bar are respectively hung on the upper four main bars, and the intersections of the reinforcing portion and the hooking portion in the second opening reinforcing bar are the lower four main bars. The horizontal member of the architectural civil engineering structure according to claim 3, wherein the horizontal member is hung on each of the two.

The reinforcing portions of the first and second opening reinforcing bars are formed so as to bend the straight line at a plurality of locations, and the corresponding bent portions of the plurality of reinforcing portions are respectively provided in the first and second opening reinforcing bars. The auxiliary muscles, which are in a position coincident with each other when viewed from the direction of penetration of the opening and extend in the direction of penetration of the opening, are arranged on the inner side so as to substantially contact the bent portion. The horizontal member of the construction civil engineering structure in any one of 11.

A plurality of upper main bars, a plurality of lower main bars, a number of shear reinforcement bars surrounding the main bars and spaced apart in the extension direction of the main bars, concrete embedding these main bars and shear reinforcement bars, and extension of the main bars In a horizontal member of an architectural civil structure having an opening reinforcing structure that reinforces an opening formed through in a direction perpendicular to the direction,
The opening reinforcing structure includes an opening reinforcing bar, and the opening reinforcing bar includes a reinforcing part extending from the upper main bar to the lower main bar, a first hook part that is connected to the upper end of the reinforcing part and is hung on the upper main bar, and the reinforcing part. And a second hook portion that is connected to the lower main bar and is hooked on the lower main bar, and an annular portion that is wound around the opening is formed at a substantially central portion of the reinforcing portion. Horizontal materials for building civil engineering structures.

The opening reinforcing bar is composed of one continuous reinforcing bar, and has a pair of reinforcing portions separated in the penetration direction of the opening and at least one straight portion, and the straight portion extends in the penetration direction of the opening. A horizontally extending portion is provided as a common hook portion connected to one end of a pair of reinforcing portions, and an intersection portion of the straight portion and the pair of reinforcing portions is hung on two main bars. Item 14. A horizontal member for an architectural civil structure according to item 13.

The building according to claim 14, wherein the opening reinforcing bar is formed in a substantially rectangular shape having a pair of linear portions and a pair of reinforcing portions by welding both ends of the reinforcing bar. Horizontal members for civil engineering structures.

A pair of the opening reinforcing bars are arranged apart from each other in the extending direction of the main reinforcing bars, and the annular portions of the pair of opening reinforcing bars are located at the same position as viewed from the penetrating direction of the opening and surround the opening. Item 16. A horizontal member for an architectural civil structure according to item 14 or 15.

The said opening reinforcement structure is further provided with the pipe arrange | positioned in the direction orthogonal to the extending direction of a main reinforcement, The internal space of this pipe is provided as said opening, The said opening is provided. Horizontal materials for building civil engineering structures.

The horizontal member of the architectural civil structure according to claim 17, wherein the outer periphery of the pipe is formed with irregularities for enhancing adhesion with concrete.