DOI： 10.11532/structcivil.69A.500

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DOI： 10.11532/structcivil.69A.116

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DOI： 10.11532/structcivil.69A.953

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Japan Society of Civil Engineers  

DOI： 10.2208/jscejj.22-00143

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Institute of Electrical and Electronics Engineers (IEEE)  

DOI： 10.1109/tmag.2022.3151656

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DOI： 10.2208/jscejseee.77.2_333

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DOI： 10.2208/jscejam.77.2_I_371

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DOI： 10.2208/jscejseee.77.1_59

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DOI： 10.2208/jscejam.76.2_I_89

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DOI： 10.2208/jscejseee.76.2_239

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DOI： 10.11532/structcivil.66A.868

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Japan Society of Civil Engineers  

DOI： 10.2208/jscejseee.76.5_ii_38

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1201/9780429279119-234

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DOI： 10.11532/structcivil.65A.755

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.11532/structcivil.65A.745

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Japan Society of Civil Engineers  

DOI： 10.2208/jscejam.75.2_i_571

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：KOREAN SOC STEEL CONSTRUCTION-KSSC  

DOI： 10.1007/s13296-018-0106-y

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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掲載種別：研究論文（学術雑誌）  

Fatigue tests and numerical analyses were carried out in order to investigate the effect of hammer peening on fatigue life of U-rib structure. The fatigue test results showed that the fatigue life of peened specimens are longer than the non-peened ones. In addition, the numerical results showed that compressive residual stresses were induced at weld toe and root by hammer peening, moreover that the accumulated plastic strains during cyclic loading can explain the experimental results in terms of fatigue life extension.

DOI： 10.2207/QJJWS.35.169S

Scopus

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：KOREAN SOC STEEL CONSTRUCTION-KSSC  

In steel members strengthened by carbon-fiber reinforced polymer (CFRP) plates, the thermal stresses are introduced in the steel members, the CFRP plates and the adhesive layers when temperature changes because the linear thermal expansion coefficients of steel and CFRP are mismatched As so far, the authors proposed a technique to reduce the thermal stress in steel members strengthened by CFRP plates, which involves bonding aluminum alloy plates with CFRP plates. In the proposed method, the thermal stress in steel member can be reduced so that there are negligible levels of stress in steel member when the cross sectional areas of CFRP and aluminum plates are designed to correspond to the coefficient of thermal expansion of steel, even though the thermal stresses are introduced in the CFRP and aluminum plates. In this study, to confirm the maintaining the thermal stress reduction in steel member by proposed method, thermal stress measurement in steel plate strengthened by CFRP and aluminum plates was carried out about 21 months. In this research, the thermal stress introduced in the steel plate strengthened by CFRP plates was also measured. Furthermore, to assume the thermal shear and normal (peel) stresses in adhesive layers, FE analysis with plane stress element was employed. As the result, it was shown the thermal stresses in steel plate with CFRP plate were able to calculate by using composite theory and measured temperature. Furthermore, in steel plate strengthened by CFRP and aluminum plates, the thermal stress introduced in steel plate was negligible-small through the all-season. It was found the thermal stresses in steel plate with CFRP plates as well as CFRP and aluminum plates were also estimated by using composite theory and measured temperature. In the steel plate strengthened by CFRP and aluminum plates, the thermal shear and normal stresses in adhesive layer glued to steel plate become smaller than that in the conventional CFRP bonded specimen. However, the shear stress in adhesive layers between CFRP and aluminum plates in proposed method was higher than the thermal stress in adhesive layers between CFRP plates in conventional method.

DOI： 10.1007/s13296-016-0055-2

Web of Science

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記述言語：日本語   出版者・発行元：公益社団法人 土木学会  

Hammer peening is one of techniques for improving fatigue strength by introducing compressive residual stress at weld toe. Hammer peening by using ICR (impact crack closure retrofit) treatment device, where flat area in front of weld toe is intentionally peened, is also able to introduce compressive residual stress at weld toe as well as near the peened area. In this study, distribution of residual stress introduced in steel plate by peening with ICR device was measured and simulated by finite element analysis considering inelastic and large deformation behavior. In the analysis, strain due to thermal expansion was computed to simulate the peening effect. The analytical showed good agreement with the test results.

DOI： 10.11532/structcivil.62A.685

CiNii Books

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：公益社団法人 土木学会  

DOI： 10.2208/jscejam.72.i_633

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掲載種別：研究論文（国際会議プロシーディングス）  

In this paper, a new peening method in which peening is applied at back surface of the weld toe is proposed. To clarify the effect of peening from back surface of the weld toes on fatigue strength improvement, plate bending fatigue tests under stress ratios R = 0, -1 and –infinity were carried out with out-of-plane gusset specimens. Specimens were composed of steel plates either 12mm or 16mm in thickness. In this study, peening is conducted within either 30mm×80mm or 80mm×30mm (longitudinal direction × transverse direction) rectangular area at back surface of weld toe. As the results of fatigue tests, the specimens composed of12mm thick steel plates on which peening was conducted within the 80mm×30mm rectangular areas showed significant improvement of fatigue strength at stress ratios R = -1, -infinity compared to as-welded condition. The specimens composed of 12mm thick steel plates on which peening was conducted within the 30mm×80mm rectangular areas showed no significant improvement of fatigue strength. Furthermore, the specimens composed of 16mm thick steel plates with peening within the 80mm×30mm rectangular areas showed no significant improvement of fatigue strength.

