JP2018003293A - Buckling stiffening structure and shape steel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a buckling stiffening structure and shape steel for restraining an expansion width of a plate element formed of a predetermined cross-sectional shape, and improving local buckling strength.SOLUTION: A buckling stiffening structure 1 of applying the present invention is provided in a plate element formed in a predetermined cross-sectional shape, and comprises an intermediate plate element 2 of continuing in the width direction X in a cross-sectional shape and a pair of side part plate elements 3 for extending by bending from both side parts 20 in the width direction X of the intermediate plate element 2. The pair of side part plate elements 3 are formed by mutually extending in the substantially same direction from both side parts 20 in the width direction X of the intermediate plate element 2, and the direction of extending the pair of side part plate elements 3 more than a virtual straight line S of connecting both side parts 20 in the width direction X of the intermediate plate element 2, becomes the inside direction α. The intermediate plate element 2 forms an inclined part 4 of inclining in the inside direction α by continuing from both side parts 20 in the width direction X, and a rib part 5 projecting toward the outside direction β of becoming the opposite side in the inside direction α from the inclined part 4, is formed in an intermediate part 21 in the width direction X.SELECTED DRAWING: Figure 6

Description

本発明は、所定の断面形状で形成された板要素に設けられる座屈補剛構造、及び、所定の断面形状で形成された板要素の座屈補剛構造が設けられる形鋼に関する。   The present invention relates to a buckling stiffening structure provided in a plate element formed with a predetermined cross-sectional shape, and a shaped steel provided with a buckling stiffening structure of a plate element formed with a predetermined cross-sectional shape.

従来から、構造が簡潔で製作工程も比較的容易であり、強度も著しく向上したスチールハウスの柱部材等に用いられる箱形断面形薄板部材として、特許文献１に開示される座屈補剛構造が提案されている。また、従来の溝形鋼又は内方補剛リブ付溝形鋼では得られない高い部材耐力を有するものとして、特許文献２に開示される溝形鋼が提案されている。   Conventionally, a buckling stiffening structure disclosed in Patent Document 1 as a box-shaped cross-section thin plate member used for a steel house column member or the like having a simple structure, a relatively easy manufacturing process, and significantly improved strength. Has been proposed. Moreover, the channel steel disclosed by patent document 2 is proposed as what has the high member yield strength which cannot be obtained with the conventional channel steel or channel steel with an internal stiffening rib.

特許文献１に開示される座屈補剛構造は、スチールハウス、住宅、工場建屋等の柱部材に用いられる箱形断面形薄板部材の座屈補剛構造であって、薄鋼板を箱形断面形状に曲げ形成して、箱形断面形状の各辺でコーナー部から中央部にかけて、無段階的又は段階的に箱形断面形状の中心部寄りに変位する複数の座屈補剛領域を形成したことを特徴とする。   The buckling stiffening structure disclosed in Patent Document 1 is a buckling stiffening structure of a box-shaped cross-section thin plate member used for a column member of a steel house, a house, a factory building, etc. Bending into a shape to form a plurality of buckling stiffening regions that are steplessly or gradually displaced toward the center of the box-shaped cross section from each corner of the box-shaped cross section to the center. It is characterized by that.

特許文献２に開示される溝形鋼は、該溝形鋼のウェブ部に、該ウェブ部の外側方向への最大張出し長さがフランジ部の幅の６０％以下となる張出し部を形成した断面形状となる。そして、特許文献２に開示される溝形鋼は、必要に応じて、張出し幅がウェブ部の幅の１０％以上となる張出し部を形成した断面形状を有することを特徴とする。   The cross-section steel disclosed in Patent Document 2 is a cross-section in which an overhang portion in which the maximum overhang length in the outer direction of the web portion is 60% or less of the width of the flange portion is formed in the web portion of the groove steel. It becomes a shape. The grooved steel disclosed in Patent Document 2 is characterized by having a cross-sectional shape in which an overhang portion having an overhang width of 10% or more of the width of the web portion is formed as necessary.

特開２００１−３２９６５６号公報JP 2001-329656 A 特開平９−２６８７０１号公報Japanese Patent Laid-Open No. 9-268701

ここで、特許文献１に開示される座屈補剛構造は、閉断面となる箱形断面形薄板部材に設けられて、無補剛の板要素に対して高い局部座屈強度が発揮される。しかし、特許文献１に開示される座屈補剛構造は、特許文献１の図２（Ａ）に示すように、箱形断面形状の各辺がコーナー部から中央部にかけて傾斜するものの、中央部が平坦な板要素で形成されているため、座屈補剛を施した板要素の中央部が局部的に回転する座屈モードが生じるという課題がある。   Here, the buckling stiffening structure disclosed in Patent Document 1 is provided in a box-shaped cross-sectional thin plate member having a closed cross section, and exhibits high local buckling strength with respect to a non-stiffening plate element. However, as shown in FIG. 2A of Patent Document 1, the buckling stiffening structure disclosed in Patent Document 1 is such that each side of the box-shaped cross-sectional shape is inclined from the corner portion to the center portion. Is formed of a flat plate element, there is a problem that a buckling mode occurs in which the central portion of the plate element subjected to buckling stiffening rotates locally.

また、特許文献１に開示される座屈補剛構造は、特許文献１の図７（Ｂ）に示すように、箱形断面形状の各辺がコーナー部から中央部にかけて傾斜するものでなく、また、箱形断面形状の中心部寄りに突出するリブ部のみが形成される場合に、各辺が奥行方向に移動する座屈モードが生じて局部座屈強度が低下する。   Further, the buckling stiffening structure disclosed in Patent Document 1 is not one in which each side of the box-shaped cross-sectional shape is inclined from the corner portion to the center portion as shown in FIG. Moreover, when only the rib part which protrudes near the center part of a box-shaped cross-sectional shape is formed, the buckling mode which each side moves to a depth direction arises, and local buckling strength falls.

さらに、特許文献２に開示される溝形鋼は、溝形鋼のウェブ部から突出する様々な形状の張出し部が形成されるものの、溝形鋼のウェブ部をその両側部から連続して内側方向に傾斜させたものではない。このため、特許文献２に開示される溝形鋼は、局部座屈強度を向上させるために、張出し部の最大張出し長さをある程度の大きさとする必要があるため、溝形鋼の展開幅や部材幅を抑制しながら局部座屈強度を向上させることが困難となる。   Furthermore, although the grooved steel disclosed in Patent Document 2 is formed with a protruding portion having various shapes protruding from the web portion of the grooved steel, the web portion of the grooved steel is continuously inward from both sides thereof. It is not inclined in the direction. For this reason, the grooved steel disclosed in Patent Document 2 needs to have a certain length of the maximum overhang length of the overhang portion in order to improve the local buckling strength. It becomes difficult to improve the local buckling strength while suppressing the member width.

そこで、本発明は、上述した問題点に鑑みて案出されたものであって、その目的とするところは、所定の断面形状で形成された板要素の展開幅を抑制しながら、局部座屈強度を向上させた座屈補剛構造及び形鋼を提供することにある。   Therefore, the present invention has been devised in view of the above-described problems, and its object is to locally buckle while suppressing the development width of a plate element having a predetermined cross-sectional shape. An object of the present invention is to provide a buckled stiffening structure and a shape steel with improved strength.

