MF研究者総覧

Researcher Database

Advance
Shoji Yokohama
Faculty of Engineering　Civil Engineering　Natural Disasters and Adaptation
Assistant Professor
Researchers' Page on researchmap
Last Updated :2024/05/09

Researcher Profile and Settings

Affiliation

  • Faculty of Engineering　Civil Engineering　Natural Disasters and Adaptation

Job Title

  • Assistant Professor

Degree

  • Doctor of Engineering（Hokkaido University）

URL

Research funding number

  • 50299731

J-Global ID

Research Interests

  • 地盤工学   Geomechanics   

Research Areas

  • Social infrastructure (civil Engineering, architecture, disaster prevention) / Geotechnical engineering

Educational Organization

Education

  • 1995/04 - 1997/03  Muroran Institute of Technology  Graduate School of Engineering
  • 1991/04 - 1995/03  Muroran Institute of Technology  Faculty of Engineering  Department of Civil Engineering and Architecture

Association Memberships

  • 土木学会   地盤工学会   ISSMGE   ISSMGE   Japan Society of Civil Engineers   The Japanese Geotechnical Society   

Research Activities

Published Papers

  • Shoji Yokohama
    International Journal of GEOMATE 22 (89) 2186-2982 2022/01/01 [Refereed]
  • Shoji Yokohama
    Japanese Geotechnical Society Special Publication 9 (9) 418 - 423 2021/10/12 [Refereed][Not invited]
  • Study on ground strengthening and power generation by using both of recycled asphalt pavement material and temperature of ground surface
    Shoji Yokohama
    第14回環境地盤工学シンポジウム発表論文集 207 - 212 2021/09
  • Tatsuya Ishikawa, Masayuki Yoshimi, Koichi Isobe, Shoji Yokohama
    Soils and Foundations 61 (4) 1151 - 1171 0038-0806 2021/08
  • Shoji Yokohama
    第14回地盤改良シンポジウム論文週 271 - 276 2020/12
  • Atsuko Sato, Osamu Hatakeyama, Kakuto Morita, Shoji Yokohama
    Japanese Geotechnical Society Special Publication 8 (5) 149 - 154 2020/03/14
  • Shoji Yokohama
    第13回環境地盤工学シンポジウム発表論文集 351 - 358 2019/09 [Refereed][Not invited]
  • Shoji Yokohama
    International Journal of GEOMATE 16 (58) 2186-2982 2019/06/01 [Refereed][Not invited]
  • 地盤補強-発電-廃材リユースのトータルシステム具現化に関する基礎的検討
    横浜 勝司
    地盤工学会北海道支部技術報告集 59 9 - 16 2019/01 [Refereed][Not invited]
  • アスファルト廃材の長期圧縮挙動と排水強度特性
    横浜 勝司, 佐藤 厚子
    第13回地盤改良シンポジウム論文集 13 437 - 442 2018/10 [Refereed][Not invited]
  • アスファルト廃材を用いた盛土の現地調査
    松本博志, 佐藤厚子, 横濱勝司
    全地連「技術フォーラム2017」旭川 発表論文 2017 [Not refereed][Not invited]
  • アスファルト廃材の混合による砂質土の繰返し強度向上に関する研究
    横浜勝司, 佐藤厚子
    第12回環境地盤工学シンポジウム発表論文集 12 53 - 58 2017 [Refereed][Not invited]
  • アスファルト廃材の地盤材料としての性質
    佐藤厚子, 横浜勝司
    第12回環境地盤工学シンポジウム発表論文集 12 47 - 52 2017 [Refereed][Not invited]
  • アスファルト廃材の地盤改良材としての有効活用
    佐藤厚子, 林憲裕, 横浜勝司
    第12回地盤改良シンポジウム論文集 12 307 - 314 2016 [Refereed][Not invited]
  • アスファルト廃材と砂質土の混合材の静的力学特性
    横浜勝司, 佐藤厚子
    第12回地盤改良シンポジウム論文集 12 301 - 306 2016 [Refereed][Not invited]
  • アスファルト廃材を用いた土構造物の保護に関する研究
    横浜勝司, 佐藤厚子
    地盤工学会誌 64 (11/12) 34 - 35 2016 [Refereed][Not invited]
  • S. Yokohama
    VOLCANIC ROCKS AND SOILS 103 - 104 2016 [Refereed][Not invited]
     