Scopus

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記述言語：日本語   出版者・発行元：公益社団法人 土木学会  

The one-sided plate bonding method, which can be done in a short time and does not affect traffic flow, has been proposed for repairing the corrosion on the orthotropic steel deck plate. Its effectiveness and the design method of required thickness of patch plates have been studied with the loading tests and FE-analysis. It's known that the fatigue debonding phenomenon might occurs under the repetitive loading, and it is necessary to study about that phenomenon in order to develop the patch plate repair method. In this paper, the debonding of the patcth plate on the orthotropic steel deck plate has been evaluated by the fatigue wheel loading tests and FE-analysis with the real sized specimen and by the fatigue bending tests. As the results, the appropriate edge position of the patch plate on the orthotropic steel deck was proposed.

DOI： 10.11532/structcivil.62A.514

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記述言語：日本語   出版者・発行元：公益社団法人 土木学会  

This study investigated a crack opening-closing behavior by ICR treatment under tensile load and compressive stresses. Out-of-plane gusset specimen in which crack was propagated to boxing weld (<i>N</i>_b crack) or base plate 10mm away from the weld toe (<i>N</i>₁₀ crack) was employed. As the test results, <i>N</i>_b crack completely opened under tensile nominal stress over 40N/mm². In case of <i>N</i>₁₀ crack, a part of crack along the boxing weld opened under tensile nominal stress over 60N/mm². On the other hand, <i>N</i>_b crack completely closed under compressive nominal stress less than 120N/mm². In case of <i>N</i>₁₀ crack, crack along the boxing weld opened partially under compressive nominal stress over 60N/mm<sub>2</sup>.

DOI： 10.11532/structcivil.62A.675

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記述言語：日本語   出版者・発行元：公益社団法人 土木学会  

鋼床版の垂直補剛材上端の溶接部から多数の疲労き裂が報告されている．本研究では，当該溶接部に発生したき裂を対象とした各種補修法の補修効果を板曲げ疲労試験によって比較・検討した．比較する補修法は，グラインダー処理によるき裂の切削法，ICR処理工法，ストップホール法である．疲労試験結果から，グラインダー処理によるき裂の切削法，ICR処理工法では，低応力範囲では疲労き裂の再発生を予防できることがわかった．一方，ストップホールでは，デッキプレート側のストップホール縁をグラインダー処理で仕上げを行わない場合，低応力範囲でもストップホール縁から疲労き裂が再発生することが示された．また，有限要素解析を行い，各種補修法の疲労寿命延命効果を定性的に評価した．

DOI： 10.2208/jscejseee.72.192

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記述言語：日本語   出版者・発行元：公益社団法人 土木学会  

道路橋での鋼床版上面において，橋面舗装のひび割れや舗装と床版界面との付着切れに起因する雨水の浸入や，冬期の凍結防止剤の散布による塩分供給の影響で，デッキプレート上面で腐食減肉が生じることが確認されている．これまで，短時間で施工し交通影響を小さくすることが可能な片面当て板接着補修に着目し，小型試験体を用いた曲げ試験とFEAにより，補修効果について検討してきた． 本研究では，腐食減肉を想定した断面欠損を有する実物大鋼床版試験体を用いて，輪荷重載荷試験（静的・疲労）とFEAにより，輪荷重載荷時の断面欠損の大きさや位置の違いによるデッキプレート近傍の応力の変化と片面当て板接着補修の補修効果を検討した．また，小型試験体検討での力学モデルによる必要板厚設計法が整合することを確認した．

DOI： 10.2208/jscejseee.72.263

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記述言語：日本語   出版者・発行元：公益社団法人 土木学会  

Recently, bonding patch plate repair is focused on as an effective and rapid repair methods applied to the corrosion damaged steel structured. However, the brittle debonding of patch plate is one of the issues of this method. In this study, patch plate repair combined adhesion and stud bolt is proposed to prevent the brittle debonding of patch plate. In order to investigate the effect of proposed method, the tensile tests of steel plate repaired by steel plate with adhesion and stud bolts were carried out. As the result of the tensile tests, specimen with the proposed method prevented the brittle debonding of patch plate, and the debonding strength became higher than that in specimens with conventional bonding method.

DOI： 10.11532/structcivil.62A.639

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：社団法人 日本鋼構造協会  

DOI： 10.11273/jssc.22.85_39

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記述言語：日本語   出版者・発行元：公益社団法人 土木学会  

In steel members bonded with carbon-fiber reinforced polymer (CFRP) plate, the thermal stresses are introduced in the steel members, the CFRP plates and the adhesive layers when temperature changes because the linear thermal expansion coefficients of steel and CFRP are mismatched. In the previous paper, the authors proposed a technique to reduce thermal stress in steel members strengthened by CFRP plate, which involves bonding aluminum alloy plates with CFRP plates. In this research, the thermal stress introduced in the steel plate with CFRP and aluminum plates was measured over one year. As the result, it was shown the thermal stress in steel plate was neglectable small through the all-season. Additionally, a steel plate bonded carbon fiber strand sheets and aluminium plates side by side was tested. In this method, the thermal stress induced in steel plate was also reduced.

DOI： 10.11532/structcivil.61A.808

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記述言語：日本語   出版者・発行元：公益社団法人 土木学会  

It is well known that the fatigue strength of weld toe can be improved by peening which introduces the compressive stress. However, when the compressive over load (OL) is subjected after peening, the compressive stress of welded toe is released and effect of improvement of fatigue strength becomes small. In the previous research, the authors carried out fatigue tests of out-of-plane gusset joint and clarified that the improved fatigue strength is reduced by subjected the compressive OL. In this paper, to evaluate the reduction of improved fatigue strength by the compressive OL, fatigue tests of T-joint were carried out. Furthermore, fatigue strengths of out-of-plane gusset joint and T-joint subjected compression OL after peening were estimated by using the elasto-plastic large deformation analysis and the modified Goodman Diagrams.