第１発明に係る座屈補剛構造は、所定の断面形状で形成された板要素に設けられる座屈補剛構造であって、断面形状で幅方向に連続する中間板要素と、前記中間板要素の幅方向の両側部から屈曲して延びる一対の側部板要素とを備え、一対の前記側部板要素は、前記中間板要素の幅方向の両側部から互いに略同一の方向に延びて形成されて、前記中間板要素の幅方向の両側部を結んだ仮想直線よりも一対の前記側部板要素が延びる方向が内側方向となって、前記中間板要素は、幅方向の両側部から連続して前記内側方向に傾斜する傾斜部が形成されるとともに、前記傾斜部から前記内側方向の反対側となる外側方向に向けて突出するリブ部が幅方向の中間部に形成されることを特徴とする。   A buckling stiffening structure according to a first aspect of the present invention is a buckling stiffening structure provided in a plate element having a predetermined cross-sectional shape, the intermediate plate element having a cross-sectional shape continuous in the width direction, and the intermediate plate A pair of side plate elements that bend and extend from both sides in the width direction of the element, and the pair of side plate elements extend in substantially the same direction from both sides in the width direction of the intermediate plate element. A direction in which the pair of side plate elements extend from an imaginary straight line formed by connecting both sides in the width direction of the intermediate plate element is an inner direction, and the intermediate plate element is formed from both sides in the width direction. An inclined portion that is continuously inclined in the inner direction is formed, and a rib portion that protrudes from the inclined portion toward the outer side that is opposite to the inner direction is formed in an intermediate portion in the width direction. Features.

第２発明に係る座屈補剛構造は、第１発明において、前記中間板要素及び一対の前記側部板要素は、前記中間板要素をウェブとするとともに前記側部板要素をフランジとする溝形鋼が用いられて、前記中間板要素の幅方向の両側部で、前記中間板要素と前記側部板要素とがなす屈曲角度θが９０°未満となることを特徴とする。   A buckling stiffening structure according to a second invention is the groove according to the first invention, wherein the intermediate plate element and the pair of side plate elements have a web as the intermediate plate element and a flange as the side plate element. Shape steel is used, and the bending angle θ formed by the intermediate plate element and the side plate element is less than 90 ° at both sides in the width direction of the intermediate plate element.

第３発明に係る座屈補剛構造は、第１発明又は第２発明において、前記中間板要素は、前記傾斜部から前記リブ部が最も突出する頂部までの前記リブ部の突出高ｈと、幅方向の両側部までの幅寸法ｂとが、下記（１）式により規定される関係を満足することを特徴とする。ここで、ｔ：前記中間板要素の板厚とする。   The buckling stiffening structure according to a third aspect of the present invention is the first aspect or the second aspect, wherein the intermediate plate element has a protrusion height h of the rib part from the inclined part to the top part where the rib part protrudes most, The width dimension b to both sides in the width direction satisfies the relationship defined by the following equation (1). Here, t is the thickness of the intermediate plate element.

第４発明に係る座屈補剛構造は、第１発明〜第３発明の何れかにおいて、前記中間板要素は、前記傾斜部から前記リブ部が最も突出する頂部が、前記仮想直線と略一致する位置に配置されることを特徴とする。   In the buckling stiffening structure according to a fourth aspect of the present invention, in any one of the first to third aspects, the intermediate plate element has a top portion from which the rib portion protrudes most from the inclined portion and substantially coincides with the virtual straight line. It arrange | positions in the position which carries out.

第５発明に係る形鋼は、所定の断面形状で形成された板要素の座屈補剛構造が設けられる形鋼であって、断面形状で幅方向に連続する中間板要素と、前記中間板要素の幅方向の両側部から屈曲して延びる一対の側部板要素とを備え、前記中間板要素及び一対の前記側部板要素は、前記中間板要素をウェブとするとともに前記側部板要素をフランジとする溝形鋼、前記中間板要素をフランジとするとともに前記側部板要素をウェブとするハット形鋼、又は、前記中間板要素をフランジとするとともに前記側部板要素をウェブ若しくはリップとするＺ形鋼が用いられて、一対の前記側部板要素は、前記中間板要素の幅方向の両側部から互いに略同一の方向に延びて形成されて、前記中間板要素の幅方向の両側部を結んだ仮想直線よりも一対の前記側部板要素が延びる方向が内側方向となって、前記中間板要素は、幅方向の両側部から連続して前記内側方向に傾斜する傾斜部が形成されるとともに、前記傾斜部から前記内側方向の反対側となる外側方向に向けて突出するリブ部が幅方向の中間部に形成されることを特徴とする。   A section steel according to a fifth aspect of the present invention is a section steel provided with a buckling stiffening structure for a plate element having a predetermined cross-sectional shape, the intermediate plate element having a cross-sectional shape continuous in the width direction, and the intermediate plate A pair of side plate elements that bend and extend from both sides in the width direction of the element, and the intermediate plate element and the pair of side plate elements use the intermediate plate element as a web and the side plate element Steel, a hat-shaped steel with the intermediate plate element as a flange and the side plate element as a web, or the intermediate plate element as a flange and the side plate element as a web or lip Z-shaped steel is used, and the pair of side plate elements are formed to extend in substantially the same direction from both sides in the width direction of the intermediate plate element, and are formed in the width direction of the intermediate plate element. A pair of the above-mentioned virtual straight lines connecting both sides The direction in which the part plate element extends is the inner direction, and the intermediate plate element is formed with an inclined part that inclines in the inner direction continuously from both sides in the width direction, and from the inclined part to the inner direction. The rib part which protrudes toward the outer side used as an other side is formed in the intermediate part of the width direction.

第１発明〜第４発明によれば、中間板要素の両側部から内側方向に傾斜する傾斜部が形成されるとともに、外側方向に向けて突出するリブ部が形成されることで、中間板要素の傾斜部及びリブ部を幅方向に展開させた展開幅を抑制しながら、局部座屈強度を向上させることが可能となる。   According to 1st invention-4th invention, while the inclined part which inclines inward from the both sides of an intermediate plate element is formed, and the rib part which protrudes toward an outer side is formed, intermediate plate element It is possible to improve the local buckling strength while suppressing the development width obtained by developing the inclined portion and the rib portion in the width direction.

特に、第２発明によれば、所定の断面形状となる溝形鋼において、中間板要素の展開幅を抑制するとともに、局部座屈強度を向上させることが可能となる。   In particular, according to the second invention, in the grooved steel having a predetermined cross-sectional shape, it is possible to suppress the development width of the intermediate plate element and improve the local buckling strength.

特に、第３発明によれば、中間板要素において、リブ部の頂点までの突出高と、幅方向の両側部までの幅寸法とが、上記（１）式により規定される関係を満足することで、局部座屈強度を確実に向上させることが可能となる。   In particular, according to the third invention, in the intermediate plate element, the protrusion height to the top of the rib portion and the width dimension to both side portions in the width direction satisfy the relationship defined by the above formula (1). Thus, the local buckling strength can be reliably improved.

特に、第４発明によれば、中間板要素において、傾斜部からリブ部が最も突出する頂部が、仮想直線と略一致する位置に配置されることで、局部座屈強度を効率的に向上させることが可能となる。   In particular, according to the fourth invention, in the intermediate plate element, the top portion where the rib portion protrudes most from the inclined portion is disposed at a position substantially coincident with the virtual straight line, thereby effectively improving the local buckling strength. It becomes possible.

特に、第５発明によれば、所定の断面形状となる溝形鋼、ハット形鋼又はＺ形鋼の何れにおいても、中間板要素の展開幅を抑制するとともに、局部座屈強度を向上させることが可能となる。   In particular, according to the fifth invention, in any of the groove-shaped steel, hat-shaped steel or Z-shaped steel having a predetermined cross-sectional shape, the expansion width of the intermediate plate element is suppressed and the local buckling strength is improved. Is possible.

