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OKUI Yoshiaki
| Environmental Science and Civil Engineering Division | Professor |
| Department of Civil and Environmental Engineering | Dean |
Researcher information
■ Degree■ Research Keyword
■ Field Of Study
- Social infrastructure (civil Engineering, architecture, disaster prevention), Structural and seismic engineering
- Jun. 2025, Research Achievement Award, Japan Society of Civil Engineers
- Sep. 2018, Kurita‐Albrecht Best Scientific Paper Award – Steel at 12th Japan German Bridge Symposium, Seismic response of isolated bridge with high damping rubber bearings: Self-heating effect at subzero temperatures
Okui, Y;Nakamura, K;Sato, T;Imai, T
45399286;45281821 - May 2011, 田中賞：論文部門
- May 2010, 土木学会論文賞
- May 2010, 田中賞：論文部門
- Jun. 2006, Tanaka Award in the Papers Division, DEVELOPMENT OF WEB SLENDERNESS LIMITS FOR COMPOSITE I-GIRDERS ACCOUNTING FOR INITIAL BENDING MOMENT
Performance information
■ Paper- A STUDY ON RATIONALIZATION OF BRIDGE STEEL EXPANSION JOINT
Masami MATSUNO; Taro TONEGAWA; Yoshiaki OKUI
Japanese Journal of JSCE, Volume：79, Number：11, First page：n/a, Last page：n/a, Nov. 2023, [Reviewed]
Japan Society of Civil Engineers, Japanese, Scientific journal
DOI：https://doi.org/10.2208/jscejj.22-00332
DOI ID：10.2208/jscejj.22-00332, eISSN：2436-6021 - System redundancy of steel I‐girder bridges and proposal of a system factor for load rating
Yoshiaki Okui; Makoto Denda; Kazuki Kumaki; Satoshi Sakuma
ce/papers, Volume：6, Number：3-4, First page：964, Last page：969, Sep. 2023, [Reviewed], [Lead, Corresponding]
Abstract
3D nonlinear FE analyses of existing plate‐girder bridges were carried out to investigate system redundancy. A comparison of the ultimate live load factors between a whole bridge system (WBS) model and a single girder (SG) model shows that WBS's ultimate live load factor is larger than SG's factor. This difference in the ultimate load factors is interpreted as the system redundancy effect. A system factor to quantify the system redundancy has been proposed based on the nonlinear FE analysis results. The proposed system factor is defined as a factor to convert the ultimate live load factor and rating factor for load rating based on linear analysis into those based on nonlinear analysis. A case study to calculate the system factor for three existing bridges shows dependency of the system factor on the number of girders, composite/non‐composite girders, simple span/continuous span.
Wiley, Scientific journal
DOI：https://doi.org/10.1002/cepa.2276
DOI ID：10.1002/cepa.2276, ISSN：2509-7075, eISSN：2509-7075 - LOAD-CARRYING CAPACITY AND CRACK WIDTH CONTROL FOR LIMIT STATE DESIGN METHOD OF COMPOSITE BRIDGES
Yoshiaki OKUI
Japanese Journal of JSCE, Volume：79, Number：14, First page：n/a, Last page：n/a, May 2023, [Reviewed], [Lead, Corresponding]
Japan Society of Civil Engineers, Japanese, Scientific journal
DOI：https://doi.org/10.2208/jscejj.22-14001
DOI ID：10.2208/jscejj.22-14001, eISSN：2436-6021 - 既設橋評価のための実態交通荷重を考慮した活荷重係数に関する研究
Toru Kasamatsu; Yoshiaki Okui; Masashi Kimura; Ryota Kano; Satoru Sakuma; Hideo Tokida
構造工学論文集, Volume：69A, First page：58, Last page：68, Apr. 2023, [Reviewed]
Japanese - A proposal for evaluation method of system redundancy and system factors in load rating of steel bridges
奥井 義昭, 傳田 諒, 熊木 和輝, 佐久間 智
構造工学論文集 Ａ, Volume：68A, First page：1, Last page：10, Mar. 2022, [Reviewed], [Invited], [Lead]
Japanese, Scientific journal - A STUDY ON LOAD-CARRYING CAPACITY EVALUATION OF EXISTING BRIDGES USING LOAD RATING
Toru KASAMATSU; Yoshiaki OKUI; Masahiro ISHIBASHI; Hajime YAMAKAWA
Journal of Japan Society of Civil Engineers, Ser. A1 (Structural Engineering & Earthquake Engineering (SE/EE)), Volume：77, Number：3, First page：418, Last page：426, Nov. 2021, [Reviewed]
Japan Society of Civil Engineers, Japanese, Scientific journal
DOI：https://doi.org/10.2208/jscejseee.77.3_418
DOI ID：10.2208/jscejseee.77.3_418, eISSN：2185-4653 - 鋼橋の強靱化・長寿命化に向けた研究の取組み
舘石 和雄,奥井 義昭,村越 潤,穴見 健吾,岩崎 英治
橋梁と基礎, Volume：55, Number：2, First page：16, Last page：21, 2021 - 鋼道路橋のLoad Ratingの検討
奥井 義昭,宮下 剛
橋梁と基礎, Volume：55, Number：2, First page：23, Last page：26, 2021 - 鋼橋の設計・評価技術の高度化, JSSC Topics 委員会活動とその成果
奥井義昭
Journal of Steel Structures & Construction, Volume：No.46, First page：41, Last page：42, 2021 - Probabilistic Compressive Strength of Stiffened Steel Plates Exhibiting Column-Like Behavior: Ultimate and Serviceability Limit States
Mahmudur Rahman; Yoshiaki Okui; Masato Komuro; Muhammad Atif Anwer; Azusa Numata
Journal of Structural Engineering, Volume：146, Number：9, First page：04020166, Last page：1-04020166-15, Sep. 2020, [Reviewed]
American Society of Civil Engineers (ASCE), Scientific journal
DOI：https://doi.org/10.1061/(asce)st.1943-541x.0002719
DOI ID：10.1061/(asce)st.1943-541x.0002719, ISSN：0733-9445, eISSN：1943-541X - Flexural Capacity Accounting for SBHS500 Steel of Composite Bridge Girders
Dang Viet Duc; Yoshiaki Okui
Lecture Notes in Civil Engineering, Volume：54, First page：209, Last page：214, 2020
Springer, English, In book
DOI：https://doi.org/10.1007/978-981-15-0802-8_30
DOI ID：10.1007/978-981-15-0802-8_30, ISSN：2366-2565, SCOPUS ID：85073688541 - THE LIMIT STATES COMPRESSIVE STRENGTH ESTIMATION FOR SIMPLE STIFFENED PLATE WITH LARGE ASPECT RATIO
MIYAZAKI Yasuhiro; RAHMAN Mahmudur; OKUI Yoshiaki
Journal of Japan Society of Civil Engineers, Ser. A1 (Structural Engineering & Earthquake Engineering (SE/EE)), Volume：76, Number：1, First page：67, Last page：81, Jan. 2020, [Reviewed]The compressive strengths of stiffened plates with a single longitudinal stiffener were examined from experimental and numerical results. First, totally four compressive loading tests of rectangular short columns consisting of four stiffened plates were carried out for two different slenderness parameters and two steel grades, namely ordinary steel SM490Y and bridge high-performance steel SBHS500. During the loading test, compressive load and longitudinal displacement as well as out-of-plane displacements were monitored. The adequacy of a nonlinear finite element model was verified using the test results, and it was confirmed that the developed analysis model reproduced the compressive behavior with sufficient accuracy. Finally, both mean and standard deviation of the ultimate as well as serviceability limit strengths are reported in comparison with road bridge specifications, such as AASHTO, Canadian Code and Eurocode.
Japan Society of Civil Engineers, Japanese, Scientific journal
DOI：https://doi.org/10.2208/jscejseee.76.1_67
DOI ID：10.2208/jscejseee.76.1_67, CiNii Articles ID：130007787666 - Seismic response of isolated bridge with high damping rubber bearings: Self-heating effect at subzero temperatures
Yoshiaki Okui; Keisuke Nakamura; Takashi Sato; Takashi Imai
Steel Construction,, Volume：12, Number：1, First page：2, Last page：9, Jan. 2019, [Reviewed], [Invited]
English, Scientific journal - SM570を使用したコンクリート充填鋼製橋脚の 地震時変形性能に関する実験的研究
神田信也,松原拓朗,田嶋仁志,奥井義昭,志治謙一,岡田誠司
構造工学論文集, Volume：64A, First page：222, Last page：230, Mar. 2018, [Reviewed]
Japanese, Scientific journal - Reliability Based Design for Buckling Strength of Stiffened Steel Plates: Ultimate and Serviceability Limit States
Rahman, M. and Okui, Y.
Proc. of 11th ADB-JSP Research Forum, Tokyo, Japan, 2018 - 次の橋梁設計基準が目指すべきもの
奥井義昭
宮地技報, Volume：31, First page：1, Last page：3, 2018 - Probabilistic column-like buckling strength for stiffened steel plates under uniaxial compression
Rahman, M., Okui, Y. and Komuro, M.