    In order to prevent ground disasters on volcanic soils, the mechanical properties have to be cleared in detail. In this study, the mechanical characteristics of a volcanic soil which have deposited in Japan were investigated by a series of laboratory tests. The arrangements of soil particles of the compacted specimens were also observed with a microscope. Based on the test results, the effects of compaction condition such as the difference of water content on the undrained strength was discussed. From the results of cross-sectional observation, it was found that the trends of arrangements of soil particles were influenced by the water contents at compaction work. Finally, the undisturbed specimens were sampled on site of slope failure. The undrained strength and soil structure were also discussed in this study.
  • アスファルト再生材と豊浦砂の混合材料に関する力学特性
    横浜勝司, 福島宏文
    第11回環境地盤工学シンポジウム論文集 269 - 274 2015/07 [Refereed][Not invited]
  • アスファルト再生骨材と笠岡粘土の混合材の力学特性に関する研究
    福島宏文, 横浜勝司, 山梨高裕, 佐藤厚子
    第11回環境地盤工学シンポジウム論文集 261 - 268 2015/07 [Refereed][Not invited]
  • Satoshi Matsumura, Seiichi Miura, Shoji Yokohama, Shima Kawamura
    SOILS AND FOUNDATIONS 55 (1) 86 - 98 0038-0806 2015/02 [Refereed][Not invited]
     
    The aim of this paper was to clarify the effect of freeze-thawing on the cyclic shear behavior of a crushable volcanic soil that is widely deposited in Hokkaido, Japan. Using a traxial apparatus, which was newly developed to simulate freeze thaw cycles and cyclic loading, a series of cyclic triaxial tests was performed on compacted volcanic soils subjected to freeze thaw cycles. The experimental results showed that freeze-thawing leads to a significant decrease in the liquefaction strength of densely-compacted volcanic soils. The decrement in liquefaction strength depended strongly on the behavior of the excess pore water pressure during cyclic loading. In addition, according to the variation in cyclic deformation behavior induced by the freeze thaw sequence, it was anticipated that the freeze-thawing would be related to the change in the soil fabric of the specimens. However, the specimens compacted at a lower dry density seemed to be inconsistent with the above; i.e., the liquefaction strength became almost the same regardless of whether or not the specimens were exposed to the freeze-thaw sequence. Thus, it was concluded that the freeze-thaw sequence can degrade the dynamic properties of volcanic soil, but that such influences ought to be incorporated into a correlation with the dry density. (C) 2015 The Japanese Geotechnical Society. Production and hosting by Elsevier B.V. All rights reserved.
  • Srikrishnan Siva Subramanian, Tatsuya Ishikawa, Shoji Yokohama, Tetsuya Tokoro
    6th Japan-China Geotechnical Symposium, SJGS 2015 5 - 10 2015 [Refereed][Not invited]
     
    Slope instability issues due to freeze-thaw action, rainfall and seismicity are common in cold regions like Hokkaido. It is essential to study the varied impacts of temperature difference and infiltration due to rainfall on soil slope stability. The main objective of this study is to find a suitable slope stability assessment method considering the effects of freeze-thaw and rainfall. An embankment slope failure study performed by previous researchers has been numerically simulated. A modelling methodology to perform freeze-thaw, seepage and limit equilibrium slope stability analysis has been adopted and followed. Crucial parameters for slope stability i.e. initial moisture content, moisture content distribution during failure were obtained from the simulation and then compared with the measurement data. The numerical results compared with the measured data provide rational satisfaction and demonstrate the applicability of the software code in order to predict the stability of slope. The numerical modelling approach used in this study is found useful in analysing the rational stability of soil slopes and to simulate the moisture content distribution of slopes subjected to freeze-thaw and rainfall infiltration.
  • Shoji Yokohama, Seiichi Miura, Satoshi Matsumura
    SOILS AND FOUNDATIONS 54 (4) 731 - 747 0038-0806 2014/08 [Refereed][Not invited]
     
