JP4693299B2

JP4693299B2 - Column base connection structure

Info

Publication number: JP4693299B2
Application number: JP2001241845A
Authority: JP
Inventors: 正裕鈴木; 哲也菅野; 丈史槙枝
Original assignee: Asahi Kasei Construction Materials Corp
Current assignee: Asahi Kasei Construction Materials Corp
Priority date: 2001-08-09
Filing date: 2001-08-09
Publication date: 2011-06-01
Anticipated expiration: 2021-08-09
Also published as: JP2003055984A

Description

【０００１】
【発明の属する技術分野】
本発明は、建築物の柱の脚部と基礎構造体とを連結した柱脚連結構造に係り、特に中低層鉄骨建築物の柱脚連結構造において柱の脚部の回転変形に対する剛性が低い状態で柱の脚部と基礎構造体とを連結した柱脚連結構造に関するものである。
【０００２】
【従来の技術】
従来、鉄骨柱の脚部を鉄筋コンクリート等で形成された基礎構造体に固定する方法としては、柱下端部に固定したベースプレートを基礎構造体に埋め込まれたアンカーボルト等に固定するものが一般である。
【０００３】
通常、ベースプレートは柱脚部の周囲に平面的に大きく張り出しており、アンカーボルトはこの張り出しているベースプレート面において、柱材の断面に対して略均等に配置されている。
【０００４】
このような柱脚連結構造によれば、地震等の外力によって柱の脚部が回転しようとしてもベースプレートの浮き上がり方向はアンカーボルトが引っ張り抵抗し、ベースプレートの沈下方向は基礎構造体が圧縮抵抗して大きな回転抵抗が発生し、上部鉄骨架構の変形を抑えることが出来る。
【０００５】
このような従来の柱脚連結構造によれば、柱材や上部梁材の断面が小さくても中地震時における変形を小さくすることが出来るという特長があるものの大地震時においては柱脚部分が塑性化して破壊する虞れもある。
【０００６】
このような場合の対応としては柱脚連結部のアンカーボルトやベースプレートを剛強にし、柱材の下端部を塑性化させることによって安全性を高めたり、アンカーボルトに伸び性能の良い鋼材を用いてアンカーボルトが塑性化しても破断し難くする等が考えられるが、何れの場合も高度の設計技術と大きな連結部材を要するという問題がある。
【０００７】
また、柱材と基礎杭とが剛に連結された場合、地震の揺れにより柱材から基礎杭に対して曲げモーメントがそのまま伝達されてしまい、基礎杭により曲げモーメントを負担しなければならないため基礎杭を大型化したり複数並設する必要があり、基礎杭工事に多大な労力や工期を要し、工費コストが増大するという問題がある。
【０００８】
また、柱脚部の連結状態を回転変形に対する剛性を極力小さくした構造として特許第3150987号公報に開示された柱脚連結構造が提案されている。その具体的構成は基礎杭に接続されるコンクリートに埋設されたアンカーボルトを角形鋼管柱４辺の線上に配置し、角形鋼管柱の脚部に固定されたベースプレートを該アンカーボルトに対してナットで固定したものである。
【０００９】
このような構造とすることで、従来のように基礎杭に接続されるコンクリートに埋設されたアンカーボルトが角形鋼管柱の外周部に配置され、角形鋼管柱の脚部に固定されたベースプレートを該アンカーボルトに対してナットで固定した場合と比較してアンカーボルトが柱芯により近付いているため、柱脚部の回転変形に対する剛性をより小さくすることが出来、これにより基礎杭が負担する曲げモーメントを軽減し、基礎構造体を簡略化して基礎工事にかかる労力や工期、或いは工費コストを低減することが出来るものである。
【００１０】
【発明が解決しようとする課題】
しかしながら、前述の柱脚部の回転変形に対する剛性をより小さくした構成で十分であるとは言えず、より柱脚部の回転変形に対する剛性を小さくした構成が望まれている。
【００１１】
柱の脚部が回転変形するためには柱下端部のベースプレートが回転する必要があるが、上記構成ではベースプレートの沈下方向や浮き上がり方向に関してはアンカーボルトが角形鋼管柱４辺の線上に配置されるためベースプレートの張り出しが小さくて済むので抵抗は少なく、コンクリートの圧縮変形やベースプレートの曲げ変形で回転は生じる。
【００１２】
しかしながら、ベースプレート下面側には基礎構造体の上面が位置しており、柱芯から角形鋼管柱の辺までの距離が存在するため大きな回転変形を定量的に期待することは困難である。
【００１３】
本発明は前記課題を解決するものであり、その目的とするところは、柱脚の大きな回転変形を定量的に期待することが出来、工場製作が容易で施工現場での施工性にも優れた柱脚連結構造を提供せんとするものである。
【００１４】
【課題を解決するための手段】
前記目的を達成するための本発明に係る柱脚連結構造は、基礎構造体に設けられた棒状連結部材を該基礎構造体に連結される柱の断面略中央部の位置で該基礎構造体の頭部から突出させ、且つ前記基礎構造体の頭部に凸状部を有する下部支持部材を該下部支持部材の凸状部に前記棒状連結部材を挿通した状態で設けると共に、柱の脚部に固定されたベースプレートを固定する平板状の接続部材に前記棒状連結部材を挿通すると共に、該接続部材を前記下部支持部材の凸状部上に回転変形可能な状態で載置し、且つ該接続部材と前記柱の脚部に固定されたベースプレートとを固定することにより柱の脚部と基礎構造体とを連結することを特徴とする。
【００１５】
本発明は、上述の如く構成したので、基礎構造体の頭部に設けられた下部支持部材の凸状部に棒状連結部材を挿通すると共に柱の脚部に固定されたベースプレートを固定する平板状の接続部材に前記棒状連結部材を挿通すると共に、該接続部材を前記下部支持部材の凸状部上に回転変形可能な状態で載置し、且つ該接続部材と前記柱の脚部に固定されたベースプレートとを固定したことで、柱の脚部が回転変形可能な状態で基礎構造体と連結される。これにより、柱脚の大きな回転変形を定量的に期待することが出来、構造が簡単なため工場製作が容易で且つ施工現場での施工性にも優れた柱脚連結構造を提供することが出来る。
【００１６】
また、前記棒状連結部材に上部押さえ部材を設け、前記接続部材の鉛直方向の移動を拘束し、柱の浮き上がり力が該棒状連結部材に伝達されるように構成した場合には、上部押さえ部材により柱の脚部に固定されたベースプレートに固定された接続部材の鉛直方向の移動が拘束されるので柱の脚部と基礎構造体とを確実に連結することが出来る。また、柱の浮き上がり力が棒状連結部材に伝達されるため引抜き荷重に抵抗することが出来る。
【００１７】
また、前記基礎構造体が杭基礎からなり、該杭基礎に直接、前記棒状連結部材を設けた場合には、柱脚部で回転変形が可能なため杭基礎が負担する曲げモーメントを軽減することが出来るため小径の杭基礎を採用することが出来、基礎構造体を簡略化して基礎工事にかかる労力や工期、或いは工費コストを低減することが出来る。
【００１８】
【発明の実施の形態】
図により本発明に係る柱脚連結構造の一実施形態を具体的に説明する。図１は本発明に係る柱脚連結構造を示す断面説明図、図２は下部支持部材と基礎構造体との組付けの様子を示す分解斜視図、図３は接続部材の組付けの様子を示す分解斜視図、図４は柱脚と接続部材との組付けの様子を示す分解斜視図、図５は棒状連結部材を中空鋼管杭の内部に埋設する際にグラウト材を充填する様子を示す斜視図、図６は下部支持部材とレベルキャップの構成を示す断面説明図である。
【００１９】
また、図７は鋼管杭が斜行して設置された場合にレベルキャップにより下部支持部材の水平レベル及び棒状連結部材の鉛直レベルを調整する様子を示す断面説明図、図８は接続部材上に柱脚を載置して固定する際に接続部材を仮固定する様子を示す断面説明図、図９は柱脚が固定された接続部材が地震等の揺れにより回転変形する様子を示す断面説明図である。