Proc. of JSCE 20th Int'l Summer Symposium, Hokkaido, Japan, First page：3, Last page：4, 2018 - An Experimental Study on Seismic Performance of Concrete-Filled Steel Piers
Shinya Kanda; Takuro Matsubara; Hitoshi Tajima; Yoshiaki Okui; Kenichi Shiji; Seiji Okada
Proc. of 40th IABSE Symposium, First page：S23-125, Last page：S23-132, 2018, [Reviewed]
English, International conference proceedings - Probabilistic strength at serviceability limit state for normal and SBHS slender stiffened plates under uniaxial compression
Mahmudur Rahman; Yoshiaki Okui; Muhammad Atif Anwer
International Journal of Steel Structures, Volume：18, Number：4, First page：1397, Last page：1409, 2018, [Reviewed]
English, Scientific journal - Probabilistic ultimate buckling strength of stiffened plates, considering thick and high-performance steel
Mahmudur Rahman; Yoshiaki Okui; Takahiro Shoji; Masato Komuro
JOURNAL OF CONSTRUCTIONAL STEEL RESEARCH, Volume：138, First page：184, Last page：195, Nov. 2017, [Reviewed]
English, Scientific journal
DOI：https://doi.org/10.1016/j.jcsr.2017.07.004
DOI ID：10.1016/j.jcsr.2017.07.004, ISSN：0143-974X, eISSN：1873-5983, Web of Science ID：WOS:000418213100013 - TEMPERATURE DEPENDENCE OF MECHANICAL BEHAVIOR OF HIGH DAMPING RUBBER BEARINGS CONSIDERING SELF HEATING
Yoshiaki OKUI; Yasuhiro ONOUE; Takashi SATO; Takashi IMAI
木学会論文集A1（構造・地震工学）, Volume：73, Number：1, First page：165, Last page：173, Feb. 2017, [Reviewed]
Scientific journal - An improved rheology model for the description of the rate-dependent cyclic behavior of high damping rubber bearings
D. A. Nguyen; J. Dang; Y. Okui; A. F. M. S. Amin; S. Okada; T. Imai
SOIL DYNAMICS AND EARTHQUAKE ENGINEERING, Volume：77, First page：416, Last page：431, Oct. 2015, [Reviewed]
English, Scientific journal
DOI：https://doi.org/10.1016/j.soildyn.2015.06.001
DOI ID：10.1016/j.soildyn.2015.06.001, ISSN：0267-7261, eISSN：1879-341X, Web of Science ID：WOS:000360420000039 - Nonlinear Viscosity Law in Finite-Element Analysis of High Damping Rubber Bearings and Expansion Joints
A. F. M. S. Amin; A. R. Bhuiyan; T. Hossain; Y. Okui
JOURNAL OF ENGINEERING MECHANICS, Volume：141, Number：6, First page：04014169, Last page：1-11, Jun. 2015, [Reviewed]
English, Scientific journal
DOI：https://doi.org/10.1061/(ASCE)EM.1943-7889.0000888
DOI ID：10.1061/(ASCE)EM.1943-7889.0000888, ISSN：0733-9399, eISSN：1943-7889, Web of Science ID：WOS:000354551500009 - Ultimate strength curves of compressive member with box sections in real steel bridges
Nogami Kuniei; Takeuchi Yukiharu; Yamashita Youhei; Kishi Yusuke; Nagai Masatsugu; Okui Yoshiaki; Nozaka Katsuyoshi; komuro Masato; Miyashita Takeshi
Kozo Kogaku Ronbunshu. A (Journal of Structural Engineering. A), Volume：61, First page：35, Last page：48, Mar. 2015, [Reviewed]
This paper describes the discussions on the ultimate strength characteristics for existing compression members of steel truss and arch bridges, and proposes new ultimate strength curve of welded box-section members. The investigation objects are section size, material, initial imperfections, stiffener size of compression member which designed based on Spec. for Highway Bridges 2002. In addition, ultimate strength characteristics of existing compression members with box-section are calculated for several steel types. The results of investigations shows that the 0.2σy is able to apply as upper limit of compression residual stress (σrc) for HTSS members. The results of numerical analyses provide the ultimate strength characteristics of welded box-section compression members for steel truss and arch bridges. Moreover, new ultimate strength curve is proposed for the compression members in this research.
Japan Society of Civil Engineers, Japanese
DOI：https://doi.org/10.11532/structcivil.61A.35
DOI ID：10.11532/structcivil.61A.35, ISSN：1881-6614, CiNii Articles ID：130005439094, CiNii Books ID：AA12210243 - 既設構造物の性能評価 −臨床構造工学−
奥井義昭
土木学会誌, Volume：Vol.100, No.10, First page：16, Last page：17, 2015 - 鋼多主桁橋の非線形リダンダンシー解析
見原理一; 加藤 修; 岩崎英治; 奥井義昭
Volume：17, Number：1, First page：77, Last page：88, Aug. 2014
Japanese, International conference proceedings - リダンダンシー評価ガイドラインと今後の展望
吉岡 勉; 奥井義昭; 岩崎英治
Volume：17, Number：1, First page：97, Last page：104, Aug. 2014
Japanese, International conference proceedings - Numerical study on ultimate strength of compressive flange considering statistical data for distributions of initial displacement and residual stress
Komuro Masato; Okui Yoshiaki; Nozaka Katsuyoshi; Miyashita Takeshi; Nogami Kuniei; Nagai Masatsugu
Kozo Kogaku Ronbunshu. A (Journal of Structural Engineering. A), Volume：60, First page：80, Last page：93, Mar. 2014, [Reviewed]
The ultimate strengths of compressive steel plates simply supported on three sides and one side free (outstanding plates) were numerically investigated by means of combining FE elasto-plastic analysis and Monte Carlo simulation considering the statistical data for variability of the initial displacement and residual stress. From this study, the following results were obtained: (1) a standard deviation of the ultimate strength tends to increase in the region of the with-thickness ratio parameter R ≅ 1.0; (2) in the region of R < 0.7, the effect of the residual stress on the ultimate strength is very small; and (3) considering the statistical data for variability of the initial displacement and residual stress of the plate, a rational design formula can be proposed.
Japan Society of Civil Engineers, Japanese
DOI：https://doi.org/10.11532/structcivil.60A.80
DOI ID：10.11532/structcivil.60A.80, ISSN：1881-6614, CiNii Articles ID：130005439004 - Probabilistic distributions of plate buckling strength for normal and bridge high-performance steels
Dang Viet Duc; Yoshiaki Okui; Koichi Hagiwara; Masatsugu Nagai
INTERNATIONAL JOURNAL OF STEEL STRUCTURES, Volume：13, Number：3, First page：557, Last page：567, Sep. 2013, [Reviewed]
English, Scientific journal
DOI：https://doi.org/10.1007/s13296-013-3014-1
DOI ID：10.1007/s13296-013-3014-1, ISSN：1598-2351, eISSN：2093-6311, Web of Science ID：WOS:000325702000014 - Experimental study on the strength of SBHS I-girder
Nozaka Katsuyoshi; Okui Yoshiaki; Komuro Masato; Miyashita Takeshi; Nogami Kuniei; Nagai Masatsugu
Kozo Kogaku Ronbunshu. A (Journal of Structural Engineering. A), Volume：59, First page：70, Last page：79, Mar. 2013, [Reviewed]
Recently, High Performance Steel, HPS, especially for bridge construction has been developed, named SBHS. Although SBHS has high strength and high weldability, SBHS steel has not been widely adopted in bridge constructions in Japan, because SBHS steel has not been specified in the Specifications for Highway Bridges in Japan. In this research, bending and shear strength of SBHS I-girder were experimentally investigated, and test results indicated that SBHS I-giders can be designed safely using concepts adopted in current specifications. In addition, residual stress distriutions in SBHS I-girder were measured to confirm no negative impact exist against the strength.
Japan Society of Civil Engineers, Japanese
DOI：https://doi.org/10.11532/structcivil.59A.70
DOI ID：10.11532/structcivil.59A.70, CiNii Articles ID：130005438822 - Mechanical behavior of high damping rubber bearings at low temperatures
Dung Anh NGUYEN, Yoshiaki OKUI, Md. Shafquat HASAN, Hiroshi MITAMURA, Takashi IMAI
Proc. of International Symposium on New Technologies for Urban Safety of Mega Cities in Asia, Volume：Paper id 2-150, First page：1, Last page：8, 2013 - Low temperature behavior and modeling of high damping rubber bearings
Tomoya MATSUMOTO, Yoshiaki OKUI, Dung Anh NGUYEN, Md. Shafquat HASAN, Kaho TAKAHASHI, Hiroshi MITAMURA, Takashi IMAI
Proc. of International Symposium on New Technologies for Urban Safety of Mega Cities in Asia, Volume：Paper id 4-067, First page：1, Last page：8, 2013 - 限界状態設計法と維持管理
奥井義昭
片山技報, Volume：33, First page：2, Last page：7, 2013 - プレキャスト床版連続合成桁のずれ止めに関する実験および解析
大城 壮司, 上條 崇, 奥井 義昭, 長井 正嗣
土木学会論文集A1（構造・地震工学）, Volume：68, Number：2, First page：331, Last page：346, 2012, [Reviewed]
Scientific journal - Application of Rheology Modeling to Natural Rubber and Lead Rubber Bearings: A Simplified Model and Low Temperature Behavior
Muhammad Kashif RAZZAQ, Yoshiaki OKUI, Abdur Rahman BHUIYAN, A. F. M. Saiful AMIN, Hiroshi MITAMURA, Takashi IMAI
Journal of Japan Society of Civil Engineers, Ser. A1 (Structural Engineering & Earthquake Engineering (SE/EE)), Volume：68, Number：3, First page：526, Last page：541, 2012, [Reviewed]
Scientific journal - Design, construction and maintenance of steel and steel-concrete hybrid bridges in Japan
Nagai, M., Okui, Y., Miyashita, T.,
Festschrift Gerhard Hanswille, Institut f:ur Konstruktven Ingenieurbau, Bergische Universit:at Wuppertal, Volume：Heft 20, First page：293, Last page：302, 2011 - Bending Moment Capacity and Combined Strength under Bending Moment and Shear for Composite Girders
Duc, D.V. Okui, Y., Nagai, M., Inaba, N. Homma, A.
