JP2004124369A

JP2004124369A - Beam column connection structure of circular steel pipe column

Info

Publication number: JP2004124369A
Application number: JP2002285648A
Authority: JP
Inventors: Takashi Morita; 森田　隆司; Fumihisa Yoshida; 吉田　文久
Original assignee: Daiwa House Industry Co Ltd
Current assignee: Daiwa House Industry Co Ltd
Priority date: 2002-09-30
Filing date: 2002-09-30
Publication date: 2004-04-22
Anticipated expiration: 2022-09-30
Also published as: JP3958175B2

Abstract

<P>PROBLEM TO BE SOLVED: To provide a beam column connection structure of a circular steel pipe column which is simple in structure, easy in working, and low in cost. <P>SOLUTION: The beam column connection structure is constructed by connecting a beam 2 to the circular steel pipe column 1 wherein the beam 2 is formed of an H beam having a width narrower than that of the column 1. A beam connection porion of the steel pipe column 1 is of a non-diaphragm structure. The beam 2 is connected to the steel pipe column 1 via joint plates 3 which are connected to upper and lower flanges 2a of the beam at beam end portions, respectively. The column joint edge of each joint plate 3 is expanded broader than a beam width, and has an arcuate contour conforming to the side surface of the steel pipe column 1. Thus the column joint edge is abutted against the side surface of the steel pipe column 1 and welded to the same. <P>COPYRIGHT: (C)2004,JPO