【００２０】
また、図10は他の構成のレベルキャップからグラウト材を充填する様子を示す斜視図、図11は図10のレベルキャップに使用される下部支持部材の一例を示す断面説明図、図12は種々の下部支持部材の構成を示す断面説明図、図13は種々の棒状連結部材及び下部支持部材の構成を示す断面説明図である。
【００２１】
また、図14は３本のアンカーボルトを棒状連結部材とした場合の下部支持部材と基礎構造体との組付けの様子を示す分解斜視図、図15は３本のアンカーボルトを棒状連結部材とした場合の接続部材の組付け及び柱脚と接続部材との組付けの様子を示す分解斜視図、図16及び図17は本発明に係る柱脚連結構造が適用出来る各種の基礎構造体の構成を示す断面説明図、図18は柱と棒状連結部材との位置を調整するための他の構成を示す断面説明図、図19は本発明に係る柱脚連結構造が適用出来る他の基礎構造体の構成を示す断面説明図である。
【００２２】
図１は建築物の柱１の脚部と基礎構造体であって杭基礎となる鋼管杭２とを直接連結した柱脚連結構造であって、地盤６に埋設された中空の鋼管杭２の内部に棒状連結部材３の一端部が不定形充填材である無収縮グラウト材やコンクリート或いは膨張コンクリート等の充填材４を充填して硬化することで埋設され、該棒状連結部材３の他端部が鋼管杭２の頭部から柱１の断面略中央部の位置に突出している。
【００２３】
中空の鋼管杭２の内部には棒状連結部材３の埋設端部よりも下側の位置に堰止め部材５が固定されており、充填材４を充填した時に該充填材４が鋼管杭２の下部側へ漏れることを防止している。堰止部材５は鋼管杭２内部に鉄板等を溶接しても良いし、鋼管杭２内部の所定の深さの位置に突起を設けておいて堰止部材５を載置しても良い。堰止部材５としては鉄板の他にメッシュ金網や樹脂プレート、或いは樹脂成形体等を配置して充填材４を堰止めるようにしても良い。
【００２４】
また、充填材４を堰止め得る堰止部材５を鋼管杭２の内部の所定の深さに紐や針金或いは鉄筋等により吊るし下げて鋼管杭２の頭部に引っ掛けておき硬化させることでも良い。尚、堰止部材５を省略して鋼管杭２の内部全体に亘って充填材４を充填するように構成しても良い。
【００２５】
鋼管杭２の中空内面には突起部や凹部或いは錆を発生させて充填材４との固着を増大させることが好ましい。
【００２６】
鋼管杭２の頭部には棒状連結部材３が挿通される孔７ａを有するレベルキャップ７が押さえボルト８により取り付けられており、該レベルキャップ７の上部に棒状連結部材３が挿通される孔９ａを有する下部支持部材９が載置されている。
【００２７】
下部支持部材９には孔９ａに挿通された棒状連結部材３の周囲に凸状部９ｂが形成されており、更に下部支持部材９の凸状部９ｂの上部には棒状連結部材３が挿通される孔10ａを有する接続部材10が載置されている。
【００２８】
更に接続部材10の上部には柱１の脚部に固定され、棒状連結部材３が挿通される孔11ａを有するベースプレート11が載置されている。
【００２９】
柱１は角形鋼管、円形鋼管、組立て柱、二重柱、Ｈ型鋼、Ｉ型鋼等の各種の鉄骨柱で構成することが出来、その柱脚部にベースプレート11が溶接やボルト止め或いは嵌合等により固定されている。柱１がＨ型鋼やＩ型鋼の場合にはフランジを接続するウエブに鋼管杭２の頭部から突出した棒状連結部材３の端部が干渉しない程度の切り欠きを設ければ良い。
【００３０】
ベースプレート11と接続部材10とは高力ボルト等によるボルト止めや溶接、或いは圧着等により固定されている。
【００３１】
図１に示す棒状連結部材３は両端部にネジ部を有するアンカーボルトにより構成されており、鋼管杭２内部に埋設される側の端部にはワッシャー等の定着板12がボルト止めにより固定されている。これにより、棒状連結部材３の充填材４からの引抜き抵抗を付与している。尚、ナット単体だけで引抜き抵抗が十分な場合は定着板12を省略することも出来る。
【００３２】
棒状連結部材３の鋼管杭２の頭部から突出した側の端部には接続部材10の上部にリング状の上部押さえ部材13が棒状連結部材３に挿通して当接されており、上部押さえ部材13は更にその上部に棒状連結部材３のネジ部に螺合締着されたダブルナットにより固定されている。
【００３３】
図２に示すように、棒状連結部材３は、予め工場等でアンカーボルトの一端部に定着板12をボルト止めすると共に他端部に下部支持部材９を挿通してその外側にナット14を螺合したものが製作される。
【００３４】
そして、図７に示すように、中空の鋼管杭２の頭部に設けられたレベルキャップ７の孔７ａに棒状連結部材３を定着板12側から挿入し、下部支持部材９をレベルキャップ７の天端面７ｂに当接して支持させる。
【００３５】
鋼管杭２は地盤６に対して打ち込んだ際に図７に示すように斜行した状態で設置される場合があるため、鋼管杭２に対するレベルキャップ７の嵌め込み深さを調節して該レベルキャップ７の天端面７ｂを基準の水平面に合わせた状態で押さえボルト８を螺合締着してレベルキャップ７を鋼管杭２に固定する。
【００３６】
レベルキャップ７の内周面と鋼管杭２の外周面との間には所定の間隙が設定されており、これにより鋼管杭２が斜行した場合でもレベルキャップ７の天端面７ｂを水平面に設定出来るようになっている。
【００３７】
本実施形態では、３個以上の押さえボルト８によりレベルキャップ７を鋼管杭２に固定した例であるが、溶接等によりレベルキャップ７を鋼管杭２に固定しても良い。棒状連結部材３が挿入された鋼管杭２の内部及びレベルキャップ７の内部にコンクリートやグラウト材等の充填材４が充填されて硬化した後は押さえボルト８により固定されたレベルキャップ７と鋼管杭２との固定部には大きな力は加わらないため種々の仮設的な固定方法を採用すれば良い。
【００３８】
図２に示すように、中空の鋼管杭２に固定されたレベルキャップ７の天端面７ｂには、予め測量により求められた柱１の芯（柱１の断面中央部の位置）を示す墨入れ７ｅを施しておく。
【００３９】
そして、棒状連結部材３を柱１の芯（柱１の断面中央部の位置）に位置合せする際には下部支持部材９をレベルキャップ７の天端面７ｂ上でスライドさせて、下部支持部材９の外周面に予め形成された位置決めマーク９ｃとレベルキャップ７の天端面７ｂに形成した墨入れ７ｅとの位置合せを行なうことで棒状連結部材３を柱１の芯に設定することが容易に出来る。
【００４０】
図６に示すように、本実施形態の下部支持部材９は円盤状の板をプレス成型等により凸状部９ｂを形成したものである。レベルキャップ７の天端面７ｂ及び下部支持部材９の凸状部９ｂの所定位置には充填材４を充填するための充填口７ｃ，９ｄが形成されており、図５（ａ），（ｂ）に示すように充填材４を充填するためのロート15ａ，15ｂを利用して各充填口７ｃ，９ｄから充填材４を充填し、図６に示すように鋼管杭２、レベルキャップ７及び下部支持部材９の内部に隙間無く充填材４を充填する。
【００４１】
充填材４が硬化した段階で棒状連結部材３の落下を防止するために棒状連結部材３の上端部のネジ部に螺合したナット14を取り外した後、図３に示すように、下部支持部材９の凸状部９ｂの上部に接続部材10の中央部に形成された孔10ａを棒状連結部材３に挿通して該接続部材10を載置する。
【００４２】
そして、接続部材10の上部にリング状の上部押さえ部材13を棒状連結部材３に挿通して載置し、前述の取り外したナット14を螺合締着し、更に別のナットを螺合締着してダブルナットにより締着固定する。
【００４３】
そして、図４に示すように、接続部材10の上部に、柱１の脚部に固定されたベースプレート11の中央部に設けられた孔11ａを棒状連結部材３に挿通して該ベースプレート11を載置し、柱１の外周部の４隅に設けられたベースプレート11の各ボルト孔及び接続部材10の４隅に設けられた各ボルト孔に夫々ボルトを挿通し、ナットを螺合締着して接続部材10とベースプレート11とがボルト止めにより固定される。尚、接続部材10とベースプレート11とはボルト止め以外にも溶接等により固定されても良い。
【００４４】