    In recent years, earthquakes and heavy rains have frequently caused soil embankments to collapse. In order to prevent the collapse of embankments, it is well known that sufficient compaction and drainage control are necessary. Although numerous research findings have described compacted soils, compaction management has been essentially based on simple parameters such as dry density, degree of saturation or air content. It is important for the construction of a stiff embankment that the effect of compaction condition on the mechanical properties and inherent anisotropy of compacted soil should be recognized in detail. In the present study, the relationships between the compaction condition and the mechanical properties obtained from laboratory tests using saturated specimens are presented. Specifically, undrained monotonic and cyclic shear strength, shear modulus, and permeability are reported. The arrangements of soil particles were also observed with a microscope. From the observation of fabric characteristics of soil particles, an inherent anisotropy of compacted soil is discussed. Furthermore, a conceptualization of the relationship between the fabric of soil particles and the mechanical characteristics for each compaction condition is suggested. (C) 2014 The Japanese Geotechnical Society. Production and hosting by Elsevier B.V. All rights reserved.
  • 松村聡, 三浦清一, 横浜勝司
    Doboku Gakkai Ronbunshuu C Japan Society of Civil Engineers 68 (4) 597 - 609 2185-6516 2012/11 [Refereed][Not invited]
     
    Embankment structures in Japan have been subjected to a large number of earthquakes and as a result some of them leads to the failure of embankments. Therefore it can be unavoidable to develop the evaluation of seismic performance and the seismic design to constructed embankments. At present embankment is constructed fundamentally by managing degree of compaction Dc (%) at higher water content than the optimum water content wopt (%). However, it is pointed out that the difference of water content at compaction has some effects on mechanical characteristics of compacted soil even if the same degree of compaction is obtained. Furthermore, it has been gradually revealed that the mechanical characteristics can be remarkably improved due to achieving as the high degree of compaction as possible.
     Keeping in view the above, a series of cyclic undrained triaxial tests was carried out on compacted and saturated sandy-silt soil, which was actually adopted as a dike material. The specimens were prepared by compaction at the different water content with various compaction energy Ec (kN/m3) in order to compare with effects of compaction condition such as the degree of compaction and water content on seismic characteristics. Experimental results show that the samples compacted at lower water content than the optimum water content wopt (%) are stronger than the samples compacted at higher water content than wopt under the same degree of compaction. It is also confirmed that the deformation due to cyclic loading develops rapidly at drier side of wopt rather than at wetter side of wopt. Thus, it is inferred that seismic performance of embankment greatly relies on some factors such as degree of compaction and water content.
  • Mechanical properties and soil fabric of compacted embankment
    YOKOHAMA Shoji
    Proceedings of International conference on gound improvement and ground control(IGCI Wollongong 2012) 1089 - 1094 2012/10 [Refereed][Not invited]
  • Seismic behavior of embankment constructed by different compaction methods
    MATSUMUIRA Satoshi, MIURA Seiichi, YOKOHAMA Shoji
    Proceedings of International conference on gound improvement and ground control(IGCI Wollongong 2012) 1047 - 1053 2012/10 [Refereed][Not invited]
  • Bearing capacity improvement of anisotropic sand ground and its evaluation
    KAWAMURA Shima, MIURA Seiichi, YOKOHAMA Shoji
    Proceedings of International conference on gound improvement and ground control(IGCI Wollongong 2012) 755 - 761 2012/10 [Refereed][Not invited]
  • 横浜勝司, 三浦清一, 松村聡
    Doboku Gakkai Ronbunshuu C Japan Society of Civil Engineers 68 (2) 422 - 432 2185-6516 2012/06 [Refereed][Not invited]
     
    In order to reveal change in mechanical characteristics of soil due to difference of compaction condition, a series of laboratory tests on sandy silt which was used as embankment material are performed. In those tests, shear strength, shear modulus and coefficient of permeability are measured under the various compaction conditions. Firstly, it is shown that shear strength of the specimen prepared at the optimum water content is higher than these of drier and wetter condition at the lower confining pressure. On the other hand, it is found that vertical permeability and shear modulus of the specimens depend on the degree of compaction and water content at compaction. At the same compaction energy, the permeability and the shear modulus show the minimum and maximum values at the wetter situation. Those experimental facts are reflected to the change in the soil fabric of specimen due to the compaction. In order to reveal the correlations among the shear strength, shear modulus and permeability coefficient prepared at the various compaction conditions are graphically-illustrated. Those explain that (1) increase of the permeability coefficient makes the strength reduction, (2) the shear strength increase in almost directly proportion to the shear modulus of compacted specimen. In this study, it is attempted to express the patterns for fabrics of compacted soil. At the compaction under drier condition, the finer particles generally stand up and coarse particles lay horizontally. By contrast, under wetter condition, the finer particles lay horizontally and coarse particles almost stand up. Those may explain reasonably the effects of condition of compaction on the mechanical properties.
  • TAJIKA Jun, ISHIMARU Satoshi, KAWAKAMI Gentaro, OKAZAKI Noritoshi, YOKOHAMA Shoji, MIURA Seiichi
    Landslides The Japan Landslide Society 49 (2) 75 - 79 1348-3986 2012/03/25 [Not refereed][Not invited]
  • S. Yokohama, S. Miura, S. Matsumura
    ADVANCES IN TRANSPORTATION GEOTECHNICS II 364 - 369 2012 [Refereed][Not invited]
     