Proc. of the 6th International Symposium on Steel Structures, First page：941, Last page：947, 2011, [Reviewed] - Experimental study on cracking behavior of pre-cast concrete slab in continuous composite girders under negative bending moment
Takeshi Oshiro; Takashi Kamijo; Yoshiaki Okui; Masatsugu Nagai
構造工学論文集A, Volume：56A, First page：1027, Last page：1040, Mar. 2010, [Reviewed]
土木学会, Scientific journal - 2重合成I桁の曲げ及びせん断強度の評価方法に関する実験的研究
稲葉尚文、奥井義昭、長井正嗣、本間淳史、春日井俊博、野呂直以
土木学会論文集A, Volume：66, Number：1, First page：117, Last page：132, 2010, [Reviewed]
土木学会, Scientific journal - Experimental Study of Rate-Dependent Mechanical Behavior of Laminated Rubber Bearings
T.Imai, A.R.Bhuiyan, M.K.Razzaq, Y.Okui, H.Mitamura
Joint Conf. Proc. of 7th Int. Conf. on Urban Earthquake Eng. & 5th Int. Conf. on Earthquake Eng., First page：1921, Last page：1928, 2010
7th CUEE and 5th ICEE Joint Conference - 合成I桁の曲げ，せん断相関強度解明に関する実験的研究
稲葉尚文,奥井義昭,長井正嗣,本間淳史,春日井俊博,野呂直以
土木学会論文集Ａ, Volume：66, Number：2, First page：393, Last page：405, 2010, [Reviewed]
土木学会, Scientific journal - A rheology model of high damping rubber bearings for seismic analysis: Identification of nonlinear viscosity
A. R. Bhuiyan; Y. Okui; H. Mitamura; T. Imai
INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES, Volume：46, Number：7-8, First page：1778, Last page：1792, Apr. 2009, [Reviewed]
English, Scientific journal
DOI：https://doi.org/10.1016/j.ijsolstr.2009.01.005
DOI ID：10.1016/j.ijsolstr.2009.01.005, ISSN：0020-7683, CiNii Articles ID：120001371436, Web of Science ID：WOS:000264573700019 - ハイブリッド桁の限界状態設計法試案
長井正嗣、押下里治、奥井義昭他
JSSCテクニカルレポート, Number：83, 2009
日本鋼構造協会 - Effect of Rubber Bearing's Modeling on Seismic Response of Base Isolated Highway Bridge
M.K.Razzaq, A.R.Bhuiyan, Y.Okui, H.Mitamura, and T.Imai
Joint Conf. Proc. of 7th Int. Conf. on Urban Earthquake Eng. & 5th Int. Conf. on Earthquake Eng., First page：1855, Last page：1862, 2009
7th CUEE and 5th ICEE Joint Conference - Ultimate flexure and shear strength of I-girder under hogging bending moment in double-composite girder bridges
Masatsugu Nagai; Naofumi Inaba; Yoshiaki Okui
STEEL CONCRETE COMPOSITE AND HYBRID STRUCTURES, First page：195, Last page：200, 2009, [Reviewed]
English, International conference proceedings
Web of Science ID：WOS:000273559400020 - 低塔を有する200ｍ合成斜張橋の弾塑性挙動と終局強度
井尾伸太郎; 野上邦栄; 奥井義昭; 森園康之
複合・合成構造の活用に関するシンポジウム論文報告, Volume：8, First page：41-1-41-6, Last page：1-41-6, 2009
土木学会 - 我国の鋼トラス橋を対象としたリダンダンシー解析の検討
永谷; 秀樹 . 明石; 直光 . 松田; 岳憲 . 安田; 昌宏 . 石井; 博典 . 宮森; 雅之 . 小幡; 泰弘 . 平山; 奥井義昭; 義
土木学会論文集Ａ, Volume：65, Number：2, First page：410, Last page：425, 2009, [Reviewed], [Last]
鋼トラス橋梁を対象としてリダンダンシー（構造冗長性）評価の検討を行った．ここでリダンダンシーとは，橋梁の1部材もしくは一部が破断した場合における，橋梁全体系の余耐力を意味する．ケーススタディとして実際に斜材の破断が生じた木曽川大橋（単純下路トラス1960年設計）と，3径間連続上路トラス（1980年設計）を取り上げた．線形解析に基づくリダンダンシー評価を検討の基本としたが，別に行った橋梁全体の非線形解析結果と比較することで，線形リダンダンシー解析の妥当性を検証した．さらに格点部のみを詳細にモデル化した弾塑性解析を実施し，リダンダンシー解析における格点部の影響を検討した．最後に今回行ったリダンダンシー解析の結果を受けて，合理的な維持管理への提言をまとめた．The structural redundancy for steel truss bridges is investigated through the case studies for a simply supported steel truss bridge constructed in 1960 and a three-span continuous steel truss bridge designed as a standard model bridge in 1980. Here, the structural redundancy means the capability of a bridge to continue to carry loads after the failure of a member or a part of the bridge. To evaluate the redundancy, the linear structural analysis is employed as a standard procedure. The applicability of linear analysis to redundancy evaluation is examined by comparing with the nonlinear analysis results. In addition, detailed nonlinear FE analysis for a joint of truss bridge is carried out to check effect of a joint failure on the redundancy. Finally, on the basis of the study results, some recommendations toward rational bridge maintenance are presented.
土木学会, Japanese, Scientific journal
DOI：https://doi.org/10.2208/jsceja.65.410
DOI ID：10.2208/jsceja.65.410, ISSN：1880-6023, CiNii Articles ID：120001794167 - 合成I桁の正，負曲げ及び相関強度評価に関する一考察
長井正嗣; 稲葉尚文; 奥井義昭; 宮下剛; 平山繁幸; 細見直史
構造工学論文集, Volume：55A, First page：115, Last page：123, 2009, [Reviewed]
Benefit from LSD introduction is apparent for the design of steel-concrete composite girder bridges. In order to establish LSD, one of issues is to get a correct evaluation of ultimate strength in plastic region. So far, such evaluating formulae have been presented mainly from EC and AASHTO LRED. However, unresolved subjects to be improved or clarified have been seen, hence, several of them were clarified in this study based on experiment. Composite test girders were subjected to sagging or hogging flexure. Ultimate flexure strength of the girder under sagging flexure, in which plastic neutral axis is positioned in the slab, was examined. Ultimate coupled flexure/shear strength was also examined. Finally, the design procedure related to this study was summarized.
Japan Society of Civil Engineers, Scientific journal
DOI：https://doi.org/10.11532/structcivil.55A.115
DOI ID：10.11532/structcivil.55A.115, ISSN：1881-820X, CiNii Articles ID：130004950397 - 連続合成桁の負曲げ領域における横倒れ座屈設計法
奥井義昭; Bandula Heva, T; M; 小室雅人; 山口栄輝; 長井正嗣
構造工学論文集, Volume：54A, First page：58, Last page：67, 2008, [Reviewed]
In the current design procedure for recent continuous composite steel-concrete bridges at an internal support under negative bending moment, the lateral torsional buckling theory is applied to evaluate an allowable stress in disregard of lateral restraint of top flange by a concrete slab. In actual continuous composite bridges, instead of the lateral torsional buckling, restrained distortional buckling may occur. This paper proposes a design procedure for the restrained distortional buckling of continuous composite girders under negative bending moment.
土木学会, Japanese, Scientific journal
DOI：https://doi.org/10.11532/structcivil.54A.58
DOI ID：10.11532/structcivil.54A.58, ISSN：1881-6614, CiNii Articles ID：120004470172, CiNii Books ID：AA12210243 - Numerical simulation of the excavation damaged zone around an opening in brittle rock
A. Golshani; M. Oda; Y. Okui; T. Takemura; E. Munkhtogo
INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES, Volume：44, Number：6, First page：835, Last page：845, Sep. 2007, [Reviewed]
English, Scientific journal
DOI：https://doi.org/10.1016/j.ijrmms.2006.12.005
DOI ID：10.1016/j.ijrmms.2006.12.005, ISSN：1365-1609, Web of Science ID：WOS:000247163900003 - Effect of concrete crushing on flexural strength of steel-concrete composite girders
Vivek Kumar Gupta; Yoshiaki Okui; Naofumi Inaba; Masatsugu Nagai
Structural Engineering/Earthquake Engineering, Volume：24, Number：2, 2007, [Reviewed]
English, Scientific journal
DOI：https://doi.org/10.2208/jsceseee.24.73s
DOI ID：10.2208/jsceseee.24.73s, ISSN：0289-8063, SCOPUS ID：36849048675 - Time-dependent damage growth and failure mechanism around tunnel under deep geological environments
Takemura, T; Golshani, A; Oda, M; Okui, Y; Takahashi, M
11th World Congress of the International society for rock mechanics, 2007
English, Research society - 二重合成桁橋における水平スタッ ドのせん断耐力に関する実験的研究
碇山晴久; 長井正嗣; 奥井義昭; 宮下 剛; 岩崎英治; 平山繁幸; 石川健一
第7回複合構造の活用に関するシンポジウム論文集, First page：20-1-20-8, Last page：1-20-8, 2007 - Effect of concrete crushing on flexural strength of steel-concrete composite girders
Vivek Kumar Gupta; Yoshiaki Okui; Naofumi Inaba; Masatsugu Nagai
Doboku Gakkai Ronbunshuu A, Volume：63, Number：3, First page：475, Last page：485, 2007, [Reviewed]
土木学会, English, Scientific journal
DOI：https://doi.org/10.2208/jsceja.63.475
DOI ID：10.2208/jsceja.63.475, ISSN：1880-6023, CiNii Articles ID：80018159276, SCOPUS ID：79954449338 - Block FEM for time-dependent shear-lag behavior in two I-girder composite bridges
Yoshiaki Okui; Masatsugu Nagai
JOURNAL OF BRIDGE ENGINEERING, Volume：12, Number：1, First page：72, Last page：79, Jan. 2007, [Reviewed], [Lead]
English, Scientific journal
DOI：https://doi.org/10.1061/(ASCE)1084-0702(2007)12:1(72)
DOI ID：10.1061/(ASCE)1084-0702(2007)12:1(72), ISSN：1084-0702, CiNii Articles ID：80018677281, Web of Science ID：WOS:000245204900009 - A micromechanical model for brittle failure of rock and its relation to crack growth observed in triaxial compression tests of granite
A Golshani; Y Okui; M Oda; T Takemura
MECHANICS OF MATERIALS, Volume：38, Number：4, First page：287, Last page：303, Apr. 2006, [Reviewed]
English, Scientific journal
DOI：https://doi.org/10.1016/j.mechmat.2005.07.003
DOI ID：10.1016/j.mechmat.2005.07.003, ISSN：0167-6636, CiNii Articles ID：80017668158, Web of Science ID：WOS:000234949800002 - Development of web slenderness limits for composite I-girders accounting for initial bending moment
Vivek Kumar Gupta; Yoshiaki Okui; Masatsugu Nagai
Structural Engineering/Earthquake Engineering, Volume：23, Number：2, 2006, [Reviewed]
English, Scientific journal
DOI：https://doi.org/10.2208/jsceseee.23.229s
DOI ID：10.2208/jsceseee.23.229s, ISSN：0289-8063, SCOPUS ID：33847325387 - A micromechanical approach in modeling time- and stress-dependent failure of brittle rocks
Golshani, A; Okui, Y; Oda, M; Takemura, T
Mechanics of Materials, Volume：38, First page：287-303, 2006, [Reviewed]
English, Scientific journal - 連続合成桁のひび割れとケミカルプレストレスに関する実験的検討
木村 充; 長井正嗣; 細見雅生; 奥井義昭
構造工学論文集, Volume：52A, First page：039-1046, Last page：1046, 2006, [Reviewed]
土木学会, Scientific journal - Hyperelasticity model for finite element analysis of natural and high damping rubbers in compression and shear
AFMS Amin; SI Wiraguna; AR Bhuiyan; Y Okui
JOURNAL OF ENGINEERING MECHANICS-ASCE, Volume：132, Number：1, First page：54, Last page：64, Jan. 2006, [Reviewed]
English, Scientific journal
DOI：https://doi.org/10.1061/(ASCE)0733-9399(2006)132:1(54)
DOI ID：10.1061/(ASCE)0733-9399(2006)132:1(54), ISSN：0733-9399, CiNii Articles ID：80017686150, Web of Science ID：WOS:000234377700006 - Development of web slenderness limits for composite i-girders accounting for initial bending moment
Vivek Kumar Gupta; Yoshiaki Okui; Masatsugu Nagai
Doboku Gakkai Ronbunshuu A, Volume：62, Number：4, First page：854, Last page：864, 2006, [Reviewed]
English, Scientific journal
DOI：https://doi.org/10.2208/jsceja.62.854
DOI ID：10.2208/jsceja.62.854, ISSN：1880-6023, SCOPUS ID：36849073991 - Nonlinear dependence of viscosity in modeling the rate-dependent response of natural and high damping rubbers in compression and shear: Experimental identification and numerical verification
AFMS Amin; A Lion; S Sekita; Y Okui
INTERNATIONAL JOURNAL OF PLASTICITY, Volume：22, Number：9, First page：1610, Last page：1657, 2006, [Reviewed]
English, Scientific journal
DOI：https://doi.org/10.1016/j.ijplas.2005.09.005
DOI ID：10.1016/j.ijplas.2005.09.005, ISSN：0749-6419, CiNii Articles ID：120001370476, Web of Science ID：WOS:000238583700003 - Some topics of studies for steel-concrete composite girders
Okui Y. and Gupta V.K.