Description

【０００１】
【発明の属する技術分野】
この発明は、円形の鋼管柱に、鋼管柱よりも幅狭のＨ形鋼製の梁を接合したノンダイヤフラム形式の柱梁接合構造に関する。
【０００２】
【従来の技術と発明が解決しようとする課題】
従来、円形鋼管柱の柱梁接合構造として、図９に示すダイヤフラム形式のものが一般に採用されている。この従来例では、円形の鋼管柱２１の梁接合部に、予め工場で平面形状が八角形の上下２段のダイヤフラム２９，２９を溶接すると共に、これら上下２段のダイヤフラム２９，２９の各一辺と、両ダイヤフラム２９，２９間の鋼管柱２１の側面とに、Ｈ形鋼製のブラケット２８を溶接する。現場では、鋼管柱２１のブラケット２８に、添え板による梁継手２３Ａ，２３Ｂ，２３Ｃを介してＨ形鋼製の梁２２をボルト接合する。鋼管柱２１へのブラケット２８の溶接は、上下のダイヤフラム２９，２９の対応する各一辺にブラケット２８の上下フランジ２８ａの端部を、また鋼管柱２１の側面にブラケット２８のウェブ２８ｂの端部をそれぞれ突き合わせ溶接して行う。
【０００３】
しかし、このような柱梁接合構造では、工場での鋼管柱２１の加工工数が多くなり、しかも添え板の梁継手２３Ａ，２３Ｂ，２３Ｃも必要で、コストアップとなる。
【０００４】
他のダイヤフラム形式の例として、図１０に示すものも知られている。この従来例では、円形の鋼管柱２１の梁接合部に、予め工場で図９の従来例の場合と同様の上下２段のダイヤフラム２９，２９を溶接すると共に、これら両ダイヤフラム２９，２９の間の鋼管柱２１側面にガセットプレート２６を溶接する。現場では、梁２２のウェブ２２ｂの端部を鋼管柱２１のガセットプレート２６にボルト止めし、両ダイヤフラム２９，２９の対応する各一辺に梁２２の上下フランジ２２ａ，２２ａ端を突き合わせ溶接する。
【０００５】
この従来例の場合、ブラケットや、添え板形式の梁継手が不要であるが、ダイヤフラム形式であるため、工場での鋼管柱２１の加工工数が多くなる点は図９の従来例と同じである。
【０００６】
ノンダイヤフラム形式の従来例としては、図１１に示す増肉鋼管柱を用いたものがある。この従来例は、円形の鋼管柱２１の梁接合部を増肉部２１ａとして補強し、その鋼管柱２１の梁接合部に、予め工場でＨ形鋼製のブラケット２８Ａを溶接したものである。現場では、鋼管柱２１のブラッケット２８Ａに、添え板式の梁継手２３Ａ，２３Ｂ，２３Ｃを介して梁２２をボルト接合する。鋼管柱２１へのブラケット２８Ａの溶接は、ブラケット２８Ａの端部を図１２のように鋼管柱２１の外径に合わせて円弧状に開先加工して行う。
【０００７】
このように、ダイヤフラムを省略した場合は、梁２２（具体的にはブラケット２８Ａ）の端部を鋼管柱２１の外径に合わせて円弧状に加工しなければならない。また、このように端部をＲ加工された梁２２は、図１３のように、現場で既に建て込まれた鋼管柱２１の間に、側方から納めようとしても、Ｒ加工部分の端部が中央よりも出っ張っていて円形鋼管柱２１との干渉を生じるため、納めることができない。そのため、上述のように、予め工場で鋼管柱２１にブラケット２８Ａを溶接しておき、現場では梁２２を添え板式の梁継手２３Ａ，２３Ｂ，２３Ｃを介してボルト接合しなければならない。このようにブラケット２８Ａと添え板とを用いるため、やはりコストアップとなる。
また、ダイヤフラムを省略したこの従来例の場合、梁フランジ幅が狭いと、鋼管柱２１の面外変形耐力が小さいため、図１４のように梁端モーメントにより梁２２のフランジ２２ａに大きい引っ張り力Ｔが働いたときに、鋼管柱２１が変形することがある。
このため、梁２２における上下フランジ２２ａの先端部の幅をテーパ状に広げることを考えた。このように梁フランジ幅を変えることは、梁２２に、上下フランジ２２ａとウェブとを溶接組立したタイプのもの、いわゆるビルト型のＨ形鋼を用いることで可能である。しかし、このようなビルト型のＨ形鋼でフランジ幅をテーパ状に加工するには、加工が煩雑となり、コスト高の要因となる。
【０００８】
この発明の目的は、このような課題を解消し、構造が簡素で、堅固な接合が行え、かつ加工が容易で安価に構築できる円形鋼管柱の柱梁接合構造を提供することである。
【０００９】
【課題を解決するための手段】
この発明の円形鋼管柱の柱梁接合構造は、円形の鋼管柱に、この鋼管柱よりも幅狭のＨ形鋼製の梁を接合した柱梁接合構造において、上記鋼管柱の梁接合部がノンダイヤフラム構造であり、上記梁は、梁端部で上下のフランジにそれぞれ接合された接合プレートを介して上記鋼管柱に接合され、上記各接合プレートは柱接合端が梁幅よりも広がっていて、この柱接合端が鋼管柱の側面に沿う円弧形状であり、鋼管柱の側面に突合わせ溶接されたものである。接合プレートと梁との接合は、溶接であっても、ボルト接合であっても良い。梁の幅は、例えば円形鋼管柱の外周面の断面となる円に内接する正方形の１辺の幅と同程度か、またはこの１辺よりも狭い幅である。
この構成によると、梁の上下フランジを、接合プレートを介して鋼管柱に接合するようにしたため、円形鋼管柱の外周形状に沿わせる開先加工が、平板状の部材である接合プレートを円弧状に加工するだけで良く、従来のＨ形鋼の上下フランジに円弧状の加工を行うものに比べて加工が容易である。そのため、安価に構成できる。梁のフランジに発生する荷重は、接合プレートを介して鋼管柱に伝わる。この場合に、接合プレートは柱接合端が梁幅よりも広がっているため、広い範囲で鋼管柱と接合できて、鋼管柱の面外変形耐力も確保される。また、ノンダイヤフラム構造であり、しかも鋼管柱に梁端部となるブラケットが不要となるため、鋼管柱の構造も簡素なものとなる。鋼管柱にブラケットがないため、運搬容積が小さくなり、運搬コストも安くなる。
【００１０】
上記接合プレートは、梁の幅方向に並ぶ２枚の分割接合プレートに分割されたものであっても良い。このように接合プレートが２枚に分割されていると、接合プレートを円形鋼管柱に現場溶接する場合に、梁を鋼管柱間に納めてから、２枚の分割接合プレートを梁の両側方から鋼管柱の外周面に持って来ることができ、梁の現場施工を容易に行うことができる。また、接合プレートを鋼管柱に工場溶接しておいて、現場で接合プレートに鋼管柱を溶接する場合には、接合プレートが上記のように２枚に分割されていると、次のように接合プレートの梁に対する溶接長を長く得ることができる。
【００１１】
すなわち、接合プレートが、梁の幅方向に並ぶ２枚の分割接合プレートに分割されたものである場合に、これら２枚の分割接合プレートは、梁幅中央側の辺、および梁接合端と反対側の辺で梁のフランジに隅肉溶接しても良い。このように接合プレートを分割構成とすることで、分割接合プレートの梁幅中央側の辺の隅肉溶接が可能となり、同サイズの接合プレートを１枚の非分割品とした場合に比べて、梁への接合プレートの溶接長が長くなる。そのため、接合強度を堅固にすることができる。
【００１２】
また、接合プレートが、梁の幅方向に並ぶ２枚の分割接合プレートに分割されたものであり、また接合プレートを梁に溶接されたものとする場合に、これら２枚の各分割接合プレートは、梁のフランジに１本の仮止め用のボルトで回動自在に取付けられ、梁接合端を鋼管柱の側面に合わせて鋼管柱に溶接されたものとしても良い。
この構成の場合、現場で梁を柱間に配置するときは、２枚の分割接合プレートを梁と干渉しないように両側方へ開いておき、柱間に梁を配置した後に、２枚の分割接合プレートを仮止め用のボルトを中心にして閉じ側へ回動させことで、各分割接合プレートの柱接合端を円形鋼管柱の側面に沿わせる。この後、各分割接合プレートを梁のフランジおよび鋼管柱へ溶接する。上記のように分割接合プレートを仮止め用のボルトで回動自在に取付けることで、分割接合プレートを梁に工場や現場の地上で取付けておいた状態で、梁を建込み位置へ吊り上げることができる。また、接合プレートの溶接に際して、接合プレートを位置決めする作業が、回動操作で済む。これらのため、接合プレートの取扱や溶接のための作業が簡単になる。
【００１３】
この発明において、上記接合プレートは柱接合端が梁幅よりも広がったものであれば良く、全長にわたって梁幅よりも広いものであっても良いが、上記接合プレートは、鋼管柱側の幅が幅広となるように、テーパ状に先広がり形状となったものであることが好ましい。テーパ状に先広がりとなった形状であれば、円形鋼管柱の面外変形耐力の確保が可能で、かつ接合プレートの余分な梁幅方向への突出部分がなく、材料の節減ともなる。このテーパ状の接合プレートは、柱接合端の幅を鋼管柱の径に応じて自由に変更し、鋼管柱の径等に応じて鋼管柱の面外変形耐力を適正化することができる。
【００１４】
この発明において、上記梁は、ウェブが鋼管柱の側面に溶接されたものであっても良い。その場合、例えば、接合プレートは鋼管柱に工場溶接しておき、現場で梁と接合プレートとの接合、および梁のウェブと鋼管柱側面との溶接を行う。
この構成の場合、梁のウェブと鋼管柱側面とを溶接した堅固な接合構造でありながら、従来の梁接合用のブラケットを鋼管柱に溶接する構造のものに比べ、鋼管柱からの出っ張りも少なくなるので、現場への運搬や構築前の保管が容易になる。
【００１５】
この発明において、上記梁は、上記鋼管柱の側面に上下方向に沿って接合されたガセットプレートにボルト接合されたものであっても良い。
この構成の場合、鋼管柱の側面に予め接合されたガセットプレートに梁のウェブをボルト接合した状態で、接合プレートの鋼管柱や梁への接合作業を行うことができる。そのため、現場での梁接合作業をより容易に行うことができる。
【００１６】
上記発明において、上記鋼管柱の梁接合部は、この鋼管柱の他の部分よりも肉厚の厚い厚肉部であっても良い。
このように厚肉部とした場合、ノンダイヤフラム構造であっても、鋼管柱の十分な面外変形耐力を確保できる。上記厚肉部は、素材となる鋼管を増肉加工した部分であっても良く、また鋼管柱に部分的に厚肉鋼管を用いたものであっても良い。
【００１７】
【発明の実施の形態】
この発明の第１の実施形態を図１と共に説明する。図１（Ａ），（Ｂ），（Ｃ）はこの実施形態に係る円形鋼管柱の柱梁接合構造を示す正面図，側面図および平面図である。この柱梁接合構造は、円形の鋼管柱１に、この鋼管柱１よりも幅狭のＨ形鋼製の梁２を接合したものであって、鋼管柱１の梁接合部がノンダイヤフラム構造とされている。円形鋼管柱１の梁接合部は、この鋼管柱１の他の部分よりも肉厚の厚い厚肉部１ａとされている。上記梁２は、梁端部で上下のフランジ２ａ，２ａにそれぞれ接合される接合プレート３，３を介して鋼管柱１に接合される。各接合プレート３は、鋼管柱１側の幅が幅広となるように、テーパ状の先広がり形状とされており、柱接合端が梁幅よりも広がっている。この広がった柱接合端は、鋼管柱１の側面に沿う円弧形状とされている。上記接合プレート３は、梁２の幅方向に並ぶ２枚の分割接合プレート４，４に分割されている。換言すれば、梁幅方向に並ぶ２枚の分割接合プレート４，４を合わせて「接合プレート３」と称している。この接合プレート３は、予め工場において鋼管柱１の側面に突き合わせ溶接等により溶接される。
【００１８】
鋼管柱１は、この接合プレート３が溶接された状態で、工場より現場に運搬され、建てられる。現場では、この建てられた鋼管柱１の上下の接合プレート３，３間に梁端部が嵌まり込むように、梁２が吊り上げて配置される。この後、接合プレート３が梁２の上下のフランジ２ａにそれぞれ溶接される。この場合に、図１（Ｃ）のように、接合プレート３を構成する２枚の分割接合プレート４，４は、フランジ２ａに重なる辺の全てが隅肉溶接される。接合プレート３がこのようなテーパ形状である場合、その各分割接合プレート４のフランジ２ａと重なる辺は、梁幅中央側の辺４ａ、梁接合端と反対側の辺４ｂ、および梁幅外側の斜めの辺４ｃの一部となる。また、梁２は、そのウェブ２ｂの端部が鋼管柱１の側面に溶接される。
【００１９】
この円形鋼管柱の柱梁接合構造によると、梁２の上下フランジ２ａを、接合プレート３を介して鋼管柱１に接合するようにしたため、円形鋼管柱１の外周形状に沿わせる開先加工が、平板状の部材である接合プレート４を円弧状に加工するだけで良く、従来のＨ形鋼の上下フランジに円弧状の加工を行うものに比べて加工が容易である。そのため、安価に構成できる。梁２の上下フランジ２ａに発生する荷重は、接合プレート３を介して鋼管柱１に伝わる。この場合に、接合プレート３は柱接合端が梁幅よりも広がっているため、広い範囲で接合プレート３と接合できて、鋼管柱１の面外曲げ耐力等の面外変形耐力が確保される。また、ノンダイヤフラム構造であり、しかも鋼管柱１に梁端部となるブラケットが不要となるため、鋼管柱１の構造も簡素なものとなる。鋼管柱１にブラケットがないため、運搬容積が小さくなり、運搬コストも安くなる。
【００２０】
また、接合プレート３は、梁２の幅方向に並ぶ２枚の分割接合プレート４からなるものとしているので、その各分割接合プレート４は、梁幅中央側の辺４ａ、梁接合端と反対側の辺４ｂ、および梁幅外側の斜めの辺４ｃの一部で梁２のフランジ２ａに隅肉溶接することができる。このため、接合プレート３を１枚の非分割のものとした場合に比べて、梁２への接合プレート３の溶接長が長くなる。そのため、十分な接合強度を確保できる。
さらに、円形鋼管柱１は梁接合部が厚肉部１ａとされているので、ノンダイヤフラム構造でありながら、十分な耐力が確保される。
【００２１】
なお、この実施形態において、接合プレート３の鋼管柱１への溶接は、現場で行うようにしても良い。その場合、梁２を吊り上げて鋼管柱１間に配置した状態で、接合プレート３の鋼管柱１への溶接および梁２への溶接を行う。接合プレート３の鋼管柱１への溶接と梁２への溶接とは、いずれを先に行っても良い。鋼管１間に梁２を配置した後に、接合プレート３の鋼管柱１への溶接を行うようにすれば、接合プレート３が梁２の鋼管柱１間への配置の邪魔となることがない。
【００２２】
図２（Ａ），（Ｂ），（Ｃ）は、この発明の他の実施形態に係る円形鋼管柱の柱梁接合構造を示す正面図，側面図および平面図である。この柱梁接合構造は、図１に示す第１の実施形態において、接合プレート３を構成する２枚の分割接合プレート４，４を、予め工場で円形鋼管柱１の側面に溶接しておき、現場でこれら２枚の分割接合プレート４，４を、梁２のフランジ２ａにボルト５で接合したものである。ボルト５には高力ボルトが用いられる。梁２のウェブ２ｂの端部を円形鋼管柱１の側面に溶接すること、およびその他の構造は第１の実施形態の場合と同じである。