本発明を適用した座屈補剛構造を示す斜視図である。It is a perspective view which shows the buckling stiffening structure to which this invention is applied. （ａ）は、本発明を適用した座屈補剛構造のリップが形成された溝形鋼を示す平面図であり、（ｂ）は、リップが形成されない溝形鋼を示す平面図である。(A) is a top view which shows the channel steel in which the lip of the buckling stiffening structure to which this invention was applied was formed, (b) is a top view which shows the channel steel in which a lip is not formed. （ａ）は、本発明を適用した座屈補剛構造で互いに略平行に形成される一対の側部板要素を示す平面図であり、（ｂ）は、互いに離間するように形成される一対の側部板要素を示す平面図である。(A) is a top view which shows a pair of side board element formed in the buckling stiffening structure to which this invention is applied substantially parallel to each other, (b) is a pair formed so that it may mutually space apart. It is a top view which shows this side plate element. （ａ）は、本発明を適用した座屈補剛構造で仮想直線よりも外側方向に頂部が配置されたリブ部を示す平面図であり、（ｂ）は、仮想直線よりも内側方向に頂部が配置されたリブ部を示す平面図である。(A) is a top view which shows the rib part by which the top part was arrange | positioned in the outward direction rather than the virtual straight line in the buckling stiffening structure to which the present invention is applied, and (b) is the top part in the inner direction from the virtual straight line. It is a top view which shows the rib part by which is arrange | positioned. （ａ）は、本発明を適用した座屈補剛構造で略矩形状に形成されたリブ部を示す平面図であり、（ｂ）は、略湾曲形状に形成されたリブ部を示す平面図である。(A) is a top view which shows the rib part formed in the substantially rectangular shape by the buckling stiffening structure to which this invention is applied, (b) is a top view which shows the rib part formed in the substantially curved shape. It is. 本発明を適用した形鋼で座屈補剛構造が設けられる溝形鋼を示す平面図である。It is a top view which shows the channel steel by which a buckling stiffening structure is provided with the shape steel to which this invention is applied. 本発明を適用した形鋼で座屈補剛構造が設けられるハット形鋼を示す平面図である。It is a top view which shows the hat-shaped steel in which a buckling stiffening structure is provided with the shape steel to which this invention is applied. 本発明を適用した形鋼で座屈補剛構造が設けられるＺ形鋼を示す平面図である。It is a top view which shows the Z-section steel in which a buckling stiffening structure is provided with the shape steel to which this invention is applied. （ａ）〜（ｄ）は、比較例１〜４の数値解析モデルを示す平面図であり、（ｅ）は、本発明例の数値解析モデルを示す平面図である。(A)-(d) is a top view which shows the numerical analysis model of Comparative Examples 1-4, (e) is a top view which shows the numerical analysis model of the example of this invention. 本発明例及び比較例１〜４の各々のモデルについて、単位断面積あたりの弾性局部座屈強度を示すグラフである。It is a graph which shows the elastic local buckling strength per unit cross-sectional area about each model of this invention example and Comparative Examples 1-4. 本発明を適用した座屈補剛構造で突出高ｈ／幅寸法ｂと本発明例のモデルでの局部座屈強度との関係を示すグラフである。It is a graph which shows the relationship between the protrusion height h / width dimension b and the local buckling strength in the model of the example of this invention in the buckling stiffening structure to which this invention is applied. （ａ）は、幅寸法ｂ／板厚ｔを変化させた場合の突出高ｈ／幅寸法ｂと本発明例のモデルでの局部座屈強度との関係を示すグラフであり、（ｂ）は、幅寸法ｂ／板厚ｔと突出高ｈ／幅寸法ｂとの関係を示すグラフである。(A) is a graph showing the relationship between the protrusion height h / width dimension b when the width dimension b / plate thickness t is changed and the local buckling strength in the model of the present invention example, (b). 4 is a graph showing the relationship between width dimension b / plate thickness t and protrusion height h / width dimension b. （ａ）は、本発明を適用した座屈補剛構造でリブ部の幅寸法を示す平面図であり、（ｂ）は、中間板要素に対するリブ部の幅寸法を変化させた場合の突出高ｈ／幅寸法ｂと本発明例のモデルでの局部座屈強度との関係を示すグラフである。(A) is a top view which shows the width dimension of a rib part with the buckling stiffening structure to which this invention is applied, (b) is the protrusion height at the time of changing the width dimension of the rib part with respect to an intermediate | middle board element. It is a graph which shows the relationship between h / width dimension b and the local buckling strength in the model of the example of this invention. （ａ）は、本発明を適用した座屈補剛構造でリブ部の突出高を示す平面図であり、（ｂ）は、リブ部の突出高を変化させた場合のリブ部の突出高と本発明例のモデルでの局部座屈強度との関係を示すグラフである。(A) is a top view which shows the protrusion height of a rib part by the buckling stiffening structure to which this invention is applied, (b) is the protrusion height of the rib part at the time of changing the protrusion height of a rib part, and It is a graph which shows the relationship with the local buckling strength in the model of the example of this invention. 本発明を適用した座屈補剛構造でリブ部が略三角形状、略矩形状又は略円弧状に形成される場合の本発明例のモデルでの局部座屈強度を示すグラフである。It is a graph which shows the local buckling strength in the model of the example of this invention in case a rib part is formed in a substantially triangular shape, a substantially rectangular shape, or a substantially circular arc shape by the buckling stiffening structure to which this invention is applied.

以下、本発明を適用した座屈補剛構造１及び形鋼７を実施するための形態について、図面を参照しながら詳細に説明する。なお、図１〜図８では、本発明の内容を理解し易くするため、各々の板要素の板厚を大きくして表示している。   Hereinafter, the form for implementing the buckling stiffening structure 1 and the shape steel 7 to which this invention is applied is demonstrated in detail, referring drawings. In FIG. 1 to FIG. 8, the plate thickness of each plate element is shown enlarged to facilitate understanding of the contents of the present invention.

本発明を適用した座屈補剛構造１は、図１に示すように、主に、溝形鋼７１等の形鋼７に設けられる。本発明を適用した座屈補剛構造１は、形鋼７等の材軸方向Ｚに対して所定の断面形状で形成された板要素に設けられるものとなる。   As shown in FIG. 1, the buckling stiffening structure 1 to which the present invention is applied is mainly provided on a shape steel 7 such as a grooved steel 71. The buckling stiffening structure 1 to which the present invention is applied is provided on a plate element having a predetermined cross-sectional shape with respect to the material axis direction Z of the shape steel 7 or the like.

本発明を適用した座屈補剛構造１は、図２に示すように、材軸方向Ｚに対する断面形状で、幅方向Ｘに連続する中間板要素２と、中間板要素２の幅方向Ｘの両側部２０から屈曲して延びる一対の側部板要素３とを備える。本発明を適用した座屈補剛構造１は、溝形鋼７１に設けられる場合に、板要素の断面形状が略溝形状に形成される。   As shown in FIG. 2, the buckling stiffening structure 1 to which the present invention is applied has a cross-sectional shape with respect to the material axis direction Z, an intermediate plate element 2 continuous in the width direction X, and the width direction X of the intermediate plate element 2. And a pair of side plate elements 3 that are bent and extended from both side portions 20. In the buckling stiffening structure 1 to which the present invention is applied, when the grooved steel 71 is provided, the cross-sectional shape of the plate element is formed in a substantially groove shape.

本発明を適用した座屈補剛構造１は、溝形鋼７１に設けられる場合に、中間板要素２をウェブ７ａとするとともに側部板要素３をフランジ７ｂとする。このとき、本発明を適用した座屈補剛構造１は、図２（ａ）に示すように、フランジ７ｂの先端部にリップ７ｃが形成されるほか、図２（ｂ）に示すように、リップ７ｃが形成されなくてもよい。リップ７ｃが形成される場合は、鋼板等の折曲加工等により屈曲して形成されるため、フランジ７ｂとリップ７ｃとの境い目となる屈曲部分が多少湾曲した状態で形成されてもよい。   In the buckling stiffening structure 1 to which the present invention is applied, when the grooved steel 71 is provided, the intermediate plate element 2 is the web 7a and the side plate element 3 is the flange 7b. At this time, the buckling stiffening structure 1 to which the present invention is applied has a lip 7c formed at the tip of the flange 7b as shown in FIG. 2 (a), as shown in FIG. 2 (b). The lip 7c may not be formed. When the lip 7c is formed, the lip 7c is bent and formed by bending a steel plate or the like. Therefore, the bent portion that serves as a boundary between the flange 7b and the lip 7c may be slightly curved.