DOI： 10.11532/structcivil.61A.638

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記述言語：日本語   出版者・発行元：公益社団法人 土木学会  

経年劣化や設計荷重の変更によって耐荷力が不足した鋼部材に対して，当て板を接着して補強する方法が行われ始めている．さらに，施工事例は少ないが，緊張力を与えた当て板を鋼部材に接着することで鋼部材にプレストレスを導入する方法が一部で用いられている．一方，当て板に緊張力を与えて接着する場合には，緊張力の解放時に接着剤にせん断応力や垂直応力が作用するため，小さな荷重で当て板がはく離してしまう可能性がある．当て板に緊張力を与えて接着する際のはく離荷重を向上するため，当て板端部に非緊張部を設ける方法が提案されている．本研究では，当て板の端部を除く範囲に緊張力を与えられる装置を用いて当て板に部分的に緊張力を与え，プレストレス導入量やはく離荷重を検証した．その結果，当て板端部に非緊張部を設けた場合であっても，当て板接着中央部では当て板全体を緊張したときと同等のプレストレスが導入されることがわかった．また，非緊張部を設けた試験体と当て板全体を緊張した試験体では，非緊張部を設けた方がはく離荷重が大きくなった．さらに，接着剤に生じる主応力を用いてはく離荷重の向上効果を定量的に評価した．

DOI： 10.2208/jscejam.71.I_849

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記述言語：日本語   出版者・発行元：公益社団法人 土木学会  

近年，疲労き裂の簡易な補修法の一つとして，炭素繊維強化樹脂成形板の接着が注目されており，国内外で実鋼構造物に発生した疲労き裂の補修へ試験的に施工されている．炭素繊維強化樹脂成形板の接着によるき裂の進展抑制効果は，応力拡大係数によって評価できる．本研究では，片側の貫通き裂を有する鋼板の全面に両面からCFRP板を接着した場合のき裂進展遅延効果を明らかにするために，引張疲労試験を行った．さらに，CFRP板を接着した場合の応力拡大係数を有限要素解析で評価し，線形破壊力学に基づいて定式化した．最後に，応力拡大係数の理論式を用いてき裂進展解析を行い，疲労試験の結果を評価した．

DOI： 10.2208/jscejam.71.I_795

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記述言語：日本語   出版者・発行元：社団法人 日本鋼構造協会  

Recently, bonding patch plate is used for rehabilitation of steel structures deteriorated with corrosion or fatigue cracks. The patch plate tends to decreases the stress intensity factor at crack tip and delay the crack propagation. However, debonding of patch plates could occur around the end of patch plates and at fatigue crack edges. To evaluate debonding of patch plates bonded to the cracked steel plate, axial loading tests for butted steel joint with bonded patch plates were conducted. Furthermore, the shear and normal stresses in adhesive layer were analyzed. The debonding strength of the joint was evaluated from a view of principal stress in adhesive layer.

DOI： 10.11273/jssc.22.86_1

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記述言語：日本語   出版者・発行元：公益社団法人 土木学会  

This study investigated a steel patch plate bonding technique on one side for the temporary repair of through-thickness crack in orthotropic steel deck, OSD, at vertical stiffener end. Out-of-plane gusset specimen was used in this study. Fatigue tests were carried out using bending type of fatigue test machine under the stress ratio R=-infinity. Steel plate or Cabon Strand Sheets were adhered on the back surface of specimen after through-thickness crack was found. Then bending fatigue test was continued until crack propagated 50mm away from the weld toe on gusset attached surface. By bonding patch plate on the back surface of the specimen, the remaining fatigue life was extremely extended if the patch plate working. Furthermore, when the impact crack closure retrofit, ICR, treatment was applied at the crack on gusset surface with pach plate bonding on the back surface, the remaining fatigue life was also extended.

DOI： 10.11532/structcivil.61A.408

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記述言語：日本語   出版者・発行元：公益社団法人 土木学会  

The impact crack closure retrofit treatment (called ICR treatment) is a technique to delay or arrest fatigue crack growth and enhance residual fatigue life of weld joints including a crack. The treatment is carried out with an air tool to peen plate near the crack and to produce plastic deformation of the steel surface in order to close crack opening. In this study, several fatigue tests on weld joints were conducted under tensile or bending loads in order to verify the life extension effect by ICR treatment. Besides, the effect of the loading types to the life extension was analytically investigated.