接続部材10は下部支持部材９の凸状部９ｂ上で回転変形可能に配置されているため、接続部材10にベースプレート11を固定する際には、図８に示すように、予めレベルキャップ７の天端面７ｂと接続部材10の下面との間に少なくとも３組の組みキャンバー16ａ，16ｂを設置して接続部材10を仮固定し、その上部に柱１の脚部に固定されたベースプレート11を載置して固定すれば安定して固定作業を行なうことが出来る。
【００４５】
接続部材10とベースプレート11との固定が完了したら組みキャンバー16ａ，16ｂを除去し、接続部材10、ベースプレート11及び柱１が一体的に回転変形可能に構成される。
【００４６】
上記構成において、鋼管杭２の頭部に設けられた下部支持部材９の凸状部９ｂ上に柱１の脚部に固定されたベースプレート11に固定された接続部材10が回転変形可能な状態で配置され、該接続部材10が鋼管杭２の内部に埋設された棒状連結部材３に挿通されたことで、柱１の脚部が回転変形可能な状態で鋼管杭２と連結される。これにより、地震等により揺れが生じた場合には、図９に示すように、柱脚の大きな回転変形を定量的に期待することが出来る。
【００４７】
図９は地震等により柱１に取り付けられた上部フレームが図９の右側へ変形しようとした時の様子を示す。この場合、柱脚部には図９の右側に移動しようとする剪断力と鉛直上方への引っ張り力、或いは圧縮力が加わりながら回転変形が生じる。この引っ張り力により棒状連結部材３に引抜き力が発生する。
【００４８】
更に接続部材10が下部支持部材９と上部押さえ部材13との間で回転しようとした際に付加的に棒状連結部材３への引抜き力が発生し、これ等の引抜き力が総合されて棒状連結部材３に加わる。
【００４９】
棒状連結部材３が鋼管杭２内部から抜け出そうとする力は棒状連結部材３周囲の充填材４の付着力や棒状連結部材３の下端部の定着板12やナット等の充填材４に対する定着力によって充填材４に伝達される。
【００５０】
充填材４をグラウト材やコンクリート等のように強固なものを用いれば、棒状連結部材３が鋼管杭２内部から抜け出そうとする力を鋼管杭２に伝達することが出来る。
【００５１】
充填材４が上側へ抜け出そうとする力を鋼管杭２に伝達するためには、鋼管杭２の内面と充填材４との付着力に期待することが出来るが、更に大きな引抜き力に抵抗する必要がある場合には鋼管杭２の内面に凹凸を設けて引っ掛かり効果を向上することが出来る。
【００５２】
例えば、鋼管杭２の内面に錆を発生させたり鋼管杭２の内面に鉄筋やプレートを溶接したり、予め凹凸を有する縞鋼板等のプレートで鋼管杭２を作製したり、予め鋼管杭２の外面側からビスを打ち込んで内面に突起部を設けたり、更には棒状連結部材３の下端部と鋼管杭２とを鉄筋やプレートで連結して直接引抜き力を伝達するように構成しても良い。
【００５３】
尚、下部支持部材９を介して伝達される圧縮力に関しても充填材４から鋼管杭２へ力が伝達されるがその伝達手段としても前述と同様に構成することが出来る。また、鋼管杭２内部の堰止部材５を鋼管杭２に固定して圧縮力の伝達効果を期待することも出来る。
【００５４】
また、図９の右側に移動しようとする剪断力と鉛直下方に押し付ける圧縮力が加わりながら回転変形が生じた場合、圧縮力は柱１→ベースプレート11→接続部材10→下部支持部材９→充填材４→鋼管杭２→地盤６の順に伝達され棒状連結部材３には直接的な力は加わらない。
【００５５】
但し、棒状連結部材３には前述の接続部材10の回転に伴う付加的な引っ張り力が加わり且つ水平方向への剪断力も加わる。
【００５６】
上記柱脚連結構造では、構造が簡単なため各部品の工場製作が容易で且つ施工現場での施工性にも優れる。
【００５７】
また、上部押さえ部材13により柱１の脚部に固定されたベースプレート11に固定された接続部材10の鉛直方向の移動が拘束されるので柱１の脚部と鋼管杭２とを確実に連結することが出来る。また、浮き上がり力が棒状連結部材３に伝達されるため引抜き荷重に抵抗することが出来る。
【００５８】
また、基礎構造体として杭基礎となる鋼管杭２を採用したことで、柱脚部で回転変形が可能なため鋼管杭２が負担する曲げモーメントを軽減することが出来、これに伴い小径の鋼管杭２を採用することが出来、基礎構造体を簡略化して基礎工事にかかる労力や工期、或いは工費コストを低減することが出来る。
【００５９】
図10及び図11はレベルキャップ７及び下部支持部材９の他の構成を示す図である。本実施形態のレベルキャップ７では、図10（ａ），（ｂ）に示すように、前述したレベルキャップ７の天端面７ｂの円周方向に円弧状のスリットを形成した充填口７ｃに加えて、中央部の孔７ａに連続する径方向のスリットからなる充填口７ｄが下部支持部材９の外径よりも外側まで延長して形成されている。また、本実施形態の下部支持部材９は、図11に示すように、充填口９ｄが省略されている。
【００６０】
そして、ロート15ａを用いて充填口７ｃから充填材４を充填することで、鋼管杭２、レベルキャップ７及び下部支持部材９の下面に充填材４が満たされた後、余分に充填された充填材４が充填口７ｄから溢れ出すことにより下部支持部材９の凸状部９ｂの下部にも隙間無く充填材４を充填して硬化させることが出来る。
【００６１】
図12（ａ）〜（ｃ）は下部支持部材９の他の構成を示す図である。図12（ａ）は下部支持部材９の凸状部９ｂが溶接や切削等により肉厚に形成された場合の一例であり、図12（ｂ）は平板状の下部支持部材９の上部に別体のリング状部材17を載置して凸状部としたものである。また、図12（ｃ）は平板状の下部支持部材９の上部にナット14をそのまま残してこのナット14を凸状部として利用するものである。
【００６２】
これ等の各下部支持部材９の構成でも前述と同様な効果を得ることが出来るものである。
【００６３】
また、図13（ａ）は棒状連結部材３として異形鉄筋棒を利用し、その棒状連結部材３を２本配置した場合の一例であって下部支持部材９には２本の棒状連結部材３を挿通する２つの孔が形成されている。また、図13（ｂ）は鋼管杭２の頭部にプレート18等を溶接し、更にボルト19をスタッド溶接して立設固定した場合の一例である。そして、ボルト19に下部支持部材９が挿通されて前述と同様に構成される。
【００６４】
また、図13（ｃ）はレベルキャップ７の中央部に形成された孔７ａにワッシャ20を介してボルト19が挿通され、更にワッシャ20を介してナット14が螺合締着される。そして、レベルキャップ７が鋼管杭２に溶接される。ナット14が下部支持部材の凸状部として構成される。図13（ｂ），（ｃ）に示すボルト19は比較的高強度の材料とすることが望ましい。
【００６５】
図14及び図15は柱１が比較的大きい場合の一例であって、棒状連結部材３を３本配置しており、下部支持部材９には３本の棒状連結部材３を挿通する３つの孔が形成されている。この３つの孔は前述と同様な貫通孔で、棒状連結部材３を挿通し、図示しないナットにより棒状連結部材３の落下を防止するような構成としている。
【００６６】
図14に示すように棒状連結部材３を中空の鋼管杭２の内部に挿入して前述したように充填口７ｃ，９ｄから充填材４を充填して硬化させ、図15に示すように、接続部材10の中央部に形成された孔10ａに棒状連結部材３を挿通して該接続部材10を下部支持部材９の凸状部９ｂの上部に載置し、更にその上から円盤状の上部押さえ部材13の孔13ａに棒状連結部材３を挿通して接続部材10の上部に上部押さえ部材13を載置してナット14を各棒状連結部材３に螺合締着して固定する。
【００６７】
そして、接続部材10の上部に、柱１の脚部に固定されたベースプレート11の中央部に設けられた孔11ａに棒状連結部材３を挿通して該ベースプレート11を載置し、柱１の外周部の４辺部に設けられたベースプレート11の各ボルト孔及び接続部材10の４辺部に設けられた各ボルト孔に夫々図示しないボルトを挿通し、ナットを螺合締着して接続部材10とベースプレート11とがボルト止めにより固定される。尚、接続部材10とベースプレート11とはボルト止め以外にも溶接等により固定されても良い。他の構成は前述と同様に構成されて同様の効果を得ることが出来る。
【００６８】
