JP2006083623A - Foundation structure of exposed column base - Google Patents

Foundation structure of exposed column base Download PDF

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JP2006083623A
JP2006083623A JP2004270497A JP2004270497A JP2006083623A JP 2006083623 A JP2006083623 A JP 2006083623A JP 2004270497 A JP2004270497 A JP 2004270497A JP 2004270497 A JP2004270497 A JP 2004270497A JP 2006083623 A JP2006083623 A JP 2006083623A
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rising
muscle
foundation
foundation structure
column base
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JP4570139B2 (en
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Harukatsu Kadoya
治克 角屋
Shunji Fujii
俊二 藤井
Naoki Hirashima
直樹 平島
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Okabe Co Ltd
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Okabe Co Ltd
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Abstract

<P>PROBLEM TO BE SOLVED: To improve workability of reinforcement arranging work by reducing the arranged quantity of rising reinforcements arranged around anchor bolts in the foundation structure of an exposed column base, to relieve the competing state with the reinforcement arrangement of beam main reinforcements or the like for a foundation beam. <P>SOLUTION: In the foundation structure of the exposed column base for anchoring a column to foundation concrete 3 through a plurality of anchor bolts 6 provided with anchor plates 5, the rising reinforcements for reinforcing drag on the foundation concrete 3 side to tensile force applied to the anchor bolts 6 are arranged divided into first rising reinforcements 7 arranged at least at four corners around the anchor bolts 6, and second rising reinforcements 8 arranged at the center part of the foundation structure. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

本発明は、鉄骨造や充填鋼管コンクリート造などに適用される露出型柱脚の基礎構造に関する。   The present invention relates to a foundation structure of an exposed-type column base applied to a steel frame structure, a filled steel pipe concrete structure, or the like.

露出型柱脚の基礎構造は、アンカーボルトと立上り筋（柱主筋）とその立上がり筋に沿って支持されるフープ筋によって構成される（特許文献１、特許文献２参照）。そして、アンカーボルトの下端部に備えた定着板を介して定着する方式を採用した場合には、立上り筋は、アンカーボルトに作用する引張力により定着板を中心に上方に４５度の円錐面状に生起する基礎コンクリートのコーン状破壊を防いだり、そのコーン状破壊後にアンカーボルトに作用する引抜き力によって破壊面から離脱して崩壊するのを防ぐ機能を担うことになる。一般的には、柱脚部に曲げモーメントが作用した場合を想定し、引張側のアンカーボルトに作用する引張力に耐え得る本数（強度）の立上がり筋をその引張側アンカーボルトの周囲に配筋するという考え方の下に、柱脚部に作用する曲げモーメントの方向を変えながら全アンカーボルトの周囲に必要な立上がり筋の配筋量を求めて配筋がされている。その立上がり筋の配筋量は実際には相当多くなり、前記特許文献１，２では図面表現上から少ないが更に密に配筋され、立上がり筋相互間の間隔は狭いのが実状である。ところで、この露出型柱脚の基礎構造部分には、梁主筋等の基礎梁のための配筋も行われるため、前記立上がり筋と競合して配筋作業がきわめて煩雑になり、施工性を大きく低下させる原因になっていた。さらに、近年では高強度のアンカーボルトを使用した柱脚が数多く開発され、それに伴い１本当りのアンカーボルトの引張強度が大きくなり、基礎柱型内に配筋する立上り筋の配筋量も多くなる傾向にあることから、前記配筋上の競合問題が更に増長される傾向にある。
特許第２８７８８００号公報 特開平１−１６３３２１号公報 The basic structure of the exposed column base is composed of an anchor bolt, a rising muscle (column main muscle), and a hoop that is supported along the rising muscle (see Patent Document 1 and Patent Document 2). And when the method of fixing through the fixing plate provided at the lower end portion of the anchor bolt is adopted, the rising streaks have a conical surface shape of 45 degrees upward with the fixing plate as the center by the tensile force acting on the anchor bolt. It prevents the cone-like destruction of the foundation concrete that occurs in the surface, and prevents it from breaking away from the fracture surface by the pulling force acting on the anchor bolt after the cone-like destruction. In general, assuming that a bending moment is applied to the column base, the number of risers (strength) that can withstand the tensile force acting on the tension side anchor bolt are arranged around the tension side anchor bolt. Based on the idea of doing this, the arrangement is made by obtaining the amount of rising reinforcement necessary around all anchor bolts while changing the direction of the bending moment acting on the column base. Actually, the amount of arrangement of the rising streaks is considerably large, and in Patent Documents 1 and 2, although it is small in terms of drawing, it is more densely arranged, and the interval between the rising streaks is narrow. By the way, in the foundation structure part of this exposed type column base, reinforcement for the foundation beam such as the main beam of the beam is also performed, so that the arrangement work becomes extremely complicated by competing with the rising reinforcement, and the workability is greatly increased. It was a cause to lower. Furthermore, in recent years, many column bases using high-strength anchor bolts have been developed. As a result, the tensile strength of each anchor bolt has increased, and the amount of upright bars that have been placed in the foundation column has increased. Therefore, the competition problem on the bar arrangement tends to be further increased.
Japanese Patent No. 2878800 JP-A-1-163321

本発明は、以上のような従来の技術的状況に鑑みて開発したもので、露出型柱脚の基礎構造においてアンカーボルトの周囲に配筋される立上がり筋の配筋量を減らし、梁主筋等の基礎梁用の配筋との競合状態を緩和することにより、配筋作業の施工性を改善することを目的とする。   The present invention was developed in view of the above-described conventional technical situation, and reduces the amount of rising bars arranged around the anchor bolts in the foundation structure of the exposed column base, The purpose is to improve the workability of the bar arrangement work by alleviating the competition with the bar arrangement for the foundation beam.

