JP2018161677A - Steel plate joint structure - Google Patents

Steel plate joint structure Download PDF

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JP2018161677A
JP2018161677A JP2017061199A JP2017061199A JP2018161677A JP 2018161677 A JP2018161677 A JP 2018161677A JP 2017061199 A JP2017061199 A JP 2017061199A JP 2017061199 A JP2017061199 A JP 2017061199A JP 2018161677 A JP2018161677 A JP 2018161677A
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plate
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JP6885136B2 (en
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耕一 横関
Koichi Yokozeki
耕一 横関
冨永 知徳
Noriyoshi Tominaga
知徳 冨永
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Nippon Steel Corp
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Nippon Steel and Sumitomo Metal Corp
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Abstract

PROBLEM TO BE SOLVED: To provide a steel plate joint structure capable of improving fatigue durability of a steel plate junction such as a gusset steel plate joint part without requiring additive processing/welding, by reducing a rigidity difference generated on a main plate.SOLUTION: The Young's modulus of an addition plate 2 is made smaller than the Young's modulus of a main plate 1 in the main stress direction of the main plate 1, and the main plate 1 has high Young's modulus in the main stress direction, and with this, it is possible to reduce a difference (rigidity difference) between a rigidity of a junction of the main plate 1 joined with the addition plate 2, and a rigidity of a part (general part) excluding the junction, not joined with the addition plate 2. Due to that a stress concentration ratio is reduced by rigidity difference reduction, and fatigue cracks hardly occur, fatigue durability of a steel plate junction such as a gusset steel plate joint can be improved without additively processing/welding.SELECTED DRAWING: Figure 1

Description

本発明は鋼板接合構造に関する。   The present invention relates to a steel plate joint structure.

構造体を構成する鋼板を補剛したり、この鋼板に他の部材を取りつけたりするために、構造体の鋼板には、この鋼板の板面から突出するように別の鋼板(ガセット鋼板等の付加板)が隅肉溶接によって接合されることで、ガセット溶接継手が形成されている場合がある(例えば特許文献1参照)。 このようなガセット溶接継手では、ガセット鋼板等の付加板が付加(接合)された主板の接合部分が、付加板の接合に起因して、付加板が付加(接合)されない部分より変形しにくいため、応力集中が起きる。繰返し応力変動下では、応力集中箇所から疲労き裂が発生し、この疲労き裂が構造物の耐久性を低下させる大きな原因となっている。特に、溶接接合が用いられる場合には、溶接によって形成される溶接止端や溶接ルート部といった形状急変部に局所的に応力が集中する上、溶接部には溶接によって導入された引張残留応力が存在しているため、疲労き裂が発生し易い状況にある。 既往の疲労対策技術として、鋼板どうしの溶接部の溶接止端に打撃処理等の止端処理を施すことにより、溶接止端の形状を応力が集中し難い滑らかな形状にするとともに、溶接止端およびその近傍の引張残留応力を緩和し、圧縮残留応力を付与する技術がある。その結果、溶接止端およびその近傍からのき裂の発生を防止し、疲労特性を改善することができる。   In order to stiffen the steel plate that constitutes the structure or to attach other members to this steel plate, the steel plate of the structure has another steel plate (such as a gusset steel plate) protruding from the plate surface of this steel plate. The gusset welded joint may be formed by joining the additional plate) by fillet welding (see, for example, Patent Document 1). In such a gusset welded joint, the joining portion of the main plate to which an additional plate such as a gusset steel plate is added (joined) is less likely to deform than the portion to which the additional plate is not added (joined) due to the joining of the additional plate. Stress concentration occurs. Under repeated stress fluctuations, fatigue cracks are generated from the stress concentration points, and this fatigue crack is a major cause of reducing the durability of the structure. In particular, when welded joints are used, stress is concentrated locally at the shape suddenly changing parts such as the weld toe and the weld root formed by welding, and the tensile residual stress introduced by welding is applied to the welded parts. Since it exists, it is in a situation where a fatigue crack is likely to occur. As a conventional fatigue countermeasure technology, the weld toe of the welded part between steel plates is subjected to a toe treatment such as a hammering process, so that the shape of the weld toe becomes a smooth shape in which stress is difficult to concentrate, and the weld toe In addition, there is a technique for relaxing compressive residual stress in the vicinity and applying compressive residual stress. As a result, generation of cracks from the weld toe and the vicinity thereof can be prevented, and fatigue characteristics can be improved.

特許第5085743号公報Japanese Patent No. 5085743

しかしながら、上述した疲労対策では、溶接止端からのき裂の発生は抑制されるが、溶接ルート部から繰返し荷重による疲労き裂を抑制することはできない。
このような溶接部の溶接ルート部からの疲労き裂の発生について、溶接部を完全溶込み溶接部にすれば、溶接ルート部がなくなるため疲労特性が向上するが、完全溶込み溶接を行う場合には、広範囲にわたって開先加工等の付加的な加工を施す必要があり、溶接作業に長時間を要し、溶接作業の負担が大きく、コストが増加する。
However, although the above-described fatigue measures suppress the generation of cracks from the weld toe, fatigue cracks due to repeated loads cannot be suppressed from the weld root portion.
Regarding the occurrence of fatigue cracks from the weld root part of such welds, if the weld part is made into a fully-penetrated weld part, the weld root part disappears and the fatigue characteristics are improved. Therefore, it is necessary to perform additional processing such as groove processing over a wide range, so that a long time is required for the welding operation, the burden of the welding operation is large, and the cost increases.