この実施形態の場合、現場での溶接作業を無くすことができ、現場作業が容易になり、接合の信頼性が向上する。その他の効果は図１の実施形態の場合と同様である。
【００２３】
図３（Ａ），（Ｂ）はこの発明のさらに他の実施形態に係る円形鋼管柱の柱梁接合構造を示す平面図および正面図である。この柱梁接合構造では、図１に示す第１の実施形態において、円形鋼管柱１の梁接合部の側面に、予め工場で上下方向に沿うガセットプレート６が溶接により接合される。接合プレート３は、鋼管柱１に対して現場溶接とする。現場では、先ず梁２のウェブ２ｂの端部がガセットプレート６にボルト７で接合される。接合プレート３を構成する２枚の分割接合プレート４，４は、梁２のフランジ２ａに１本の仮止め用のボルト５Ａで回動自在に取付けられる。この仮止め用のボルト５Ａによる分割接合プレート４の取付けは、現場で梁２の吊り上げ前に行うようにしても、予め工場で行うようにしても良い。ボルト５Ａで仮止めした分割接合プレート４，４は、梁２の柱１間への配置作業時には図４に実線で示すように互いに開いておく。梁２の柱１間への配置が完了し、ガセットプレート６への梁ウェブ２ｂのボルト接合の後に、両分割接合プレート４を互いに閉じ回動させて、その柱接合端を鋼管柱１の外面に沿わせる。この後、分割接合プレート４を鋼管柱１の側面に溶接する。なお、円形鋼管柱１における梁接合部の側面には、分割接合プレート４を円形鋼管柱１に溶接するときの裏当て材８を予め工場で溶接しておく。その他の構成は図１の実施形態と同様である。
【００２４】
この実施形態の場合、２枚の分割接合プレート４，４を梁２のフランジ２ａにボルト５Ａで回動自在に仮止めするので、鋼管柱１間への梁２の配置作業に接合プレート３が邪魔とならない。また、鋼管柱１に予め接合されたガセットプレート６に梁２のウェブ２ｂをボルト７で接合することからも、現場での梁接合作業をより簡単に行うことができる。
【００２５】
図５はこの発明のさらに他の実施形態に係る円形鋼管柱の柱梁接合構造を示す平面図である。この柱梁接合構造は、図３および図４に示す実施形態において、接合プレート３を構成する２枚の分割接合プレート４，４を、それぞれ複数のボルト５で梁２のフランジ２ａに接合するようにしたものである。これらのボルト５のうち、１本のボルト５Ａは、仮止め用とする。分割接合プレート４および梁２のフランジ２ａには、ボルト５，５Ａを挿通させる複数のボルト挿通孔（図示せず）がそれぞれ形成される。
現場では、図３および図４の実施形態の場合と同様に、分割接合プレート４を１本の仮止め用のボルト５Ａだけで取付けて、梁２の鋼管柱１間への配置を行い、その後に分割接合プレート４の梁２への各ボルト５による接合、および分割接合プレート４の先端の鋼管柱１への突き合わせ溶接を行う。その他の構成は図３および図４の実施形態と同様である。
この実施形態の場合、分割接合プレート４の梁２への接合がボルト接合となるので、現場溶接が少なくなり、作業性および信頼性が向上する。
【００２６】
図６はこの発明のさらに他の実施形態に係る円形鋼管柱の柱梁接合構造を示す平面図である。この柱梁接合構造は、図３，図４にに示す実施形態において、接合プレート３を１枚の非分割のプレートとしたものである。その他の構成は図１の実施形態と同様である。
【００２７】
この実施形態の場合、接合プレート３が１枚のプレートからなるので、梁２のフランジ２ａに接合プレート３を隅肉溶接するときの溶接長が得難いが、裏面側から溶接することなどで、溶接長が確保される。その他の効果は図３，図４の実施形態と同様である。図１に示す第１実施形態においても、この接合プレート３を１枚の非分割のプレートとした構成が採用できる。
【００２８】
図７（Ａ），（Ｂ）はこの発明のさらに他の実施形態に係る円形鋼管柱の柱梁接合構造を示す正面図および平面図である。この柱梁接合構造は、図１に示す実施形態において、円形鋼管柱１を、通常の肉厚の円形鋼管１Ａと、厚肉の円形鋼管１Ｂとを溶接することにより縦に連結して形成し、厚肉の円形鋼管１Ｂの部分を梁接合部としたものである。その他の構成は図１の実施形態と同様である。
このように構成することにより、梁接合部を厚肉部１ａとした円形鋼管柱１を安価に形成できる。図３，図４の実施形態など、他の各実施形態においても、この厚肉の円形鋼管１Ｂにより厚肉部１ａを構成した構成が採用できる。
【００２９】
図８はこの発明のさらに他の実施形態に係る円形鋼管柱の柱梁接合構造を示す平面図である。この柱梁接合構造は、図１に示す実施形態において、円形鋼管柱１内にコンクリート９を充填してＣＦＴ構造の鋼管柱としたものである。その他の構成は図１の実施形態の場合と同様である。このように構成することにより、円形鋼管柱１の圧縮耐力の向上が図れる。
【００３０】
なお、上記した各実施形態では、円形鋼管柱１として、梁接合部が厚肉部１ａとなった鋼管柱を使用した場合を示したが、これに限らず通常の全長に均等な肉厚の円形鋼管柱を使用しても良い。
【００３１】
【発明の効果】
この発明の円形鋼管柱の柱梁接合構造は、円形の鋼管柱に、この鋼管柱よりも幅狭のＨ形鋼製の梁を接合した柱梁接合構造において、上記鋼管柱の梁接合部がノンダイヤフラム構造であり、上記梁は、梁端部で上下のフランジにそれぞれ接合された接合プレートを介して上記鋼管柱に接合され、上記各接合プレートは柱接合端が梁幅よりも広がっていて、この柱接合端が鋼管柱の側面に沿う円弧形状であり、鋼管柱の側面に突合わせ溶接されたものとしたため、構造が簡素で、堅固な接合が行え、かつ加工が容易で安価に構築することができる。
【図面の簡単な説明】
【図１】（Ａ）はこの発明の一実施形態に係る円形鋼管柱の柱梁接合構造の正面図、（Ｂ）は同側面図、（Ｃ）は同平面図である。
【図２】（Ａ）はこの発明の他の実施形態に係る円形鋼管柱の柱梁接合構造の正面図、（Ｂ）は同側面図、（Ｃ）は同平面図である。
【図３】（Ａ）はこの発明のさらに他の実施形態に係る円形鋼管柱の柱梁接合構造の平面図、（Ｂ）は同正面図である。
【図４】同柱梁接合構造の梁建方説明図である。
【図５】この発明のさらに他の実施形態に係る円形鋼管柱の柱梁接合構造の平面図である。
【図６】この発明のさらに他の実施形態に係る円形鋼管柱の柱梁接合構造の平面図である。
【図７】（Ａ）はこの発明のさらに他の実施形態に係る円形鋼管柱の柱梁接合構造の正面図、（Ｂ）は同平面図である。
【図８】この発明のさらに他の実施形態に係る円形鋼管柱の柱梁接合構造の平面図である。
【図９】（Ａ）は従来例の平面図、（Ｂ）は同正面図である。
【図１０】他の従来例の正面図である。
【図１１】（Ａ）はさらに他の従来例の平面図、（Ｂ）は同正面図である。
【図１２】同従来例における梁端部Ｒ加工の説明図である。
【図１３】円形鋼管柱に梁を現場溶接する場合の問題点を示す説明図である。
【図１４】円形鋼管柱に狭幅の梁を接合する場合の問題点を示す説明図である。
【符号の説明】
１…円形鋼管柱
１ａ…厚肉部
２…梁
２ａ…フランジ
２ｂ…ウェブ
３…接合プレート
４…分割接合プレート
５Ａ…仮止め用ボルト
６…ガセットプレート
７…ボルト[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a non-diaphragm type column-beam joint structure in which an H-shaped steel beam narrower than a steel tube column is joined to a circular steel tube column.
[0002]
[Prior Art and Problems to be Solved by the Invention]
Conventionally, as a column-beam joint structure of a circular steel pipe column, a diaphragm type shown in FIG. 9 is generally employed. In this conventional example, upper and lower two-stage diaphragms 29 having an octagonal shape are welded in advance to a beam joint of a circular steel pipe column 21 at a factory, and one side of each of the upper and lower two-stage diaphragms 29, 29. A bracket 28 made of H-shaped steel is welded to the side surface of the steel pipe column 21 between the two diaphragms 29, 29. At the site, the beam 22 made of H-section steel is bolted to the bracket 28 of the steel pipe column 21 via beam joints 23A, 23B, and 23C using attachment plates. The welding of the bracket 28 to the steel pipe column 21 is performed by attaching the ends of the upper and lower flanges 28a of the bracket 28 to corresponding one sides of the upper and lower diaphragms 29, 29, and the end of the web 28b of the bracket 28 to the side surface of the steel pipe column 21. Each is done by butt welding.
[0003]
However, in such a column-beam joint structure, the number of man-hours for processing the steel pipe column 21 in the factory increases, and the beam joints 23A, 23B, and 23C of the attachment plates are also required, which increases the cost.
[0004]
FIG. 10 shows another example of the diaphragm type. In this conventional example, upper and lower two-stage diaphragms 29, 29 similar to the case of the conventional example of FIG. 9 are welded in advance to the beam joint portion of the circular steel pipe column 21 at the factory, and between these two diaphragms 29, 29. The gusset plate 26 is welded to the side of the steel pipe column 21. At the site, the end of the web 22b of the beam 22 is bolted to the gusset plate 26 of the steel pipe column 21, and the ends of the upper and lower flanges 22a, 22a of the beam 22 are butt-welded to corresponding sides of both diaphragms 29, 29.
[0005]
In the case of this conventional example, a bracket and an attached plate type beam joint are unnecessary, but the diaphragm type is the same as the conventional example of FIG. .
[0006]
As a non-diaphragm type conventional example, there is one using a thickened steel pipe column shown in FIG. In this conventional example, a beam joint of a circular steel pipe column 21 is reinforced as a thickened portion 21a, and a bracket 28A made of an H-shaped steel is welded to the beam joint of the steel pipe column 21 at a factory in advance. At the site, the beam 22 is bolted to the bracket 28A of the steel pipe column 21 via the butt plate type beam joints 23A, 23B, 23C. The welding of the bracket 28A to the steel pipe column 21 is performed by forming an edge of the bracket 28A in an arc shape in accordance with the outer diameter of the steel pipe column 21 as shown in FIG.