前記課題を解決するために種々の実験研究を重ねた結果、前記立上がり筋の配筋位置として従来常識化していたアンカーボルトの周囲のフープ筋に沿った位置から基礎構造の中央部へ移行しても、立上がり筋として遜色のない作用効果が得られるだけでなく、柱脚部に作用する軸力や曲げに対しても有効であり、柱脚部としての性能を充分維持し得ることが判明した。図１はフープ筋に沿って立上がり筋を配筋した従来の配置例に関する説明図であり、正面図（イ）で示したように例えば柱脚部１０１に曲げモーメントＭａが作用した場合には、横断面図（ロ）で示したようにアンカーボルト１０２のうち、領域Ａの部分に位置するアンカーボルト１０２ａ，ｂに引張力が発生して前記曲げモーメントＭａに対抗することになる。そして、それらのアンカーボルト１０２ａ，ｂに作用した引張力によってそれらのアンカーボルトに設置した各定着板を中心に上方に４５度のコーン状破壊が発生するおそれが生じることになる。その際には、それらのコーン状破壊面を跨ぐ状態に配筋された各立上がり筋１０３に引張応力が発生して、コーン状破壊を未然に防止する機能を果したり、あるいはコーン状破壊後にアンカーボルト１０２に作用する引抜き力によって破壊面から離脱して崩壊するのを防ぐ機能を担うことになる。図２は本発明を適用した配置例の場合を示した横断面図である。図示のように、本配置例では、前記立上がり筋１０３のうち、フープ筋１０４の支持に必要な四隅の立上がり筋１０３ａ〜ｄを残して、他のものは基礎構造の中央部へ移行すると同時に、直径の若干太い異形鉄筋からなる立上がり筋１０３ｅ〜ｈを採用した場合を例示した。すなわち、全体の立上がり筋１０３を、アンカーボルト１０２を囲む少なくとも四隅に配筋した立上がり筋１０３ａ〜ｄからなる第１立上がり筋と、基礎構造の中央部に配筋した立上がり筋１０３ｅ〜ｈからなる第２立上がり筋とに分けて配筋するようにした点で特徴を有する。なお、図中１０５は基礎コンクリートである。   As a result of repeating various experimental studies to solve the above-mentioned problem, the position of the rising muscle has shifted from the position along the hoop muscle around the anchor bolt, which has been conventionally known as the arrangement position of the rising muscle, to the center of the foundation structure. However, it has been found that not only inferior effects can be obtained as rising streaks but also effective against axial force and bending acting on the column base, and the performance as the column base can be sufficiently maintained. . FIG. 1 is an explanatory diagram relating to a conventional arrangement example in which rising muscles are arranged along the hoop muscles. When a bending moment Ma acts on the column base 101 as shown in the front view (a), for example, As shown in the cross-sectional view (b), a tensile force is generated in the anchor bolts 102a and 102b located in the region A of the anchor bolt 102 to counter the bending moment Ma. Then, there is a risk that a 45 degree cone-like fracture may occur upwardly around the fixing plates installed on the anchor bolts due to the tensile force acting on the anchor bolts 102a and 102b. In that case, tensile stress is generated in each rising muscle 103 arranged in a state straddling the cone-shaped fracture surface, and the cone-shaped fracture can be prevented in advance, or after the cone-shaped fracture The pulling force acting on the anchor bolts 102 serves to prevent the breakage from breaking away from the fracture surface. FIG. 2 is a cross-sectional view showing an arrangement example to which the present invention is applied. As shown in the drawing, in the present arrangement example, among the rising muscles 103, the rising muscles 103a to 103d at the four corners necessary for supporting the hoop muscle 104 are left, and the other ones move to the central portion of the foundation structure. The case where the rising bars 103e to 103h made of deformed reinforcing bars having a slightly thick diameter are employed is illustrated. That is, the whole rising muscle 103 is composed of first rising muscles 103a to 103d that are arranged at least at four corners surrounding the anchor bolt 102, and first rising muscles 103e to 103h that are arranged at the center of the foundation structure. It has a feature in that it is divided into two rising streaks. In the figure, reference numeral 105 denotes foundation concrete.