一対の側部板要素３は、図３に示すように、中間板要素２の幅方向Ｘの両側部２０から互いに略同一の方向に延びて形成される。このとき、一対の側部板要素３は、中間板要素２を境界として奥行方向Ｙの手前側又は奥側の何れかにのみ延びることで、中間板要素２の両側部２０から互いに略同一の方向に延びて形成されるものとなる。   As shown in FIG. 3, the pair of side plate elements 3 are formed to extend from both side portions 20 in the width direction X of the intermediate plate element 2 in substantially the same direction. At this time, the pair of side plate elements 3 are substantially identical to each other from both side portions 20 of the intermediate plate element 2 by extending only to the near side or the deep side in the depth direction Y with the intermediate plate element 2 as a boundary. It will be formed extending in the direction.

一対の側部板要素３は、奥行方向Ｙの手前側で、中間板要素２の幅方向Ｘの両側部２０を直線状に結んだ仮想直線Ｓよりも、一対の側部板要素３が延びる方向が内側方向αとなる。また、一対の側部板要素３は、奥行方向Ｙの奥側で、一対の側部板要素３が延びる内側方向αの反対側が外側方向βとなる。なお、一対の側部板要素３は、図示の中間板要素２及び側部板要素３を奥行方向Ｙに反転させた場合に、奥行方向Ｙの奥側が内側方向αとなって、奥行方向Ｙの手前側が外側方向βとなる。   The pair of side plate elements 3 extend in front of the depth direction Y, and the pair of side plate elements 3 extend from an imaginary straight line S that linearly connects both side portions 20 of the intermediate plate element 2 in the width direction X. The direction is the inner direction α. In addition, the pair of side plate elements 3 is on the back side in the depth direction Y, and the opposite side to the inner direction α in which the pair of side plate elements 3 extends is the outer direction β. When the illustrated intermediate plate element 2 and side plate element 3 are reversed in the depth direction Y, the depth side in the depth direction Y becomes the inner direction α, and the pair of side plate elements 3 becomes the depth direction Y. The near side is the outward direction β.

一対の側部板要素３は、図３（ａ）に示すように、中間板要素２の両側部２０から奥行方向Ｙで同一の方向に延びて、互いに略平行に形成される。また、一対の側部板要素３は、必要に応じて、図３（ｂ）に示すように、中間板要素２の両側部２０から奥行方向Ｙで略同一の方向に延びて、互いに幅方向Ｘで離間又は接近するように形成されてもよい。   As shown in FIG. 3A, the pair of side plate elements 3 extend from both side portions 20 of the intermediate plate element 2 in the same direction in the depth direction Y, and are formed substantially parallel to each other. Moreover, as shown in FIG. 3B, the pair of side plate elements 3 extend from both side portions 20 of the intermediate plate element 2 in substantially the same direction in the depth direction Y as shown in FIG. It may be formed so as to be separated or approached by X.

中間板要素２は、幅方向Ｘの両側部２０から連続して、奥行方向Ｙで内側方向αに傾斜する傾斜部４が形成される。また、中間板要素２は、内側方向αの反対側となる外側方向βに向けて突出するリブ部５が幅方向Ｘの中間部２１の一部に形成される。   The intermediate plate element 2 is formed with an inclined portion 4 that is continuous from both side portions 20 in the width direction X and is inclined in the depth direction Y in the inner direction α. Further, the intermediate plate element 2 is formed with a rib portion 5 protruding in the outer direction β opposite to the inner direction α in a part of the intermediate portion 21 in the width direction X.

中間板要素２は、幅方向Ｘの略中央となる位置、及び、幅方向Ｘの中央よりも右側又は左側となる位置が、幅方向Ｘの中間部２１となる。中間板要素２は、幅方向Ｘでリブ部５の両側方に傾斜部４が形成されて、主に、幅方向Ｘの略中央にリブ部５が配置されるほか、幅方向Ｘの中央よりも右側又は左側となる位置にリブ部５が配置されてもよい。   In the intermediate plate element 2, a position that is substantially the center in the width direction X and a position that is on the right side or the left side of the center in the width direction X is the intermediate portion 21 in the width direction X. The intermediate plate element 2 is formed with inclined portions 4 on both sides of the rib portion 5 in the width direction X, and the rib portion 5 is mainly disposed at the approximate center in the width direction X, as well as from the center in the width direction X. Also, the rib portion 5 may be arranged at a position on the right side or the left side.

傾斜部４は、中間板要素２の両側部２０から中間部２１まで連続して、略直線状に傾斜して形成されるほか、略湾曲状に傾斜して形成されてもよい。傾斜部４は、最も内側方向αとなる位置から、外側方向βに向けて屈曲させてリブ部５が形成される。また、傾斜部４は、最も内側方向αとなる位置よりも右側又は左側にリブ部５が形成されてもよい。   The inclined portion 4 is formed continuously from the both side portions 20 to the intermediate portion 21 of the intermediate plate element 2 so as to be inclined in a substantially linear shape, or may be formed in a substantially curved shape. The inclined portion 4 is bent from the position in the innermost direction α toward the outer direction β to form the rib portion 5. Further, the inclined portion 4 may be formed with the rib portion 5 on the right side or the left side of the position in the innermost direction α.

リブ部５は、傾斜部４から外側方向βに向けて屈曲させた部分が底部５１となるとともに、傾斜部４から外側方向βに向けて最も突出する部分が頂部５０となって、略三角形状等に形成される。リブ部５は、底部５１から頂部５０まで略直線状に傾斜して形成されるほか、底部５１から頂部５０まで略湾曲状に傾斜して形成されてもよい。   The rib portion 5 has a substantially triangular shape in which a portion bent from the inclined portion 4 toward the outer direction β becomes a bottom portion 51, and a portion that protrudes most from the inclined portion 4 toward the outer direction β becomes a top portion 50. Etc. are formed. The rib portion 5 may be formed to be inclined in a substantially linear shape from the bottom portion 51 to the top portion 50 or may be formed to be inclined in a substantially curved shape from the bottom portion 51 to the top portion 50.

中間板要素２の中間部２１の一部では、鋼板等の折曲加工等によりリブ部５が屈曲して形成されるため、リブ部５の底部５１又は頂部５０となる屈曲部分が多少湾曲した状態で形成されてもよい。   Since a part of the intermediate part 21 of the intermediate plate element 2 is formed by bending the rib part 5 by bending a steel plate or the like, the bent part that becomes the bottom part 51 or the top part 50 of the rib part 5 is slightly curved. It may be formed in a state.

リブ部５は、外側方向βに向けて最も突出する頂部５０が、奥行方向Ｙで仮想直線Ｓと略一致する位置に配置される。また、リブ部５は、図４（ａ）に示すように、奥行方向Ｙで仮想直線Ｓよりも外側方向βに頂部５０が配置されてもよい。さらに、リブ部５は、図４（ｂ）に示すように、傾斜部４から屈曲させた底部５１よりも外側方向βに向けて突出するものの、奥行方向Ｙで仮想直線Ｓよりも内側方向αに頂部５０が配置されてもよい。   The rib portion 5 is arranged at a position where the top portion 50 that protrudes most in the outer direction β substantially coincides with the virtual straight line S in the depth direction Y. Moreover, as shown in FIG. 4A, the rib portion 5 may have a top portion 50 arranged in the depth direction Y in the outer side direction β with respect to the virtual straight line S. Further, as shown in FIG. 4B, the rib portion 5 protrudes toward the outer side direction β from the bottom portion 51 bent from the inclined portion 4, but the inner side direction α from the virtual straight line S in the depth direction Y. The top 50 may be disposed at the top.