そこで本発明者は、ガセット鋼板等の付加板が付加(接合)される主板の接合部分の剛性が、付加板が接合されたために、付加板が付加(接合)されない接合部分以外の部分の剛性より高くなるため、この剛性差によって発生する応力集中が疲労き裂を引起していることに着目した。   Accordingly, the present inventor has found that the rigidity of the joined portion of the main plate to which an additional plate such as a gusset steel plate is added (joined) is the rigidity of the portion other than the joined portion to which the additional plate is not added (joined) because the additional plate is joined. In order to make it higher, we focused on the fact that the stress concentration generated by this difference in stiffness caused a fatigue crack.

本発明は、付加的な製作工程を要することなく、前記主板に生じる剛性差を減縮することで、ガセット鋼板継手部等の鋼板接合部の疲労耐久性を向上させることができる鋼板接合構造を提供することを目的とする。   The present invention provides a steel plate joining structure capable of improving the fatigue durability of steel plate joints such as gusset steel plate joints by reducing the difference in rigidity generated in the main plate without requiring an additional manufacturing process. The purpose is to do.

前記目的を達成するために、本発明の鋼板接合構造は、鋼板からなる主板に鋼板からなる付加板を接合してなる鋼板接合構造であって、
前記主板の主応力方向において、前記付加板のヤング率を前記主板のヤング率より小さくしたことを特徴とする。
ここで、主板の主応力方向とは、主板の継手部(付加板が接合される接合部)およびその近傍に作用する主応力の方向のことであり、以下では継手軸方向と称することもある。
In order to achieve the object, the steel plate joining structure of the present invention is a steel plate joining structure formed by joining an additional plate made of a steel plate to a main plate made of a steel plate,
In the main stress direction of the main plate, the Young's modulus of the additional plate is made smaller than the Young's modulus of the main plate.
Here, the main stress direction of the main plate refers to the direction of main stress acting on the joint portion of the main plate (joint portion to which the additional plate is joined) and its vicinity, and may be hereinafter referred to as the joint axial direction. .

本発明においては、主板の主応力方向(継手軸方向)において、付加板のヤング率を主板のヤング率より小さくしたので、付加板が接合される主板の接合部分の剛性と、付加板が接合されない接合部分以外の部分(一般部)の剛性との差(剛性差)を減縮することができる。剛性差を縮減することで応力集中率が低減し、疲労き裂を引起し難くなるので、付加的な加工・溶接をすることなく、ガセット鋼板継手部等の鋼板接合部の疲労耐久性を向上させることができる。   In the present invention, since the Young's modulus of the additional plate is smaller than the Young's modulus of the main plate in the main stress direction (joint axis direction) of the main plate, the rigidity of the joining portion of the main plate to which the additional plate is bonded and the additional plate are bonded. It is possible to reduce the difference (rigidity difference) from the rigidity of the portion (general portion) other than the joint portion that is not performed. By reducing the difference in stiffness, the stress concentration rate is reduced and fatigue cracks are less likely to occur, improving the fatigue durability of steel joints such as gusset steel joints without additional processing and welding. Can be made.

また、本発明の前記構成において、前記付加板を、当該付加板の第1の方向のヤング率と、当該第1の方向と直交する第2の方向のヤング率とが相互に異なる異方性鋼板とし、
前記付加板は、前記第1の方向と前記第2の方向とのうちヤング率が小さい方向を前記主板の主応力方向に向けた状態で前記主板に接合されていることが好ましい。
また、本発明の前記構成において、前記主板は、当該主板の主応力方向のヤング率が、当該主応力方向と直交する直交方向のヤング率よりも大きい異方性鋼板であることが好ましい。
In the configuration of the present invention, the additional plate may have anisotropy in which the Young's modulus in the first direction of the additional plate is different from the Young's modulus in the second direction orthogonal to the first direction. Steel plate,
It is preferable that the additional plate is joined to the main plate in a state in which a direction having a small Young's modulus of the first direction and the second direction is directed to the main stress direction of the main plate.
In the configuration of the present invention, the main plate is preferably an anisotropic steel plate in which the Young's modulus in the main stress direction of the main plate is larger than the Young's modulus in the orthogonal direction perpendicular to the main stress direction.

ここで、異方性鋼板とは、高ヤング率鋼板とも呼ばれ、部材の剛性を高めるために開発された鋼板を指し、強軸方向において、異方性を有しない普通鋼のヤング率(約205GPa程度)より高いヤング率、前記強軸方向と直交する弱軸方向に前記普通鋼のヤング率より低いヤング率を有する。従って前記付加板を異方性鋼板とする場合には、その弱軸方向(前記第1の方向と前記第2の方向とのうちヤング率が小さい方向)が前記主板の主応力方向(継手軸方向)と揃うように配置して、前記付加板を前記主板に接合することが好ましく、前記主板を異方性鋼板とする場合には、その強軸方向が前記主板の主応力方向(継手軸方向)に揃うように配置することが好ましい。   Here, the anisotropic steel plate is also referred to as a high Young's modulus steel plate, and refers to a steel plate developed to increase the rigidity of the member. In the strong axis direction, the Young's modulus (about approx. Higher Young's modulus) and a Young's modulus lower than that of the ordinary steel in the weak axis direction orthogonal to the strong axis direction. Therefore, when the additional plate is an anisotropic steel plate, the direction of the weak axis (the direction in which the Young's modulus is small between the first direction and the second direction) is the main stress direction (joint axis) of the main plate. The additional plate is preferably joined to the main plate, and when the main plate is an anisotropic steel plate, the strong axis direction is the main stress direction (joint axis) of the main plate. It is preferable to arrange them so that they are aligned in the direction).