DOI： 10.11532/structcivil.61A.627

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：MULTI-SCIENCE PUBL CO LTD  

In steel members strengthened with carbon-fiber reinforced polymer (CFRP) plate, thermal stresses are introduced in the steel members, the CFRP plates and the adhesive layers when temperature changes because the linear thermal expansion coefficients of steel and CFRP are mismatched. Therefore, the thermal stress caused by temperature change has to be considered when designing the repair or strengthening of a steel member with CFRP plates. With this in mind, the authors proposed a technique to reduce thermal stress in steel members strengthened by CFRP plate on both side, which involves bonding aluminum alloy plates with CFRP plates. In this proposed method, the thermal stresses in steel member can be reduced so that there are negligible levels of stress when the cross sectional areas of CFRP and aluminum plates are designed to correspond the coefficient of thermal expansion of steel, even though the thermal stresses are introduced in the CFRP and aluminum plates. So far, a thermal bending moment was not considered in the proposed method, because the steel members strengthened by CFRP-aluminum laminated plate on top and bottom sides were assumed. However, if the proposed method is applied on one side of steel member, the thermal stress in the steel member might not be reduced completely by generated thermal bending moment. Therefore, to confirm the effectiveness of the proposed method for one-sided bonding, heat tests were conducted on a steel plate with a laminated plate bonded on one side. Additionally, to verify test results and calculate the shear and peel stresses in the adhesive layers, a numerical model that used Eigenvalue analysis was proposed and applied. The tests revealed that using the proposed method to create a two-layered laminated plate consisting of CFRP and aluminum plates could not reduce the thermal stress completely in a thin steel plate. However, it was found that the thermal stress in steel plate can be completely reduced, even in thin steel plate, when the proposed method is used to create a three-layered laminated plate consisting of one CFRP plate between two aluminum plates, which when composited has a thermal bending moment equal to zero.

Web of Science

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記述言語：日本語   出版者・発行元：Japanese Society of Steel Construction  

The authors proposed one technique for reduction of stress concentration at stop hole edges which is closing the crack surface between stop holes by using ICR treatment. To evaluate the effectiveness of proposed method, bending fatigue tests of stop hole with ICR treatment were carried out. As the results of bending fatigue tests, fatigue strength of stop hole with ICR treatment was 3 times higher than that without ICR treatment. Additionally, to estimate fatigue strength of stop hole with ICR treatment, estimated equation of stress range of stop hole with ICR treatment was proposed. Fatigue life can be accurately estimated by using the proposed equation.

DOI： 10.11273/jssc.21.53

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

腐食や疲労によって損傷を受けた鋼部材の簡易な補修方法として，当て板を接着して補修する方法が行われ始めている．一方，接着接合では当て板のはく離が懸念されるため，当て板接着補修を用いる際には，あらかじめはく離に対する照査を行う必要がある．はく離のように脆性的な破壊現象を評価する際には，エネルギー解放率が用いられる場合がある．しかし，これまでに提案されている当て板のはく離の評価に用いるエネルギー解放率は，はく離のモードが考慮されていない．本研究では，き裂が生じた鋼板に当て板を接着する場合を対象に，当て板端部およびき裂直上からはく離するときのモード別エネルギー解放率を算出する方法を提案した．モード別のエネルギー解放率は，当て板端部およびき裂直上の位置の接着剤に生じる垂直応力およびせん断応力から算出でき，垂直応力とせん断応力に対して高精度な解を与えることによって，モード別のエネルギー解放率とFEM解析値がほぼ一致した．

DOI： 10.2208/jscejam.70.I_899

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記述言語：日本語   出版者・発行元：Japan Concrete Institute  

コンクリート充填二重鋼管（CFDT）部材は，二重に配置された鋼管の間にコンクリートを充填した構造であり，従来のコンクリート充填（CFT）部材よりも軽量となる利点を有する。一方，CFDT部材の内外鋼管と充填コンクリートが一体となって挙動するためには，両鋼管とコンクリートの界面にずれ止めを設置する必要があると考えられる。本研究では，鋼管にずれ止めを設置したCFDTおよびCFT部材の4点曲げ載荷実験を行った。その結果，内鋼管の径が小さいCFDT部材では，ずれ止めを設置した鋼管とコンクリートとのずれが抑制され，ずれ止めの設置によって最大曲げモーメントが向上した。特に，外鋼管にずれ止めを設置した場合には，最大曲げモーメントの向上率が大きかった。一方，内鋼管の径が小さいCFDT部材では，ずれ止めを設置してもずれの抑制効果が小さく，最大曲げモーメントの向上率も小さかった。

DOI： 10.3151/crt.25.45

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記述言語：日本語  

DOI： 10.2208/jscejam.69.I_595

J-GLOBAL

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記述言語：日本語   出版者・発行元：公益社団法人 土木学会  

The purpose of this study is to propose the simple calculation procedure of stress intensity factor of a cracked steel plate repaired with patch plates. In this paper, firstly, stress intensity factor, SIF, of a cracked steel plate with patch plates was calculated by finite element analysis. The effects of SIF reduction of crack repaired with patch plates were assumed as the reduction of nominal stress and the control of crack opening displacement by patch plate. Then, by applying these effects, the SIF of cracked steel plate with patch plates was estimated by a simple calculation procedure. Finally, it was confirmed that the estimated SIF agrees with that given by FE analysis.

DOI： 10.11532/structcivil.59A.798

J-GLOBAL

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記述言語：日本語   出版者・発行元：公益社団法人 土木学会  

Recently, corrosion damages on upper surface of orthotropic steel deck have been found during the pavement repair work in urban expressway. Thus, a simple repair method for corrosion damages is strongly required to be done during the pavement repair works. Therefore, the authors focused on the bond repair method using patch plates of steel or CFRP. However, in pavement repair, asphalt with temperature of 200&deg;C or more is paved on the upper surface of orthotopic steel deck. Accordingly, adhesive used for bond repair is also exposed to high temperature by asphalt paving. In this study, to clarify the effect of high temperature to the debonding strength of patch plate, steel plates adhesively-repaired with patch plate exposed to high temperature during curing were bending tested. As a result, debonding strength did not decreased by exposing the high temperature during curing of adhesive.