図３〜図５は図２に示した本発明の配置例において他の方向の曲げモーメントＭｂ，Ｍｃ，Ｍｄが作用した場合の領域Ｂ，Ｃ，Ｄに関して示した横断面図である。図３に示したように、図２の曲げモーメントＭａとは逆の曲げモーメントＭｂが作用した場合には、領域Ｂ内のアンカーボルト１０２ｃ，ｄに引張力が作用し、第１立上がり筋としての周囲の立上がり筋１０３ｃ，ｄと第２立上がり筋としての中央部の立上がり筋１０３ｅ〜ｈが立上がり筋としての前記機能を奏することになる。同様に、曲げモーメントＭａ，Ｍｂに直交する方向の曲げモーメントＭｃが作用した場合には、図４に示したように領域Ｃ内のアンカーボルト１０２ａ，ｄに引張力が作用し、第１立上がり筋としての周囲の立上がり筋１０３ａ，ｄと第２立上がり筋としての中央部の立上がり筋１０３ｅ〜ｈが立上がり筋としての前記機能を奏することになる。また、曲げモーメントＭｄが作用した場合には、図５に示したように領域Ｄ内のアンカーボルト１０２ｂ，ｃに引張力が作用し、第１立上がり筋としての周囲の立上がり筋１０３ｂ，ｃと第２立上がり筋としての中央部の立上がり筋１０３ｅ〜ｈが立上がり筋としての前記機能を奏することになる。以上のように、曲げモーメントＭａ，Ｍｂ，Ｍｃ，Ｍｄに対して、第１立上がり筋としてのアンカーボルト１０２の周囲の立上がり筋１０３ａ〜ｄは機能する部分が変化するが、基礎構造の中央部の立上がり筋１０３ｅ〜ｈに関しては、いずれの方向の曲げモーメントＭａ，Ｍｂ，Ｍｃ，Ｍｄに対して常に全体が有効に機能することが判る。すなわち、以上のようにアンカーボルトの周囲の立上がり筋の一部を基礎構造の中央部へ移行しても、曲げモーメントが作用した場合における立上がり筋として遜色のない充分な補強機能を得ることができる。さらに、立上がり筋が基礎構造の中央部にも設置されることから、柱脚部に作用する軸力に対する抗力手段としても有効であるという利点をも得ることができる。そして、第１立上がり筋の総量が減少されることから、アンカーボルトの周囲に配筋する立上がり筋相互間の間隔が拡がり、基礎梁鉄筋等の配筋空間に余裕ができ、その配筋作業に関する施工性を向上し得ることが確認されている。   3 to 5 are cross-sectional views showing regions B, C, and D when bending moments Mb, Mc, and Md in other directions are applied in the arrangement example of the present invention shown in FIG. As shown in FIG. 3, when a bending moment Mb opposite to the bending moment Ma in FIG. 2 is applied, a tensile force is applied to the anchor bolts 102c, d in the region B, and the first rising streaks are The peripheral rising muscles 103c and 103d and the central rising muscles 103e to 103h as the second rising muscles perform the function as the rising muscles. Similarly, when a bending moment Mc in a direction perpendicular to the bending moments Ma and Mb acts, a tensile force acts on the anchor bolts 102a and 102d in the region C as shown in FIG. The surrounding rising muscles 103a and 103d and the second rising muscles 103e to 103h as the second rising muscle perform the function as the rising muscles. When the bending moment Md is applied, a tensile force is applied to the anchor bolts 102b, c in the region D as shown in FIG. 5, and the surrounding rising muscles 103b, c as the first rising muscles and the first The rising muscles 103e to 103h at the center as the two rising muscles perform the function as the rising muscle. As described above, with respect to the bending moments Ma, Mb, Mc, and Md, the functioning portions of the rising bars 103a to 103d around the anchor bolt 102 as the first rising bars change. It can be seen that the rising muscles 103e to 103h always function effectively with respect to the bending moments Ma, Mb, Mc and Md in any direction. That is, as described above, even if a part of the rising streaks around the anchor bolt is shifted to the center portion of the foundation structure, a sufficient reinforcing function that is inferior to the rising streaks when a bending moment is applied can be obtained. . Furthermore, since the rising muscle is also installed in the central portion of the foundation structure, it is possible to obtain an advantage that it is effective as a drag means against the axial force acting on the column base. Since the total amount of the first rising bars is reduced, the spacing between the rising bars that are arranged around the anchor bolts is widened, and there is room in the reinforcing bar space such as the foundation beam reinforcing bar. It has been confirmed that workability can be improved.

本発明では、以上の結果に基づいて、定着板を備えた複数本のアンカーボルトを介して柱を基礎コンクリートに立設する露出型柱脚の基礎構造において、前記アンカーボルトに作用する引張力に対する基礎コンクリート側の抗力を補強する立上がり筋を、全アンカーボルトを囲む少なくとも四隅に配筋する第１立上がり筋と、基礎構造の中央部に配筋する第２立上がり筋とに分けて配筋するという技術手段を採用した。なお、前記第２立上がり筋は、その上部をベースプレートより上方へ貫通させるようにしてもよいし、ベースプレートに固着するようにしてもよい。   In the present invention, based on the above results, in the foundation structure of the exposed column base in which the column is erected on the foundation concrete via a plurality of anchor bolts provided with fixing plates, the tensile force acting on the anchor bolt is applied. The riser reinforcement that reinforces the drag on the foundation concrete side is divided into a first riser reinforcement that is placed in at least four corners surrounding all anchor bolts and a second riser reinforcement that is placed in the center of the foundation structure. Adopted technical means. The second rising line may be penetrated upward from the base plate or may be fixed to the base plate.