図16は基礎構造体の他の構成を示す図である。図16（ａ）はＰＣ（プレキャストコンクリート）杭20の中空部に鋼管杭２が埋設された基礎構造体であり、図16（ｂ）は地盤６を改良した地盤改良体21の内部に鋼管杭２が埋設された基礎構造体である。
【００６９】
また、図16（ｃ）は鋼管杭２の上部周囲を大径の鋼管22で補強した基礎構造体であり、これ等図16（ａ）〜（ｃ）に示す基礎構造体は鋼管杭２の剪断抵抗向上対策に効果的である。また、図16（ｄ）は鋼管の内部にコンクリートが設けられた中空の鋼管コンクリート杭（ＳＣ杭）23、図16（ｅ）は中空のコンクリート杭（ＰＨＣ杭）24を夫々基礎構造体とした一例である。他の構成は前述と同様に構成されて同様の効果を得ることが出来る。
【００７０】
また、図17は地盤６内に埋設されるＲＣ（鉄筋コンクリート）基礎25に棒状連結部材３及び下部支持部材９を取り付けた場合の一例を示す。図17（ａ）ではＲＣ基礎25のコンクリートを打設する前に予め棒状連結部材３を補強鉄筋26或いは図示しない型枠等により支持させて配置しておき、コンクリートを打設して硬化した後、ＲＣ基礎25の頭部に下部支持部材９の中央部に形成された孔９ａに棒状連結部材３を挿通して該下部支持部材９を載置する。
【００７１】
また、図17（ｂ）では既設のＲＣ基礎25の頭部に棒状連結部材３を挿入して固着させ、ＲＣ基礎25の頭部に下部支持部材９の中央部に形成された孔９ａに棒状連結部材３を挿通して該下部支持部材９を載置する。他の構成は前述と同様に構成されて同様の効果を得ることが出来る。
【００７２】
また、図18は柱１と棒状連結部材３との位置を調整するための他の構成を示す断面説明図であり、柱１の脚部に固定されたベースプレート11に大径の孔若しくは切り欠き部からなる位置調整領域11ｂが形成されており、接続部材10のボルト孔、ベースプレート11の位置調整領域11ｂ及び固定補助板27のボルト孔にボルトが挿通され、ナットを螺合締着することで、位置調整領域11ｂを利用して柱１と棒状連結部材３との位置合せを行なってボルト止めすることが出来る。
【００７３】
接続部材10とベースプレート11とを固定した後は固定補助板27に形成された充填口27ａからグラウト材等の充填材４を充填して位置調整領域11ｂに満たして硬化させる。
【００７４】
図19は地盤６上に布設される基礎コンクリート（以下、「布基礎28」という）の頭部に棒状連結部材３及び下部支持部材９を取り付けて柱１を連結した場合の一例を示す。布基礎28は地盤６上に割栗石29が敷設され、更に割栗石29の上部にコンクリート30が打設され、更にその上部に布基礎28が打設されている。
【００７５】
布基礎28のコンクリートを打設する前に予め棒状連結部材３を内部に配筋される図示しない補強鉄筋或いは型枠等により支持させて配置しておき、コンクリートを打設して硬化した後、布基礎28の頭部に下部支持部材９の中央部に形成された孔９ａに棒状連結部材３を挿通して該下部支持部材９を載置する。他の構成は前述の図１と同様に構成され、同様の効果を得ることが出来る。
【００７６】
【発明の効果】
本発明は、上述の如き構成と作用とを有するので、基礎構造体の頭部に設けられた下部支持部材の凸状部に棒状連結部材を挿通すると共に柱の脚部に固定されたベースプレートと固定する接続部材を回転変形可能な状態で配置したことで、柱の脚部が回転変形可能な状態で基礎構造体と連結される。これにより、柱脚の大きな回転変形を定量的に期待することが出来、構造が簡単なため工場製作が容易で且つ施工現場での施工性にも優れた柱脚連結構造を提供することが出来る。
【００７７】
また、棒状連結部材に上部押さえ部材を設け、接続部材の鉛直方向の移動を拘束し、柱の浮き上がり力が該棒状連結部材に伝達されるように構成した場合には、上部押さえ部材により柱の脚部に固定されたベースプレートに固定された接続部材の鉛直方向の移動が拘束されるので柱の脚部と基礎構造体とを確実に連結することが出来る。また、柱の浮き上がり力が棒状連結部材に伝達されるため引抜き荷重に抵抗することが出来る。
【００７８】
また、基礎構造体が杭基礎からなり、該杭基礎に直接、棒状連結部材を設けた場合には、柱脚部で回転変形が可能なため杭基礎が負担する曲げモーメントを軽減することが出来るため小径の杭基礎を採用することが出来、基礎構造体を簡略化して基礎工事にかかる労力や工期、或いは工費コストを低減することが出来る。
【図面の簡単な説明】
【図１】本発明に係る柱脚連結構造を示す断面説明図である。
【図２】下部支持部材と基礎構造体との組付けの様子を示す分解斜視図である。
【図３】接続部材の組付けの様子を示す分解斜視図である。
【図４】柱脚と接続部材との組付けの様子を示す分解斜視図である。
【図５】棒状連結部材を中空鋼管杭の内部に埋設する際にグラウト材を充填する様子を示す斜視図である。
【図６】下部支持部材とレベルキャップの構成を示す断面説明図である。
【図７】鋼管杭が斜行して設置された場合にレベルキャップにより下部支持部材の水平レベル及び棒状連結部材の鉛直レベルを調整する様子を示す断面説明図である。
【図８】接続部材上に柱脚を載置して固定する際に接続部材を仮固定する様子を示す断面説明図である。
【図９】柱脚が固定された接続部材が地震等の揺れにより回転変形する様子を示す断面説明図である。
【図10】他の構成のレベルキャップからグラウト材を充填する様子を示す斜視図である。
【図11】図10のレベルキャップに使用される下部支持部材の一例を示す断面説明図である。
【図12】種々の下部支持部材の構成を示す断面説明図である。
【図13】種々の棒状連結部材及び下部支持部材の構成を示す断面説明図である。
【図14】３本のアンカーボルトを棒状連結部材とした場合の下部支持部材と基礎構造体との組付けの様子を示す分解斜視図である。
【図15】３本のアンカーボルトを棒状連結部材とした場合の接続部材の組付け及び柱脚と接続部材との組付けの様子を示す分解斜視図である。
【図16】本発明に係る柱脚連結構造が適用出来る各種の基礎構造体の構成を示す断面説明図である。
【図17】本発明に係る柱脚連結構造が適用出来る各種の基礎構造体の構成を示す断面説明図である。
【図18】柱と棒状連結部材との位置を調整するための他の構成を示す断面説明図である。
【図19】本発明に係る柱脚連結構造が適用出来る他の基礎構造体の構成を示す断面説明図である。
【符号の説明】
１…柱
２…鋼管杭
３…棒状連結部材
４…充填材
５…堰止部材
６…地盤
７…レベルキャップ
７ａ…孔
７ｂ…天端面
７ｃ，７ｄ…充填口
７ｅ…墨入れ
８…押さえボルト
９…下部支持部材
９ａ…孔
９ｂ…凸状部
９ｃ…位置決めマーク
９ｄ…充填口
10…接続部材
10ａ…孔
11…ベースプレート
11ａ…孔
11ｂ…位置調整領域
12…定着板
13…上部押さえ部材
13ａ…孔
14…ナット
15ａ，15ｂ…ロート
16ａ，16ｂ…組みキャンバー
17…リング状部材
18…プレート
19…ボルト
20…ＰＣ杭
21…地盤改良体
22…鋼管
23…ＳＣ杭
24…ＰＨＣ杭
25…ＲＣ基礎
26…補強鉄筋
27…固定補助板
27ａ…充填口
28…布基礎
29…割栗石
30…コンクリート[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a column base connection structure in which a leg portion of a building and a foundation structure are connected, and in particular, in a column base connection structure of a medium- and low-rise steel structure, a state where rigidity against rotational deformation of the column base is low. It is related with the column base connection structure which connected the leg part of the column and the foundation structure.