    In this study, mechanical characteristics of soil material used to construct river embankment were investigated by a series of laboratory test. The soil has the maximum grain size of 2.0 mm, finer contents of 68.1% and plastic index of 12.3%. The maximum dry density and the optimum water content by compaction tests using an energy level of 1.13Ec, where Ec denoted the standard Proctor test, are 1.446 g/cm(3) and 25.0%, respectively. To evaluate effects of compaction condition on the shear strength and other mechanical behavior of the soil, the specimens are prepared by compaction under various conditions in terms of dry density, water contents and compaction energy. The relationships between the compaction condition and the mechanical properties from the test on saturated specimens are presented in this paper. It is shown that the micro-fabric of compacted soil is controlled not only compaction energy but also water content at compaction and the mechanical properties are affected by not only dry density but also the micro-fabric.
  • S. Matsumura, S. Miura, S. Yokohama
    ADVANCES IN TRANSPORTATION GEOTECHNICS II 334 - 339 2012 [Refereed][Not invited]
     
    The islands of Japan have been subjected to a large number of earthquakes. Recent big earthquakes destroyed embankment structures. In order to avoid damages of embankment, it is important to reveal effects of compaction conditions such as degree of compaction D-c and water content at compaction w(i) on seismic performance of embankment. In this research, a series of cyclic undrained triaxial test was carried out on saturated sandy-silt soil, which was actually adopted as a dike material. The specimens were compacted at the optimum water content w(opt), drier condition and wetter condition than wopt with different compaction energies E-c (kN/m(3)) to each specimen. The experimental results definitely indicate that dynamic behavior is significantly influenced by compaction condition.
  • S. Kawamura, S. Miura, S. Yokohama
    Geotechnical Special Publication (211) 3598 - 3608 0895-0563 2011 [Not refereed][Not invited]
     
    This paper aims at clarifying failure mechanisms of volcanic slope with crushable particles due to rainfall and freeze-thaw action. A series of rainfall tests was performed on model volcanic slopes having several water contents and slope angles. Considering the model test results, it was found that surface slope failure was changed depending strongly on slope angle and the initial water content. Furthermore, it was shown that the effect of freeze-thaw action on mechanical behavior for volcanic slope having high crushable particles was higher than that for volcanic slope having low crushable particles, and could not be ignored for evaluation of slope stability. © 2011 ASCE.
  • Shima Kawamura, Seiichi Miura, Shoji Yokohama
    SOILS AND FOUNDATIONS 50 (5) 645 - 657 0038-0806 2010/10 [Not refereed][Not invited]
     
    An experimental study on the mechanical response of anisotropic seabed to wave force and oscillation of man-made structures such as wave dissipating blocks and breakwaters was performed on a model soil box with two-dimensional plane strain condition. Using model ground comprised of Toyoura sand reconstituted by air-pluviation method, a series of cyclic loading tests on model structures under several foundation conditions was conducted at a loading pattern which is capable of simulating the various stress states induced by both oscillation of structure and wave force. Test results showed that the strength and deformation characteristics of model sand deposits are basically identical to those estimated from the conventional cyclic undrained triaxial test and are different depending strongly on the changes in the depositional condition of the ground. Based on the results of model testing, the applicability of countermeasures constructed by both side wall and sheet pile was investigated to prevent ground failure. Considering the model testing results, it was also found that the installation of side walls beneath structures and sheet piles into the ground are advantageous as countermeasures against progressive failure on sand ground subjected to wave loading.
  • TAKIMOTO Shogo, MIURA Seiichi, KAWAMURA Shima, YOKOHAMA Shoji
    PROCEEDINGS OF THE JAPANESE CONFERENCE ON COASTAL ENGINEERING Japan Society of Civil Engineers 66 (No.1-B2-66) 906 - 910 1884-2399 2010 [Not refereed][Not invited]
     