Proc. of 8th Korea-China-Japan Symposium on steel structure, Seoul, 2005 - Analytical study on steel-concrete composite girders
Okui Y.,
Proc. of Japan-Bangladesh Joint Seminar on Advances in Bridge Engineering, Dhaka, Bangladesh, First page：113, Last page：124, 2005 - Hydraulic behaviour of Inada granite in the excavation disturbed zone around underground openings
Golshani, A., Okui, Y., Oda, M., Takemura, T.
Proceedings of the Seventh International Summer Symposium, JSCE, Tokyo, First page：153, Last page：156, 2005 - Proceedings of the Japan-Bangladesh Joint SEminar on Advances in Bridges Eng.
Amin, A.F.M.S, Okui, Y., Safiullah, A.M.M editors
The instituton of Engineers, Bangladsh, First page：168, 2005 - Load-carrying capacity of composite girders in cable-stayed bridges
Okui Y., Nagai M., Iwasaki E. and Hirono T.
4th European conference on steel and composite structures, Eurosteel 2005, Maastricht, Netherlands, First page：4.6.7, Last page：12, 2005 - 連続合成桁のひび割れ幅算定のための床版有効幅推定式の提案
奥井義昭; 本田卓士; セントラルコンサルタンツ; Khan, Q; niversity of Engineering; Technology Taxila; 長井正嗣; 長岡技術科
土木学会論文集, Volume：I-70780, Number：780, First page：155, Last page：163, 2005, [Reviewed]
An effective width formula for crack width evaluation in negative bending moment regions near internal supports of continuous composite girder bridges is proposed. The formula takes account of shear-lag effect and includes cracking effect in concrete slabs of composite bridges. A parametric study of 3D nonlinear FE analyses for composite bridges with span lengths ranging from 30 to 60 m are carried out to develop the formula. Since the effective width varies depending on the strain level of concrete slabs due to nonlinear effects, a modification equation of the effective width is proposed as well.
Japan Society of Civil Engineers, Japanese, Scientific journal
DOI：https://doi.org/10.2208/jscej.2005.780_155
DOI ID：10.2208/jscej.2005.780_155, ISSN：0289-7806, CiNii Articles ID：10013712696, CiNii Books ID：AN10014020 - 合成桁の終局曲げ強度特性に関する研究
稲葉 尚文; 奥井 義昭; 長井 正嗣
第26回日本道路会議論文集, First page：14026, 2005 - Time dependent continuous damage model for brittle failure of rocks
Golshani, A; Okui, Y; Takemura, T; Oda, M
Proceedings of the International society for rock mechanics Regional symposium EUROCK 2004 & 53th Geomechanics Colloquy,, First page：701-706, Last page：706, 2004, [Reviewed]
English, Research society - High Damping Rubber for Base Isolation Bearing: Mechanical Behavior and Constitutive Modeling
Amin; A.F.M.S; Bangladesh University of Engineering; Technology; Okui, Y
Filler Reinforcement of Rubbr, First page：51, Last page：57, 2004 - 連続合成桁の初期ひび割れ状態を考慮したひび割れ幅, 鉄筋応力算定法の一提案
長井正嗣; 長岡技術科; 奥井義昭; 岩崎英治
土木学会論文集, Volume：I-67759, Number：759, First page：283, Last page：292, 2004, [Reviewed]
In recent years, methods of evaluating the crack width in concrete slabs and those of the stress in reinforcing bars at intermediate supports in continuous composite bridges have been proposed. They are applicable to evaluation of the crack width and stress in reinforcing bars at the stabilized crack state (fully cracked state). In many actual bridges, however, the initial crack state has been observed under the hogging bending moment. In this paper, employing formulas recommended in a current method and CEB/FIP-90, a method of evaluating the crack width and stress in reinforcing bars is proposed, in which the crack width and stress in reinforcing bars for both initial and stabilized crack states can be dealt with.
Japan Society of Civil Engineers, Japanese, Scientific journal
DOI：https://doi.org/10.2208/jscej.2004.759_283
DOI ID：10.2208/jscej.2004.759_283, ISSN：0289-7806, CiNii Articles ID：10012033501, CiNii Books ID：AN10014020 - 湾岸地域における複合構造橋梁の実用化に関する調査研究
依田,奥井
JSSCテクニカルレポ-ト58, First page：1, Last page：227, 2004
(社)日本鋼構造協会 - 高架橋の動的非線形解析における感度分析と部分構造モデルの妥当性の検討
奥井義昭
構造工学論文集, Volume：50A, First page：1419, Last page：1426, 2004, [Reviewed]
土木学会, Scientific journal - 合成斜張橋主桁の終局挙動の解明と安定照査法
長井正嗣; 長岡技術科; 奥井義昭; 野上邦栄; 東京都立大; 廣野智紀
構造工学論文集, Volume：50A, First page：53, Last page：59, 2004, [Reviewed]
土木学会, Scientific journal - Fragility analysis of a bridge substructure under Level-1 earthquake and its application to determination of safety factors
Hoque, M; Seshimo, Y; Tokyo Electric power Service; Tunekuni, M; Okui, Y; Sugiyama; Yamanashi University), T
J. Struct. Eng., JSCE, Volume：50A, First page：257, Last page：268, 2004
Scientific journal - Measurement of lateral deformation in natural and high damping rubbers in large deformation uniaxial tests
AFMS Amin; MS Alam; Y Okui
JOURNAL OF TESTING AND EVALUATION, Volume：31, Number：6, First page：524, Last page：532, Nov. 2003, [Reviewed]
English, Scientific journal
ISSN：0090-3973, Web of Science ID：WOS:000186516200010 - Micromechanics-based prediction of creep failure of hard rock for long-term safety of high-level radioactive waste disposal system
K Miura; Y Okui; H Horii
MECHANICS OF MATERIALS, Volume：35, Number：3-6, First page：587, Last page：601, Mar. 2003, [Reviewed]
English, Scientific journal
ISSN：0167-6636, Web of Science ID：WOS:000180597600028 - A method for crack width evaluation of continuous composite girder bridges accounting for shear-lag effect
Qaiser-Uz-Zaman Khan; Takuji Honda; Yoshiaki Okui; Masatsugu Nagai
Structural Engineering/Earthquake Engineering, Volume：20, Number：2, 2003, [Reviewed]
Japan Society of Civil Engineers, English, Scientific journal
DOI：https://doi.org/10.2208/jsceseee.20.131s
DOI ID：10.2208/jsceseee.20.131s, ISSN：0289-8063, SCOPUS ID：1842430095 - A microcrack-based constitutive model for brittle geomaterials
A Golshani; Y Okui; T Takemura; M Oda; K Suzuki
ROCK STRESS, First page：219, Last page：224, 2003, [Reviewed]
English, International conference proceedings
Web of Science ID：WOS:000189130200024 - COMPARATIVE STUDY ON CRACK WIDTH EVALUATION METHODS FOR CONTINUOUS COMPOSITE GIRDERS
NAGAI Masatsugu; OKUI Yoshiaki; IWASAKI Eiji
Doboku Gakkai Ronbunshu, Volume：710, First page：427, Last page：437, Jul. 2002, [Reviewed]
Recent design codes for continuous composite girder bridges allow tensile cracking in a concrete slab near intermediate supports. To ensure durability of the concrete slab, introduced crack width has to be limited within an allowable limit, and accordingly it becomes important to predict crack width under a service load. In this paper, crack width evaluation methods for steel-concrete composite girder under negative bending moment are compared to investigate differences in those mechanical background and evaluated results. Inconsistency in application of conventional methods is pointed out.
Japan Society of Civil Engineers, Japanese
DOI：https://doi.org/10.2208/jscej.2002.710_427
DOI ID：10.2208/jscej.2002.710_427, ISSN：0289-7806, CiNii Articles ID：10009264847, CiNii Books ID：AN10014020 - An improved hyperelasticity relation in modeling viscoelasticity response of natural and high damping rubbers in compression: experiments, parameter identification and numerical verification
AFMS Amin; MS Alam; Y Okui
MECHANICS OF MATERIALS, Volume：34, Number：2, First page：75, Last page：95, Feb. 2002, [Reviewed], [Last]
English, Scientific journal
DOI：https://doi.org/10.1016/S0167-6636(01)00102-8
DOI ID：10.1016/S0167-6636(01)00102-8, ISSN：0167-6636, CiNii Articles ID：80012870216, Web of Science ID：WOS:000174202300001 - EX-plication of micromechanics to modeling compressive failure of rock
Y Okui; H Horii
MATERIALS SCIENCE RESEARCH INTERNATIONAL, Volume：6, Number：2, First page：65, Last page：73, Jun. 2000
English, Scientific journal
DOI：https://doi.org/10.2472/jsms.49.6Appendix_65
DOI ID：10.2472/jsms.49.6Appendix_65, ISSN：1341-1683, Web of Science ID：WOS:000175672100001 - 鋼橋技術研究会設計部会報告書
奥井他,33名
First page：2015, 2000 - Mechanism of microcracking localization of compressive rocks: Anisotropic interaction between microcracks
Y Okui; H Horii
LOCALIZATION AND BIFURCATION THEORY FOR SOILS AND ROCKS, First page：143, Last page：151, 1998, [Reviewed]
English, International conference proceedings
Web of Science ID：WOS:000078033200016 - 合成箱桁を主桁とする斜張橋の力学特性と適用スパンに関する研究
構造工学論文集, Volume：44A, First page：1171, Last page：1179, 1998, [Reviewed]
土木学会, Scientific journal - Stress and time-dependent failure of brittle rocks under compression: A theoretical prediction
Y Okui; H Horii
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH, Volume：102, Number：B7, First page：14869, Last page：14881, Jul. 1997, [Reviewed]
English, Scientific journal
ISSN：2169-9313, eISSN：2169-9356, Web of Science ID：WOS:A1997XJ83100010 - Stress and Time-Dependent Failure of Brittle Rocks under Compression:a Theoretical Predection
OKUI Y; HORII H
Journal of Geophysical Research, Volume：102, Number：B7, First page：14869, Last page：14881, 1997, [Reviewed], [Lead]
Scientific journal
DOI：https://doi.org/10.1029/97JB00476
DOI ID：10.1029/97JB00476, ISSN：0148-0227, CiNii Articles ID：30013336745 - MICROMECHANICS-BASED CONTINUUM THEORY AND NUMERICAL-ANALYSIS OF LOCALIZATION PHENOMENA
H HORII; Y OKUI
COMPUTER METHODS AND ADVANCES IN GEOMECHANICS, VOL 2, First page：1687, Last page：1692, 1994, [Reviewed]
English, International conference proceedings
Web of Science ID：WOS:A1994BB12T00128 - A CONTINUUM THEORY FOR SOLIDS CONTAINING MICRODEFECTS
Y OKUI; H HORII; N AKIYAMA
INTERNATIONAL JOURNAL OF ENGINEERING SCIENCE, Volume：31, Number：5, First page：735, Last page：749, May 1993, [Reviewed], [Lead]
English, Scientific journal
DOI：https://doi.org/10.1016/0020-7225(93)90121-A
DOI ID：10.1016/0020-7225(93)90121-A, ISSN：0020-7225, CiNii Articles ID：80006991839, Web of Science ID：WOS:A1993KW58100004 - A MICROMECHANICS-BASED CONTINUUM THEORY FOR STRAIN LOCALIZATION AND SOFTENING UNDER COMPRESSION
Y OKUI; H HORII; N AKIYAMA
FRACTURE MECHANICS OF CONCRETE STRUCTURES /, First page：275, Last page：280, 1992, [Reviewed]
English, International conference proceedings
Web of Science ID：WOS:A1992BX45N00029 - Evaluation of bending moment due to geometrical nonlinearity in main girder of cable-stayed bridges.