DOI： 10.11532/structcivil.59A.657

J-GLOBAL

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：KOREAN SOC STEEL CONSTRUCTION-KSSC  

Concrete Filled Tubular steel (CFT) member, which represents a superb deformability due to well-known confined effect between steel tube and concrete, has been used mainly as bridge pier. As a progressive composite member, Concrete Filled Double tubular steel (CFDT), which is consist of double skin steel tubes and filled concrete between them, has been proposed. Although a lot of reports on mechanical characteristics of the CFDT member are presently published, the necessity of shear connector for the CFDT member has not been addressed. In this research, the shear connector was installed at the interface between tubes and concrete in the CFDT member. To investigate the effect of the shear connector on the bending characteristics, the four points bending test were carried out. The results show that integrating the steel tubes and concrete enhances its bearing capacity. Furthermore, the strains of outer and inner tubes were also discussed in this paper.

DOI： 10.1007/s13296-013-1005-x

Web of Science

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：KOREAN SOC STEEL CONSTRUCTION-KSSC  

ICR (Impact Crack-closure Retrofit) treatment was developed for extending fatigue life of cracked steel structures by closing the fatigue crack opening. By applying the ICR treatment to as-welded condition, compressive stress remains at weld toe. Therefore, ICR treatment can be used for the improvement of fatigue strength of welded joint at the same level of the other fatigue strength improved techniques. If a compression overload is subjected after ICR treatment, however, the residual compressive stress at weld toe will shift the tensile stress region. Accordingly, improved fatigue strength of welded joints by ICR treatment will be reduced after the compression overloaded. In order to investigate the effect of the compression overload on fatigue strength improved by ICR treatment, fatigue tests of out-of-plane gusset specimens were carried out. As the results, fatigue strength improved by ICR treatment was hardly reduced under the compression overload condition of nominal stress of -190 MPa.

DOI： 10.1007/s13296-013-1016-7

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

In this paper, one technique for reduction of stress concentration at stop hole edges by closing the crack surface between stop holes using ICR treatment was proposed. Tensile and bending test results showed the effectiveness of reduction of stress concentration until opening the closed crack. In tensile test, closed crack opened after nominal stress of 100MPa, while closed crack did not open under nominal stress of 200MPa in bending test. Finite element analysis results also showed that the stress at crack closed by ICR treatment under tensile load was higher than that under bending moment. By closing the crack surface in both sides, the second moment of inertia is recovered about 70% of that without crack. On the other hand, the cross-section area closed by ICR treatment becomes one third of that without crack. Therefore, the nominal stress when the closed crack open under bending moment was higher than that under tensile load. Additionally, it was found that the stresses at closed crack under tensile load and bending moment were higher than that estimated stress by structural mechanics. The reason of this is that the stresses in closed crack area and in ligament areas are not sufficiently distributed. In this research, to estimate the stresses introduced at closed crack under tensile load and bending moment, simple equations considering the bias of stress distribution were also proposed. © 2013 The Society of Materials Science, Japan.

DOI： 10.2472/jsms.62.33

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Japan Society of Civil Engineers  

In the application of multiple Carbon Fiber-Reinforced Plastic (CFRP) plates onto a structural steel member, stepping of the CFRP plate ends is often adopted to prevent debonding. This approach requires the nonuniform extension of CFRP plate lengths. In this study, to shorten the length of CFRP plates, a nonuniform overlapping arrangement of several CFRP plate ends was proposed and the theoretical conditions of arrangement were proposed. Additionally, the design for the stepped-end arrangement of CFRP plates under a uni-axial load was shown. It was confirmed with stress analysis that the stress in the steel plate was reduced to the design value by bonding the CFRP plate with the proposed stepped ends.

DOI： 10.2208/journalofjsce.1.1_22

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2472/jsms.62.33

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記述言語：日本語  

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記述言語：日本語  

DOI： 10.2208/jscejseee.69.26

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記述言語：日本語  

DOI： 10.2208/jscejseee.69.89

J-GLOBAL

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記述言語：日本語   出版者・発行元：Japan Concrete Institute  

本研究では，鉄筋コンクリート床版を有する鋼鈑桁橋を対象に，鉄筋コンクリート壁式防護柵（壁高欄）のひび割れ対策として設けられる伸縮目地（スリット）の数や間隔が主桁の応力に与える影響を明らかにするために，壁高欄にスリットを設けたRC床版鋼合成桁橋のFEM解析を行った。その結果，スリットの間隔が短い場合，スリット位置の外桁下フランジ下面に生じる応力は，壁高欄が設けられていない場合の外桁下フランジの応力とほぼ一致するが，スリットの間隔が長い場合，スリット位置の外桁下フランジの応力は，壁高欄が設けられていない場合よりも大きくなることが示された。

DOI： 10.3151/crt.24.113

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記述言語：日本語  

DOI： 10.2208/jscejam.69.I_701

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記述言語：日本語   出版者・発行元：公益社団法人 土木学会  

Recently, corrosion on top surface of orthotropic steel deck plate has been often found during the bridge pavement repair work in urban expressway. Repair methods for these damages are required to be finished quickly, for example within one or two hours, during the pavement repair work. The authors focused on the steel patch plates bonding repair method with adhesive from the top surface on one side. In this study, cantilever bending tests and FE analysis were carried out and stress behavior of repaired part was discussed. Besides, simple equations for designing of thickness and length of patch plate were proposed.