[0007]
As described above, when the diaphragm is omitted, the end of the beam 22 (specifically, the bracket 28A) must be processed into an arc shape in accordance with the outer diameter of the steel pipe column 21. Further, as shown in FIG. 13, even if the beam 22 whose end is R-processed is to be inserted from the side between the steel pipe columns 21 already erected at the site, the end of the R-processed portion is not required. Cannot be accommodated because it protrudes from the center and interferes with the circular steel pipe column 21. Therefore, as described above, the bracket 28A must be welded to the steel pipe column 21 in advance at the factory, and the beam 22 must be bolted at the site via the attached plate-type beam joints 23A, 23B, and 23C. Since the bracket 28A and the attachment plate are used as described above, the cost is also increased.
Further, in the case of this conventional example in which the diaphragm is omitted, if the beam flange width is small, the out-of-plane deformation resistance of the steel pipe column 21 is small, so that a large tensile force T is applied to the flange 22a of the beam 22 by the beam end moment as shown in FIG. Works, the steel pipe column 21 may be deformed.
For this reason, the width of the tip of the upper and lower flanges 22a of the beam 22 was considered to be increased in a tapered shape. The beam flange width can be changed in this manner by using a beam 22 made of a type in which the upper and lower flanges 22a and the web are welded and assembled, that is, a so-called built-in H-shaped steel. However, when such a built-in H-shaped steel is used to machine the flange width into a tapered shape, the machining becomes complicated and causes high cost.
[0008]
An object of the present invention is to solve such a problem and to provide a beam-column joint structure of a circular steel pipe column which has a simple structure, can perform firm joining, can be easily processed, and can be constructed at low cost.
[0009]
[Means for Solving the Problems]
The beam-to-column joint structure for a circular steel pipe column according to the present invention is a beam-to-column joint structure in which an H-shaped steel beam narrower than the steel pipe column is joined to the circular steel pipe column. It has a non-diaphragm structure, and the beam is joined to the steel pipe column via joining plates joined to upper and lower flanges at beam ends, respectively, and the joining end of each of the joining plates is wider than the beam width. The column joint end has an arc shape along the side surface of the steel tube column, and is butt-welded to the side surface of the steel tube column. The joining between the joining plate and the beam may be welding or bolt joining. The width of the beam is, for example, equal to or smaller than the width of one side of a square inscribed in a circle which is a cross section of the outer peripheral surface of the circular steel pipe column.
According to this configuration, since the upper and lower flanges of the beam are joined to the steel pipe column via the joining plate, the groove processing along the outer peripheral shape of the circular steel pipe column causes the joining plate, which is a flat member, to be formed in an arc shape. This is easier than the conventional method in which the upper and lower flanges of the H-section steel are processed in an arc shape. Therefore, it can be constructed at low cost. The load generated on the flange of the beam is transmitted to the steel column via the joint plate. In this case, since the joint plate has a column joint end wider than the beam width, the joint plate can be joined to the steel tube column in a wide range, and the out-of-plane deformation resistance of the steel tube column is secured. Further, since the non-diaphragm structure is used, and a bracket serving as a beam end is not required for the steel pipe column, the structure of the steel pipe column is also simplified. Since there is no bracket on the steel pipe column, the transport volume is reduced and the transport cost is reduced.
[0010]
The joining plate may be divided into two divided joining plates arranged in the beam width direction. When the joining plate is divided into two pieces in this way, when welding the joining plate to a circular steel pipe column, the beam is placed between the steel pipe columns, and then the two split joining plates are attached from both sides of the beam. It can be brought to the outer peripheral surface of the steel pipe column, and the beam can be easily constructed on site. In addition, when the joining plate is factory-welded to the steel column and the steel column is welded to the joining plate on site, if the joining plate is divided into two pieces as described above, the joining is performed as follows. A longer welding length of the plate to the beam can be obtained.
[0011]
That is, when the joining plate is divided into two divided joining plates arranged in the beam width direction, these two divided joining plates are opposite to the beam width center side and the beam joining end. Fillet welding may be performed to the flange of the beam at the side. By forming the joining plate in the divided configuration in this manner, it becomes possible to weld the fillet on the side of the center of the beam width of the divided joining plate. The welding length of the joining plate to the beam becomes longer. Therefore, the joining strength can be increased.
[0012]
Further, when the joining plate is divided into two divided joining plates arranged in the beam width direction, and when the joining plate is welded to the beam, each of the two divided joining plates is Alternatively, the beam may be rotatably attached to the flange of the beam with one temporary fixing bolt, and the beam joint end may be welded to the steel pipe column so as to match the side of the steel pipe column.