    This paper presents the fundamentals of mechanical behavior of anisotropic sand beds subjected to the loading by wave-structure interactions. A series of model tests was performed on a model structure by using the soil box with two-dimensional plane strain condition and the Toyoura sand ground to clarify mechanical behavior of the anisotropic sand beds bearing structures such as caisson type breakwaters. In particular, effect of fabric anisotropy on bearing capacity was examined in detail. Based on the experimental results in which the shape of plastic wedge zone of anisotropic ground at the peak of bearing capacity was strongly depending on the initial sand deposition condition, an evaluation method for the bearing capacity was also proposed according to the upper bound solution in the limit analysis.
  • KAWAMURA Shima, MIURA Seiichi, ISHIKAWA Tatsuya, YOKOHAMA Shoji
    Doboku Gakkai Ronbunshuu C 公益社団法人 土木学会 66 (3) 577 - 594 1880-604X 2010 [Not refereed][Not invited]
     
      Collapse of slope formed from volcanic soils has been frequently caused in Hokkaido, Japan. This study aims at clarifying failure mechanism of volcanic slope caused by both rainfall and freeze-thaw action. In particular, the effects of freeze-thaw action, slope angle, density and friction of impermeable layer in the slope on mechanical behavior were detailedly investigated on volcanic slopes having several shapes. The results showed that; surface slope failure depends strongly on slope angle, the friction characteristics of impermeable layer and rainfall intensity, and the formation of frozen layer in spring season and the softening of slope by freeze-thaw action in summer season are important for evaluating the stability of volcanic slope.
  • Masahiko YAMAKI, Seiichi MIURA, Shoji YOKOHAMA
    Doboku Gakkai Ronbunshuu C 65 (1) 321 - 333 1880-604X 2009 [Not refereed][Not invited]
  • 山木 正彦, 三浦 清一, 横浜 勝司
    土木学会論文集C（CD-ROM） 65 (1) 321 - 333 1880-604X 2009 [Not refereed][Not invited]
  • S. Takimoto, S. Miura, S. Kawamura, S. Yokohama
    PREDICTION AND SIMULATION METHODS FOR GEOHAZARD MITIGATION 17 - + 2009 [Refereed][Not invited]
     
    This paper presents the fundamentals of mechanical behavior of anisotropic sand beds subjected to wave-structure interactions. A series of model tests was conducted in 1 g field, and the stress conditions in the prototype were replicated by means of both the cyclic loading system and the oscillating water pressure loading system. Similarly, the feature of failure of caisson-breakwaters in Japan due to ocean wave loadings was investigated in detail. Based on the experimental results in which the shape of plastic wedge zone of anisotropic ground at the peak of bearing capacity was strongly depending on the initial sand deposition condition, an evaluation method for the bearing capacity was proposed according to the upper bound solution in the limit analysis.
  • 川村 志麻, 三浦 清一, 横浜 勝司
    土木学会論文集C（CD-ROM） 土木学会 63 (1) 81 - 92 1880-604X 2007 [Not refereed][Not invited]
     
    繰返し力を受ける異方性砂地盤の変形特性を調べるために，二次元平面ひずみ模型土槽と種々の荷重を載荷可能な装置を用いた一連の実験が行われた．得られた結果から，構造物に正弦波的な繰返し力が作用し，ロッキングを生じるような場合では，繰返し力によって変化する最大主応力方向αと地盤の堆積方向βとのなす角ψ(=|β－α|)がある値(本試験の豊浦砂では約40°)に最も近い堆積方向に，構造物は沈下－傾斜することが明らかにされている．また，繰返しに伴う変形の卓越方向を支配する要因が詳細に検討されている．
  • 横浜 勝司, 三浦 清一, 中野 文裕
    土木学会海岸工学論文集 Japan Society of Civil Engineers 53 881 - 885 0916-7897 2006 [Not refereed][Not invited]
     