リブ部５は、主に、頂部５０を頂点とする略三角形状に形成される。また、リブ部５は、図５（ａ）に示すように、底部５１から頂部５０まで略直線状とするとともに頂部５０を略直線状とした略矩形状に形成されてもよく、図５（ｂ）に示すように、底部５１から頂部５０まで略円弧状等に湾曲させた略湾曲形状に形成されてもよい。   The rib portion 5 is mainly formed in a substantially triangular shape having the top portion 50 as a vertex. Further, as shown in FIG. 5A, the rib portion 5 may be formed in a substantially rectangular shape having a substantially straight shape from the bottom portion 51 to the top portion 50 and the top portion 50 being substantially straight. As shown to b), you may form in the substantially curved shape curved in the substantially circular arc shape etc. from the bottom part 51 to the top part 50. FIG.

中間板要素２及び一対の側部板要素３は、例えば、図６に示すように、中間板要素２をウェブ７ａとするとともに側部板要素３をフランジ７ｂとする溝形鋼７１が用いられる。このとき、中間板要素２及び一対の側部板要素３は、一対の側部板要素３が互いに略平行に形成されるとともに、中間板要素２の両側部２０から連続して傾斜部４が内側方向αに傾斜することで、中間板要素２と側部板要素３とがなす屈曲角度θが９０°未満となる。   For example, as shown in FIG. 6, the intermediate plate element 2 and the pair of side plate elements 3 are formed of a groove steel 71 having the intermediate plate element 2 as a web 7 a and the side plate element 3 as a flange 7 b. . At this time, the intermediate plate element 2 and the pair of side plate elements 3 are formed so that the pair of side plate elements 3 are substantially parallel to each other and the inclined portions 4 are continuously formed from both side portions 20 of the intermediate plate element 2. By inclining in the inward direction α, the bending angle θ formed by the intermediate plate element 2 and the side plate element 3 becomes less than 90 °.

なお、中間板要素２及び一対の側部板要素３は、一対の側部板要素３が互いに幅方向Ｘで離間又は接近するように形成される場合であっても、中間板要素２と側部板要素３とがなす屈曲角度θを９０°未満とすることができる。そして、中間板要素２の両側部２０では、鋼板等の折曲加工等により側部板要素３が屈曲して形成されるため、中間板要素２と側部板要素３との境い目となる屈曲部分が多少湾曲した状態で形成されてもよい。   Even if the intermediate plate element 2 and the pair of side plate elements 3 are formed so that the pair of side plate elements 3 are separated or approach each other in the width direction X, the intermediate plate element 2 and the side plate elements 3 The bending angle θ formed by the part plate element 3 can be less than 90 °. Since the side plate element 3 is bent at the both side portions 20 of the intermediate plate element 2 by bending a steel plate or the like, the bend serving as a boundary between the intermediate plate element 2 and the side plate element 3 is formed. The portion may be formed in a slightly curved state.

本発明を適用した形鋼７は、図６〜図８に示すように、幅方向Ｘに連続する中間板要素２と、中間板要素２の幅方向Ｘの両側部２０から屈曲して延びる一対の側部板要素３とを備える。そして、本発明を適用した形鋼７は、所定の断面形状で形成された溝形鋼７１、ハット形鋼７２又はＺ形鋼７３に、本発明を適用した座屈補剛構造１が設けられる。   As shown in FIGS. 6 to 8, the shape steel 7 to which the present invention is applied is a pair of bent and extended from the intermediate plate element 2 continuous in the width direction X and the both side portions 20 of the intermediate plate element 2 in the width direction X. Side plate element 3. In the structural steel 7 to which the present invention is applied, the buckling stiffening structure 1 to which the present invention is applied is provided on the groove-shaped steel 71, the hat-shaped steel 72, or the Z-shaped steel 73 formed with a predetermined cross-sectional shape. .

本発明を適用した形鋼７は、主に、図６に示すように、溝形鋼７１に本発明を適用した座屈補剛構造１が設けられる。このとき、本発明を適用した形鋼７は、中間板要素２及び一対の側部板要素３として、中間板要素２をウェブ７ａとするとともに一対の側部板要素３の各々をフランジ７ｂとする溝形鋼７１が用いられる。   The section steel 7 to which the present invention is applied is mainly provided with a buckling stiffening structure 1 to which the present invention is applied to a grooved steel 71 as shown in FIG. At this time, the shape steel 7 to which the present invention is applied includes the intermediate plate element 2 and the pair of side plate elements 3 as the web 7a and the pair of side plate elements 3 as flanges 7b. The grooved steel 71 is used.

また、本発明を適用した形鋼７は、必要に応じて、図７に示すように、幅方向Ｘに連続するフランジ７ｂ、フランジ７ｂから延びる一対のウェブ７ａ、及び、一対のウェブ７ａから延びる一対のアーム部７ｄを有するハット形鋼７２に座屈補剛構造１が設けられる。このとき、本発明を適用した形鋼７は、中間板要素２をフランジ７ｂとするとともに各々の側部板要素３を各々のウェブ７ａとするハット形鋼７２が用いられるものとなる。   Moreover, as shown in FIG. 7, the shape steel 7 to which the present invention is applied extends from a flange 7b continuous in the width direction X, a pair of webs 7a extending from the flange 7b, and a pair of webs 7a. The buckling stiffening structure 1 is provided on a hat-shaped steel 72 having a pair of arm portions 7d. At this time, the section steel 7 to which the present invention is applied uses the hat section steel 72 having the intermediate plate element 2 as the flange 7b and the side plate elements 3 as the respective webs 7a.

また、本発明を適用した形鋼７は、必要に応じて、図８に示すように、幅方向Ｘに連続する一対のフランジ７ｂ、一対のフランジ７ｂから延びるウェブ７ａ、及び、一対のフランジ７ｂから延びる一対のリップ７ｃを有するＺ形鋼７３に座屈補剛構造１が設けられる。このとき、本発明を適用した形鋼７は、一対の側部板要素３のうち一方がリップ７ｃとなるとともに他方がウェブ７ａとなり、中間板要素２をフランジ７ｂとするとともに側部板要素３をウェブ７ａ又はリップ７ｃとするＺ形鋼７３が用いられるものとなる。   In addition, as shown in FIG. 8, the shape steel 7 to which the present invention is applied includes a pair of flanges 7b continuous in the width direction X, a web 7a extending from the pair of flanges 7b, and a pair of flanges 7b. The buckling stiffening structure 1 is provided on a Z-shaped steel 73 having a pair of lips 7c extending from the same. At this time, in the structural steel 7 to which the present invention is applied, one of the pair of side plate elements 3 is a lip 7c and the other is a web 7a, and the intermediate plate element 2 is a flange 7b and the side plate element 3 is used. Z-shaped steel 73 having a web 7a or a lip 7c is used.

本発明を適用した座屈補剛構造１は、中間板要素２の両側部２０から内側方向αに傾斜する傾斜部４が形成されるとともに、外側方向βに向けて突出するリブ部５が形成されることで、形鋼７等における板要素の局部座屈強度を向上させるものとなる。ここで、局部座屈強度を向上させる効果を検証するために、図９に示すように、本発明を適用した座屈補剛構造１となる本発明例と、比較例１〜４とを比較して数値解析を実施した。   In the buckling stiffening structure 1 to which the present invention is applied, inclined portions 4 that are inclined in the inner direction α from both side portions 20 of the intermediate plate element 2 are formed, and rib portions 5 that protrude in the outer direction β are formed. By doing so, the local buckling strength of the plate element in the shape steel 7 or the like is improved. Here, in order to verify the effect of improving the local buckling strength, as shown in FIG. 9, the present invention example which becomes the buckling stiffening structure 1 to which the present invention is applied and the comparative examples 1 to 4 are compared. Then, numerical analysis was performed.