[0002]
[Prior art]
Conventionally, as a method of fixing a steel column leg to a foundation structure formed of reinforced concrete or the like, it is common to fix a base plate fixed to a column lower end to an anchor bolt or the like embedded in the foundation structure. .
[0003]
In general, the base plate projects largely around the periphery of the column base, and the anchor bolts are arranged substantially evenly with respect to the cross section of the column material on the surface of the projecting base plate.
[0004]
According to such a column base connection structure, even if the column leg is rotated by an external force such as an earthquake, the anchor bolt pulls in the lifting direction of the base plate, and the foundation structure compresses in the sinking direction of the base plate. A large rotational resistance is generated, and the deformation of the upper steel frame can be suppressed.
[0005]
Such a conventional column base connection structure has the feature that the deformation at the time of a middle earthquake can be reduced even if the cross section of the column material or the upper beam material is small, but the column base part is not in a large earthquake. There is also a risk of plasticizing and breaking.
[0006]
In such cases, the anchor bolts and base plate of the column base connecting part are made strong and the lower end of the column material is plasticized to improve safety, or the anchor bolt is anchored using a steel material with good elongation performance. It is conceivable that even if the bolt is plasticized, it is difficult to break, but in any case, there is a problem that a high-level design technique and a large connecting member are required.
[0007]
In addition, when the column and the foundation pile are rigidly connected, the bending moment is transmitted as it is from the column to the foundation pile due to the shaking of the earthquake, and the foundation pile must bear the bending moment. There is a problem that the piles need to be enlarged or arranged in parallel, and the foundation pile work requires a lot of labor and work period, and the construction cost increases.
[0008]
Further, a column base connection structure disclosed in Japanese Patent No. 3150987 has been proposed as a structure in which the connection state of the column base is made as small as possible with respect to rotational deformation. Specifically, the anchor bolts embedded in the concrete connected to the foundation pile are arranged on the four sides of the square steel pipe column, and the base plate fixed to the legs of the square steel pipe column is attached to the anchor bolt with a nut. It is fixed.
[0009]
With such a structure, the anchor bolts embedded in the concrete connected to the foundation pile as in the prior art are arranged on the outer periphery of the square steel pipe column, and the base plate fixed to the legs of the square steel pipe column is attached to the base plate. Compared with the case where the anchor bolt is fixed with a nut, the anchor bolt is closer to the column core, so that the rigidity against the rotational deformation of the column base can be reduced, and this causes the bending moment that the foundation pile bears. It is possible to reduce the labor, the construction period, or the construction cost for the foundation work by reducing the cost and the basic structure.
[0010]
[Problems to be solved by the invention]
However, it cannot be said that the above-described configuration in which the rigidity with respect to the rotational deformation of the column base is further reduced, and a configuration in which the rigidity with respect to the rotational deformation of the column base is further reduced is desired.
[0011]
The base plate at the lower end of the column needs to be rotated in order for the column leg to rotate and deform. However, in the above configuration, the anchor bolts are arranged on the lines of the four sides of the square steel pipe column in the sinking direction and the lifting direction of the base plate. For this reason, since the overhang of the base plate is small, the resistance is low, and the rotation occurs due to the compressive deformation of the concrete or the bending deformation of the base plate.
[0012]
However, since the upper surface of the foundation structure is located on the lower surface side of the base plate and there is a distance from the column core to the side of the square steel pipe column, it is difficult to quantitatively expect large rotational deformation.
[0013]
The present invention solves the above-mentioned problems, and the object of the present invention is to quantitatively expect a large rotational deformation of the column base, which is easy to manufacture at the factory and excellent in workability at the construction site. It is intended to provide a column base connection structure.
[0014]
[Means for Solving the Problems]
In order to achieve the above-mentioned object, the column base connection structure according to the present invention includes a rod-like connection member provided in the foundation structure at a position substantially at the center of the cross section of the column connected to the foundation structure. A lower support member that protrudes from the head and has a convex portion on the head of the foundation structure The Insert the rod-shaped connecting member into the convex part of the lower support member Provided in the state As , Base plate fixed to column leg The Fix Flat Connecting member And inserting the connecting member on the convex part of the lower support member. In a state where it can be rotated and deformed Listed And connecting the connecting member and the base plate fixed to the leg portion of the column to connect the leg portion of the column and the foundation structure.
[0015]
Since the present invention is configured as described above, the base plate is inserted into the convex portion of the lower support member provided at the head of the foundation structure and fixed to the leg portion of the column. The Fix Flat Connecting member And inserting the connecting member on the convex part of the lower support member. In a state where it can be rotated and deformed Listed Place And fixing the connecting member and a base plate fixed to the leg portion of the column. As a result, the leg portion of the column is connected to the foundation structure in a state in which it can rotate and deform. As a result, large rotational deformation of the column base can be expected quantitatively, and since the structure is simple, it is possible to provide a column base connection structure that is easy to manufacture at the factory and excellent in workability at the construction site. .
[0016]
In addition, when the upper pressing member is provided on the rod-shaped connecting member, the vertical movement of the connecting member is restricted, and the lifting force of the column is transmitted to the rod-shaped connecting member, the upper pressing member Since the vertical movement of the connecting member fixed to the base plate fixed to the column leg is restricted, the column leg and the foundation structure can be reliably connected. Further, since the lifting force of the column is transmitted to the rod-like connecting member, it is possible to resist the drawing load.
[0017]
Further, when the foundation structure is a pile foundation and the rod-like connecting member is provided directly on the pile foundation, the bending moment that the pile foundation bears can be reduced because the column base can be rotationally deformed. Therefore, it is possible to adopt a small-diameter pile foundation, simplify the foundation structure, and reduce labor, construction period, or construction cost for foundation work.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of a column base connecting structure according to the present invention will be described specifically with reference to the drawings. FIG. 1 is a cross-sectional explanatory view showing a column base connecting structure according to the present invention, FIG. 2 is an exploded perspective view showing an assembly state of a lower support member and a foundation structure, and FIG. 3 is an assembly state of a connection member. FIG. 4 is an exploded perspective view showing how the column base and the connecting member are assembled. FIG. 5 shows how the grout material is filled when the rod-like connecting member is embedded in the hollow steel pipe pile. FIG. 6 is a cross-sectional explanatory view showing the structure of the lower support member and the level cap.
[0019]
FIG. 7 is a cross-sectional explanatory view showing a state in which the horizontal level of the lower support member and the vertical level of the rod-like connecting member are adjusted by the level cap when the steel pipe pile is installed obliquely, and FIG. 8 is on the connecting member. Cross-sectional explanatory diagram showing how the connection member is temporarily fixed when the column base is placed and fixed, FIG. 9 is a cross-sectional explanatory diagram illustrating the state where the connection member to which the column base is fixed is rotated and deformed by an earthquake or the like It is.
[0020]
FIG. 10 is a perspective view showing a state in which grout material is filled from a level cap of another configuration, FIG. 11 is a cross-sectional explanatory view showing an example of a lower support member used in the level cap of FIG. 10, and FIG. FIG. 13 is an explanatory cross-sectional view showing the configuration of various rod-like connecting members and the lower support member.
[0021]
FIG. 14 is an exploded perspective view showing the state of assembling the lower support member and the foundation structure when three anchor bolts are used as rod-shaped connecting members, and FIG. 15 is a diagram showing three anchor bolts connected to the rod-shaped connecting members. FIG. 16 and FIG. 17 are configurations of various foundation structures to which the column base connecting structure according to the present invention can be applied. FIG. 18 is a cross-sectional explanatory view showing another configuration for adjusting the position of the column and the rod-like connecting member, and FIG. 19 is another foundation structure to which the column base connecting structure according to the present invention can be applied. It is a section explanatory view showing the composition.
[0022]
FIG. 1 shows a column base connection structure in which a leg portion of a building pillar 1 and a steel pipe pile 2 which is a foundation structure and a pile foundation are directly connected, and a hollow steel pipe pile 2 embedded in the ground 6 is shown. One end of the rod-like connecting member 3 is embedded by filling and curing a filler 4 such as non-shrink grout material, concrete, or expanded concrete, which is an irregular shaped filler, and the other end of the rod-like connecting member 3 Projecting from the head of the steel pipe pile 2 to the position of the substantially central portion of the cross section of the column 1.