    様々な大きさの波浪荷重を長期間支える海洋構造物の基礎地盤には, 常に波カー構造物一地盤の動的相互作用による繰返しせん断応力が伝播している. 伝播した応力によって地盤内にはダイレイタンシーに伴う堆積構造や剛性の変化が誘発される. その結果, 構造物・地盤系の安定性が低下する可能性がある. 本研究では構造物下部の砂地盤の変形挙動を合理的に評価することを目的に, 排水条件での要素試験を実施して繰返しせん断を受ける砂のせん断剛性率の変化を調べた. さらに, 一連の試験で得られた剛性変化挙動を反映させた変形解析を実施しその有効性を検討している.
  • T. Ishikawa, S. Miura, S. Yokohama, R. G. Mijares
    Geomechanics and Geotechnics of Particulate Media 121 - 126 2006 [Not refereed][Not invited]
     
    The objective of this study is to evaluate the effect of degree of saturation on the strength characteristics of volcanic coarse-grained soils, wherein particle breakage significantly takes place during loading and deformation processes, under various degrees of saturation conditions. In this paper, a series of monotonic triaxial compression tests for two kinds of volcanic coarse-grained soils are performed under various degrees of saturation conditions, and the relationships between degree of saturation, degree of particle breakage and strength are examined based on experimental results. As the result, the following conclusions are obtained: The shear strength of crushable coarse-grained volcanic soils decreases with an increase in the amount of particle breakage. Particle breakage is strongly influenced by the degree of saturation of the soil matrix. Accordingly, as the crushable volcanic coarse-grained soil becomes saturated, particle breakage becomes more dominant, thereby decreasing the shear strength of the soil.
  • S. Dashdorj, S. Miura, S. Yokohama, K. Masumura
    Numerical Methods in Geotechnical Engineering 759 - 764 2006 [Refereed][Not invited]
     
    In order to reduce a weight of embankment constructed on soft ground air foamed lightweight material has been developed in Japan. The material was applied for bridge abutment backfill and abutment-backfill system behavior is investigated in this research. Reduction of displacement and lateral backfill pressure by placing of elastic plates in FCB backfill is examined by FE analysis. Results from FE analysis revealed that placing of elastic plates in a backfill is effective to reduce the lateral backfill pressure.
  • 横浜 勝司, 三浦 清一, 川村 志麻, 呉 哲浩
    『海岸工学論文集』 Japan Society of Civil Engineers 52 (2) 841 - 845 0916-7897 2005 [Not refereed][Not invited]
     
    波浪による被害を最小限にするために, 防波構造物や港湾施設の防波性能は常に保持される必要がある. そのためには, 波浪に対する構造物の耐久性だけでなく支持地盤の安定性を検討することが必須となる. 本研究では波浪のような繰返し荷重によって変化する砂のせん断特性を考慮した解析法を提案している. 構造物直下の地盤を対象とした繰返し三軸試験では, 繰返し載荷によって発生した砂のひずみが0.1%未満で砂のせん断剛性率が急減することが示された. 要素試験で見られた砂の剛性低下挙動を考慮した繰返し力を受ける構造物・地盤系の変形解析が進められた. 特に3次元および2次元平面ひずみ条件での解析を行い, 解析の次元の違いが支持地盤の変形評価に及ぼす影響が明示された.
  • 横浜 勝司, 三浦 清一
    『土木学会海岸工学論文集』 Japan Society of Civil Engineers Vol.51 831 - 835 0916-7897 2004 [Not refereed][Not invited]
     
    半永久的な繰返し波浪を受ける海洋構造物・地盤系では, 動的相互作用や地盤内の間隙水圧挙動によって沈下等の変形が進行的に発生する. このような変形挙動は構造物・地盤系の安定性低下の一因となる. これらの構造物の合理的な維持・管理のためには, 支持地盤も含めた全体系の安定性評価法を見出すことが必要とされる. 本研究では, ベンダーエレメントを設置した非排水繰返し三軸試験機による要素試験を実施し, 繰返しせん断中の砂のせん断剛性率を測定した. 一連の要素試験より得られた結果を考慮した構造物・地盤系の変形解析法を提案した. 本解析法によって構造物の沈下性状や地盤内の側方変形挙動を良く評価できることが示されている.
  • 三浦 清一, 川村 志麻, 横浜 勝司
    『土木学会海岸工学論文集』 土木学会 Vol.51 811 - 815 0916-7897 2004 [Not refereed][Not invited]
     