In the case of this configuration, when placing the beam between the columns at the site, the two split joint plates are opened on both sides so as not to interfere with the beam, and after placing the beam between the columns, the two split plates are split. By rotating the joining plate to the closing side about the temporary fixing bolt, the column joining end of each divided joining plate is made to follow the side surface of the circular steel pipe column. Thereafter, each split joint plate is welded to the beam flange and the steel column. By mounting the split joint plate rotatably with the temporary fixing bolts as described above, it is possible to lift the beam to the building position with the split joint plate attached to the beam on the ground at the factory or site. it can. Further, when welding the joining plate, the operation of positioning the joining plate can be performed by a rotating operation. For these reasons, handling of the joining plate and work for welding are simplified.
[0013]
In the present invention, it is sufficient that the joint plate has a column joint end wider than the beam width, and may be wider than the beam width over the entire length, but the joint plate has a steel pipe column side width. It is preferable that the tapered shape has a widened shape so as to be wide. If the shape is tapered and widened, it is possible to secure the resistance to out-of-plane deformation of the circular steel pipe column, and there is no extra projecting portion in the beam width direction of the joining plate, thereby saving material. This tapered joint plate can freely change the width of the column joint end according to the diameter of the steel tube column, and optimize the out-of-plane deformation resistance of the steel tube column according to the diameter of the steel tube column and the like.
[0014]
In the present invention, the beam may have a web welded to a side surface of a steel pipe column. In this case, for example, the joint plate is factory-welded to the steel pipe column, and the beam is joined to the joint plate at the site and the web of the beam is welded to the side of the steel pipe column.
In the case of this configuration, it has a solid joint structure in which the beam web is welded to the side of the steel tube column, but also has less protrusion from the steel tube column than the conventional structure in which the beam joint bracket is welded to the steel tube column. Therefore, transportation to the site and storage before construction become easy.
[0015]
In the present invention, the beam may be bolted to a gusset plate that is vertically joined to a side surface of the steel pipe column.
In the case of this configuration, the joining operation of the joining plate to the steel pipe column or the beam can be performed in a state where the beam web is bolted to the gusset plate previously joined to the side surface of the steel tube column. Therefore, the beam joining operation on the site can be performed more easily.
[0016]
In the above invention, the beam joint of the steel pipe column may be a thick wall portion thicker than other portions of the steel pipe column.
In the case of such a thick portion, a sufficient out-of-plane deformation resistance of the steel pipe column can be ensured even with a non-diaphragm structure. The thick portion may be a portion obtained by increasing the thickness of a steel pipe serving as a material, or may be a portion in which a thick steel pipe is partially used for a steel pipe column.
[0017]
BEST MODE FOR CARRYING OUT THE INVENTION
A first embodiment of the present invention will be described with reference to FIG. 1 (A), 1 (B), and 1 (C) are a front view, a side view, and a plan view showing a beam-column joint structure of a circular steel pipe column according to this embodiment. This column-beam joint structure is formed by joining an H-shaped steel beam 2 narrower than the steel tube column 1 to a circular steel tube column 1, and the beam joint portion of the steel tube column 1 has a non-diaphragm structure. Have been. The beam joint of the circular steel tube column 1 is a thick portion 1a which is thicker than other portions of the steel tube column 1. The beam 2 is joined to the steel pipe column 1 via joining plates 3, 3 joined to upper and lower flanges 2 a, 2 a at the beam ends. Each joining plate 3 is tapered and widened so that the width on the steel tube column 1 side is wide, and the column joining end is wider than the beam width. The expanded column joint end is formed in an arc shape along the side surface of the steel pipe column 1. The joining plate 3 is divided into two divided joining plates 4 and 4 arranged in the width direction of the beam 2. In other words, the two divided joining plates 4 and 4 arranged in the beam width direction are collectively referred to as “joining plate 3”. The joining plate 3 is previously welded to the side surface of the steel pipe column 1 at a factory by butt welding or the like.
[0018]
The steel pipe column 1 is transported from a factory to a site and built in a state where the joining plate 3 is welded. At the site, the beam 2 is lifted and arranged so that the beam end is fitted between the upper and lower joining plates 3 and 3 of the steel pipe column 1 thus built. Thereafter, the joining plate 3 is welded to the upper and lower flanges 2a of the beam 2, respectively. In this case, as shown in FIG. 1 (C), the two split joining plates 4 and 4 constituting the joining plate 3 are fillet welded on all sides overlapping the flange 2a. When the joining plate 3 has such a tapered shape, the side overlapping with the flange 2a of each of the divided joining plates 4 includes a side 4a on the center side of the beam width, a side 4b on the side opposite to the beam joining end, and an outer side of the beam width. It becomes a part of the oblique side 4c. Further, the end of the web 2 b of the beam 2 is welded to the side surface of the steel pipe column 1.
[0019]