この数値解析では、本発明例及び比較例１〜４の何れにおいても、材軸方向Ｚの圧縮力を中間板要素２の全断面に均等に負荷して、中間板要素２の板厚ｔ及び両側部２０までの幅方向Ｘの幅寸法ｂを一定として、中間板要素２の両側部２０が支持されるモデルとした。図９（ａ）は、中間板要素２が内側方向αに傾斜せずリブ部５も形成されない比較例１のモデルを示す。また、図９（ｂ）は、中間板要素２が内側方向αに傾斜せず内側方向αに向けて突出するリブ部５が形成された比較例２のモデルを示す。また、図９（ｃ）は、中間板要素２が内側方向αに傾斜するもののリブ部５が形成されない比較例３のモデルを示す。さらに、図９（ｄ）は、中間板要素２が内側方向αに傾斜するものの内側方向αに向けて突出するリブ部５が形成された比較例４のモデルを示す。そして、図９（ｅ）は、中間板要素２が内側方向αに傾斜して外側方向βに向けて突出するリブ部５が形成された本発明例のモデルを示す。   In this numerical analysis, in any of the present invention example and Comparative Examples 1 to 4, the compression force in the material axis direction Z is evenly applied to the entire cross section of the intermediate plate element 2, and the thickness t and A model in which both side portions 20 of the intermediate plate element 2 are supported while the width dimension b in the width direction X to the both side portions 20 is constant. FIG. 9A shows a model of Comparative Example 1 in which the intermediate plate element 2 is not inclined in the inner direction α and the rib portion 5 is not formed. FIG. 9B shows a model of Comparative Example 2 in which the rib portion 5 is formed in which the intermediate plate element 2 is not inclined in the inner direction α but protrudes in the inner direction α. FIG. 9C shows a model of Comparative Example 3 in which the rib portion 5 is not formed although the intermediate plate element 2 is inclined in the inner direction α. Further, FIG. 9D shows a model of Comparative Example 4 in which the intermediate plate element 2 is inclined in the inner direction α, but the rib portion 5 protruding toward the inner direction α is formed. FIG. 9E shows a model of the present invention example in which the rib portion 5 in which the intermediate plate element 2 is inclined in the inner direction α and protrudes in the outer direction β is formed.

この数値解析の結果によると、破線で示すように、比較例１では、中間板要素２の全体が湾曲して幅方向Ｘの中央が奥行方向Ｙに移動する。また、比較例２、４では、幅方向Ｘの中央で中間板要素２が奥行方向Ｙに移動する。また、比較例３では、幅方向Ｘの中央で中間板要素２が回転する。これに対して、本発明例では、幅方向Ｘの中央で中間板要素２が奥行方向Ｙに移動せず、幅方向Ｘの中央で中間板要素２が回転もしないため、板要素に圧縮力が負荷された場合であっても、中間板要素２が座屈に対して高い抵抗を示すことがわかる。   According to the result of this numerical analysis, as shown by a broken line, in the comparative example 1, the entire intermediate plate element 2 is curved and the center in the width direction X moves in the depth direction Y. In Comparative Examples 2 and 4, the intermediate plate element 2 moves in the depth direction Y at the center in the width direction X. In Comparative Example 3, the intermediate plate element 2 rotates at the center in the width direction X. On the other hand, in the present invention example, the intermediate plate element 2 does not move in the depth direction Y in the center in the width direction X, and the intermediate plate element 2 does not rotate in the center in the width direction X. It can be seen that the intermediate plate element 2 exhibits a high resistance to buckling even when is loaded.

また、この数値解析の結果は、図１０に示すように、本発明例及び比較例１〜４の各々のモデルについて、単位断面積あたりの弾性局部座屈強度が示される。このとき、比較例１〜４では、幅方向Ｘの中央で中間板要素２が移動又は回転する座屈モードが生じるため、弾性局部座屈強度が小さくなる。これに対して、本発明例では、幅方向Ｘの中央で中間板要素２が移動も回転もしないため、弾性局部座屈強度が大きくなることから、本発明を適用した座屈補剛構造１での局部座屈強度を向上させる効果が検証された。   Moreover, as shown in FIG. 10, the result of this numerical analysis shows the elastic local buckling strength per unit cross-sectional area for each model of the present invention example and Comparative Examples 1 to 4. At this time, in Comparative Examples 1 to 4, since a buckling mode in which the intermediate plate element 2 moves or rotates in the center in the width direction X occurs, the elastic local buckling strength decreases. On the other hand, in the present invention example, since the intermediate plate element 2 does not move or rotate at the center in the width direction X, the elastic local buckling strength is increased. Therefore, the buckling stiffening structure 1 to which the present invention is applied. The effect of improving the local buckling strength was verified.

このように、本発明を適用した座屈補剛構造１は、中間板要素２の両側部２０から内側方向αに傾斜する傾斜部４が形成されるとともに、外側方向βに向けて突出するリブ部５が形成されることで、形鋼７等の板要素の局部座屈強度を向上させることが可能となる。また、本発明を適用した座屈補剛構造１は、単位断面積あたりの弾性局部座屈強度が向上し、単位延長あたりの弾性局部座屈強度が向上するため、傾斜部４及びリブ部５を幅方向Ｘに展開させた展開幅を抑制しながら、局部座屈強度を向上させることが可能となる。   As described above, the buckling stiffening structure 1 to which the present invention is applied is formed with the inclined portions 4 inclined in the inner direction α from the both side portions 20 of the intermediate plate element 2 and the ribs protruding toward the outer direction β. By forming the part 5, it becomes possible to improve the local buckling strength of the plate element such as the shape steel 7. In addition, the buckling stiffening structure 1 to which the present invention is applied improves the elastic local buckling strength per unit cross-sectional area and improves the elastic local buckling strength per unit extension. It is possible to improve the local buckling strength while suppressing the expanded width in which the width is expanded in the width direction X.

本発明を適用した座屈補剛構造１は、図６に示すように、中間板要素２の傾斜部４からリブ部５が最も突出する頂部５０まで、リブ部５の底部５１から頂部５０までを奥行方向Ｙで所定の突出高ｈとする。また、本発明を適用した座屈補剛構造１は、中間板要素２の両側部２０までを幅方向Ｘで所定の幅寸法ｂとして、中間板要素２を所定の板厚ｔとする。そして、局部座屈強度が確実に向上する範囲を検証するために、リブ部５の突出高ｈと中間板要素２の両側部２０までの幅寸法ｂとの望ましい関係を検討した。   As shown in FIG. 6, the buckling stiffening structure 1 to which the present invention is applied is from the inclined portion 4 of the intermediate plate element 2 to the top portion 50 where the rib portion 5 protrudes most, and from the bottom portion 51 of the rib portion 5 to the top portion 50. Is a predetermined protrusion height h in the depth direction Y. In the buckling stiffening structure 1 to which the present invention is applied, the intermediate plate element 2 is set to a predetermined thickness t in the width direction X up to both side portions 20 of the intermediate plate element 2, and the intermediate plate element 2 is set to a predetermined plate thickness t. Then, in order to verify the range in which the local buckling strength is reliably improved, a desirable relationship between the protrusion height h of the rib portion 5 and the width dimension b to the both side portions 20 of the intermediate plate element 2 was examined.