[0023]
Inside the hollow steel pipe pile 2, a dam member 5 is fixed at a position below the embedded end of the rod-like connecting member 3, and when the filler 4 is filled, the filler 4 Prevents leakage to the lower side. The dam member 5 may be formed by welding a steel plate or the like inside the steel pipe pile 2 or may be provided with a protrusion provided at a predetermined depth in the steel pipe pile 2. As the dam member 5, in addition to the iron plate, a mesh wire net, a resin plate, a resin molded body, or the like may be disposed to dam the filler 4.
[0024]
Further, the damming member 5 capable of damming the filler 4 may be hung and hung at a predetermined depth inside the steel pipe pile 2 by a string, a wire, a reinforcing bar or the like and hooked on the head of the steel pipe pile 2 to be cured. . In addition, you may comprise so that the weir member 5 may be abbreviate | omitted and the filler 4 may be filled over the whole inside of the steel pipe pile 2. FIG.
[0025]
It is preferable to increase the adhesion with the filler 4 by generating protrusions, recesses or rust on the hollow inner surface of the steel pipe pile 2.
[0026]
A level cap 7 having a hole 7a through which the rod-like connecting member 3 is inserted is attached to the head portion of the steel pipe pile 2 by a holding bolt 8, and a hole 9a through which the rod-like connecting member 3 is inserted above the level cap 7. A lower support member 9 having the above is placed.
[0027]
The lower support member 9 is formed with a convex portion 9b around the rod-like connecting member 3 inserted through the hole 9a, and the rod-like connecting member 3 is inserted above the convex portion 9b of the lower support member 9. A connecting member 10 having a hole 10a is placed.
[0028]
Further, a base plate 11 having a hole 11a through which the rod-like connecting member 3 is inserted is mounted on the upper portion of the connecting member 10.
[0029]
Column 1 can be composed of various steel columns such as square steel tube, round steel tube, assembled column, double column, H-shaped steel, I-shaped steel, etc. Base plate 11 is welded, bolted or fitted to the column base It is fixed by. In the case where the column 1 is H-shaped steel or I-shaped steel, the web connecting the flanges may be provided with a cutout that does not interfere with the end of the rod-like connecting member 3 protruding from the head of the steel pipe pile 2.
[0030]
The base plate 11 and the connecting member 10 are fixed by bolting with a high-strength bolt or the like, welding, or crimping.
[0031]
The rod-shaped connecting member 3 shown in FIG. 1 is composed of anchor bolts having threaded portions at both ends, and a fixing plate 12 such as a washer is fixed to the end portion embedded in the steel pipe pile 2 by bolting. ing. Thereby, the pulling-out resistance from the filler 4 of the rod-shaped connection member 3 is provided. Note that the fixing plate 12 can be omitted when the pull-out resistance is sufficient with the nut alone.
[0032]
A ring-shaped upper pressing member 13 is inserted into and contacted with the upper portion of the connecting member 10 at the end of the rod-shaped connecting member 3 on the side protruding from the head of the steel pipe pile 2. The member 13 is further fixed to the upper portion thereof by a double nut screwed to the screw portion of the rod-like connecting member 3.
[0033]
As shown in FIG. 2, the rod-like connecting member 3 is bolted to one end of an anchor bolt in advance at a factory or the like, and the lower support member 9 is inserted into the other end and a nut 14 is screwed outside. The combined product is produced.
[0034]
Then, as shown in FIG. 7, the rod-like connecting member 3 is inserted from the fixing plate 12 side into the hole 7 a of the level cap 7 provided at the head of the hollow steel pipe pile 2, and the lower support member 9 is attached to the level cap 7. The top end surface 7b is abutted and supported.
[0035]
Since the steel pipe pile 2 may be installed in a skewed state as shown in FIG. 7 when driven into the ground 6, the level cap 7 is adjusted by adjusting the fitting depth of the level cap 7 to the steel pipe pile 2. The level cap 7 is fixed to the steel pipe pile 2 by screwing and fastening the holding bolt 8 in a state where the top end surface 7b of 7 is aligned with the reference horizontal plane.
[0036]
A predetermined gap is set between the inner peripheral surface of the level cap 7 and the outer peripheral surface of the steel pipe pile 2, so that the top end surface 7b of the level cap 7 is set to a horizontal plane even when the steel pipe pile 2 is skewed. It can be done.
[0037]
In the present embodiment, the level cap 7 is fixed to the steel pipe pile 2 with three or more holding bolts 8, but the level cap 7 may be fixed to the steel pipe pile 2 by welding or the like. The level cap 7 and the steel pipe pile fixed by the holding bolt 8 after the inside of the steel pipe pile 2 in which the rod-like connecting member 3 is inserted and the inside of the level cap 7 are filled with the filler 4 such as concrete or grout material and hardened. Since a large force is not applied to the fixing part 2, various temporary fixing methods may be employed.
[0038]
As shown in FIG. 2, on the top end surface 7b of the level cap 7 fixed to the hollow steel pipe pile 2, an inking indicating the core of the column 1 (position of the central portion of the cross section of the column 1) obtained in advance by surveying. 7e is given.
[0039]
Then, when aligning the rod-like connecting member 3 with the core of the column 1 (the position of the central portion of the cross section of the column 1), the lower support member 9 is slid on the top end surface 7b of the level cap 7, and the lower support member 9 By positioning the positioning mark 9c formed in advance on the outer peripheral surface of the metal plate 7 and the inking 7e formed on the top end surface 7b of the level cap 7, the rod-like connecting member 3 can be easily set as the core of the column 1. .
[0040]
As shown in FIG. 6, the lower support member 9 of the present embodiment is formed by forming a convex portion 9b from a disk-shaped plate by press molding or the like. Filling ports 7c and 9d for filling the filler 4 are formed at predetermined positions on the top end surface 7b of the level cap 7 and the convex portion 9b of the lower support member 9, and FIGS. 5 (a) and 5 (b). As shown in FIG. 6, the filler 4 is filled from the filling ports 7c and 9d using the funnels 15a and 15b for filling the filler 4, and the steel pipe pile 2, the level cap 7 and the lower support are shown in FIG. The filler 4 is filled into the member 9 without any gap.
[0041]
In order to prevent the rod-like connecting member 3 from dropping when the filler 4 is hardened, the nut 14 screwed into the threaded portion at the upper end of the rod-like connecting member 3 is removed, and then, as shown in FIG. A hole 10a formed in the central portion of the connecting member 10 is inserted into the upper part of the convex portion 9b of the ninth member 9 and the connecting member 10 is placed.
[0042]
Then, a ring-shaped upper pressing member 13 is inserted through the bar-like connecting member 3 and placed on the upper part of the connecting member 10, the above-mentioned removed nut 14 is screwed and fastened, and another nut is screwed and fastened. Then fasten and fix with a double nut.
[0043]
Then, as shown in FIG. 4, the base plate 11 is mounted on the upper portion of the connecting member 10 by inserting the hole 11 a provided in the central portion of the base plate 11 fixed to the leg portion of the column 1 through the rod-like connecting member 3. The bolts are inserted into the bolt holes of the base plate 11 provided at the four corners of the outer periphery of the column 1 and the bolt holes provided at the four corners of the connecting member 10, respectively, and the nuts are screwed and fastened. The connection member 10 and the base plate 11 are fixed by bolting. The connecting member 10 and the base plate 11 may be fixed by welding or the like other than bolting.
[0044]
Since the connecting member 10 is rotatably arranged on the convex portion 9b of the lower support member 9, when the base plate 11 is fixed to the connecting member 10, as shown in FIG. At least three sets of cambers 16a and 16b are installed between the top end surface 7b and the lower surface of the connection member 10, the connection member 10 is temporarily fixed, and the base plate 11 fixed to the leg portion of the column 1 is mounted on the upper portion. If it is placed and fixed, the fixing work can be performed stably.
[0045]
When the connection member 10 and the base plate 11 are fixed, the assembled cambers 16a and 16b are removed, and the connection member 10, the base plate 11 and the column 1 are configured to be integrally rotatable and deformable.
[0046]
In the above configuration, the connecting member 10 fixed to the base plate 11 fixed to the leg portion of the column 1 on the convex portion 9b of the lower support member 9 provided on the head of the steel pipe pile 2 is in a state in which the connecting member 10 can be rotationally deformed. The connecting member 10 is inserted into the rod-like connecting member 3 embedded in the steel pipe pile 2 so that the column 1 Are connected to the steel pipe pile 2 in a state in which the leg portion can be rotationally deformed. Thereby, when a shake occurs due to an earthquake or the like, a large rotational deformation of the column base can be quantitatively expected as shown in FIG.