前記付加板を異方性鋼板とし、その弱軸方向が主板の主応力方向(継手軸方向)と揃うように配置することで、主板の接合部を変形しにくくしている要因である付加板が継手軸方向に変形し易くなり、付加板が接合される主板の接合部分の剛性と、付加板が接合されない一般部分の剛性との差(剛性差)を減縮することができる。つまり、付加板に使用される高ヤング率鋼板(異方性鋼板)の副次的な特徴である低ヤング率を活用して、剛性差減縮により、応力集中を緩和させることで、疲労き裂を引起し難くなる。
特に主板と付加板とが溶接によって接合されている場合、主板と付加板との距離が最短となる溶接ルート部において、溶接止端に比して大きな応力集中低減効果が得られる。
加えて主板を、当該主板の主応力方向のヤング率が、当該主応力方向と直交する直交方向のヤング率よりも大きい異方性鋼板とすることで、より両部材(主板と付加板)の剛性差が縮まり、さらに応力集中低減が可能となる。
The additional plate is a factor that makes it difficult to deform the joint portion of the main plate by disposing the additional plate as an anisotropic steel plate and arranging the weak axis direction to be aligned with the main stress direction (joint axis direction) of the main plate. Can be easily deformed in the joint axial direction, and the difference (rigidity difference) between the rigidity of the joint portion of the main plate to which the additional plate is joined and the rigidity of the general portion to which the additional plate is not joined can be reduced. In other words, by utilizing the low Young's modulus, which is a secondary feature of high Young's modulus steel plates (anisotropic steel plates) used for additional plates, by reducing the stress concentration by reducing the stiffness difference, fatigue cracks are achieved. Is difficult to cause.
In particular, when the main plate and the additional plate are joined by welding, a large stress concentration reducing effect is obtained as compared with the weld toe at the welding root portion where the distance between the main plate and the additional plate is the shortest.
In addition, the main plate is made of an anisotropic steel plate in which the Young's modulus in the main stress direction of the main plate is larger than the Young's modulus in the orthogonal direction perpendicular to the main stress direction, so that both members (main plate and additional plate) The rigidity difference is reduced, and the stress concentration can be further reduced.

また、本発明の前記構成において、前記主板と前記付加板とが溶接部によって接合され、前記溶接部に止端処理が施されていてもよい。   Moreover, the said structure of this invention WHEREIN: The said main board and the said additional board may be joined by the welding part, and the toe end process may be given to the said welding part.

溶接部の溶接止端と溶接ルート部のどちらが先行して疲労損傷するかは、構造寸法および荷重状態に左右されるが、主板と付加板との溶接部に止端処理が施されているので、つまり、溶接止端の疲労強度を向上させる止端処理技術と剛性差縮減による応力集中率が低減技術を組み合わせることで、確実に溶接止端と溶接ルート部の両者を高疲労強度とすることができる。   Whether the weld toe or weld root of the welded part is subject to fatigue damage depends on the structural dimensions and load conditions, but the toe treatment is applied to the welded part of the main plate and the additional plate. In other words, by combining the toe treatment technology that improves the fatigue strength of the weld toe and the technology that reduces the stress concentration rate due to the reduction in rigidity difference, both the weld toe and the weld root part must be made to have high fatigue strength. Can do.

本発明によれば、主板の主応力方向において、付加板のヤング率を主板のヤング率より小さくすることによって、付加板が接合される主板の接合部分の剛性と、付加板が接合されない接合部分以外の部分(一般部)の剛性との差(剛性差)を減縮して、疲労き裂を起し難くなるので、付加的な加工・溶接をすることなく、ガセット鋼板継手部等の鋼板接合部の疲労耐久性を向上させることができる。   According to the present invention, in the main stress direction of the main plate, by making the Young's modulus of the additional plate smaller than the Young's modulus of the main plate, the rigidity of the bonded portion of the main plate to which the additional plate is bonded, and the bonded portion where the additional plate is not bonded Since the difference (stiffness difference) from the rigidity of other parts (general part) is reduced and fatigue cracks are less likely to occur, steel sheet joining such as gusset steel plate joints without additional processing or welding The fatigue durability of the part can be improved.

本発明の第1の実施の形態に係る鋼板接合構造を示すもので、斜視図である。BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing a steel plate joining structure according to a first embodiment of the present invention. 同、平面図である。FIG. 同、図2におけるA−A断面図である。FIG. 3 is a cross-sectional view taken along the line AA in FIG. 本発明に係る鋼板接構造のモデルを解析した結果を示すもので、ヤング率の変化率と応力との関係を示すグラフである。It is the graph which shows the result of having analyzed the model of the steel plate contact structure concerning the present invention, and shows the relation between the rate of change of Young's modulus, and stress. 本発明の第2の実施の形態に係る鋼板接合構造を示すもので、斜視図である。It is a perspective view which shows the steel plate junction structure concerning the 2nd Embodiment of this invention. 同、図5におけるB−B断面図である。FIG. 6 is a sectional view taken along line BB in FIG.

以下、図面を参照して本発明の実施の形態について説明する。
(第1の実施の形態)
図1は第1の実施の形態に係る鋼板接合構造を示す斜視図、図2は同平面図、図3は図2におけるA−A断面図である。
本実施の形態は、本発明の鋼板接合構造をガセット継手に適用した例であるが、本発明はこれに限ることはなく、他の鋼板接合構造に適用できる。
Embodiments of the present invention will be described below with reference to the drawings.
(First embodiment)
FIG. 1 is a perspective view showing a steel plate joining structure according to the first embodiment, FIG. 2 is a plan view thereof, and FIG. 3 is a cross-sectional view taken along line AA in FIG.
The present embodiment is an example in which the steel plate joint structure of the present invention is applied to a gusset joint, but the present invention is not limited to this and can be applied to other steel plate joint structures.