本発明によれば、立上がり筋をアンカーボルトの周囲に配筋する第１立上がり筋と基礎構造の中央部に配筋する第２立上がり筋とに分け、一部の立上がり筋をスペース的に比較的ゆとりのある中央部へ移行することにより、アンカーボルトの周囲に配筋する立上がり筋の配筋量を減らしたので、基礎梁用の梁主筋等の他の配筋との競合が大きく緩和されることから、配筋作業の施工性を大幅に改善することができる。また、立上がり筋が基礎構造の中央部にも設置されることから、曲げモーメントに対する抗力機能に加えて、柱脚部に作用する軸力に対する抗力手段としても有効である。さらに、第２立上がり筋の上部をベースプレートより上方へ貫通させたり、ベースプレートに固着するようにすれば、柱に作用する軸力に対する抗力作用を更に効果的に得ることができる。   According to the present invention, the rising muscles are divided into the first rising muscles that are arranged around the anchor bolts and the second rising muscles that are arranged in the center of the foundation structure, and some of the rising muscles are relatively spatially separated. By moving to the center with a lot of space, the amount of the rising bars arranged around the anchor bolts has been reduced, which greatly reduces competition with other reinforcements such as the main beam for the foundation beam. Therefore, the workability of the bar arrangement work can be greatly improved. Further, since the rising muscle is also installed in the central portion of the foundation structure, it is effective as a drag means against the axial force acting on the column base in addition to the drag function against the bending moment. Furthermore, if the upper part of the second rising muscle is penetrated upward from the base plate or fixed to the base plate, a drag action against the axial force acting on the column can be obtained more effectively.

本発明においてアンカーボルトの周囲に配筋される第１立上がり筋の配筋状態に関しては、少なくともフープ筋の支持に必要な四隅に配筋するものであればよい。したがって、基礎構造の中央部に配筋する第２立上がり筋の配筋状態に関しては、上述の第１立上がり筋の配筋状態に関する条件を満たす限り、基礎梁主筋等の他の配筋状態などを勘案して自由な選定が可能であり、この第２立上がり筋の周囲にも例えばフープ筋やスパイラル筋を配筋してもよい。また、基礎構造の中央部に配筋される第２立上がり筋としては異形鉄筋等が使用され、アンカーボルトの下端部等に備えられる定着板を中心に４５度の円錐面状のコーン状破壊面を跨いだ状態に設置される。さらに、高強度の鉄筋を用いることで、第２立上がり筋の本数を減らしたり、径を小さくすることが可能であり、配筋作業に関する施工性を更に向上することが可能である。因みに、第２立上がり筋の上端部は、ベースプレートより下方の位置であってもよいが、前述のように、ベースプレートより上方へ貫通させたり、ベースプレートに固着するようにすれば、柱に作用する軸力が第２立上がり筋に的確に伝達されてより効果的な抗力作用が得られる。そして、後者の形態の場合には、アンカーボルトが少なくとも第２立上がり筋より先行して降伏するように設定すれば、アンカーボルトが降伏しても第２立上がり筋が引抜き力に対する抗力手段として機能し得ることから、柱脚部の耐震特性を向上できるとともに、建物の急激な崩壊を回避することができる。なお、第２立上がり筋の下端部は、定着板を設けたり、Ｌ字状などに折曲げてもよく、特に定着手段の有無や形式を問うものではない。また、アンカーボルトの設置本数に関しては、上述した四隅に１本ずつ設置する形態だけでなく、四隅に２本ずつ設置する形態や、四隅のアンカーボルト相互間に中間のアンカーボルトを設置する形態など、種々の形態に本発明を適用し得ることはいうまでもない。   In the present invention, regarding the bar arrangement state of the first rising bars arranged around the anchor bolts, it is sufficient that the bars are arranged at least at the four corners necessary for supporting the hoop. Accordingly, regarding the bar arrangement state of the second rising bar that is arranged in the center of the foundation structure, other bar arrangement states such as the main beam main bar bar, etc., as long as the condition regarding the bar arrangement state of the first rising bar described above is satisfied. In consideration of this, it is possible to select freely. For example, a hoop muscle or a spiral muscle may be arranged around the second rising muscle. In addition, a deformed reinforcing bar is used as the second rising bar arranged at the center of the foundation structure, and a conical fracture surface with a conical surface of 45 degrees around the fixing plate provided at the lower end of the anchor bolt, etc. It is installed in the state straddling. Furthermore, by using a high-strength reinforcing bar, it is possible to reduce the number of second rising bars or to reduce the diameter, and it is possible to further improve the workability regarding the bar arrangement work. Incidentally, the upper end portion of the second rising muscle may be at a position below the base plate, but as described above, if it penetrates upward from the base plate or is fixed to the base plate, the axis acting on the column The force is accurately transmitted to the second rising muscle, and a more effective drag action is obtained. In the latter case, if the anchor bolt is set to yield at least before the second rising bar, the second rising bar functions as a drag means against the pulling force even if the anchor bolt yields. Thus, the seismic characteristics of the column base can be improved and a sudden collapse of the building can be avoided. Note that the lower end portion of the second rising line may be provided with a fixing plate, or may be bent in an L shape or the like, and there is no particular limitation on the presence or form of fixing means. In addition, regarding the number of anchor bolts installed, not only the above-described configuration in which one is installed at each of the four corners, but also a configuration in which two are installed at each of the four corners, a configuration in which an intermediate anchor bolt is installed between the anchor bolts at the four corners, etc. Needless to say, the present invention can be applied to various forms.