ここでは、リブ部５の頂部５０を仮想直線Ｓと一致させて、幅寸法ｂ／板厚ｔを一定（ｂ／ｔ＝８３）とした条件で、図９（ｂ）に示す比較例２のモデルと、図９（ｅ）に示す本発明例のモデルとを比較して、図９と同様の数値解析を実施した。この数値解析の結果によると、図１１に示すように、突出高ｈ／幅寸法ｂを横軸として、比較例２のモデルに対する本発明例のモデルでの局部座屈強度を縦軸とすると、０＜突出高ｈ／幅寸法ｂ≦０．１２の範囲で、局部座屈強度が確実に向上することがわかる。   Here, the top part 50 of the rib part 5 is made to correspond to the virtual straight line S, and the width dimension b / plate thickness t is constant (b / t = 83), and the comparative example 2 shown in FIG. The model and the model of the example of the present invention shown in FIG. 9E were compared, and the same numerical analysis as in FIG. 9 was performed. According to the result of this numerical analysis, as shown in FIG. 11, when the protrusion height h / width dimension b is the horizontal axis, and the local buckling strength in the model of the present invention example with respect to the model of Comparative Example 2 is the vertical axis, It can be seen that the local buckling strength is reliably improved in the range of 0 <projection height h / width dimension b ≦ 0.12.

また、幅寸法ｂ／板厚ｔを変化させた数値解析の結果によると、図１２（ａ）に示すように、幅寸法ｂ／板厚ｔを増減させることで、比較例２のモデルと本発明例のモデルとで局部座屈強度が一致する点（縦軸＝１となる丸囲い部分）が横軸方向に移動する。そして、縦軸＝１となる丸囲い部分は、幅寸法ｂ／板厚ｔが小さくなるにしたがって、突出高ｈ／幅寸法ｂが大きくなるように横軸方向に移動する。このとき、図１２（ａ）の縦軸＝１となる丸囲い部分は、図１２（ｂ）の実線に示すように、幅寸法ｂ／板厚ｔを横軸として、突出高ｈ／幅寸法ｂを縦軸とすると、ｈ／ｂ＝５．９９×（ｂ／ｔ）＾（−０．８７６）となる曲線上にプロットされる。そして、比較例２に対して本発明例の局部座屈強度が高くなる範囲は、図１２（ｂ）の実線以下の領域となる。   Further, according to the result of numerical analysis in which the width dimension b / plate thickness t is changed, as shown in FIG. 12A, by increasing / decreasing the width dimension b / plate thickness t, the model of the comparative example 2 and this The point where the local buckling strength matches with the model of the invention example (the circled portion where the vertical axis = 1) moves in the horizontal axis direction. The circled portion where the vertical axis = 1 is moved in the horizontal axis direction so that the protrusion height h / width dimension b increases as the width dimension b / plate thickness t decreases. At this time, as shown by the solid line in FIG. 12 (b), the rounded portion where the vertical axis = 1 in FIG. 12 (a) has a protruding height h / width dimension with the width dimension b / plate thickness t as the horizontal axis. If b is the vertical axis, it is plotted on a curve of h / b = 5.99 × (b / t) ^ (− 0.876). The range in which the local buckling strength of the example of the present invention is higher than that of Comparative Example 2 is a region below the solid line in FIG.

さらに、ＪＩＳ Ｇ ３３５０によると、中間板要素２と側部板要素３とがなす角度の許容誤差が±１．５°以下となるため、（ｂ／２）×（１．５°／１８０°×π）≦ｈの関係を満足することが必要となって、突出高ｈ／幅寸法ｂの下限値が０．０１３１となる。以上より、本発明を適用した座屈補剛構造１は、その中間板要素２において、リブ部５の突出高ｈと、中間板要素２の両側部２０までの幅寸法ｂとが、下記（１）式により規定される関係を満足することで、局部座屈強度を確実に向上させることが可能となる。   Further, according to JIS G 3350, since the tolerance of the angle formed by the intermediate plate element 2 and the side plate element 3 is ± 1.5 ° or less, (b / 2) × (1.5 ° / 180 ° Xπ) ≦ h must be satisfied, and the lower limit value of the protrusion height h / width dimension b is 0.0131. As described above, in the buckling stiffening structure 1 to which the present invention is applied, the protrusion height h of the rib portion 5 and the width dimension b to the both side portions 20 of the intermediate plate element 2 in the intermediate plate element 2 are as follows ( By satisfying the relationship defined by the equation (1), the local buckling strength can be reliably improved.

次に、図１３（ａ）に示すように、幅方向Ｘでリブ部５を所定の幅寸法ｂ_ribとして、ｂ_rib／ｂを変化させて図９と同様の数値解析を実施した。この数値解析の結果によると、図１３（ｂ）に示すように、リブ部５の幅寸法ｂ_ribの大きさにかかわらず、比較例２に対して本発明例の局部座屈強度が高くなる範囲はほとんど変化しないことがわかる。 Next, as shown in FIG. 13A, the same numerical analysis as in FIG. 9 was performed by changing _rib b / b with the rib portion 5 being a predetermined width dimension b _rib in the width direction X. According to the result of this numerical analysis, as shown in FIG. 13B, the local buckling strength of the present invention example is higher than that of the comparative example 2 regardless of the width dimension b _rib of the rib part 5. It can be seen that the range hardly changes.

次に、図１４（ａ）に示すように、リブ部５の頂部５０が仮想直線Ｓと一致する場合のリブ部５の突出高ｈを基準として、リブ部５の突出高ｈ２を変化させて図９と同様の数値解析を実施した。そして、図１４（ｂ）に示すように、（ｈ−ｈ２）／ｈを横軸として、突出高ｈに対する突出高ｈ２での局部座屈強度を縦軸とすると、（ｈ−ｈ２）／ｈ≒０となるときに、局部座屈強度が最大となることがわかる。このため、本発明を適用した座屈補剛構造１は、リブ部５が最も突出する頂部５０が仮想直線Ｓと略一致する位置（ｈ２≒ｈ）に配置されることで、局部座屈強度を効率的に向上させることが可能となる。   Next, as shown in FIG. 14A, the protrusion height h2 of the rib portion 5 is changed on the basis of the protrusion height h of the rib portion 5 when the top portion 50 of the rib portion 5 coincides with the virtual straight line S. Numerical analysis similar to FIG. 9 was performed. Then, as shown in FIG. 14B, when (h−h2) / h is taken as the horizontal axis and the local buckling strength at the projected height h2 relative to the projected height h is taken as the vertical axis, (h−h2) / h It can be seen that the local buckling strength is maximized when ≈0. For this reason, the buckling stiffening structure 1 to which the present invention is applied is arranged at a position (h2≈h) where the top portion 50 from which the rib portion 5 protrudes most substantially coincides with the virtual straight line S. Can be improved efficiently.

最後に、リブ部５が略三角形状に形成される場合と、図５（ａ）に示すように、リブ部５が略矩形状に形成される場合と、図５（ｂ）に示すように、リブ部５が略円弧状に形成される場合とで、各々の局部座屈強度を向上させる効果を検討した。このとき、図１５に示すように、比較例２のモデルに対する本発明例のモデルでの局部座屈強度を縦軸として示すと、リブ部５を略三角形状、略矩形状又は略円弧状の何れとした場合でも、縦軸の値が１を上回るため、局部座屈強度が十分に向上することがわかる。   Finally, when the rib portion 5 is formed in a substantially triangular shape, as shown in FIG. 5A, the rib portion 5 is formed in a substantially rectangular shape, and as shown in FIG. 5B. The effect of improving the local buckling strength was examined when the rib portion 5 was formed in a substantially arc shape. At this time, as shown in FIG. 15, when the local buckling strength in the model of the present invention with respect to the model of Comparative Example 2 is shown as the vertical axis, the rib portion 5 has a substantially triangular shape, a substantially rectangular shape, or a substantially arc shape. In any case, since the value on the vertical axis exceeds 1, it can be seen that the local buckling strength is sufficiently improved.

そして、本発明を適用した形鋼７は、図６〜図８に示すように、本発明を適用した座屈補剛構造１が設けられることで、所定の断面形状となる溝形鋼７１、ハット形鋼７２又はＺ形鋼７３の何れにおいても、中間板要素２の展開幅を抑制するとともに、局部座屈強度を向上させることが可能となる。   And, as shown in FIGS. 6 to 8, the shape steel 7 to which the present invention is applied is provided with the buckling stiffening structure 1 to which the present invention is applied. In either the hat-shaped steel 72 or the Z-shaped steel 73, it is possible to suppress the developed width of the intermediate plate element 2 and improve the local buckling strength.