図1〜図3において、符号1は主板、符号2は主板1に接合される付加板を示す。主板1は鋼板からなるものであり、例えばH形鋼のウエブであり、付加板2は主板1より薄い鋼板からなるものであり、例えばH形鋼のウエブの一方の面に面外方向において溶接接合されたガセット鋼板である。なお、付加板2をウエブの他方の面にも接合してもよく、さらに、主板1と付加板2とは同厚にしてもよい。
ここで、本発明における「鋼板」とは鋼製の平板の他、例えば形鋼の一部のフランジやウエブ、さらには、鋼製部材を構成する板状の鋼材を含むものである。
1 to 3, reference numeral 1 denotes a main plate, and reference numeral 2 denotes an additional plate joined to the main plate 1. The main plate 1 is made of a steel plate, for example, an H-shaped steel web, and the additional plate 2 is made of a steel plate thinner than the main plate 1, and is welded to one surface of the H-shaped steel web, for example, in an out-of-plane direction. It is a bonded gusset steel plate. Note that the additional plate 2 may be joined to the other surface of the web, and the main plate 1 and the additional plate 2 may have the same thickness.
Here, the “steel plate” in the present invention includes, in addition to a flat plate made of steel, for example, some flanges and webs of shaped steel, and further a plate-shaped steel material constituting a steel member.

主板1は、矩形板状に形成された異方性鋼板(高ヤング率鋼板)であり、図1においてX方向(一方向)、つまり主板1の主応力方向において、異方性を有しない普通鋼のヤング率より高いヤング率(高ヤング率)を有し、X方向と直交するY方向(直交方向)において、異方性を有しない普通鋼のヤング率より低いヤング率(低ヤング率)を有している。
X方向は、主板1の継手部(付加板2が接合される接合部)およびその近傍に作用する応力の主応力方向(継手軸方向)であり、主板1の材軸方向である。Y方向は材軸方向と直交する方向である。
付加板2は、当該付加板2の第1の方向(X方向)のヤング率と、当該第1の方向と直交する第2の方向(Z方向)のヤング率とが相互に異なる矩形板状に形成された異方性鋼板(高ヤング率鋼板)であり、図1においてX方向(一方向)において、異方性を有しない普通鋼のヤング率より低いヤング率(低ヤング率)を有し、X方向と直交するZ方向(直交方向)において、異方性を有しない普通鋼のヤング率より高いヤング率(高ヤング率)を有している。つまり、付加板2はZ方向が高剛性方向(強軸方向)であり、主板1はX方向が高剛性方向(強軸方向)である。Z方向は主板1の上面と直交する面内において、付加板2の材軸方向と直交する方向である。
The main plate 1 is an anisotropic steel plate (high Young's modulus steel plate) formed in the shape of a rectangular plate, and has no anisotropy in the X direction (one direction), that is, the main stress direction of the main plate 1 in FIG. Young's modulus higher than the Young's modulus of steel (high Young's modulus) and lower in Young's modulus (low Young's modulus) than ordinary steel without anisotropy in the Y direction (orthogonal direction) perpendicular to the X direction have.
The X direction is the main stress direction (joint axis direction) of the stress acting on the joint portion of the main plate 1 (joint portion to which the additional plate 2 is joined) and its vicinity, and is the material axis direction of the main plate 1. The Y direction is a direction orthogonal to the material axis direction.
The additional plate 2 has a rectangular plate shape in which the Young's modulus in the first direction (X direction) of the additional plate 2 is different from the Young's modulus in the second direction (Z direction) orthogonal to the first direction. An anisotropic steel plate (high Young's modulus steel plate) formed in the shape shown in FIG. 1, which has a Young's modulus (low Young's modulus) lower than that of ordinary steel having no anisotropy in the X direction (one direction) in FIG. In the Z direction (orthogonal direction) perpendicular to the X direction, the Young's modulus (high Young's modulus) is higher than that of ordinary steel having no anisotropy. That is, the additional plate 2 has a high rigidity direction (strong axis direction) in the Z direction, and the main plate 1 has a high rigidity direction (strong axis direction) in the X direction. The Z direction is a direction orthogonal to the material axis direction of the additional plate 2 in a plane orthogonal to the upper surface of the main plate 1.

そして、付加板2はヤング率が小さい方向を主板1のヤング率が高い主応力方向Xに向けて主板1に接合されている。すなわち、主板1の高ヤング率を有する方向(X方向)と、付加板2の低ヤング率を有する方向(X方向)とを一致させて溶接接合されている。
また、付加板2は主板1の面外方向において当該主板1と直角に溶接接合されている。
The additional plate 2 is joined to the main plate 1 with the direction in which the Young's modulus is small directed toward the main stress direction X in which the Young's modulus of the main plate 1 is high. That is, the direction of the main plate 1 having a high Young's modulus (X direction) and the direction of the additional plate 2 having a low Young's modulus (X direction) are aligned by welding.
The additional plate 2 is welded to the main plate 1 at a right angle in the out-of-plane direction of the main plate 1.

ここで、主応力方向(この実施の形態の場合はX方向)において、付加板2のヤング率は、主板1のヤング率より5%以上小さくすることが好ましい。
これは、普通鋼のヤング率が一定値でなく、分布を有することが理由であり、普通鋼を用いた場合においても、付加板2のX方向(主応力方向)におけるヤング率と、主板1のX方向(主応力方向)におけるヤング率に5%程度までの差が生じる場合があるためである。したがって、普通鋼を用いた継手の疲労寿命はある程度の分布を有することになるが、設計等では疲労寿命の分布の下限をもって継手の性能を評価することが必要となる。このため、本発明による継手に、普通鋼を用いた従来の継手よりも明確且つ安定的に高い性能を付与するためには、付加板2のX方向(主応力方向)におけるヤング率は、主板1のX方向(主応力方向)におけるヤング率より5%以上小さくすることが好ましい。
Here, in the main stress direction (X direction in the case of this embodiment), it is preferable that the Young's modulus of the additional plate 2 is 5% or less smaller than the Young's modulus of the main plate 1.
This is because the Young's modulus of ordinary steel is not a constant value but has a distribution. Even when ordinary steel is used, the Young's modulus in the X direction (main stress direction) of the additional plate 2 and the main plate 1 This is because a difference of up to about 5% may occur in the Young's modulus in the X direction (main stress direction). Therefore, although the fatigue life of a joint using ordinary steel has a certain distribution, it is necessary to evaluate the performance of the joint with the lower limit of the fatigue life distribution in design and the like. For this reason, in order to give the joint according to the present invention a clearer and more stable performance than the conventional joint using ordinary steel, the Young's modulus in the X direction (main stress direction) of the additional plate 2 is The Young's modulus in the X direction (main stress direction) of 1 is preferably 5% or more smaller.