[0047]
FIG. 9 shows a state where the upper frame attached to the column 1 is deformed to the right side of FIG. 9 due to an earthquake or the like. In this case, the column base part is subjected to rotational deformation while applying a shearing force to move to the right side of FIG. 9 and a pulling force or a compressing force upward in the vertical direction. A pulling force is generated in the rod-like connecting member 3 by this pulling force.
[0048]
Further, when the connecting member 10 tries to rotate between the lower support member 9 and the upper pressing member 13, an additional pulling force is generated to the bar-shaped connecting member 3, and these pulling forces are combined to form a bar-shaped link. Join the member 3.
[0049]
The force with which the rod-like connecting member 3 tries to escape from the inside of the steel pipe pile 2 is the adhesion force of the filler 4 around the rod-like connecting member 3 and the fixing force of the lower end portion of the rod-like connecting member 3 to the filler 4 such as the fixing plate 12 and nuts. Is transmitted to the filler 4.
[0050]
If a solid material such as grout material or concrete is used as the filler 4, the force that the rod-like connecting member 3 tries to escape from the inside of the steel pipe pile 2 can be transmitted to the steel pipe pile 2.
[0051]
In order to transmit the force that the filler 4 tries to escape upward to the steel pipe pile 2, it can be expected to adhere to the inner surface of the steel pipe pile 2 and the filler 4, but it resists a larger pulling force. When necessary, the hook effect can be improved by providing irregularities on the inner surface of the steel pipe pile 2.
[0052]
For example, rust is generated on the inner surface of the steel pipe pile 2, a reinforcing bar or a plate is welded to the inner surface of the steel pipe pile 2, the steel pipe pile 2 is prepared with a plate such as a striped steel plate having irregularities in advance, A screw may be driven in from the outer surface side to provide a projection on the inner surface, or the lower end portion of the rod-like connecting member 3 and the steel pipe pile 2 may be connected by a reinforcing bar or plate to transmit the pulling force directly. .
[0053]
The compressive force transmitted through the lower support member 9 is also transmitted from the filler 4 to the steel pipe pile 2, but the transmission means can be configured in the same manner as described above. It is also possible to expect the effect of compressive force transmission by fixing the blocking member 5 inside the steel pipe pile 2 to the steel pipe pile 2.
[0054]
In addition, when a rotational deformation occurs while applying a shearing force to move to the right side of FIG. 9 and a compressive force that pushes downward in the vertical direction, the compressive force is the pillar 1 → base plate 11 → connection member 10 → lower support member 9 → filler. It is transmitted in the order of 4 → steel pipe pile 2 → ground 6 and no direct force is applied to the rod-like connecting member 3.
[0055]
However, the bar-like connecting member 3 is subjected to an additional pulling force accompanying the rotation of the connecting member 10 and a shearing force in the horizontal direction.
[0056]
In the above-mentioned column base connection structure, since the structure is simple, it is easy to manufacture each part at the factory and the workability at the construction site is also excellent.
[0057]
Further, since the vertical movement of the connecting member 10 fixed to the base plate 11 fixed to the leg portion of the column 1 is restrained by the upper pressing member 13, the leg portion of the column 1 and the steel pipe pile 2 are reliably connected. I can do it. Further, since the lifting force is transmitted to the rod-like connecting member 3, it is possible to resist the drawing load.
[0058]
In addition, by adopting the steel pipe pile 2 as the pile foundation as the foundation structure, it is possible to reduce the bending moment that the steel pipe pile 2 bears because the column base can be rotated and deformed. The pile 2 can be employed, and the foundation structure can be simplified to reduce the labor, construction period, or construction cost for the foundation work.
[0059]
10 and 11 are diagrams showing another configuration of the level cap 7 and the lower support member 9. In the level cap 7 of the present embodiment, as shown in FIGS. 10A and 10B, in addition to the filling port 7c formed with an arc-shaped slit in the circumferential direction of the top end surface 7b of the level cap 7 described above. A filling port 7d formed of a radial slit continuous with the central hole 7a is formed to extend outward from the outer diameter of the lower support member 9. Further, as shown in FIG. 11, the lower support member 9 of the present embodiment has a filling port 9d omitted.
[0060]
And the filling material 4 is filled from the filling port 7c using the funnel 15a, so that the filling material 4 is filled on the lower surfaces of the steel pipe pile 2, the level cap 7 and the lower support member 9, and then the filling material is filled excessively. When the material 4 overflows from the filling port 7d, the lower portion of the convex portion 9b of the lower support member 9 can be filled and cured without any gap.
[0061]
12A to 12C are diagrams showing another configuration of the lower support member 9. FIG. 12A shows an example in which the convex portion 9b of the lower support member 9 is formed thick by welding or cutting, and FIG. A body-like ring-shaped member 17 is placed to form a convex portion. FIG. 12C shows the use of the nut 14 as a convex portion while leaving the nut 14 as it is at the top of the flat lower support member 9.
[0062]
These configurations of the lower support members 9 can provide the same effects as described above.
[0063]
FIG. 13A is an example in which a deformed reinforcing bar is used as the rod-like connecting member 3 and two rod-like connecting members 3 are arranged. The lower support member 9 has two rod-like connecting members 3. Two holes to be inserted are formed. FIG. 13 (b) shows an example in which a plate 18 or the like is welded to the head of the steel pipe pile 2 and a bolt 19 is stud-welded and fixed upright. Then, the lower support member 9 is inserted into the bolt 19 and configured in the same manner as described above.
[0064]
In FIG. 13C, a bolt 19 is inserted through a washer 20 into a hole 7 a formed at the center of the level cap 7, and a nut 14 is screwed and fastened through the washer 20. Then, the level cap 7 is welded to the steel pipe pile 2. The nut 14 is configured as a convex portion of the lower support member. The bolt 19 shown in FIGS. 13B and 13C is preferably made of a relatively high strength material.
[0065]
14 and 15 show an example in which the column 1 is relatively large, and three rod-like connecting members 3 are arranged, and the lower support member 9 has three holes through which the three rod-like connecting members 3 are inserted. Is formed. These three holes are through-holes similar to those described above, and are configured to pass through the rod-like connecting member 3 and prevent the rod-like connecting member 3 from falling by a nut (not shown).
[0066]
As shown in FIG. 14, the rod-like connecting member 3 is inserted into the hollow steel pipe pile 2, filled with the filler 4 through the filling ports 7c and 9d as described above, and cured, as shown in FIG. The rod-like connecting member 3 is inserted into the hole 10a formed in the central portion of the member 10, the connecting member 10 is placed on the upper portion of the convex portion 9b of the lower support member 9, and a disk-like upper presser is further provided thereon. The bar-like connecting member 3 is inserted into the hole 13a of the member 13, the upper pressing member 13 is placed on the upper part of the connecting member 10, and the nut 14 is screwed and fastened to each bar-like connecting member 3.
[0067]
Then, on the upper part of the connecting member 10, the base plate 11 is placed by inserting the rod-like connecting member 3 into the hole 11 a provided in the center portion of the base plate 11 fixed to the leg portion of the column 1, and the outer periphery of the column 1. A bolt (not shown) is inserted into each of the bolt holes of the base plate 11 provided on the four sides of the part and each of the bolt holes provided on the four sides of the connecting member 10, and the nut is screwed and fastened to connect the connecting member 10. And the base plate 11 are fixed by bolting. The connecting member 10 and the base plate 11 may be fixed by welding or the like other than bolting. Other configurations are the same as described above, and the same effects can be obtained.
[0068]
FIG. 16 is a diagram showing another configuration of the foundation structure. 16 (a) shows a foundation structure in which a steel pipe pile 2 is embedded in the hollow part of a PC (precast concrete) pile 20, and FIG. 16 (b) shows a steel pipe pile inside a ground improvement body 21 improved from the ground 6. Reference numeral 2 denotes an embedded foundation structure.
[0069]
FIG. 16 (c) shows a foundation structure in which the upper periphery of the steel pipe pile 2 is reinforced with a large diameter steel pipe 22. The foundation structure shown in FIGS. Effective for improving shear resistance. 16 (d) shows a hollow steel pipe concrete pile (SC pile) 23 in which concrete is provided inside the steel pipe, and FIG. 16 (e) shows a hollow concrete pile (PHC pile) 24 as a foundation structure. It is an example. Other configurations are the same as described above, and the same effects can be obtained.