NAGAI Masatugu; AKAO Hiroshi; SANO Shin-ichiro; OKUI Yoshiaki
Doboku Gakkai Ronbunshu, Volume：1988, Number：392, First page：307, Last page：316, 1988, [Reviewed], [Last]
Bending moment due to geometrical nonlinearity in a main girder should be checked on designing cable-stayed girder bridges. Even though the employment of nonlinear analysis by an electronic computer is powerful, much time is also inevitable for carrying it out.
In this paper, a formula to estimate the bending moment due to nonlinearity is proposed and also dominant parameters which have a close relation to nonlinear behavior of the girder are summarized. This simple formula is useful for designers' judgement whether nonlinear effect should be taken into account or not beforehand. In addition, it is available for selecting a bending rigidity of the girder of long-spanned cable-stayed girder bridges at preliminary design stage.
Japan Society of Civil Engineers, Japanese
DOI：https://doi.org/10.2208/jscej.1988.392_307
DOI ID：10.2208/jscej.1988.392_307, ISSN：0289-7806, CiNii Articles ID：130003799573, CiNii Books ID：AN10014020
- 横倒れ座屈した鋼桁のCFRPによる補強効果に関する実験研究
平岩アキ; 平田桐也; 大垣賀津雄; SAKHIR Syll Amadou; 秀熊佑哉; 櫻井俊太; 宮下剛; 奥井義昭
Volume：79th, 2024
J-Global ID：202402241074496028 - 鋼橋の設計・評価技術の高度化
鋼橋の強靱化・長寿命化研究委員会,合理化設計研究部会 奥井他
（一社）日本鋼構造協会，テクニカルレポート, Volume：No.114, Number：114, 2018
J-Global ID：201902272562961863 - Next Step Direction of Steel Bridge Design
奥井義昭
橋梁と基礎, Volume：49, Number：8, First page：44, Last page：47, Aug. 2015
Japanese
ISSN：0287-170X, CiNii Articles ID：40020547106, CiNii Books ID：AN00062923 - 免震橋の水平2方向耐震性能に関する漸増動的解析
党紀; 蛯沢佑紀; 五十嵐晃; 奥井義昭
Volume：69, Number：I-058, First page：115, Last page：116, 10 Sep. 2014
大阪大学，9/10-12
Japanese, Summary national conference - Probabilistic local buckling strength analysis of compressive platesfor normal and bridge high performance steels
Y. Okui; M. Komuro; D. DUC Vlet
37th IABSE Symposium Madrid 2014, Volume：102, First page：1157, Last page：1163, Sep. 2014, [Reviewed]
International Association for Bridge and Structural Engineering, English
DOI：https://doi.org/10.2749/222137814814067392
DOI ID：10.2749/222137814814067392 - Recent topics of Japanese design codes for steel and composite bridges
Okui, Y
First page：9, Last page：14, 2009 - Development of Rheology model for RBs and LRBs and its implementation in seismic analysis
Razzaq, M.K; Bhuiyan, A.R; Okui, Y; Mitamura, H; Imai,T
First page：21, Last page：24, 2009 - Elasto-plastic behavior and ultimate strength of 200-meters cable-stayed composite girder bridge with low tower
Shintarou Io; Kuniei Nogami; Yoshiaki Okui; Yasuyuki Morizono
2009 - A case study for after fracture redundancy analysis of a turss bridge in Japan
Yoshiaki Okui; Hideki Nagatani; Naomitsu Akashi; Takenori Matsuda; Masahiro Yasuda; Hironori Ishii; Masayuki Miyamori; Yasuhiro Obata; Hiroshi Hirayama
First page：87, Last page：92, 2009 - Recent topics of Japanese design codes for steel and composite bridges
Okui, Y
Proceedings of the 10th Korea-China-Japan Symposium on Structural Steel Construction, First page：9, Last page：14, 2009 - Development of Rheology model for RBs and LRBs and its implementation in seismic analysis
Razzaq, M.K; Bhuiyan, A.R; Okui, Y; Mitamura, H; Imai,T
Proc. of 11th International summer symposium conference organized by Japan Society of Civil Engineers, First page：21, Last page：24, 2009 - Elasto-plastic behavior and ultimate strength of 200-meters cable-stayed composite girder bridge with low tower
Shintarou Io; Kuniei Nogami; Yoshiaki Okui; Yasuyuki Morizono
Proc. of the 10th Japan-Korea joint Symposium on steel bridges, Volume：10, 2009 - A case study for after fracture redundancy analysis of a turss bridge in Japan
Yoshiaki Okui; Hideki Nagatani; Naomitsu Akashi; Takenori Matsuda; Masahiro Yasuda; Hironori Ishii; Masayuki Miyamori; Yasuhiro Obata; Hiroshi Hirayama
Proc. of Australia-Japan workshop on steel and composite structures, First page：87, Last page：92, 2009 - Revisit of section classification requirements for composite girders under positive flexure
Okui, Y; Gupta, V.K; Nagai, M
Volume：A, First page：381, Last page：386, 2008 - A design method of continuous composite girders under negative bending moment against restrained distortional buckling
Okui, Y; Bandula Heva T.M; Komuro, M; Nagai, M
First page：1, Last page：7, 2008 - Nonlinear viscosity law for rate-dependent response of high damping rubber: FE implementation and verification
A. R. Bhuiyan; A. Em. S. Amin; T. Hossain; Y. Okui
CONSTITUTIVE MODELS FOR RUBBER V, First page：279, Last page：+, 2008
English
Web of Science ID：WOS:000251796000042 - Revisit of section classification requirements for composite girders under positive flexure
Okui, Y; Gupta, V.K; Nagai, M
Eurosteel 2008: 5th European Conference on Steel and Composite Structures, Ofner, R., Beg, D., Dink, J., Greiner, R., Unterweger H., (eds.), Volume：A, First page：381, Last page：386, 2008
ECCS European Convention for Construction Steelwork - A design method of continuous composite girders under negative bending moment against restrained distortional buckling
Okui, Y; Bandula Heva T.M; Komuro, M; Nagai, M
Eleventh East Asia-Pacific Conference on Structural Engineering & Construction (EASEC-11) "Building a sustainable environment", First page：1, Last page：7, 2008 - 連続合成桁中間支点部の横座屈に対する合理的な設計方法の開発とその検証
奥井 義昭
総合研究機構研究プロジェクト研究成果報告書, Number：5(18年度), First page：626, Last page：627, 2007
埼玉大学総合研究機構 - Web Slenderness Limit for Section Classification of Unshored Composite Girders
Okui, Y; Gupta, V.K; Nagai, M
2007 - Experimental study on ultimate strength of composite and double-composite girders
Nagai, M; Inaba, N; Tomita, Y; Okui, Y
Volume：2, First page：329, Last page：334, 2007 - Experimental Study on Shear Strength of Lying Stud in Double-Composite Girder Bridges
Nagai, M; Okui, Y; Miyashita, T; Iwasaki, E; Ikariyama H; Kenichi ISHIKAWA; Shigeyuki HIRAYAMA
2007 - Design issues for steel-concrete composite girders
Okui, Y
First page：85, Last page：93, 2007 - 連続合成桁中間支点部の横座屈に対する合理的な設計方法の開発とその検証
奥井 義昭
総合研究機構研究プロジェクト研究成果報告書, Number：5(18年度), First page：626, Last page：627, 2007 - Web Slenderness Limit for Section Classification of Unshored Composite Girders
Okui, Y; Gupta, V.K; Nagai, M
Proc. of The 7th German-Japanese Bridge Symposium, 2007 - Nonlinear viscosity law for rate-dependent response of high damping rubber: EF implementation and verification
Bhuiyan, A.R; Amin, A; Hossan, T; Okui, Y
Proc. of the 5th European Conference on Constitutive Models for Rubber, ECCMR, First page：279, Last page：284, 2007 - Experimental study on ultimate strength of composite and double-composite girders
Nagai, M; Inaba, N; Tomita, Y; Okui, Y
Proc. of 8th Pacific Structural Steel Conference, Volume：2, First page：329, Last page：334, 2007 - Experimental Study on Shear Strength of Lying Stud in Double-Composite Girder Bridges
Nagai, M; Okui, Y; Miyashita, T; Iwasaki, E; Ikariyama H; Kenichi ISHIKAWA; Shigeyuki HIRAYAMA
Proc. of The 7th German-Japanese Bridge Symposium, 2007 - Design issues for steel-concrete composite girders
Okui, Y
Proc. of China-Japan Joint Seminar on Steel and Composite Bridges, First page：85, Last page：93, 2007 - Numerical simulation of an excavation disturbed zonearound a tunnel in brittle rock<速報>
小田 匡寛奥井
Volume：39, First page：110, Last page：113, 2006
The micromechanics-based damage model proposed by Golshani et al. (2005) is extended so that time-dependent behavior of brittle material can be taken into account, with special attention to the numerical analysis of an excavation damage zone (EDZ) around a tunnel, which is a major concern in assessing the safety of underground repositories. The present model is capable of reproducing the three characteristic stages of creep behavior (i.e., primary, secondary and tertiary creep) commonly observed in laboratory creep tests. Using the present model, sub-critical microcrack growth parameters (i.e. n and A) can be determined for Inada granite by fitting the numerical results of elapse time to failure versus the creep stress ratio curve with the experimental data under both dry and wet conditions. It is found that moisture has a significant influence on the parameter A rather than the parameter n. Use of the extended model makes it possible to analyze not only the extension of microcrack length, but also the development of the excavation damage zone (EDZ) around tunnels as a function of time. The disturbed zones mainly develop in the sidewalls of the tunnel in the case that the vertical stress is larger than the horizontal stress.