また、主板1と付加板2との溶接接合は、付加板2の基端部と主板1の表面(上面)とを隅肉溶接によって全周溶接することによって行われている。この溶接部3は例えばアーク溶接によって横断面直角三角形状に形成されている。なお、溶接は全周溶接に限らず、断続溶接や、点溶接(スポット溶接)であってもよい。
また、溶接部3には止端処理が施されている。止端処理としては、例えば、溶接止端3aにグラインダー処理、TIGドレッシング処理、化粧盛り溶接などを施して溶接止端3aの曲率を大きくする方法や、溶接後熱処理による溶接止端3aの引張残留応力を低減する方法、もしくは溶接止端3aにショットピーニング、ハンマーピーニング、レーザーピーニング、ウォータージェットピーニング、超音波打撃処理などの機械的打撃処理施すことで上記の両者の効果、すなわち、溶接止端3aの曲率を大きくし、かつ引張残留応力を低減する方法がある。
The main plate 1 and the additional plate 2 are welded and joined by welding the base end of the additional plate 2 and the surface (upper surface) of the main plate 1 all around by fillet welding. The welded portion 3 is formed in a triangular shape having a transverse cross section by, for example, arc welding. In addition, welding is not limited to all-around welding, but may be intermittent welding or spot welding (spot welding).
Further, the welded portion 3 is subjected to a toe end treatment. As the toe treatment, for example, a method of increasing the curvature of the weld toe 3a by applying a grinder process, a TIG dressing process, a decorative welding or the like to the weld toe 3a, or a tensile residual of the weld toe 3a by heat treatment after welding. The effect of both of the above-described effects, that is, the weld toe 3a, is obtained by applying a mechanical hitting process such as shot peening, hammer peening, laser peening, water jet peening, ultrasonic hitting to the weld toe 3a. There is a method for increasing the curvature and reducing the tensile residual stress.

以上のように本実施の形態によれば、付加板2は主板1の主応力方向(継手軸方向)に低ヤング率を有するとともに、付加板2の主応力方向(X方向)のヤング率を主板1の主応力方向(X方向)のヤング率より小さくし、さらに、主板1は主応力方向(X方向)に高ヤング率を有するので、付加板2が接合される主板1の接合部分の剛性と、付加板2が接合されない接合部分以外の部分(一般部分)の剛性との差(剛性差)を減縮することができる。
このように剛性差縮減により応力集中率が低減し、疲労き裂を引起し難くなるので、付加的な加工・溶接をすることなく、ガセット鋼板継手部等の鋼板接合部の疲労耐久性を向上させることができる。
また、溶接部3の溶接止端3aと溶接ルート部3bのどちらが先行して疲労損傷するかは、構造寸法および荷重状態に左右されるが、主板1と付加板2との溶接部3に止端処理が施されているので、つまり、溶接止端3aの疲労強度を向上させる止端処理技術と剛性差縮減による応力集中率が低減技術を組み合わせることで、確実に溶接止端3aと溶接ルート部3bの両者を高疲労強度とすることができる。
As described above, according to the present embodiment, the additional plate 2 has a low Young's modulus in the main stress direction (joint axis direction) of the main plate 1 and the Young's modulus in the main stress direction (X direction) of the additional plate 2. Since the Young's modulus of the main plate 1 is smaller than the Young's modulus in the main stress direction (X direction), and the main plate 1 has a high Young's modulus in the main stress direction (X direction), the joining portion of the main plate 1 to which the additional plate 2 is joined A difference (rigidity difference) between the rigidity and the rigidity of a part (general part) other than the joined part where the additional plate 2 is not joined can be reduced.
In this way, the stress concentration rate is reduced by reducing the stiffness difference, and fatigue cracks are less likely to occur, so the fatigue durability of steel joints such as gusset steel joints is improved without additional processing and welding. Can be made.
Further, which of the weld toe 3a and the weld root 3b of the welded part 3 is subject to fatigue damage in advance depends on the structural dimensions and the load state, but the welded part 3 between the main plate 1 and the additional plate 2 is stopped. Since end treatment is performed, that is, by combining the toe treatment technology for improving the fatigue strength of the weld toe 3a and the technology for reducing the stress concentration rate due to the reduction in rigidity difference, the weld toe 3a and the welding route are surely combined. Both of the parts 3b can have high fatigue strength.