DOI： 10.11532/structcivil.59A.647

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記述言語：英語  

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記述言語：日本語  

DOI： 10.2208/jscejam.68.I_703

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記述言語：日本語  

DOI： 10.2208/jscejam.68.I_715

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記述言語：日本語  

DOI： 10.11273/jssc.19.76_97

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ASCE-AMER SOC CIVIL ENGINEERS  

This study reported fatigue test results of 300-mm-wide specimens with three details: 80% partial joint penetration (80%PJP), weld melt-through (WMT), and both. The specimens were cut out from full-scale orthotropic deck specimens of 16-mm-thick deck plate. In the fatigue test, the deck plate was subjected to cyclic bending loading and the rib was free from loading. The fatigue fracture surfaces showed that the presence of WMT may affect the initiation of fatigue cracks. A propensity to root cracking rather than toe cracking was observed. Plotting fatigue test results in an S-N diagram showed that the specimens with WMT seemed to have slightly lower fatigue strengths than the 80%PJP specimens, but the difference is more likely to be within a usual scatter of test data, which means that both details have comparable fatigue strength. The present test results satisfied the S-N curves of JSSC-E (80 MPa at 2x10(6) cycles) or AASHTO-C (89 MPa at 2x10(6) cycles). DOI: 10.1061/(ASCE)BE.1943-5592.0000181. (C) 2011 American Society of Civil Engineers.

DOI： 10.1061/(ASCE)BE.1943-5592.0000181

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCI LTD  

In this paper, fatigue tests have been conducted on specimens, which are flat plate with a notch, studwelded plate, T-shaped fillet welded joint and cruciform fillet welded joint, in such a way that fatigue cracks could be initiated and propagated in bending load. Under bending load, surface crack has formed flat semi-ellipse and propagated to about 80% of plate thickness before failure. Besides, the fatigue crack propagation life of cracked welded joint specimen has been predicted using fracture mechanics method. In particular, a correction factor equation has been developed for covering linearly varying stress distribution along crack propagation path under bending load. This equation has been applied to calculating stress intensity factor (SIF) in relation to fatigue life prediction. (C) 2010 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.ijfatigue.2010.12.002

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記述言語：日本語  

DOI： 10.2208/jscejam.67.I_767

J-GLOBAL

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記述言語：日本語  

DOI： 10.11273/jssc.18.70_39

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記述言語：日本語  

DOI： 10.11532/structcivil.57A.1034

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Various types of fatigue cracks have been found in steel bridges. To maintain steel bridges, repair and retrofit methods of such fatigue cracks have been developed. The authors developed a technique which generates plastic deformation of steel surface near the crack in order to close crack opening by an impact air tool. This method is called Impact Crack Closure Retrofit treatment (ICR treatment). Plate bending fatigue tests of out-of-plane gusset specimens were carried out. Fatigue cracks at turn-around welds and those which have propagated 10 and 20 mm were ICR-treated. Fatigue test results showed significant improvement in the fatigue life of specimens due to ICR treatment.

DOI： 10.2208/jsceseee.28.21s

Scopus

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記述言語：日本語  

DOI： 10.2208/jscejam.67.I_777

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記述言語：日本語  

DOI： 10.2208/jscejseee.67.336

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記述言語：日本語  

DOI： 10.2208/jscejseee.67.351

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記述言語：日本語  

DOI： 10.11532/structcivil.57A.852

J-GLOBAL

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記述言語：日本語   出版者・発行元：JAPAN WELDING SOCIETY  

DOI： 10.2207/jjws.79.328

CiNii Books

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その他リンク： https://jlc.jst.go.jp/DN/JALC/00353063790?from=CiNii

記述言語：日本語   出版者・発行元：公益社団法人 土木学会  

切断位置を跨いでCFRP板が接着された鋼板では，CFRP板の剛性を大きくすると，切断縁の接着剤に生じるはく離せん断応力を小さくできるが，CFRP板の付着端のはく離せん断応力が大きくなる．したがって，CFRP板接着切断鋼板では，はく離せん断応力を小さくするために，切断縁でCFRP板の剛性を大きく，CFRP板の付着端で剛性を小さくするのが良い．CFRP板の端部に段差を設けた場合，切断縁で剛性が大きく，付着端で剛性が小さくなるため，はく離せん断応力が小さくなり，CFRP板のはく離荷重の上昇が期待できる．本研究では，端部に段差を設けて2枚のCFRP板が切断鋼板に接着された場合に対して，切断縁およびCFRP板の付着端の接着剤に生じるはく離せん断応力を最小にする各CFRP板の剛性を明らかにする．

DOI： 10.2208/jsceja.66.717

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記述言語：英語  

DOI： 10.11532/structcivil.56A.77

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記述言語：英語  

DOI： 10.2208/jsceja.66.264

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記述言語：日本語  

DOI： 10.2208/jsceja.66.264

J-GLOBAL

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記述言語：日本語  

DOI： 10.2208/jsceja.66.368

J-GLOBAL

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記述言語：日本語  

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DOI： 10.2208/jsceja.66.368

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記述言語：日本語  

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記述言語：日本語  

DOI： 10.11273/jssc.17.65_43

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2472/jsms.58.937

Scopus

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

Steel and concrete composite deck, which is arranged channel shape steel members in the transverse direction on the top surface of the bottom steel plate, has been investigated by the authors. By the arrangement of channel shape steel members welded to the bottom steel plate, the steel and concrete composite deck with cellars in the concrete becomes to be more lightweight than typical types of steel and concrete composite decks. For highway bridge decks, it is very important to verify the fatigue strength of the welded joint In this paper, fatigue tests of the welded joint between the channel shape steel and the bottom steel plate were carried out under the tensile fatigue stress. ©2009 The Society of Materials Sdence,.