English
ISSN：1880-4446, CiNii Articles ID：120001370434 - 勝鬨橋の再跳開技術に関する調査研究報告書
藤野陽三,奥井義昭
2006
土木学会 - 合成桁による設計思想の転換
奥井義昭
Volume：40, First page：64, Last page：67, 2006 - 高減衰ゴムのマイクロメカニクスに基づく構成則モデルと破壊予測手法の開発
奥井 義昭
総合研究機構研究プロジェクト研究成果報告書, Number：4(17年度), 2006
埼玉大学総合研究機構 - 鋼連続合成桁橋の構造合理化に関する技術検討業務報告書
長井正嗣,奥井義昭
2006
（財）高速道路技術センター - 鋼合成構造標準示方書の説明
奥井義昭
第11回鋼構造基礎講座「合成構造の設計と事例紹介」テキスト, 2006
土木学会 - 硬岩の長期劣化予測を目的とした微視情報も算出可能な連続体理論の構築とその検証
奥井義昭,小田匡寛
科学研究補助金研究成果報告書, 2006 - Ultimate Strength of Composite I-Girder in Pure Positive Bending
Nagai, M; Okui, Y; Inaba, N
First page：ID-030-1-10, 2006 - FE Analysis with Smeared Crack Model for Crack Width Evaluation in Continuous Composite Girders
Okui, Y; Honda, Y; Khan, Q.Z; Nagai M
First page：ID-034-1-7, 2006 - Effect of Initial Bending Moment in Composite Girder under Flexure for Unshored Construction
Gupta, V.K; Okui, Y; Nagai, M
First page：ID-047-1-8, 2006 - Numerical simulation of an excavation disturbed zonearound a tunnel in brittle rock<速報>
小田 匡寛奥井
埼玉大学紀要, 工学部, 第1部論文集, Volume：39, First page：110, Last page：113, 2006
The micromechanics-based damage model proposed by Golshani et al. (2005) is extended so that time-dependent behavior of brittle material can be taken into account, with special attention to the numerical analysis of an excavation damage zone (EDZ) around a tunnel, which is a major concern in assessing the safety of underground repositories. The present model is capable of reproducing the three characteristic stages of creep behavior (i.e., primary, secondary and tertiary creep) commonly observed in laboratory creep tests. Using the present model, sub-critical microcrack growth parameters (i.e. n and A) can be determined for Inada granite by fitting the numerical results of elapse time to failure versus the creep stress ratio curve with the experimental data under both dry and wet conditions. It is found that moisture has a significant influence on the parameter A rather than the parameter n. Use of the extended model makes it possible to analyze not only the extension of microcrack length, but also the development of the excavation damage zone (EDZ) around tunnels as a function of time. The disturbed zones mainly develop in the sidewalls of the tunnel in the case that the vertical stress is larger than the horizontal stress.
埼玉大学工学部, English
ISSN：1880-4446, CiNii Articles ID：120001370434 - 勝鬨橋の再跳開技術に関する調査研究報告書
藤野陽三; 奥井義昭
2006 - 合成桁による設計思想の転換
奥井義昭
橋梁と基礎, Volume：40, Number：8, First page：64, Last page：67, 2006
建設図書, Japanese
ISSN：0287-170X, CiNii Articles ID：40007444667, CiNii Books ID：AN00062923 - 高減衰ゴムのマイクロメカニクスに基づく構成則モデルと破壊予測手法の開発
奥井 義昭
総合研究機構研究プロジェクト研究成果報告書, Number：4(17年度), 2006 - 鋼連続合成桁橋の構造合理化に関する技術検討業務報告書
長井正嗣; 奥井義昭
2006 - 鋼合成構造標準示方書の説明
奥井義昭
第11回鋼構造基礎講座「合成構造の設計と事例紹介」テキスト, 2006 - 硬岩の長期劣化予測を目的とした微視情報も算出可能な連続体理論の構築とその検証
奥井義昭; 小田匡寛
科学研究補助金研究成果報告書, 2006 - Ultimate Strength of Composite I-Girder in Pure Positive Bending
Nagai, M; Okui, Y; Inaba, N
7th Int. Conf. on Short & Medium Span Bridges, First page：ID-030-1-10, Last page：030-1-10, 2006 - FE Analysis with Smeared Crack Model for Crack Width Evaluation in Continuous Composite Girders
Okui, Y; Honda, Y; Khan, Q.Z; Nagai M
7th Int. Conf. on Short & Medium Span Bridges, First page：ID-034-1-7, Last page：034-1-7, 2006 - Effect of Initial Bending Moment in Composite Girder under Flexure for Unshored Construction
Gupta, V.K; Okui, Y; Nagai, M
7th Int. Conf. on Short & Medium Span Bridges, First page：ID-047-1-8, Last page：047-1-8, 2006 - 平成16年度鋼連続合成桁橋の構造合理化に関する技術検討報告書
長井正嗣,奥井義昭
（財）高速道路技術センター, 2005 - Rational design method for shear connector of composite girder bridges
奥井 義昭; 福永 靖雄
Volume：6, Number：6, First page：48, Last page：51, 2005
An analytical study on steel-concrete continuous composite girder bridges with precast concrete slab is carried out to investigate feasibility of composite bridges with precast concrete slabs. In composite girder bridges with precast concrete slab, the number of shear connectors is restricted owing to structural details of the precast panels. Accordingly, the effete of slip between the concrete slab and steel I girders on bridge behavior under service and ultimate loads is investigated to judge feasibility of composite girder bridges with precast concrete slab.
Japanese
ISSN：1347-4758, CiNii Articles ID：120001371355, CiNii Books ID：AA11808968 - 銀座線トンネル維持管理検討委員会報告書
魚本健人,奥井義昭
First page：1, Last page：380, 2005
東京地下鉄（株） - Ultimate strength of composite I-girder under pure sagging bending moment
Nagai M; Okui Y; Gupta V.K; Inaba N
First page：337, Last page：348, 2005 - Ultimate behavior and strength of composite girder under flexure - Proposition of innovative design method
Nagai M; Gupta V.K; Okui Y; Yasukawa Y; Inaba N
First page：4.3.91-98, 2005 - Simulation of Damage around a Circular Opening in Rock
Golshani A; Okui Y; Oda M
First page：33, Last page：40, 2005 - Simplified expressions for determining neutral axis depth in composite girders under positive bending
Gupta V.K; Okui Y; Nagai M
First page：53, Last page：56, 2005 - 平成16年度鋼連続合成桁橋の構造合理化に関する技術検討報告書
長井正嗣; 奥井義昭
（財）高速道路技術センター, 2005 - 合成桁のずれ止めの設計法に関する研究
奥井 義昭; 福永 靖雄
埼玉大学地域共同研究センター紀要, Volume：6, Number：6, First page：48, Last page：51, 2005
An analytical study on steel-concrete continuous composite girder bridges with precast concrete slab is carried out to investigate feasibility of composite bridges with precast concrete slabs. In composite girder bridges with precast concrete slab, the number of shear connectors is restricted owing to structural details of the precast panels. Accordingly, the effete of slip between the concrete slab and steel I girders on bridge behavior under service and ultimate loads is investigated to judge feasibility of composite girder bridges with precast concrete slab.
埼玉大学総合研究機構地域共同研究センター産学連携推進部門, Japanese
ISSN：1347-4758, CiNii Articles ID：120001371355, CiNii Books ID：AA11808968 - 銀座線トンネル維持管理検討委員会報告書
魚本健人; 奥井義昭
First page：1, Last page：380, 2005 - Ultimate strength of composite I-girder under pure sagging bending moment
Nagai M; Okui Y; Gupta V.K; Inaba N
The First International Road and Traffic Conference (ITRC), Proceedings -Roads to Global Society, Seoul, South Korea, First page：337, Last page：348, 2005 - Ultimate behavior and strength of composite girder under flexure - Proposition of innovative design method
Nagai M; Gupta V.K; Okui Y; Yasukawa Y; Inaba N
4th European conference on steel and composite structures, Eurosteel 2005, Maastricht, Netherlands, First page：4.3.91-98, Last page：98, 2005 - Simulation of Damage around a Circular Opening in Rock
Golshani A; Okui Y; Oda M
The 11th International Conference of IACMAG, Turin, Italy, First page：33, Last page：40, 2005 - Simplified expressions for determining neutral axis depth in composite girders under positive bending
Gupta V.K; Okui Y; Nagai M
Proceedings of the Seventh International Summer Symposium, JSCE, Tokyo, First page：53, Last page：56, 2005 - A METHOD FOR CRACK WIDTH EVALUATION OF CONTINUOUS COMPOSITE GIRDER BRIDGES ACCOUNTING FOR SHEAR-LAG EFFECT
KHAN Qaiser-uz-Zaman; HONDA Takuji; OKUI Yoshiaki; NAGAI Masatsugu
Number：738, First page：37, Last page：47, 21 Jul. 2003
English
ISSN：0289-7806, CiNii Articles ID：80016053243, CiNii Books ID：AN10014020 - 高減衰ゴムの微視構造の観察とマイクロメカニクスに基づく構成則の構築
奥井 義昭
科学研究費補助金基盤研究(C)(2)研究成果報告書, Volume：平成12-13年度, 2002 - 鋼コンクリート複合構造の力学特性解析法確立に関する研究
町田 篤彦,睦好 宏史,山口 宏樹,奥井 義昭,牧 剛史
科学研究費補助金(基盤研究(B)(2))研究成果報告書, Volume：平成11-13年度, 2002 - 高減衰ゴムの微視構造の観察とマイクロメカニクスに基づく構成則の構築
奥井 義昭
科学研究費補助金基盤研究(C)(2)研究成果報告書, Volume：平成12-13年度, 2002 - 鋼コンクリート複合構造の力学特性解析法確立に関する研究
町田 篤彦; 睦好 宏史; 山口 宏樹; 奥井 義昭; 牧 剛史
科学研究費補助金(基盤研究(B)(2))研究成果報告書, Volume：平成11-13年度, 2002 - Mechanical characteristics and constitutive models of high damping rubber for bridge bearings
OKUI Yoshiaki; Amin A.F.M. Saiful
Volume：2002, Number：2, First page：75, Last page：80, 2002
Fundamental mechanical characteristics of high damping rubber (HDR) for bridge bearings are introduced and reviewed through comparison with those of natural rubber (NR). Attention is given to behavior of HDR under compression. Rubber constitute models are addressed. Several hyperelastic models are compared for simulating HDR behavior with a constant strain rate. An improved hyperelasticity model is proposed to reproduce the rate-independent behavior of HDR including high initial stiffness at low stretch levels. The proposed hyperelastic model is incorporated into a rate-dependent finite-strain model structure.