次に、図1に示す鋼板接合構造と同様の構成のモデルについてソリッド要素有限要素法によって解析した結果について説明する。
まず、主板および付加板とも異方性鋼板(高ヤング率鋼板)とした場合、主板は、図1に示すように主応力方向(X方向)に高剛性(高ヤング率)、付加板は主応力方向(X方向)に低剛性(低ヤング率)としている。
また、付加板のみ異方性鋼板(高ヤング率鋼板)とした場合、付加板は主応力方向(X方向)に低剛性(低ヤング率)としている。
高ヤング率鋼板のヤング率については、通常の普通鋼板のヤング率を205GPaとすると、通常の鋼板のヤング率(205GPa)より、高ヤング率側で+5〜+25%(5〜25%高い)、低ヤング率側で−5〜−25%(5〜25%低い)としている。ポアソン比は0.3としている。ここで、普通鋼は異方性を有せず、鋼板面内の何れの方向にも等しいヤング率を有するとする。
また、主板と付加板とは双方とも厚さを25mmとし、隅肉溶接によって全周溶接し、溶接脚長は8mmとしている。
Next, the result of analyzing the model having the same configuration as the steel plate joint structure shown in FIG. 1 by the solid element finite element method will be described.
First, when both the main plate and the additional plate are anisotropic steel plates (high Young's modulus steel plates), the main plate has high rigidity (high Young's modulus) in the main stress direction (X direction) as shown in FIG. Low rigidity (low Young's modulus) in the stress direction (X direction).
When only the additional plate is an anisotropic steel plate (high Young's modulus steel plate), the additional plate has low rigidity (low Young's modulus) in the main stress direction (X direction).
Regarding the Young's modulus of the high Young's modulus steel plate, if the Young's modulus of a normal ordinary steel plate is 205 GPa, the Young's modulus of the normal steel plate (205 GPa) is +5 to + 25% (5 to 25% higher) on the high Young's modulus side, The lower Young's modulus side is -5 to -25% (5 to 25% lower). The Poisson's ratio is 0.3. Here, it is assumed that ordinary steel does not have anisotropy and has an equal Young's modulus in any direction within the plane of the steel sheet.
Further, both the main plate and the additional plate have a thickness of 25 mm, are welded all around by fillet welding, and have a weld leg length of 8 mm.

解析結果を図4に示す。図4に示すグラフでは、縦軸を普通鋼による継手の結果で標準化(鋼板接合部の応力を普通鋼による継手の応力で除した値)した応力低減率とし、横軸を異方性鋼板のヤング率の普通鋼に比した変化率としている。
また、図4に示すグラフにおいて、「●」は、主板、付加板の双方が異方性鋼板(高ヤング率鋼板)の場合における溶接ルート部の応力、「〇」は主板、付加板の双方が異方性鋼板(高ヤング率鋼板)の場合における溶接止端の応力、「▲」は付加板のみが異方性鋼板(高ヤング率鋼板)の場合における溶接ルート部の応力、「△」は付加板のみが異方性鋼板(高ヤング率鋼板)の場合における溶接止端の応力を示す。
なお、図4のグラフにおいて、横軸のヤング率の変化率が「0」、縦軸の応力が「1.00」の点は、普通鋼で形成された主板に普通鋼で形成された付加板を溶接接合した場合を示す。
The analysis results are shown in FIG. In the graph shown in FIG. 4, the vertical axis is the stress reduction rate normalized by the result of the joint made of ordinary steel (the value obtained by dividing the stress of the steel plate joint by the stress of the joint made of ordinary steel), and the horizontal axis is the anisotropic steel plate. Change rate of Young's modulus compared to ordinary steel.
In the graph shown in FIG. 4, “●” indicates the stress in the weld root when both the main plate and the additional plate are anisotropic steel plates (high Young's modulus steel plates), and “◯” indicates both the main plate and the additional plate. Is the stress at the weld toe when an anisotropic steel plate (high Young's modulus steel plate), "▲" is the stress at the weld root when only the additional plate is an anisotropic steel plate (high Young's modulus steel plate), "△" Indicates the stress at the weld toe when only the additional plate is an anisotropic steel plate (high Young's modulus steel plate).
In the graph of FIG. 4, the change rate of Young's modulus on the horizontal axis is “0” and the stress on the vertical axis is “1.00” is the addition of the main plate made of plain steel and made of plain steel. The case where the plate is welded is shown.

図4のグラフから明らかなように、溶接止端と溶接ルート部の双方とも、ヤング率の変化率が大きくなるほど応力が小さくなることが分かる。すなわち、ヤング率の変化率が大きくなるほど、上述した剛性差が小さくなるので、この剛性差縮減により応力集中率が低減することがわかる。
特に、溶接止端より溶接ルート部の方がヤング率の変化率が大きいほど、応力が低くなるので、溶接ルート部の応力集中率の低減に有効である。
また、主板および付加板とも異方性鋼板(高ヤング率鋼板)とした場合の方が付加板のみ異方性鋼板(高ヤング率鋼板)とした場合に比して応力が低くなるので、主板および付加板とも異方性鋼板(高ヤング率鋼板)とした方が応力集中率の低減に有効である。
As is clear from the graph of FIG. 4, it can be seen that the stress decreases as the rate of change in Young's modulus increases in both the weld toe and the weld root. That is, as the rate of change of Young's modulus increases, the above-described stiffness difference decreases, and it can be understood that the stress concentration rate is reduced by reducing the stiffness difference.
In particular, the greater the rate of change in Young's modulus at the weld root than at the weld toe, the lower the stress, which is effective in reducing the stress concentration rate at the weld root.
In addition, when the main plate and the additional plate are both anisotropic steel plates (high Young's modulus steel plates), the stress is lower than when only the additional plates are anisotropic steel plates (high Young's modulus steel plates). In addition, it is more effective to reduce the stress concentration rate by using anisotropic steel plates (high Young's modulus steel plates) for the additional plates.

(第2の実施の形態)
図5は第2の実施の形態に係る鋼板接合構造を示す斜視図、図6は図5におけるB−B断面図である。
本実施の形態が第1の実施の形態と異なる点は、付加板12を主板11の端面(こば面)に溶接接合した点である。
主板11は鋼板からなるものであり、例えばH形鋼のフランジである。付加板12は主板11より薄い鋼板からなるものであり、例えばH形鋼のフランジに面内方向において溶接接合されたガセット鋼板である。
(Second Embodiment)
FIG. 5 is a perspective view showing a steel plate joining structure according to the second embodiment, and FIG. 6 is a cross-sectional view taken along line BB in FIG.
The difference between the present embodiment and the first embodiment is that the additional plate 12 is welded to the end surface (rib surface) of the main plate 11.
The main plate 11 is made of a steel plate, for example, an H-shaped flange. The additional plate 12 is made of a steel plate that is thinner than the main plate 11, and is, for example, a gusset steel plate that is welded and joined in the in-plane direction to a flange of an H-shaped steel.