According to the column-to-beam joining structure of the circular steel pipe column, the upper and lower flanges 2a of the beam 2 are joined to the steel pipe column 1 via the joining plate 3, so that a beveling process along the outer peripheral shape of the circular steel pipe column 1 is performed. It is only necessary to process the joining plate 4 which is a plate-shaped member into an arc shape, and the machining is easier than the conventional process in which the upper and lower flanges of the H-shaped steel are arc-shaped. Therefore, it can be constructed at low cost. The load generated on the upper and lower flanges 2 a of the beam 2 is transmitted to the steel pipe column 1 via the joint plate 3. In this case, since the joint plate 3 has a column joint end wider than the beam width, the joint plate 3 can be joined to the joint plate 3 in a wide range, and the out-of-plane deformation strength such as the out-of-plane bending strength of the steel pipe column 1 is secured. . Further, since the steel pipe column 1 has a non-diaphragm structure and does not require a bracket serving as a beam end on the steel pipe column 1, the structure of the steel pipe column 1 is also simplified. Since there is no bracket on the steel pipe column 1, the transport volume is reduced and the transport cost is reduced.
[0020]
Further, since the joining plate 3 is composed of two divided joining plates 4 arranged in the width direction of the beam 2, each of the divided joining plates 4 has a side 4a on the center side of the beam width and a side opposite to the beam joining end. Can be fillet welded to the flange 2a of the beam 2 at the side 4b and a part of the oblique side 4c outside the beam width. For this reason, the welding length of the joining plate 3 to the beam 2 is increased as compared with the case where the joining plate 3 is made of one undivided one. Therefore, sufficient bonding strength can be secured.
Furthermore, since the circular steel pipe column 1 has a thick-walled portion 1a at the beam joint, sufficient strength is ensured while having a non-diaphragm structure.
[0021]
In this embodiment, welding of the joining plate 3 to the steel pipe column 1 may be performed on site. In that case, the welding of the joining plate 3 to the steel pipe column 1 and the beam 2 is performed in a state where the beam 2 is lifted and arranged between the steel pipe columns 1. Either welding of the joining plate 3 to the steel pipe column 1 or welding to the beam 2 may be performed first. If the joining plate 3 is welded to the steel pipe column 1 after the beam 2 is arranged between the steel pipes 1, the joining plate 3 does not hinder the arrangement of the beam 2 between the steel tube columns 1.
[0022]
2 (A), 2 (B), and 2 (C) are a front view, a side view, and a plan view showing a beam-column joint structure of a circular steel pipe column according to another embodiment of the present invention. In the column-beam joint structure, in the first embodiment shown in FIG. 1, two divided joint plates 4 constituting the joint plate 3 are welded in advance to the side surface of the circular steel pipe column 1 at a factory. At the site, these two divided joining plates 4 and 4 are joined to the flange 2 a of the beam 2 with bolts 5. As the bolt 5, a high-strength bolt is used. The welding of the end of the web 2b of the beam 2 to the side surface of the circular steel column 1 and other structures are the same as those in the first embodiment.
In the case of this embodiment, the on-site welding work can be eliminated, the on-site work is facilitated, and the reliability of joining is improved. Other effects are the same as those of the embodiment of FIG.
[0023]
FIGS. 3A and 3B are a plan view and a front view showing a column-to-beam joining structure of a circular steel tubular column according to still another embodiment of the present invention. In this column-beam joint structure, in the first embodiment shown in FIG. 1, a gusset plate 6 along the vertical direction is welded in advance to the side surface of the beam joint of the circular steel tube column 1 at a factory. The joining plate 3 is welded to the steel pipe column 1 in situ. At the site, first, the end of the web 2 b of the beam 2 is joined to the gusset plate 6 with the bolt 7. The two split joining plates 4 and 4 constituting the joining plate 3 are rotatably attached to the flange 2a of the beam 2 with one temporary fixing bolt 5A. The attachment of the split joining plate 4 by the temporary fixing bolts 5A may be performed before the beam 2 is lifted on site or may be performed in a factory in advance. The divided joining plates 4 and 4 temporarily fixed with the bolts 5A are opened from each other as shown by a solid line in FIG. After the arrangement of the beam 2 between the columns 1 is completed, and after the bolt connection of the beam web 2 b to the gusset plate 6, the two divided connecting plates 4 are closed and rotated to each other, and the column connecting end is connected to the outer surface of the steel tube column 1. Along. Thereafter, the split joint plate 4 is welded to the side surface of the steel pipe column 1. Note that a backing material 8 for welding the divided joint plate 4 to the circular steel pipe column 1 is previously welded to the side surface of the beam joint of the circular steel pipe column 1 at a factory. Other configurations are the same as those of the embodiment of FIG.
[0024]
In the case of this embodiment, the two divided joining plates 4 and 4 are temporarily fixed rotatably to the flange 2a of the beam 2 with the bolts 5A, so that the joining plate 3 is used for the work of arranging the beam 2 between the steel pipe columns 1. Not in the way. Further, since the web 2b of the beam 2 is joined to the gusset plate 6 previously joined to the steel pipe column 1 with the bolt 7, the beam joining operation on site can be performed more easily.
[0025]
FIG. 5 is a plan view showing a column-to-beam joining structure of a circular steel pipe column according to still another embodiment of the present invention. In the embodiment shown in FIGS. 3 and 4, the column-beam joining structure is such that the two divided joining plates 4, 4 constituting the joining plate 3 are joined to the flange 2 a of the beam 2 with a plurality of bolts 5, respectively. It was made. Of these bolts 5, one bolt 5A is used for temporary fixing. A plurality of bolt insertion holes (not shown) through which the bolts 5 and 5A are inserted are formed in the split joining plate 4 and the flange 2a of the beam 2, respectively.