Japanese
CiNii Articles ID：110002484301, CiNii Books ID：AA11901817 - 合成斜張橋の動向と技術的課題
長井 正嗣; 奥井 義昭; 岩崎 英治
Volume：35, Number：11, First page：27, Last page：34, Nov. 2001
Japanese
ISSN：0287-170X, CiNii Articles ID：40000754294, CiNii Books ID：AN00062923
- 鋼構造架設設計施工指針
鋼構造委員会; 鋼構造架設設計施工指針改定小委員会, [Joint work]
Jan. 2025
ISBN：9784810611212 - 土木構造設計2 [工業 752]
奥井 義昭, [Supervisor]
Jan. 2023
Japanese, Total pages：290
CiNii Books：http://ci.nii.ac.jp/ncid/BD01903827
ISBN：4407205636, ASIN：4407205636, EAN：9784407205633, CiNii Books ID：BD01903827 - 土木製図 [工業 706]
奥井義昭, [Supervisor]
Jan. 2022
Japanese, Total pages：251
CiNii Books：http://ci.nii.ac.jp/ncid/BC14375553
ISBN：4407204419, ASIN：4407204419, EAN：9784407204414, CiNii Books ID：BC14375553 - 鋼構造学
伊藤, 学; 奥井, 義昭, [Joint work]
Mar. 2020
Japanese, Total pages：viii, 245p
CiNii Books：http://ci.nii.ac.jp/ncid/BB29782611
ISBN：9784339052695, CiNii Books ID：BB29782611 - 窪田陽一監修，久保田尚, 奥井義昭他 道路が一番わかる：道路の構造・工法が手に取るように理解できる しくみ図解シリーズ
Oct. 2009
ISBN：4774140058 - 鋼橋性能向上研究委員会・合理化設計法部会, 奥井義昭 合成桁の限界状態設計法試案 JSSCテクニカルレポート
2006 - 鋼橋性能向上研究委員会・合理化設計法部会, 奥井義昭 合成桁の限界状態設計法試案 JSSCテクニカルレポート
社）日本鋼構造協会, 2006 - Continuum models for materials with microstructure
Okui, Y.; Horii, H.; Ed.Mühlhaus; H, [Contributor], Chapter 2 A Micromechanics-based Continuum Theory for Microcracking Localization of Rocks under Compression
Wiley, Mar. 1996
English, Total pages：492
CiNii Books：http://ci.nii.ac.jp/ncid/BA26435851
ISBN：0471950653, ASIN：0471950653, EAN：9789810244125, CiNii Books ID：BA26435851
- 鋼トラス橋を対象としたリダンダンシー評価ガイドラインの開発
2009 - プレキャスト床版連続合成桁のスタッドに関する実験
2009 - 低塔を有する200m合成斜張橋の弾塑性挙動と終局強度
2009 - 合成桁中間支点部の曲げ強度評価に関する一考察
2009 - Seismic response analysis of base isolated highway bridge:effect of isolation bearing's modeling
2009 - A Simplified Rheology Model of Natural and Lead Rubber Bearings for Seismic Analysis
2009 - 鋼トラス橋を対象としたリダンダンシー評価ガイドラインの開発
2008年度公募研究成果梗概集, 2009 - プレキャスト床版連続合成桁のスタッドに関する実験
土木学会第64回年次学術講演会, 2009 - 低塔を有する200m合成斜張橋の弾塑性挙動と終局強度
土木学会第64回年次学術講演会, 2009 - 合成桁中間支点部の曲げ強度評価に関する一考察
土木学会第64回年次学術講演会, 2009 - Seismic response analysis of base isolated highway bridge:effect of isolation bearing's modeling
土木学会第64回年次学術講演会, 2009 - A Simplified Rheology Model of Natural and Lead Rubber Bearings for Seismic Analysis
土木学会第64回年次学術講演会, 2009 - 耐震設計用レオロジーモデルとパラメータの同定：RBとLRBの場合
2008 - Experimental investigation of laminated rubber bearings and their modeling: High damping rubber bearing
2008 - 塑性中立軸が床版内にある合成I桁の正曲げ強度に関する実験的研究
2008 - 鋼トラス橋のリダンダンシー評価手法の検討（その３）
2008 - 鋼トラス橋のリダンダンシー評価手法の検討（その２）
2008 - 鋼トラス橋のリダンダンシー評価手法の検討（その１）
2008 - せん断を受けるI桁のエンドパネルの影響に関する実験検討
2008 - NONLINEAR VISCOSITY OF HIGH DAMPING RUBBER BEARINGS: EXPERIMENTAL INVESTIGATION AND RHEOLOGY MODEL
2008 - Strength of headed stud shear connectors in steel-concrete composite beams with precast decks
2008 - Experimental investigation of laminated rubber bearings at low temperatures
2008 - 曲げとせん断を受けるハイブリッドI桁の耐力に関する実験検討
2008 - 耐震設計用レオロジーモデルとパラメータの同定：RBとLRBの場合
第63回土木学会北海道支部, 2008 - Experimental investigation of laminated rubber bearings and their modeling: High damping rubber bearing
64th JSCE Annual Conference Hokkaido, 2008 - 塑性中立軸が床版内にある合成I桁の正曲げ強度に関する実験的研究
土木学会第63回年次学術講演会, 2008 - 鋼トラス橋のリダンダンシー評価手法の検討（その３）
土木学会第63回年次学術講演会, 2008 - 鋼トラス橋のリダンダンシー評価手法の検討（その２）
土木学会第63回年次学術講演会, 2008 - 鋼トラス橋のリダンダンシー評価手法の検討（その１）
土木学会第63回年次学術講演会, 2008 - せん断を受けるI桁のエンドパネルの影響に関する実験検討
土木学会第63回年次学術講演会, 2008 - NONLINEAR VISCOSITY OF HIGH DAMPING RUBBER BEARINGS: EXPERIMENTAL INVESTIGATION AND RHEOLOGY MODEL
土木学会第63回年次学術講演会, 2008 - Strength of headed stud shear connectors in steel-concrete composite beams with precast decks
Proceedings of the Tenth International Summer Symposium, JSCE, 2008 - Experimental investigation of laminated rubber bearings at low temperatures
Proceedings of the Tenth International Summer Symposium, JSCE, 2008 - 曲げとせん断を受けるハイブリッドI桁の耐力に関する実験検討
土木学会第63回年次学術講演会, 2008 - 合成I桁の曲げ耐荷力の実験検討
2007 - 合成I桁の曲げ強度評価に関する一考察
2007 - A rheology model of rubber bearing for seismic analysis of bridges
2007 - 積層ゴム支承の地震応答解析用レオロジーモデル
2007 - 水平スタッドのせん断特性に関する実験的研究（その２） せん断強度の評価
2007 - 水平スタッドのせん断特性に関する実験的研究（その1） 水平スタッドの終局挙動
2007 - A rheology model of rubber bearing for seismic analysis of bridges
2007 - ２重合成Ｉ桁中間支点部の曲げ耐力に関する実験検討
2007 - Design of Composite Bridges-Lateral Distortional Buckling-
2007 - Web Slenderness Limits for Section Classification of Composite Girders
2007 - Development of Steel/Concrete Hybrid Bridges in Japan
2007 - Load carrying capacity of cable-stayed composite girder bridges with segmental cantilever erection
2007 - ゴム支承を対象とした耐震設計用レオロジーモデル
2007 - Development of hybrid bridges and design innovation in Japan
2007 - Design issues for steel-concrete composite girders,
2007 - Composite bridges in Japan
2007 - 合成I桁の曲げ耐荷力の実験検討
土木学会第61回年次学術講演会概要集, 2007 - 合成I桁の曲げ強度評価に関する一考察
土木学会第61回年次学術講演会概要集, 2007 - A rheology model of rubber bearing for seismic analysis of bridges
9th JSCE International Summer Symposium, Yokohama, Japan, 2007 - 積層ゴム支承の地震応答解析用レオロジーモデル
土木学会第62回年次学術講演会概要集, 2007 - 水平スタッドのせん断特性に関する実験的研究（その２） せん断強度の評価
土木学会第62回年次学術講演会概要集, 2007 - 水平スタッドのせん断特性に関する実験的研究（その1） 水平スタッドの終局挙動
土木学会第62回年次学術講演会概要集, 2007 - A rheology model of rubber bearing for seismic analysis of bridges
土木学会第62回年次学術講演会概要集, 2007 - ２重合成Ｉ桁中間支点部の曲げ耐力に関する実験検討
土木学会第62回年次学術講演会概要集, 2007 - Design of Composite Bridges-Lateral Distortional Buckling-
Japan-Korea joint workshop on steel bridge design specification, Hokkaido univ., Japan, 2007 - Web Slenderness Limits for Section Classification of Composite Girders
Proc. of JSCE-EIT Joint Seminar on Recent code development and advanced technologies of steel and composite bridges, 2007 - Development of Steel/Concrete Hybrid Bridges in Japan
Proc. of JSCE-EIT Joint Seminar on Recent code development and advanced technologies of steel and composite bridges, 2007 - Load carrying capacity of cable-stayed composite girder bridges with segmental cantilever erection
Proc. of SIIT-Saitama University joint seminar, 2007 - ゴム支承を対象とした耐震設計用レオロジーモデル
土木学会北海道支部年次技術研究発表会概要集, 2007 - Development of hybrid bridges and design innovation in Japan
Proc. of China-Japan joint seminar on steel and composite bridges, 2007 - Design issues for steel-concrete composite girders,
Proc. of China-Japan joint seminar on steel and composite bridges, 2007 - Composite bridges in Japan
Proc. of Japan-China Conference on Structural Steel Construction, 2007 - 合成桁の断面分類と強度式の検討
2006 - 合成I桁の曲げ強度評価におけるductility条件
2006 - Lateral distortional buckling of steel and concrete composite twin I-girder
2006 - Topics on Strength, Section Classification, Ductility requirements of Composite Girders in Japan
2006 - Crack Width Evaluation Method accounting for shear-lag effect and effective width
2006 - On design of composite girder bridges
2006 - 高減衰ゴムの非線形粘性則の同定と有限ひずみ構成則でのシミュレーション,
2006 - Web Slenderness Ratio Considering Initial Bending Moment Effect on Composite Girders during Construction Phase
2006 - Topics on ultimate strength of composite girders in Japan
2006 - 合成桁の断面分類と強度式の検討
土木学会関東支部新潟会研究調査発表会概要集, 2006 - 合成I桁の曲げ強度評価におけるductility条件
土木学会関東支部新潟会研究調査発表会概要集, 2006 - Lateral distortional buckling of steel and concrete composite twin I-girder
土木学会関東支部新潟会研究調査発表会概要集, 2006 - Topics on Strength, Section Classification, Ductility requirements of Composite Girders in Japan
Proc. of Korea-Japan Joint Seminar on Steel-Concrete Composite Bridges, 2006 - Crack Width Evaluation Method accounting for shear-lag effect and effective width
Proc. of Korea-Japan Joint Seminar on Steel-Concrete Composite Bridges, 2006 - On design of composite girder bridges
Proc. of Vietnum-Japan joint seminar on steel bridges, 2006 - 高減衰ゴムの非線形粘性則の同定と有限ひずみ構成則でのシミュレーション,
土木学会第61回年次学術講演会概要集, 2006 - Web Slenderness Ratio Considering Initial Bending Moment Effect on Composite Girders during Construction Phase
土木学会第61回年次学術講演会概要集, 2006 - Topics on ultimate strength of composite girders in Japan
Korea-Japan Joint Workshop on Steel Bridge Design Specifications, 2006 - 合成桁の終局曲げ強度特性の解明に関する研究
2005 - 逆解析手法による高減衰ゴムの非線形粘性則の同定
2005 - 連続合成桁の初期ひび割れ性状の解明に関する実験的研究,
2005 - 合成桁におけるずれ止めの限界状態設計のための解析的研究
2005 - ずれ止めの変形を考慮した連続合成桁の3次元FEM解析
2005 - The effect of initial moment on the ultimate load-carrying capacity of composite girder under flexure
2005 - On Analytical Study for Steel-Concrete Compopsite Girders, Seminar on Recent Advances in Steel Bridges in Japan
2005 - 合成桁の終局曲げ強度特性の解明に関する研究
土木学会第60回年次学術講演会講演概要集,, 2005 - 逆解析手法による高減衰ゴムの非線形粘性則の同定
土木学会第59回年次学術講演会講演概要集, 2005 - 連続合成桁の初期ひび割れ性状の解明に関する実験的研究,
土木学会第60回年次学術講演会講演概要集, 2005 - 合成桁におけるずれ止めの限界状態設計のための解析的研究
土木学会第60回年次学術講演会講演概要集, 2005 - ずれ止めの変形を考慮した連続合成桁の3次元FEM解析
土木学会第60回年次学術講演会講演概要集, 2005 - The effect of initial moment on the ultimate load-carrying capacity of composite girder under flexure
60th Annual Proceeding of Japanese Society of Civil Engineers, JSCE, Japan, 2005 - On Analytical Study for Steel-Concrete Compopsite Girders, Seminar on Recent Advances in Steel Bridges in Japan
Proc. of Bridge Engneering, 2005 - Some topics of studies for steel-concrete composite girders
Okui Y; Gupta V.K
Proc. of 8th Korea-China-Japan Symposium on steel structure, Seoul, 2005 - Load-carrying capacity of composite girders in cable-stayed bridges
Okui Y; Nagai M; Iwasaki E; Hirono T
4th European conference on steel and composite structures, Eurosteel 2005, Maastricht, Netherlands, 2005 - Proceedings of the Japan-Bangladesh Joint SEminar on Advances in Bridges Eng.