主板11は、矩形板状に形成された異方性鋼板(高ヤング率鋼板)であり、図5においてY方向(一方向)、つまり主応力方向において、異方性を有しない普通鋼のヤング率より高いヤング率(高ヤング率)を有し、Y方向と直交するX方向(直交方向)において、異方性を有しない普通鋼のヤング率より低いヤング率(低ヤング率)を有している。
付加板12は、矩形板状に形成された異方性鋼板(高ヤング率鋼板)であり、図5においてY方向(一方向)において、異方性を有しない普通鋼のヤング率より低いヤング率(低ヤング率)を有し、Y方向と直交するX方向(直交方向)において、異方性を有しない普通鋼のヤング率より高いヤング率(高ヤング率)を有している。つまり、付加板12はX方向が高剛性方向であり、主板1はY方向が高剛性方向である。
The main plate 11 is an anisotropic steel plate (high Young's modulus steel plate) formed in the shape of a rectangular plate. In FIG. 5, the normal steel Young having no anisotropy in the Y direction (one direction), that is, the main stress direction. Young's modulus (high Young's modulus) higher than the modulus, and in the X direction (orthogonal direction) perpendicular to the Y direction, the Young's modulus (low Young's modulus) is lower than that of ordinary steel having no anisotropy ing.
The additional plate 12 is an anisotropic steel plate (high Young's modulus steel plate) formed in the shape of a rectangular plate, and has a Young's modulus lower than that of ordinary steel having no anisotropy in the Y direction (one direction) in FIG. In the X direction (orthogonal direction) perpendicular to the Y direction, the Young's modulus (high Young's modulus) is higher than that of ordinary steel having no anisotropy. That is, the X direction of the additional plate 12 is a highly rigid direction, and the Y direction of the main plate 1 is a highly rigid direction.

そして、付加板12はヤング率が小さい方向を主板11のヤング率が高い主応力方向Yに向けて主板11に接合されている。すなわち、主板11の高ヤング率を有する方向(Y方向)と、付加板12の低ヤング率を有する方向(Y方向)とを一致させて溶接接合されている。
また、付加板12のY方向(主応力方向)におけるヤング率は、主板1のY方向(主応力方向)におけるヤング率より小さくなっている。なお、主応力方向において、付加板12のヤング率は、主板1のヤング率より5%以上小さいことが好ましいことは、第1の実施の形態と同じである。
さらに、付加板12は主板11の面内方向において当該主板11の端面(こば面)と直角に溶接接合されている。
The additional plate 12 is joined to the main plate 11 with the direction in which the Young's modulus is small directed toward the main stress direction Y in which the Young's modulus of the main plate 11 is high. That is, the direction of the main plate 11 having a high Young's modulus (Y direction) and the direction of the additional plate 12 having a low Young's modulus (Y direction) are aligned by welding.
Further, the Young's modulus in the Y direction (main stress direction) of the additional plate 12 is smaller than the Young's modulus in the Y direction (main stress direction) of the main plate 1. Note that, in the main stress direction, the Young's modulus of the additional plate 12 is preferably 5% or more smaller than the Young's modulus of the main plate 1 as in the first embodiment.
Further, the additional plate 12 is welded and joined at a right angle to the end surface (rib surface) of the main plate 11 in the in-plane direction of the main plate 11.

また、主板11と付加板12との溶接接合は、付加板12の基端部と主板11の端面(こば面)とを隅肉溶接によって全周溶接することによって行われている。この溶接部13はアーク溶接によって横断面直角三角形状に形成されている。さらに、溶接部13には上述した溶接部3と同様の止端処理が施されている。   Further, the welding connection between the main plate 11 and the additional plate 12 is performed by welding the base end portion of the additional plate 12 and the end surface (rib surface) of the main plate 11 all around by fillet welding. The welded portion 13 is formed in a triangular shape having a transverse cross section by arc welding. Further, the welded portion 13 is subjected to the same toe stop treatment as that of the welded portion 3 described above.

本実施の形態によれば、第1の実施の形態と同様に、付加板12は主応力方向に低ヤング率を有するとともに、付加板12の主応力方向(Y方向)のヤング率を主板11の主応力方向(X方向)のヤング率より小さくし、さらに、主板11は主応力方向(Y方向)に高ヤング率を有するので、付加板12が接合される主板11の接合部分の剛性と、付加板12が接合されない接合部分以外の部分(一般部分)の剛性との差(剛性差)を減縮することができる。
このように剛性差縮減により応力集中率が低減し、疲労き裂を引起し難くなるので、付加的な加工・溶接をすることなく、ガセット鋼板継手部等の鋼板接合部の疲労耐久性を向上させることができる。
また、第1の実施の形態と同様に、溶接止端13aの疲労強度を向上させる止端処理技術と剛性差縮減による応力集中率が低減技術を組み合わせることで、確実に溶接止端13aと溶接ルート部13bの両者を高疲労強度とすることができる。
According to the present embodiment, as in the first embodiment, the additional plate 12 has a low Young's modulus in the main stress direction and the Young's modulus in the main stress direction (Y direction) of the additional plate 12. Since the main plate 11 has a high Young's modulus in the main stress direction (Y direction), the rigidity of the joined portion of the main plate 11 to which the additional plate 12 is joined is smaller than the Young's modulus in the main stress direction (X direction). The difference (rigidity difference) from the rigidity of the part (general part) other than the joined part where the additional plate 12 is not joined can be reduced.
In this way, the stress concentration rate is reduced by reducing the stiffness difference, and fatigue cracks are less likely to occur, so the fatigue durability of steel joints such as gusset steel joints is improved without additional processing and welding. Can be made.
Similarly to the first embodiment, by combining a toe processing technique for improving the fatigue strength of the weld toe 13a and a technique for reducing the stress concentration rate due to the reduction in rigidity difference, the weld toe 13a and the welding tough are reliably connected. Both the root portions 13b can have high fatigue strength.