DOI： 10.2472/jsms.58.937

Scopus

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記述言語：日本語   出版者・発行元：一般社団法人 日本接着学会  

DOI： 10.11618/adhesion.45.139

CiNii Books

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その他リンク： https://jlc.jst.go.jp/DN/JALC/00329520838?from=CiNii

記述言語：日本語   出版者・発行元：土木学会  

CiNii Books

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記述言語：日本語   出版者・発行元：Japan Society of Civil Engineers  

複数のCFRP板を鋼板に重ねて接着する場合，CFRP板の端部に段差を設けると，CFRP板が鋼板からはく離するときの荷重，すなわち，はく離荷重が上昇することが知られている．しかし，はく離荷重を最大にする条件は未だ明らかにされていない．そこで本研究では，複数のCFRP板が接着された場合に対する基礎的な研究として，2枚のCFRP板が鋼板に接着された場合，すなわち一つの段差が設けられた場合に対して，はく離荷重を最大にするCFRP板の剛性比および段差長を理論解析によって明らかにする．

DOI： 10.2208/jsceja.65.362

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記述言語：日本語   出版者・発行元：社団法人 日本鋼構造協会  

Fatigue evaluation of trough rib to deck weld joint failed in weld throat is presented. S-N curve of the joint is determined in term of stress range in weld throat by carrying out plate bending fatigue tests and collecting previous test data. Two approaches are proposed for calculating stress range in weld throat in actual bridge with orthotropic steel deck based on one or two points of measured stress. Both methods give approximate fatigue lives, suggesting one point of stress measurement is also possible in practice. By stress measurement at an actual bridge with orthotropic steel deck, stress range in summer tends to be higher and thus more damaging than in winter.

DOI： 10.11273/jssc.16.64_11

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記述言語：英語   出版者・発行元：Japan Society of Civil Engineers  

複数のCFRP板を鋼板に重ねて接着する場合，CFRP板の端部に段差を設けると，CFRP板が鋼板からはく離するときの荷重，すなわち，はく離荷重が上昇することが知られている．しかし，はく離荷重を最大にする条件は未だ明らかにされていない．そこで本研究では，複数のCFRP板が接着された場合に対する基礎的な研究として，2枚のCFRP板が鋼板に接着された場合，すなわち一つの段差が設けられた場合に対して，はく離荷重を最大にするCFRP板の剛性比および段差長を理論解析によって明らかにする．

DOI： 10.2208/jsceja.65.362

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記述言語：英語   出版者・発行元：公益社団法人 土木学会  

Fatigue tests have been carried out on three types of non load-carrying fillet welded joint subjected plate bending, such as single-side fillet welded joint, T-shaped fillet welded joint and cruciform fillet welded joint. Fatigue failure mode of each type of welded joint has been demonstrated. The test results show that fatigue crack forms flat semi-ellipse during crack propagation and propagates to about 80% of plate thickness before failure. The fatigue strength and life recorded under bending test have been assessed and compared with the previous test results. Moreover, the fatigue strength for bending is evaluated by using one-millimeter stress method.

DOI： 10.11532/structcivil.55A.871

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記述言語：日本語   出版者・発行元：公益社団法人 土木学会  

Since stud shear connectors are used for the connection of an aluminum deck to a steel girder, composite effects are produced between both. In this study, statically loading tests of composite girders consisting of an aluminum deck and a steel girder clarifies their yield and maximum loads as well as their behavior of collapse. Applicability of the incomplete composite theory to the composite effects of an aluminum deck with a steel girder is verified by the elastic behavior of the test girders.

DOI： 10.11532/structcivil.55A.1172

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記述言語：日本語  

DOI： 10.2208/jsceja.65.961

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：KOREAN SOC STEEL CONSTRUCTION-KSSC  

Fatigue tests have been carried out on three types of non load-carrying fillet welded joint subjected plate bending, such as single-side fillet welded joint, T-shaped fillet welded joint and cruciform fillet welded joint. Fatigue failure of each welded joint has been demonstrated. The test results show that fatigue crack forms flat semi-ellipse during crack propagation and propagates to about 80% of plate thickness before failure. The fatigue strength and life recorded under bending test have been examined and compared with the previous results obtained by tension test. The fatigue strength of the fillet welded joint under bending is higher than that of the welded joint under tension.

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記述言語：日本語  

DOI： 10.11532/structcivil.54A.842

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記述言語：日本語  

DOI： 10.2208/journalam.11.903

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記述言語：日本語  

DOI： 10.2208/jsceja.64.789

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記述言語：英語  

DOI： 10.2208/jsceja.64.789

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記述言語：日本語   出版者・発行元：土木学会  

DOI： 10.2208/journalam.10.963

CiNii Books

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記述言語：日本語   出版者・発行元：日本コンクリート工学協会  

本研究では,Robinson床版に代表される従来の銅・コンクリート合成床版と比較して軽量化した鋼・コンクリート合成床版の実用化に向けての初期段階として,軽量をもたらすために配置されるみぞ形鋼の付着せん断強度の把握を目的とした押抜きせん断実験を行った。得られた結果より,みぞ形鋼の付着せん断強度は,ずれ止めとして十分な付着せん断強度を有していること,およびみぞ形鋼のウェブ厚さと高さの比に影響を受けることを明らかにした。さらに,みぞ形鋼の簡易付着せん断強度推定式を提案した。

CiNii Books

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その他リンク： http://dl.ndl.go.jp/info:ndljp/pid/10641073