[0070]
FIG. 17 shows an example of the case where the rod-like connecting member 3 and the lower support member 9 are attached to an RC (reinforced concrete) foundation 25 embedded in the ground 6. In FIG. 17 (a), before the concrete of the RC foundation 25 is placed, the rod-like connecting member 3 is previously supported by a reinforcing bar 26 or a formwork (not shown), and the concrete is placed and hardened. The rod-like connecting member 3 is inserted into the hole 9a formed in the center of the lower support member 9 in the head of the RC base 25, and the lower support member 9 is placed.
[0071]
17B, the rod-like connecting member 3 is inserted and fixed to the head of the existing RC foundation 25, and the hole 9a formed in the central portion of the lower support member 9 is sticked to the head of the RC foundation 25. The lower support member 9 is placed through the connecting member 3. Other configurations are the same as described above, and the same effects can be obtained.
[0072]
FIG. 18 is a cross-sectional explanatory view showing another configuration for adjusting the positions of the pillar 1 and the rod-like connecting member 3. A large-diameter hole or notch is formed in the base plate 11 fixed to the leg portion of the pillar 1. A position adjustment region 11b is formed, and a bolt is inserted into the bolt hole of the connection member 10, the position adjustment region 11b of the base plate 11, and the bolt hole of the auxiliary fixing plate 27, and the nut is screwed and fastened. By using the position adjustment region 11b, the column 1 and the rod-like connecting member 3 can be aligned and bolted.
[0073]
After the connection member 10 and the base plate 11 are fixed, the filler 4 such as a grout material is filled from the filling port 27a formed in the auxiliary fixing plate 27 to fill the position adjustment region 11b and harden.
[0074]
FIG. 19 shows an example in which the column 1 is connected by attaching the rod-like connecting member 3 and the lower support member 9 to the head of foundation concrete (hereinafter referred to as “fabric foundation 28”) laid on the ground 6. The fabric foundation 28 has a split stone 29 laid on the ground 6, a concrete 30 is placed on the top of the split stone 29, and a fabric foundation 28 is placed on the top.
[0075]
Before placing the concrete of the fabric foundation 28, the rod-like connecting member 3 is previously supported by a reinforcing reinforcing bar or a formwork (not shown) placed inside, placed and hardened by placing the concrete, The rod-like connecting member 3 is inserted into a hole 9a formed in the central portion of the lower support member 9 in the head of the fabric base 28, and the lower support member 9 is placed. Other configurations are the same as those in FIG. 1, and the same effects can be obtained.
[0076]
【The invention's effect】
Since the present invention has the above-described configuration and operation, the base plate includes a rod-like connecting member inserted into the convex portion of the lower support member provided at the head of the foundation structure and fixed to the leg portion of the column. By arranging the connecting member to be fixed in a state in which it can be rotationally deformed, the leg portion of the column is coupled to the foundation structure in a state in which it can be rotationally deformed. As a result, large rotational deformation of the column base can be expected quantitatively, and since the structure is simple, it is possible to provide a column base connection structure that is easy to manufacture at the factory and excellent in workability at the construction site. .
[0077]
In addition, when an upper pressing member is provided on the rod-shaped connecting member to restrict the vertical movement of the connecting member and the lifting force of the column is transmitted to the rod-shaped connecting member, Since the vertical movement of the connecting member fixed to the base plate fixed to the leg portion is restricted, the leg portion of the column and the foundation structure can be reliably connected. Further, since the lifting force of the column is transmitted to the rod-like connecting member, it is possible to resist the drawing load.
[0078]
In addition, when the foundation structure consists of a pile foundation and a rod-shaped connecting member is provided directly on the pile foundation, the bending moment borne by the pile foundation can be reduced because the column base can be rotated and deformed. Therefore, a small-diameter pile foundation can be adopted, and the foundation structure can be simplified to reduce labor, construction period, or construction cost for foundation work.
[Brief description of the drawings]
FIG. 1 is an explanatory cross-sectional view showing a column base connecting structure according to the present invention.
FIG. 2 is an exploded perspective view showing how the lower support member and the foundation structure are assembled.
FIG. 3 is an exploded perspective view showing how a connecting member is assembled.
FIG. 4 is an exploded perspective view showing a state of assembling the column base and the connection member.
FIG. 5 is a perspective view showing a state in which a grout material is filled when a rod-like connecting member is embedded in a hollow steel pipe pile.
FIG. 6 is a cross-sectional explanatory view showing a configuration of a lower support member and a level cap.
FIG. 7 is an explanatory cross-sectional view showing a state in which the horizontal level of the lower support member and the vertical level of the rod-like connecting member are adjusted by the level cap when the steel pipe pile is installed obliquely.
FIG. 8 is an explanatory cross-sectional view showing a state in which the connection member is temporarily fixed when the column base is placed and fixed on the connection member.
FIG. 9 is an explanatory cross-sectional view illustrating a state in which a connecting member to which a column base is fixed is rotated and deformed by a shake such as an earthquake.
FIG. 10 is a perspective view showing a state in which a grout material is filled from a level cap having another configuration.
11 is an explanatory cross-sectional view showing an example of a lower support member used in the level cap of FIG.
FIG. 12 is a cross-sectional explanatory view showing the configuration of various lower support members.
FIG. 13 is an explanatory cross-sectional view showing configurations of various rod-like connecting members and a lower support member.
FIG. 14 is an exploded perspective view showing a state of assembling the lower support member and the foundation structure when three anchor bolts are used as rod-like connecting members.
FIG. 15 is an exploded perspective view showing a state where the connecting member is assembled and the column base and the connecting member are assembled when three anchor bolts are used as rod-like connecting members.
FIG. 16 is an explanatory cross-sectional view showing configurations of various foundation structures to which the column base connection structure according to the present invention can be applied.
FIG. 17 is an explanatory cross-sectional view showing configurations of various foundation structures to which the column base connection structure according to the present invention can be applied.
FIG. 18 is an explanatory cross-sectional view showing another configuration for adjusting the positions of columns and rod-like connecting members.
FIG. 19 is a cross-sectional explanatory view showing a configuration of another foundation structure to which the column base connection structure according to the present invention can be applied.
[Explanation of symbols]
1 ... Pillar
2 ... Steel pipe pile
3 ... Rod-shaped connecting member
4 ... Filler
5 ... Damping member
6 ... Ground
7 Level cap
7a ... hole
7b ... Top end face
7c, 7d ... filling port
7e ... Inking
8 ... Holding bolt
9 ... Lower support member
9a ... hole
9b ... convex portion
9c ... Positioning mark
9d ... Filling port
10… Connecting member
10a ... hole
11… Base plate
11a ... hole
11b ... Position adjustment area
12 ... Fixing plate
13… Upper holding member
13a ... hole
14 ... Nut
15a, 15b ... funnel
16a, 16b ... set camber
17… Ring-shaped member
18 ... Plate
19 ... Bolt
20 ... PC pile
21 ... Ground improvement body
22 ... Steel pipe
23 ... SC pile
24 ... PHC pile
25 ... RC basics
26 ... Reinforcing bars
27 ... Fixing auxiliary plate
27a ... Filling port
28… Fabric foundation
29 ... Written stone
30 ... concrete

Claims

A rod-shaped connecting member provided on the foundation structure is projected from the head of the foundation structure at a position substantially at the center of the cross section of the column connected to the foundation structure, and is convex on the head of the foundation structure the rod-like connecting the lower support member to the plate-like connecting member for fixing the lower the convex portion of the support member Rutotomoni provided in a state of inserting the rod-like connecting member, a base plate which is fixed to the leg portion of the column having a section with inserting the member, that the connecting member and location mounting a rotary deformable state on the convex portion of the lower support member, and fixing the base plate which is fixed to the leg portion of the connecting member and the pillar A column base connecting structure characterized in that the column leg and the base structure are connected with each other.

The upper pressing member is provided on the rod-like connecting member, the vertical movement of the connecting member is restricted, and the lifting force of the column is transmitted to the rod-like connecting member. Column base connection structure.

The column base connection structure according to claim 1, wherein the foundation structure is a pile foundation, and the rod-like connection member is provided directly on the pile foundation.