なお、第1および第2の実施の形態では、本発明の鋼板接合構造を主板1,11と付加板2,12とを溶接によって接合されている場合を例にとって説明したが、本発明は溶接接合に限らず、例えば摩擦撹拌接合や高力ボルト接合等によって主板1,11と付加板2,12とを接合する場合も適用できる。
また、第1および第2の実施の形態では、主板1,11と付加板2,12の双方を異方性鋼板(高ヤング率鋼板)としたが、付加板2,12のみを異方性鋼板(高ヤング率鋼板)としてもよい。
In the first and second embodiments, the steel plate joining structure of the present invention has been described by taking as an example the case where the main plates 1 and 11 and the additional plates 2 and 12 are joined by welding. Not only joining but also the case where the main plates 1 and 11 and the additional plates 2 and 12 are joined by, for example, friction stir welding or high-strength bolt joining can be applied.
In the first and second embodiments, both the main plates 1 and 11 and the additional plates 2 and 12 are anisotropic steel plates (high Young's modulus steel plates), but only the additional plates 2 and 12 are anisotropic. It is good also as a steel plate (high Young's modulus steel plate).

また、第1および第2の実施の形態では、主板1,11の高剛性方向(強軸方向)と、付加板2,12の低剛性方向(弱軸方向)とが一致しているが、本発明はこれに限ることはない。要は主板の主応力方向(継手軸方向)において、付加板のヤング率を主板のヤング率より小さくして、主板に付加板を接合すればよい。この場合、主板や付加板の高剛性方向・低剛性方向は関係ない。
また、第1の実施の形態では、図1に示すように、主板1の材軸方向と付加板2の材軸方向とが同じX方向であるが、主板1の材軸方向と付加板2の材軸方向が水平方向において直交していてもよい。
In the first and second embodiments, the high rigidity direction (strong axis direction) of the main plates 1 and 11 and the low rigidity direction (weak axis direction) of the additional plates 2 and 12 are the same. The present invention is not limited to this. In short, in the main stress direction (joint axis direction) of the main plate, the additional plate may be joined to the main plate by making the Young's modulus of the additional plate smaller than the Young's modulus of the main plate. In this case, the high rigidity direction and the low rigidity direction of the main plate and the additional plate are not relevant.
Further, in the first embodiment, as shown in FIG. 1, the material axis direction of the main plate 1 and the material axis direction of the additional plate 2 are the same X direction. The material axis directions may be orthogonal in the horizontal direction.

1,11 主板
2,12 付加板
3,13 溶接部
3a,13a 溶接止端
3b,13b 溶接ルート部
1,11 Main plate 2,12 Additional plate 3,13 Weld 3a, 13a Weld toe 3b, 13b Weld root

Claims (4)

鋼板からなる主板に鋼板からなる付加板を接合してなる鋼板接合構造であって、
前記主板の主応力方向において、前記付加板のヤング率を前記主板のヤング率より小さくしたことを特徴とする鋼板接合構造。
A steel plate joining structure formed by joining an additional plate made of a steel plate to a main plate made of a steel plate,
A steel plate joining structure, wherein a Young's modulus of the additional plate is smaller than a Young's modulus of the main plate in a main stress direction of the main plate.
前記付加板を、当該付加板の第1の方向のヤング率と、当該第1の方向と直交する第2の方向のヤング率とが相互に異なる異方性鋼板とし、
前記付加板は、前記第1の方向と前記第2の方向とのうちヤング率が小さい方向を前記主板の主応力方向に向けた状態で前記主板に接合されていることを特徴とする請求項1に記載の鋼板接合構造。
The additional plate is an anisotropic steel plate in which the Young's modulus in the first direction of the additional plate and the Young's modulus in the second direction orthogonal to the first direction are different from each other,
The said additional board is joined to the said main board in the state which orient | assigned the direction with a small Young's modulus among the said 1st direction and the said 2nd direction to the main stress direction of the said main board. 1. A steel plate joint structure according to 1.
前記主板は、当該主板の主応力方向のヤング率が、当該主応力方向と直交する直交方向のヤング率よりも大きい異方性鋼板であることを特徴とする請求項1または2に記載の鋼板接合構造。   3. The steel plate according to claim 1, wherein the main plate is an anisotropic steel plate having a Young's modulus in a main stress direction of the main plate larger than a Young's modulus in a direction orthogonal to the main stress direction. Junction structure. 前記主板と前記付加板とが溶接部によって接合され、
前記溶接部に止端処理が施されていることを特徴とする請求項1〜3のいずれか1項に記載の鋼板接合構造。
The main plate and the additional plate are joined by a weld,
The steel plate joining structure according to any one of claims 1 to 3, wherein a toe end treatment is applied to the welded portion.
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JP2020020128A (en) * 2018-07-31 2020-02-06 日本製鉄株式会社 Steel plate floor
JP2020157329A (en) * 2019-03-26 2020-10-01 日本製鉄株式会社 Weld joint

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JP2016014306A (en) * 2014-07-03 2016-01-28 茂己 山本 Welded structure for steel structure

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JP2020020128A (en) * 2018-07-31 2020-02-06 日本製鉄株式会社 Steel plate floor
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