図６は本発明の第１実施例を示した縦断面図である。図中１は本実施例に係る柱脚部で、この柱脚部１を介して柱材２が基礎コンクリート３に定着される。柱脚部１は、柱材２の下端部に溶接等により固着されたベースプレート４と、このベースプレート４に形成された各挿通孔に挿通した状態に設置され、下端部近傍に設けた定着板５を介して基礎コンクリート３に定着される複数本のアンカーボルト６と、それらのアンカーボルト６の周囲に配筋された第１立上がり筋７と中央部に配筋された第２立上がり筋８とからなる立上がり筋と、第１立上がり筋７の周囲に結着されたフープ筋９とから構成され、それらの基礎コンクリート３に埋設されたアンカーボルト６、第１立上がり筋７、第２立上がり筋８、及びフープ筋９によって柱脚部１の基礎構造を構成している。なお、この場合、実験によると、フープ筋９の有効本数、単位断面積、及び降伏耐力を乗じた値を、アンカーボルト６の有効本数、単位断面積、及び降伏耐力を乗じた値で除した値が０．４以上になるように設定すると、フープ筋９による基礎コンクリート３に対する十分な補強作用が得られ、立上がり筋７，８の機能を十分に活用できるのに対して、前記条件を満たさない場合には、立上がり筋７，８より先にフープ筋９が降伏してしまい、立上がり筋７，８の機能が十分得られずにアンカーボルト６が抜けてしまう事態が生起するおそれがあることが確認されている。この点は以下の実施例においても同様である。さらに、本実施例では、図示のように第２立上がり筋８の上部は、ベースプレート４に形成された中央開口部１０を貫通して柱材２の下方内部に挿入され、グラウト材等の硬化材１１により定着される。これにより、柱材２に作用する軸力は、第２立上がり筋８へ的確に伝達されることになる。因みに、本実施例において第２立上がり筋８よりアンカーボルト６が先行して降伏するように設定すれば、アンカーボルト６が降伏しても第２立上がり筋８が引抜き力に対する抗力手段として機能することから、柱脚部１の耐震性能を向上でき、建物の急激な崩壊を回避することができる。   FIG. 6 is a longitudinal sectional view showing a first embodiment of the present invention. In the figure, reference numeral 1 denotes a column base according to the present embodiment, and the column material 2 is fixed to the foundation concrete 3 through the column base 1. The column base 1 is installed in a state where it is inserted into each insertion hole formed in the base plate 4 fixed to the lower end of the column 2 by welding or the like, and a fixing plate 5 provided in the vicinity of the lower end. A plurality of anchor bolts 6 that are fixed to the foundation concrete 3 through the first, the first rising bars 7 that are arranged around the anchor bolts 6, and the second rising bars 8 that are arranged in the center. An anchor bolt 6 embedded in the foundation concrete 3, a first rising muscle 7, a second rising muscle 8, and a hoop muscle 9 bound around the first rising muscle 7. Further, the foundation structure of the column base 1 is constituted by the hoop muscles 9. In this case, according to an experiment, the value obtained by multiplying the effective number of hoop bars 9, the unit cross-sectional area, and the yield strength is divided by the value obtained by multiplying the effective number of anchor bolts 6, the unit cross-sectional area, and the yield strength. When the value is set to be 0.4 or more, a sufficient reinforcing action for the foundation concrete 3 by the hoop bars 9 can be obtained and the functions of the rising bars 7 and 8 can be fully utilized, while the above condition is satisfied. If not, the hoop muscle 9 yields before the rising muscles 7 and 8, and the function of the rising muscles 7 and 8 cannot be obtained sufficiently and the anchor bolt 6 may come off. Has been confirmed. This also applies to the following embodiments. Further, in the present embodiment, as shown in the drawing, the upper portion of the second rising muscle 8 passes through the central opening 10 formed in the base plate 4 and is inserted into the lower part of the pillar member 2 to harden the grout material or the like. 11 is fixed. As a result, the axial force acting on the column member 2 is accurately transmitted to the second rising muscle 8. Incidentally, in this embodiment, if the anchor bolt 6 is set to yield before the second rising bar 8, the second rising bar 8 functions as a drag means against the pulling force even if the anchor bolt 6 yields. Therefore, the seismic performance of the column base 1 can be improved, and a sudden collapse of the building can be avoided.

しかして、本実施例において、柱材２を介して軸力Ｆや曲げモーメントＭが柱脚部１に作用すると、その曲げモーメントＭの方向に応じてアンカーボルト６に引抜き力、すなわち引張力が作用し、図示のように下部に設けた定着板５を中心に上方へ略４５度のコーン状破壊面１２が仮想される。そして、そのコーン状破壊面１２を跨ぐ第１立上がり筋７と第２立上がり筋８の部分には、該コーン状破壊面１２を挟んだ上下方向の変位に応じて引張応力が生じ、その変位に対する抗力を発生することから、そのコーン状破壊を防止したり、破壊後のコーン状破壊面１２を挟んで上下に離間して崩壊するのを抑制する機能を奏することになる。ここで、特に重要なことは、このコーン破壊に対する立上がり筋の機能は、第１立上がり筋７と第２立上がり筋８とがトータルで機能することから、第１立上がり筋７の設置本数の設定に当っては、その点を考慮して第１立上がり筋７の本数を削減することであり、これにより従来常識化されていたフープ筋９に沿って配筋される多数の立上がり筋からなる狭い相互間隔を拡大して、基礎梁主筋等の配筋作業の施工性を大幅に改善することが可能となる。   Thus, in this embodiment, when the axial force F or the bending moment M acts on the column base 1 via the column member 2, the pulling force, that is, the tensile force is applied to the anchor bolt 6 according to the direction of the bending moment M. As shown in the figure, a cone-shaped fracture surface 12 of approximately 45 degrees is imagined upward about the fixing plate 5 provided at the lower portion. Tensile stress is generated in the first rising muscle 7 and the second rising muscle 8 that straddle the cone-shaped fracture surface 12 according to the vertical displacement across the cone-shaped fracture surface 12, and against the displacement. Since the drag force is generated, the function of preventing the cone-like destruction or the function of preventing the cone-like destruction surface 12 after the destruction from being separated from each other up and down is exhibited. Here, it is particularly important that the function of the rising muscle with respect to the cone destruction is that the first rising muscle 7 and the second rising muscle 8 function in total, so that the number of the first rising muscles 7 to be set is set. In consideration of this point, the number of the first rising muscles 7 is reduced, and as a result, a narrow mutual structure composed of a large number of rising muscles arranged along the hoop muscle 9 which has been conventionally known. By expanding the interval, it becomes possible to greatly improve the workability of the bar arrangement work such as the foundation beam main reinforcement.