なお、スチールハウス等の薄板軽量形鋼造建築物では、柱、梁又は根太その他のたて枠及びよこ枠の何れにおいても、主として、厚さ０．８ｍｍ以上、２．３ｍｍ未満の一枚の薄鋼板を、その強度を増強すべくロールフォーミングやプレスブレーキ等により曲げ加工して形成された溝形鋼７１等が使用されてもよい。   In addition, in a thin and light-weight steel structure such as a steel house, in any of a pillar, a beam, a joist or other vertical frame and a horizontal frame, a sheet of a thickness of 0.8 mm or more and less than 2.3 mm is mainly used. For example, groove steel 71 formed by bending a thin steel plate by roll forming, press brake or the like to enhance its strength may be used.

以上、本発明の実施形態の例について詳細に説明したが、上述した実施形態は、何れも本発明を実施するにあたっての具体化の例を示したものに過ぎず、これらによって本発明の技術的範囲が限定的に解釈されてはならない。   As mentioned above, although the example of embodiment of this invention was demonstrated in detail, all the embodiment mentioned above showed only the example of actualization in implementing this invention, and these are the technical aspects of this invention. The range should not be interpreted in a limited way.

１ ：座屈補剛構造
２ ：中間板要素
２０ ：両側部
２１ ：中間部
３ ：側部板要素
４ ：傾斜部
５ ：リブ部
５０ ：頂部
５１ ：底部
７ ：形鋼
７ａ ：ウェブ
７ｂ ：フランジ
７ｃ ：リップ
７ｄ ：アーム部
７１ ：溝形鋼
７２ ：ハット形鋼
７３ ：Ｚ形鋼
Ｓ ：仮想直線
α ：内側方向
β ：外側方向
Ｘ ：幅方向
Ｙ ：奥行方向
Ｚ ：材軸方向 1: Buckling stiffening structure 2: Intermediate plate element 20: Both sides 21: Intermediate portion 3: Side plate element 4: Inclined portion 5: Rib portion 50: Top portion 51: Bottom portion 7: Shaped steel 7a: Web 7b: Flange 7c: Lip 7d: Arm 71: Channel steel 72: Hat-shaped steel 73: Z-shaped steel S: Virtual straight line α: Inner direction β: Outer direction X: Width direction Y: Depth direction Z: Material axis direction

Claims (5)

所定の断面形状で形成された板要素に設けられる座屈補剛構造であって、
断面形状で幅方向に連続する中間板要素と、前記中間板要素の幅方向の両側部から屈曲して延びる一対の側部板要素とを備え、
一対の前記側部板要素は、前記中間板要素の幅方向の両側部から互いに略同一の方向に延びて形成されて、前記中間板要素の幅方向の両側部を結んだ仮想直線よりも一対の前記側部板要素が延びる方向が内側方向となって、
前記中間板要素は、幅方向の両側部から連続して前記内側方向に傾斜する傾斜部が形成されるとともに、前記傾斜部から前記内側方向の反対側となる外側方向に向けて突出するリブ部が幅方向の中間部に形成されること
を特徴とする座屈補剛構造。 A buckling stiffening structure provided in a plate element formed with a predetermined cross-sectional shape,
An intermediate plate element that is continuous in the width direction in cross-sectional shape, and a pair of side plate elements that bend and extend from both sides in the width direction of the intermediate plate element,
The pair of side plate elements are formed to extend from both sides in the width direction of the intermediate plate element in substantially the same direction, and are paired with an imaginary straight line connecting both sides in the width direction of the intermediate plate element. The direction in which the side plate element extends is the inner direction,
The intermediate plate element is formed with an inclined portion that inclines inward in the inner direction continuously from both sides in the width direction, and a rib portion that protrudes from the inclined portion toward the outer side opposite to the inner direction. A buckling stiffening structure characterized in that is formed in the middle in the width direction. 前記中間板要素及び一対の前記側部板要素は、前記中間板要素をウェブとするとともに前記側部板要素をフランジとする溝形鋼が用いられて、前記中間板要素の幅方向の両側部で、前記中間板要素と前記側部板要素とがなす屈曲角度θが９０°未満となること
を特徴とする請求項１記載の座屈補剛構造。 The intermediate plate element and the pair of side plate elements are made of grooved steel having the intermediate plate element as a web and the side plate element as a flange, and both side portions in the width direction of the intermediate plate element. The buckling stiffening structure according to claim 1, wherein a bending angle θ formed by the intermediate plate element and the side plate element is less than 90 °. 前記中間板要素は、前記傾斜部から前記リブ部が最も突出する頂部までの前記リブ部の突出高ｈと、幅方向の両側部までの幅寸法ｂとが、下記（１）式により規定される関係を満足すること
を特徴とする請求項１又は２記載の座屈補剛構造。

ここで、ｔ：前記中間板要素の板厚とする。 In the intermediate plate element, a protrusion height h of the rib portion from the inclined portion to the top where the rib portion protrudes most and a width dimension b to both side portions in the width direction are defined by the following expression (1). The buckling stiffening structure according to claim 1 or 2, wherein the following relationship is satisfied.

Here, t is the thickness of the intermediate plate element. 前記中間板要素は、前記傾斜部から前記リブ部が最も突出する頂部が、前記仮想直線と略一致する位置に配置されること
を特徴とする請求項１〜３の何れか１項記載の座屈補剛構造。 The seat according to any one of claims 1 to 3, wherein the intermediate plate element is arranged at a position where a top portion where the rib portion protrudes most from the inclined portion substantially coincides with the virtual straight line. Bending stiffening structure. 所定の断面形状で形成された板要素の座屈補剛構造が設けられる形鋼であって、
断面形状で幅方向に連続する中間板要素と、前記中間板要素の幅方向の両側部から屈曲して延びる一対の側部板要素とを備え、
前記中間板要素及び一対の前記側部板要素は、前記中間板要素をウェブとするとともに前記側部板要素をフランジとする溝形鋼、前記中間板要素をフランジとするとともに前記側部板要素をウェブとするハット形鋼、又は、前記中間板要素をフランジとするとともに前記側部板要素をウェブ若しくはリップとするＺ形鋼が用いられて、
一対の前記側部板要素は、前記中間板要素の幅方向の両側部から互いに略同一の方向に延びて形成されて、前記中間板要素の幅方向の両側部を結んだ仮想直線よりも一対の前記側部板要素が延びる方向が内側方向となって、
前記中間板要素は、幅方向の両側部から連続して前記内側方向に傾斜する傾斜部が形成されるとともに、前記傾斜部から前記内側方向の反対側となる外側方向に向けて突出するリブ部が幅方向の中間部に形成されること
を特徴とする形鋼。 A steel plate provided with a buckling stiffening structure for a plate element formed with a predetermined cross-sectional shape,
An intermediate plate element that is continuous in the width direction in cross-sectional shape, and a pair of side plate elements that bend and extend from both sides in the width direction of the intermediate plate element,
The intermediate plate element and the pair of side plate elements include a grooved steel having the intermediate plate element as a web and the side plate element as a flange, and the intermediate plate element as a flange and the side plate element. Or a Z-shape steel having a flange as the intermediate plate element and a web or lip as the side plate element,
The pair of side plate elements are formed to extend from both sides in the width direction of the intermediate plate element in substantially the same direction, and are paired with an imaginary straight line connecting both sides in the width direction of the intermediate plate element. The direction in which the side plate element extends is the inner direction,
The intermediate plate element is formed with an inclined portion that inclines inward in the inner direction continuously from both sides in the width direction, and a rib portion that protrudes from the inclined portion toward the outer side opposite to the inner direction. Is formed at the middle in the width direction.

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