Amin; A.F.M.S; Okui, Y; Safiullah; A.M.M editor
The instituton of Engineers, Bangladsh, 2005 - Hydraulic behaviour of Inada granite in the excavation disturbed zone around underground openings
Golshani, A; Okui, Y; Oda, M; Takemura, T
Proceedings of the Seventh International Summer Symposium, JSCE, Tokyo, 2005 - Analytical study on steel-concrete composite girders
Okui Y
Proc. of Japan-Bangladesh Joint Seminar on Advances in Bridge Engineering, Dhaka, Bangladesh, 2005 - 連続合成２主桁橋のひび割れ幅算定を目的とした有効幅の検討
2004 - 連続合成２主桁橋のひび割れ幅算定を目的とした有効幅の検討
土木学会第59回年次学術講演会講演概要集, 2004 - Time dependent continuous damage model for brittle failure of rocks
Golshani, A; Okui, Y; Takemura, T; Oda
EUROCK 2004 & 53rd Geomechanics Colloquium, Schubert (ed.), 2004
■ Affiliated academic society
■ Research projects
- Development of an existing bridge management method based on load rating
Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (B), 01 Apr. 2021 - 31 Mar. 2024
Saitama University
Grant amount(Total)：15340000, Direct funding：11800000, Indirect funding：3540000
Grant number：21H01415 - Development of design procedure for high damping rubber bearings under low temperatures and modeling of Mullins' effect
Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (B), 01 Apr. 2014 - 31 Mar. 2017
OKUI Yoshiaki; IMAI Takashi, Saitama University
Grant amount(Total)：15470000, Direct funding：11900000, Indirect funding：3570000
The temperature dependence of mechanical characteristics of high damping rubber bearings (HDRBs) was investigated through cyclic loading tests under different ambient temperatures, especially sub-zero environment. The ambient temperatures and temperatures inside HDRBs during cyclic loading were
different due to self hating, and it is found that mechanical behavior of HDRBs is governed by the inside temperatures. A simple method to estimate the inside temperature was developed on the basis of the cyclic loading tests and thermal conductivity analyses results. Previous cyclic loading tests results at different ambient temperatures were reexamined based on the inside temperatures to estimate temperature dependence of HDRBs.
Grant number：26289140
受賞ID：4206770 - Mechanism of damage-induced local damping and structural health monitoring of bridges based on damping change
Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (A), 01 Apr. 2011 - 31 Mar. 2015
YAMAGUCHI Hiroki; MATSUMOTO Yasunao; OKUI Yoshiaki; ASAMOTO Shingo; MUTSUYOSHI Hiroshi, Saitama University
Grant amount(Total)：42250000, Direct funding：32500000, Indirect funding：9750000
Damages (such as tension crack, corrosion and partial fracture) and damage –induced local damping increment in steel member, concrete member and steel-concrete interface are first experimentally studied to discuss the mechanism of local damping increased by local damages. The evaluation method of structural health condition for steel, RC and PC bridges is then proposed by developing a hybrid method of experimental and analytical modal syntheses based on ambient vibration measurement and global damping change monitoring. The method of ambient vibration measurement is carefully studied for optimizing it as a system and the identification of global damping change in bridges is refined with FE model updating method. How to implement the proposed method of bridge health evaluation to the Bridge Management System was finally discussed.
Grant number：23246082 - Development of a rheology model of laminated rubber bearings for seismic design: Establishment of design method at low temperature
Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (C), 2010 - 2012
OKUI Yoshiaki, Saitama University
Grant amount(Total)：4290000, Direct funding：3300000, Indirect funding：990000
A seismic design model of base-isolation rubber bearings for nonlinear dynamic analyses is investigated especially under low temperature conditions. The rubber bearing tests are carried out in low temperatures environment up to -30 C deg. to identify temperature dependency of mechanical behavior. A rheology model including elastic-visco-plastic elements is developed to reproduce strain-rate dependent response prominent in high damping rubber bearings and elastic-plastic response in lead rubber bearings.
Grant number：22560473
受賞ID：4206770 - Structural redundancy/collapse analysis, dynamic analysis and structural health monitoring of steel truss bridges
Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (B), 2008 - 2010
YAMAGUCHI Hiroki; OKUI Yoshiaki; MATSUMOTO Yasunao; YOSHIOKA Tsutomu; ITO Shin, Saitama University
Grant amount(Total)：18590000, Direct funding：14300000, Indirect funding：4290000
The fracture critical members were identified by conducting the structural redundancy analysis of steel truss bridges and the effects of load-carrying capacity of concrete deck as well as member joint were investigated. The dynamic characteristics of truss bridges, classified into the global, local and coupled modes, were also clarified in detail by the experimental/theoretical modal analyses. The feasibility of vibration-based health monitoring of steel truss bridges, based on the field measurement as well as the impulse hummer test, was finally discussed by showing the fact that the damping ratios of coupled modes and the group of higher natural frequencies in local modes can be changed in identifiable amount by having local damages in truss diagonal members.
Grant number：20360198 - Development of the most competitive performance-based limit state design method for composite girders
Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (B), 2006 - 2007
NAGAI Masatsugu; OKUI Yoshiaki; IWASAKI Eiji, Nagaoka University of Technology
Grant amount(Total)：16740000, Direct funding：15300000, Indirect funding：1440000
Performance-based Limit State Design Method (PB-LSD) for designing structural members for infrastructure is now global standard. In Euro Code (EU) and AASHTO LRFD (USA), after 20-year energetic activity, the shift of design concept from Allowable Stress Design (ASD) to PB-LSD has just finished. Among Asian countries, where future preparation of infrastructure is expected and also are expected to be promising market, the above codes are now becoming popular. In Japan, for more than 30 years, ASD has been used. On designing composite girders, which is competitive structural members, and has been employed worldwide, in order to effectively utilize its mechanical characteristics, introduction of LSD is inevitable. From a viewpoint of competing with EC (EU) and AASHTO LRFD (USA), a shift from ASD to LSD has to be done immediately. In this research, based on analytical and experimental studies, original and competitive formulae for evaluating ultimate flexure, shear and interactive strength for composite girders were proposed, which are the most important items on establishing competitive LSD. On evaluating flexural strength, the criterion for judging to be compact section gives the most economical section. Regarding ductility condition taking into account of the decrease of plastic moment due to concrete crushing, the most competitive solution was given. On evaluating flexure and shear interactive strength, it was found that the interaction effect can be neglected in case of composite girders. In case of steel girder (under erection), it has to be checked. Original provisions were also proposed on checking serviceability limit state. Furthermore, the design method for double-composite girders and composite hybrid girders was also proposed.
Grant number：18360214 - Establishment of Analytical Methodology for Mechanical,Characteristics of Steel-Concrete Hybrid Structures
Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (B), 1999 - 2001
MACHIDA Atsuhiko; OKUI Yoshiaki; YAMAGUCHI Hiroki; MUTSUYOSHI Hiroshi; TAKESI Maki, Saitama University
Grant amount(Total)：8300000, Direct funding：8300000
(1) A FEM program was developed to analyze the mechanical behavior of hybrid structures in which steel girders are rigidly connected to RC pier. In this program, concrete was assumed as homogeneous material, and Mohr-Coulomb's failure criterion was adopted considering strain softening. In order to treat bonding phenomena between concrete and reinforcing bar or steel plate rigorously, bonding elements were developed based on the previously proposed models and incorporated into the program. In particular, the bonding element between concrete and steel plate can express slip and exfoliation phenomena. The developed program can be applied to composite structures in general.
(2) Comparison of analysis with experimental results showed that the developed program can trace the behavior accurately up to large deformation region.
(3) Analysis on the hybrid structures of actual scale showed that, unless some special measures are taken, most of the load from super structure is transferred to the connection and its vicinity, hardly distributing to the lateral direction.
(4) A strut and tie model, which can analyze the behavior more simply and can be used as design tool, was developed based on the analysis.
Grant number：11450169 - 結晶性硬岩の超長期劣化問題に対する解析モデルの開発
Competitive research funding - 橋梁維持管理のためのリダンダンシーやVulnerability assessmentに関する研究
Competitive research funding - 橋梁用ゴム支承の耐震設計用レオロジーモデルの開発とゴム支承の温度依存性に関する研究
Competitive research funding - 橋梁設計における安全係数の合理的決定法に関する研究
Competitive research funding - 鋼橋および合成桁の設計法に関する研究
Competitive research funding - Development of super long-term deterioration prediction models for crystalline rocks
Competitive research funding - Redundancy and vulnerability assessment of steel structures for bridge maintenance
Competitive research funding - Mechanical model of laminated rubber bearings for seismic design
Competitive research funding - Research on safety factors for structural design
Competitive research funding - Design method for steel and composite structures
Competitive research funding