At the site, as in the case of the embodiment of FIG. 3 and FIG. 4, the split joining plate 4 is attached with only one temporary fixing bolt 5A, and the beam 2 is arranged between the steel pipe columns 1. Then, the divided joining plate 4 is joined to the beam 2 by the bolts 5 and the butt welding of the tip of the divided joining plate 4 to the steel pipe column 1 is performed. Other configurations are the same as those of the embodiment of FIGS. 3 and 4.
In the case of this embodiment, since the joining of the split joining plate 4 to the beam 2 is performed by bolt joining, on-site welding is reduced, and workability and reliability are improved.
[0026]
FIG. 6 is a plan view showing a column-to-column joint structure of a circular steel pipe column according to still another embodiment of the present invention. In this embodiment, the joint plate 3 is a single non-divided plate in the embodiment shown in FIGS. Other configurations are the same as those of the embodiment of FIG.
[0027]
In the case of this embodiment, since the joining plate 3 is formed of one plate, it is difficult to obtain a welding length when the joining plate 3 is welded to the flange 2a of the beam 2 by welding. Length is secured. Other effects are the same as those of the embodiment of FIGS. Also in the first embodiment shown in FIG. 1, a configuration in which the joining plate 3 is a single non-divided plate can be adopted.
[0028]
FIGS. 7A and 7B are a front view and a plan view showing a column-to-beam joint structure of a circular steel pipe column according to still another embodiment of the present invention. In the embodiment shown in FIG. 1, this column-beam joint structure is formed by connecting a circular steel pipe column 1 vertically by welding a circular steel pipe 1A having a normal thickness and a circular steel pipe 1B having a large thickness. The thick circular steel pipe 1B is used as a beam joint. Other configurations are the same as those of the embodiment of FIG.
With such a configuration, the circular steel pipe column 1 having the beam joint portion having the thick portion 1a can be formed at low cost. In each of the other embodiments such as the embodiment of FIGS. 3 and 4, a configuration in which the thick wall portion 1a is formed by the thick circular steel pipe 1B can be adopted.
[0029]
FIG. 8 is a plan view showing a column-beam joint structure of a circular steel pipe column according to still another embodiment of the present invention. In this embodiment, the circular steel pipe column 1 is filled with concrete 9 in the embodiment shown in FIG. 1 to form a steel pipe column having a CFT structure. Other configurations are the same as those in the embodiment of FIG. With this configuration, the compression strength of the circular steel tubular column 1 can be improved.
[0030]
In each of the above-described embodiments, a case in which a steel pipe column in which a beam joint is a thick wall portion 1a is used as the circular steel pipe column 1 is not limited thereto. A round steel pipe column may be used.
[0031]
【The invention's effect】
The beam-to-column joint structure for a circular steel pipe column according to the present invention is a beam-to-column joint structure in which an H-shaped steel beam narrower than the steel pipe column is joined to the circular steel pipe column. It has a non-diaphragm structure, and the beam is joined to the steel pipe column via joining plates joined to upper and lower flanges at beam ends, respectively, and the joining end of each of the joining plates is wider than the beam width. The joint end of this column has an arc shape along the side of the steel pipe column, and is butt-welded to the side of the steel pipe column, so the structure is simple, solid connection can be performed, and processing is easy and inexpensive. can do.
[Brief description of the drawings]
1A is a front view of a beam-column joint structure for a circular steel pipe column according to an embodiment of the present invention, FIG. 1B is a side view thereof, and FIG. 1C is a plan view thereof.
FIG. 2A is a front view of a beam-column joint structure for a circular steel pipe column according to another embodiment of the present invention, FIG. 2B is a side view thereof, and FIG. 2C is a plan view thereof.
FIG. 3A is a plan view of a column-to-beam joint structure of a circular steel pipe column according to still another embodiment of the present invention, and FIG. 3B is a front view of the same.
FIG. 4 is an explanatory view of a beam construction of the column-beam joint structure.
FIG. 5 is a plan view of a beam-column joint structure for a circular steel pipe column according to still another embodiment of the present invention.
FIG. 6 is a plan view of a beam-column joint structure of a circular steel pipe column according to still another embodiment of the present invention.
FIG. 7A is a front view of a beam-column joint structure for a circular steel tube column according to still another embodiment of the present invention, and FIG. 7B is a plan view of the same.
FIG. 8 is a plan view of a beam-column joint structure for a circular steel pipe column according to still another embodiment of the present invention.
FIG. 9A is a plan view of a conventional example, and FIG. 9B is a front view of the same.
FIG. 10 is a front view of another conventional example.
FIG. 11A is a plan view of still another conventional example, and FIG. 11B is a front view of the same.
FIG. 12 is an explanatory view of beam end R processing in the conventional example.
FIG. 13 is an explanatory diagram showing a problem in the case where a beam is welded to a circular steel pipe column in place.
FIG. 14 is an explanatory diagram showing a problem when a narrow beam is joined to a circular steel pipe column.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Round steel pipe column 1a ... Thick part 2 ... Beam 2a ... Flange 2b ... Web 3 ... Joining plate 4 ... Split joining plate 5A ... Temporary fixing bolt 6 ... Gusset plate 7 ... Bolt