記述言語：日本語  

DOI： 10.2208/jsceja.63.655

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記述言語：英語  

DOI： 10.2208/jsceja.63.655

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記述言語：日本語  

DOI： 10.11532/structcivil.53A.1313

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記述言語：日本語   出版者・発行元：日本コンクリート工学協会  

鋼・コンクリート合成床版の軽量化を目的に,底鋼板に溶接された溝形鋼内を中空とした合成部材のせん断耐力について基礎的実験を行った。本構造では,従来型の鋼・コンクリート合成床版に比べて単位面積あたりの質量を10～15%程度軽減できる。本研究では,はり試験体を用いた橋軸方向および橋軸直角方向のせん断耐力について,せん断スパン比の影響を考慮して検討した結果,既往のせん断耐力算定式によって評価できることが分かった。

CiNii Books

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その他リンク： http://dl.ndl.go.jp/info:ndljp/pid/10641072

記述言語：日本語  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：TECHNO-PRESS  

In steel bridges fatigue cracks are sometimes repaired by placing drilled holes at the crack tips. From the meaning that the drilled holes stop the propagation of cracks, they are called stop-holes. Since stop-holes are regarded as an emergency measure to delay crack propagation, usually some substantial repair follows. However, if the stress at the stop-holes is below their fatigue limit, fatigue cracks would not be expected to occur. The purpose of this study is to present the conditions under which stop-holes prevent the re-initiation of fatigue cracks. The fatigue limit of stop-holes and the equations necessary to estimate the maximum stress on the circumference of the stop-holes are provided.

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記述言語：日本語  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2472/jsms.47.1233

Scopus

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記述言語：日本語   出版者・発行元：土木学会 ; 2007-  

CiNii Books

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記述言語：日本語  

J-GLOBAL

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記述言語：日本語  

J-GLOBAL

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記述言語：英語   出版者・発行元：CRC PRESS-TAYLOR & FRANCIS GROUP  

© 2016 Taylor &amp; Francis Group, London. In Japan, many fatigue cracks from weld root between orthotropic steel deck and trough rib have been found. So far, there is no effective method to improve fatigue strength preventing weld root crack between orthotropic steel deck and trough rib as an after-construction procedure. One reason for this is because the location of fatigue crack initiation tends to be inside the closed trough rib. In this study, the authors propose one technic to improve the fatigue strength of the weld root between orthotropic steel decks and trough ribs from outside the closed rib. The technique is conducted with peening in front of the weld toe outside the trough rib. The residual compressive stress will be introduced at the weld root at inside the trough rib by the peening from outside the closed rib. The fatigue strength improvement of weld root between orthotropic steel decks and trough ribs by the peening from outside the closed rib was revealed by the bending fatigue tests.

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記述言語：日本語   出版者・発行元：一般社団法人 溶接学会  

本研究では、材料の繰返し弾塑性挙動を反映した疲労寿命の予測技術を採用することにより、Uリブへのピーニング処理技術および疲労き裂発生寿命にに関する数値解析を実施するとともに、供試体を対象とした実験結果との比較を通じてその精度を検証した。

DOI： 10.14920/jwstaikai.2016f.0_358

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記述言語：日本語   出版者・発行元：一般社団法人 溶接学会  

本研究では，ピーニング処理技術に関連するメカニズムの明確化とそれを基にした最適化手法の確立を目的として，メカニカルな打撃を採用するピーニング処理に関する基礎的な実験を行うとともに，同条件を模擬した弾塑性FEシミュレーションを実施し計測結果と比較することにより，繰返し圧縮に伴う形状変化や実測が困難な局所的な残留応力分布，さらに材料特性の変化などに関して考察を行う．

J-GLOBAL

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記述言語：日本語   出版者・発行元：土木学会  

Shear deformation of CFRP affects how the force transfers from a steel plate to a CFRP plate in a CFRP bonded steel plate under an axial force. A widely accepted shear lag theory to model a CFRP bonded steel plate does not usually consider the effect of shear deformation in the CFRP plate. This study proposes a way to account for the effect of shear deformation in the CFRP plate on the force transfer between steel and CFRP by increasing the thickness of adhesive layer in the conventional shear lag theory.

DOI： 10.11532/structcivil.61A.798

CiNii Books

J-GLOBAL

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記述言語：日本語   出版者・発行元：関西大学理工学会  

CiNii Books

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その他リンク： http://hdl.handle.net/10112/9481

記述言語：日本語   出版者・発行元：日本鋼構造協会  

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記述言語：日本語  

J-GLOBAL

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記述言語：日本語  

J-GLOBAL

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記述言語：日本語   出版者・発行元：日本鋼構造協会  

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記述言語：日本語  

CiNii Books

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記述言語：日本語   出版者・発行元：軽金属溶接構造協会  

CiNii Books

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記述言語：日本語  

CiNii Books

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記述言語：英語  

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記述言語：英語  

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出願番号：2009-263101 

公開番号：2011-106181 

特許番号/登録番号：5441114 

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出願番号：2009-291750 

特許番号/登録番号：4895407 

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特許番号/登録番号：4780594 

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出願番号：2004-20535 

公開番号：2005-213826 

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受賞国：日本国

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受賞国：日本国

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受賞国：日本国

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受賞国：日本国

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受賞国：日本国

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受賞国：日本国

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受賞国：日本国

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受賞国：日本国

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受賞国：日本国

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受賞国：日本国

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受賞国：日本国

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受賞国：日本国

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受賞国：日本国

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受賞国：日本国

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受賞国：日本国

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受賞国：日本国

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受賞国：日本国

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受賞国：日本国

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受賞国：日本国

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受賞国：日本国

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受賞国：日本国

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