図７〜図９は本発明の第２実施例を示したもので、図７は図８に指示したＡ−Ａ断面図、図８は平面図、図９は図８に指示したＢ−Ｂ断面図である。本実施例に係る柱脚部１３は、Ｈ形鋼からなる柱材１４の下端部に溶接等により固着されたベースプレート１５と、このベースプレート１５に形成された各挿通孔に挿通設置され、下端部近傍に設けた定着板１６を介して基礎コンクリート１７に定着された複数本のアンカーボルト１８と、それらのアンカーボルト１８の周囲に配筋された第１立上がり筋１９と中央部に配筋され上部がベースプレート１５に形成された挿通孔を介して固着された第２立上がり筋２０とからなる立上がり筋と、第１立上がり筋１９の周囲に結着されたフープ筋２１とから構成され、それらの基礎コンクリート１７に埋設されたアンカーボルト１８、第１立上がり筋１９、第２立上がり筋２０、及びフープ筋２１によって柱脚部１３の基礎構造を構成している。すなわち、この第２実施例は、柱脚部１３の基礎構造の中央部に配筋する第２立上がり筋２０の上部をベースプレート１５に形成された挿通孔に挿通して上方から締付ナット２２により締付け固定し、それらの第２立上がり筋２０とベースプレート１５とを一体的に固着することによって、柱材１４に作用する軸力を第２立上がり筋２０に伝達するように構成した点で特徴を有する。なお、図８に示したように、本実施例における第２立上がり筋２０はＨ形鋼からなる柱材１４のウエブ２３の両側に１本ずつ、アンカーボルト１８は両側のフランジ２４，２５の外側に３本ずつ設置している。そして、柱材１４を介して軸力Ｆや曲げモーメントＭが柱脚部１３に作用した場合には、図示のようにアンカーボルト１８の下部に設けた定着板１６を中心に上方へ略４５度のコーン状破壊面２６において、第１立上がり筋１９と第２立上がり筋２０とから構成される立上がり筋が前記第１実施例と同様の機能を奏することになる。因みに、本実施例では、柱材１４のウエブ２３を挟んで２本の第２立上がり筋２０を配筋したので、図９に示した水平方向の剪断力に対しても強化される。   7 to 9 show a second embodiment of the present invention. FIG. 7 is a cross-sectional view taken along the line A-A indicated in FIG. 8, FIG. 8 is a plan view, and FIG. 9 is a line BB indicated in FIG. It is sectional drawing. The column base portion 13 according to the present embodiment is inserted and installed in a base plate 15 fixed to the lower end portion of the column member 14 made of H-shaped steel by welding and the like, and each insertion hole formed in the base plate 15. A plurality of anchor bolts 18 fixed to the foundation concrete 17 through a fixing plate 16 provided in the vicinity, first rising bars 19 arranged around the anchor bolts 18 and an upper portion arranged at the center. Is composed of a rising muscle composed of a second rising muscle 20 fixed through an insertion hole formed in the base plate 15, and a hoop muscle 21 bound around the first rising muscle 19, and their foundation The anchor bolt 18 embedded in the concrete 17, the first rising bar 19, the second rising bar 20, and the hoop bar 21 constitute the foundation structure of the column base 13. That is, in the second embodiment, the upper part of the second rising bar 20 arranged in the central portion of the foundation structure of the column base 13 is inserted into the insertion hole formed in the base plate 15 and is tightened from above with the tightening nut 22. It is characterized in that it is configured to transmit the axial force acting on the column 14 to the second rising muscle 20 by fastening and fixing, and fixing the second rising muscle 20 and the base plate 15 integrally. . As shown in FIG. 8, the second rising bars 20 in this embodiment are provided one on each side of the web 23 of the column 14 made of H-shaped steel, and the anchor bolts 18 are outside the flanges 24 and 25 on both sides. Three are installed in each. When an axial force F or a bending moment M acts on the column base portion 13 via the column member 14, it is approximately 45 degrees upward about the fixing plate 16 provided below the anchor bolt 18 as shown in the figure. In the cone-shaped fracture surface 26, the rising muscle composed of the first rising muscle 19 and the second rising muscle 20 performs the same function as in the first embodiment. Incidentally, in this embodiment, since the two second rising bars 20 are arranged with the web 23 of the column member 14 interposed, the horizontal shearing force shown in FIG. 9 is also strengthened.