Claims

In a beam-column joint structure in which an H-shaped steel beam narrower than the steel tube column is joined to a circular steel tube column, a beam joint of the steel tube column has a non-diaphragm structure, and the beam has a beam end portion. The joining plate is joined to the steel pipe column through joining plates respectively joined to the upper and lower flanges, and each of the joining plates has a column joint end wider than the beam width, and the column joint end is an arc along the side surface of the steel tube column. Column-beam joint structure of circular steel pipe columns that are shaped and butt-welded to the side of the steel pipe columns.

2. The beam-column joint structure of a circular steel pipe column according to claim 1, wherein the joint plate is divided into two divided joint plates arranged in the width direction of the beam.

3. The beam-column joint structure according to claim 2, wherein the two split joint plates are fillet welded to the flange of the beam at the side on the center side of the beam width and on the side opposite to the beam joint end.

In claim 3, each of the two split joint plates is rotatably attached to the flange of the beam with one temporary fixing bolt, and the beam joint end is aligned with the side surface of the steel tube column and welded to the steel tube column. Beam-to-column joint structure of circular steel tubular columns.

The beam-column joint structure for a circular steel pipe column according to any one of claims 1 to 4, wherein the connecting plate has a tapered and widened shape so that the width on the steel pipe column side is wide.

The beam-joint structure for a circular steel pipe column according to any one of claims 1 to 5, wherein the beam has a web welded to a side surface of the steel pipe column.

The beam-column joint structure for a circular steel pipe column according to any one of claims 1 to 5, wherein the beam is bolted to a gusset plate that is vertically joined to a side surface of the steel pipe column.

8. A beam-column joint structure for a circular steel pipe column according to any one of claims 1 to 7, wherein the beam connection part of the steel pipe column is a thick part thicker than other parts of the steel pipe column.