図１０は本発明の第３実施例を示した縦断面図である。図示のように、本実施例に係る柱脚部２７は、前記第１実施例の変形例であり、基本的に同様の構成部分には同じ符号を付して説明すると、基礎構造の中央部に配筋する第２立上がり筋として１本の第２立上がり筋２８を使用し、その上部に定着板２９を設けて基礎コンクリート３に対する抵抗力を確保するように構成した点で特徴を有する。その他の構成においては第１実施例の場合と基本的な違いはなく、同様の作用効果を奏する。第２立上がり筋２８の上部は、柱材２やベースプレート４に対する結合関係はなく、第１実施例や第２実施例のように柱材２に作用する軸力や剪断力を第２立上がり筋２８へ直接的に伝達する機能は存しないが、本発明の最も重要で基本的な立上がり筋としての作用効果は奏する。すなわち、柱脚部２７に対して曲げモーメントＭが作用し、その曲げモーメントＭの方向に応じてアンカーボルト６に引張力が作用して、図示のようにアンカーボルト６の下端部近傍に設けた定着板５を中心に上方へ略４５度のコーン状破壊面１２が想定されるのに対して、そのコーン状破壊面１２を跨ぐ第１立上がり筋７と第２立上がり筋２８の部分がコーン状破壊を防止したり、破壊後のコーン状破壊面１２からの崩壊を抑制する機能を奏することになる。そして、第１立上がり筋７と第２立上がり筋２８とがトータルで機能することは第１実施例と同様であるから、第１立上がり筋７の設置本数を削減することにより従来常識化されていたフープ筋９に沿って配筋される立上がり筋の相互間隔を拡大して基礎梁主筋等の配筋作業の施工性を大幅に改善することが可能である。さらに、本実施例のように第２立上がり筋２８の上部に定着板２９を配設すれば、その第２立上がり筋２８に作用する引張力の反力として主に定着板２９を中心に延びる円錐面３０より下方のコンクリートに対して作用する下方への押圧力によって、コーン状破壊面１２からの崩壊が更に抑制されるという機能を得ることができる。因みに、この定着板２９の設置は必須ではなく、また第２立上がり筋２８の設置本数を増やしたり、高強度の鉄筋を用いることも可能である。   FIG. 10 is a longitudinal sectional view showing a third embodiment of the present invention. As shown in the drawing, the column base portion 27 according to the present embodiment is a modification of the first embodiment. Basically, the same reference numerals are given to the same components, and the center portion of the foundation structure will be described. One of the second rising bars 28 is used as the second rising bar, and a fixing plate 29 is provided above the second rising bar 28 to secure the resistance to the foundation concrete 3. In other configurations, there is no fundamental difference from the case of the first embodiment, and the same operational effects are achieved. The upper part of the second rising bar 28 is not connected to the column member 2 or the base plate 4, and the axial force or shearing force acting on the column member 2 is applied to the second rising member 28 as in the first and second embodiments. Although there is no direct transmission function, the most important and basic function of the present invention as a rising muscle is exhibited. That is, a bending moment M acts on the column base 27, and a tensile force acts on the anchor bolt 6 in accordance with the direction of the bending moment M, and it is provided near the lower end of the anchor bolt 6 as shown in the figure. While a cone-shaped fracture surface 12 of approximately 45 degrees is assumed upward about the fixing plate 5, the first rising muscle 7 and the second rising muscle 28 that straddle the cone-shaped fracture surface 12 are cone-shaped. The function to prevent destruction or to suppress the collapse from the cone-shaped destruction surface 12 after destruction is exhibited. And since it is the same as that of the first embodiment that the first rising muscle 7 and the second rising muscle 28 function in total, it has been made common sense by reducing the number of the first rising muscles 7 installed. It is possible to greatly improve the workability of the bar arrangement work such as the main beam of the foundation beam by increasing the interval between the rising bars arranged along the hoop bars 9. Further, if the fixing plate 29 is disposed on the upper part of the second rising stripe 28 as in the present embodiment, a cone extending mainly around the fixing plate 29 as a reaction force of the tensile force acting on the second rising stripe 28. A function of further suppressing the collapse from the cone-shaped fracture surface 12 can be obtained by the downward pressing force acting on the concrete below the surface 30. Incidentally, the installation of the fixing plate 29 is not essential, and the number of the second rising bars 28 can be increased or a high-strength reinforcing bar can be used.

従来の立上がり筋の配置例に関する説明図である。It is explanatory drawing regarding the example of arrangement | positioning of the conventional riser. 本発明の立上がり筋の配置例に関する横断面図である。It is a cross-sectional view regarding the example of arrangement | positioning of the rising stripe of this invention. 同配置例において他の方向の曲げモーメントが作用した場合を示した横断面図である。It is the cross-sectional view which showed the case where the bending moment of another direction acted in the example of arrangement | positioning. 同じく他の方向の曲げモーメントが作用した場合を示した横断面図である。It is the cross-sectional view which showed the case where the bending moment of another direction similarly acted. 同じく他の方向の曲げモーメントが作用した場合を示した横断面図である。It is the cross-sectional view which showed the case where the bending moment of another direction similarly acted. 本発明の第１実施例を示した縦断面図である。It is the longitudinal cross-sectional view which showed 1st Example of this invention. 本発明の第２実施例を示したＡ−Ａ断面図である。It is AA sectional drawing which showed 2nd Example of this invention. 同実施例を示した平面図である。It is the top view which showed the same Example. 同実施例を示したＢ−Ｂ断面図である。It is BB sectional drawing which showed the same Example. 本発明の第３実施例を示した縦断面図である。It is the longitudinal cross-sectional view which showed 3rd Example of this invention.

符号の説明Explanation of symbols

１…柱脚部、２…柱材、３…基礎コンクリート、４…ベースプレート、５…定着板、６…アンカーボルト、７…第１立上がり筋、８…第２立上がり筋、９…フープ筋、１０…中央開口部、１１…硬化材、１２…コーン状破壊面、１３…柱脚部、１４…柱材、１５…ベースプレート、１６…定着板、１７…基礎コンクリート、１８…アンカーボルト、１９…第１立上がり筋、２０…第２立上がり筋、２１…フープ筋、２２…締付ナット、２３…ウエブ、２４，２５…フランジ、２６…コーン状破壊面、２７…柱脚部、２８…第２立上がり筋、２９…定着板、３０…円錐面


DESCRIPTION OF SYMBOLS 1 ... Column base part, 2 ... Column material, 3 ... Foundation concrete, 4 ... Base plate, 5 ... Fixing plate, 6 ... Anchor bolt, 7 ... 1st riser, 8 ... 2nd riser, 9 ... Hoop, 10 ... central opening, 11 ... hardened material, 12 ... cone-shaped fracture surface, 13 ... column base, 14 ... pillar material, 15 ... base plate, 16 ... fixing plate, 17 ... foundation concrete, 18 ... anchor bolt, 19 ... first 1 ... Rise, 20 ... 2nd rise, 21 ... Hoop, 22 ... Clamping nut, 23 ... Web, 24, 25 ... Flange, 26 ... Cone-shaped fracture surface, 27 ... Column base, 28 ... Second rise Streaks 29 ... Fixing plate 30 ... Conical surface


Claims (3)

定着板を備えた複数本のアンカーボルトを介して柱を基礎コンクリートに立設する露出型柱脚の基礎構造において、前記アンカーボルトに作用する引張力に対する基礎コンクリート側の抗力を補強する立上がり筋を、全アンカーボルトを囲む少なくとも四隅に配筋する第１立上がり筋と、基礎構造の中央部に配筋する第２立上がり筋とに分けて配筋したことを特徴とする露出型柱脚の基礎構造。   In the foundation structure of the exposed column base where the column is erected on the foundation concrete via a plurality of anchor bolts equipped with fixing plates, the riser reinforcement that reinforces the resistance on the foundation concrete side against the tensile force acting on the anchor bolt The foundation structure of the exposed type column base, wherein the reinforcement is divided into a first rising muscle that is arranged in at least four corners surrounding all anchor bolts and a second rising reinforcement that is arranged in the center of the foundation structure. . 前記第２立上がり筋の上部をベースプレートより上方へ貫通させた請求項１に記載の露出型柱脚の基礎構造。   The foundation structure of the exposed type column base according to claim 1, wherein an upper part of the second rising muscle is penetrated upward from the base plate. 前記第２立上がり筋の上部をベースプレートに固着した請求項１に記載の露出型柱脚の基礎構造。

The foundation structure of the exposed column base according to claim 1, wherein an upper part of the second rising muscle is fixed to a base plate.

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101131829B1 (en) * 2009-02-26 2012-03-30 엘아이지건설 주식회사 base plate and RCreinforce concrete construction method

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5931185B2 (en) 2014-03-17 2016-06-08 センクシア株式会社 Column structure and base member
JPWO2015140889A1 (en) 2014-03-17 2017-04-06 日立機材株式会社 Column structure and base member
WO2015140890A1 (en) 2014-03-17 2015-09-24 日立機材株式会社 Column structure and base member

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH04277224A (en) * 1991-03-01 1992-10-02 Sumitomo Metal Ind Ltd Exposed column base
JPH06193016A (en) * 1992-12-28 1994-07-12 Taisei Corp Build-in construction method of steel framed pillar leg part
JPH08170340A (en) * 1994-12-19 1996-07-02 Kingo Naito Pedestal structure and method of pedestal construction
JPH08253967A (en) * 1995-03-15 1996-10-01 Shimizu Corp Pedestal structure of steel framed steel pipe column
JPH11247294A (en) * 1998-03-04 1999-09-14 Shimizu Corp Structure of column leg part
JP2000297480A (en) * 1999-04-13 2000-10-24 Maeda Corp Reinforcing method for steel-pipe structure column base section
JP2003336266A (en) * 2002-05-21 2003-11-28 Hitachi Metals Ltd Exposed column base structure

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH04277224A (en) * 1991-03-01 1992-10-02 Sumitomo Metal Ind Ltd Exposed column base
JPH06193016A (en) * 1992-12-28 1994-07-12 Taisei Corp Build-in construction method of steel framed pillar leg part
JPH08170340A (en) * 1994-12-19 1996-07-02 Kingo Naito Pedestal structure and method of pedestal construction
JPH08253967A (en) * 1995-03-15 1996-10-01 Shimizu Corp Pedestal structure of steel framed steel pipe column
JPH11247294A (en) * 1998-03-04 1999-09-14 Shimizu Corp Structure of column leg part
JP2000297480A (en) * 1999-04-13 2000-10-24 Maeda Corp Reinforcing method for steel-pipe structure column base section
JP2003336266A (en) * 2002-05-21 2003-11-28 Hitachi Metals Ltd Exposed column base structure

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101131829B1 (en) * 2009-02-26 2012-03-30 엘아이지건설 주식회사 base plate and RCreinforce concrete construction method

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