    海洋構造物を支持する砂地盤の流動現象を評価するために, 波浪のような荷重を再現した一連の模型実験を行った. 本研究では, 今までに明らかにした構造物支持地盤の強度-変形が地盤の堆積構造 (構造異方性) に強く依存するという事実に基づき, 海洋構造物を支持する異方性地盤の流動変形のメカニズムとその沈下・流動方向を決定する要因を明らかにし, 側方流動変形の卓越方向推定のための方法を検討した. その結果, 原地盤のサンプリング情報等に基づいて地盤の堆積方向βを決定し, 波浪条件 (偏心度など) から支持地盤内に生じる最大主応力方向αを算出すれば, 海底砂地盤の流動方向の推定が可能になる等の事実が示されている.
  • 三浦 清一, 石川 達也, 横濱 勝司
    土と基礎 社団法人地盤工学会 51 (12) 77 - 81 0041-3798 2003/12/01 [Not refereed][Not invited]
  • S Yokohama, S Miura, S Kawamura
    DEFORMATION CHARACTERISTICS OF GEOMATERIALS 809 - 815 2003 [Not refereed][Not invited]
     
    In order to clarify the deformation behavior of structure-sand ground system subjected to cyclic loadings such as wave force, a series of FE analysis based on Mohr-Coulomb criteria with non-associated flow rule, together with 1 g model tests were carried out under various loading conditions. In the model test, characteristics of elastic modulus of sand deposits were investigated in detail and were quantified. It is observed that the stiffness of sand deposits changes with increasing of the settlement of structure. Softening behavior of sand deposits suddenly occurs if lateral flow deformation due to cyclic loading exceeds a limit. Based on such behavior, a new analytical technique in use for predicting deformation of structure-ground was proposed. The analytical results can explain well the lateral deformation of sand ground-structure system under various loading conditions.
  • S Kawamura, S Miura, S Yokohama
    DEFORMATION CHARACTERISTICS OF GEOMATERIALS 1303 - 1310 2003 [Not refereed][Not invited]
     
    The present study aims at clarifying mechanical behavior of anisotropic ground beneath structure subjected to cyclic loading or monotonic loading. In particular, effect of fabric anisotropy on lateral flow deformation behavior of sand ground in static and cyclic fields was clarified, and the importance of evaluation of lateral deformation for anisotropic grounds was also indicated.
  • 横浜 勝司, 三浦 清一, 林 秀人
    『海岸工学論文集』 Japan Society of Civil Engineers Vol.50 876 - 880 0916-7897 2003 [Not refereed][Not invited]
     
    波浪等の厳しい外力条件下にある海洋構造物は荷重を繰返し受けて振動している. この状況では構造物と支持地盤との動的相互作用によって下部地盤には側方流動型の大変形が発生し構造物・地盤系の安定性が低下することが考えられる. このような繰返し載荷が構造物・地盤系の安定性低下に及ぼす影響は大きく, その評価法を見出すことは極めて重要である. 本研究では, 一連の模型試験及び数値解析を行い構造物の沈下や傾斜に伴う支持砂地盤の変形挙動を評価する手法を検討している. 特に砂の剛性変化および強度変化を考慮した解析モデルを組込んだ解析法を提案した. 解析結果と模型試験による実測値を比較することで本解析法の適用性を検討した.
  • YOKOHAMA Shoji, MIURA Seiichi, KAWAMURA Shima
    Doboku Gakkai Ronbunshu 土木学会 (715) 263 - 275 0289-7806 2002/09/21 [Not refereed][Not invited]
     
    波浪のような繰返し荷重を受ける構造物・地盤系の安定性評価法確立のために必要な, 地盤の流動変形を考慮した構造物の変位量の推定法を明らかにすることを目的に, 二次元平面ひずみ模型土槽装置を用いた一連の実験と解析を行った. 本研究では, 特に構造物の沈下挙動と地盤の側方流動変形挙動を詳細に調べている. 具体的には, 静的及び繰返し荷重場にある地盤の側方流動挙動をFEM解析によって検討し, 任意荷重場の地盤・構造物系の変形挙動を再現できるような解析法を検討している. また, 解析から得た側方流動変形挙動を考慮した構造物変位量の推定式を提案した. 推定式は, 構造物天端2地点で計測された鉛直変位量から繰返し荷重場にある構造物の変位量を精度良く推定することが示されている.
  • 横浜 勝司, 三浦 清一, 川村 志麻
    『土木学会論文集』 土木学会 (No.715/III-60) ,pp.263-275 - 275 0289-7806 2002 [Not refereed][Not invited]
     
    波浪のような繰返し荷重を受ける構造物・地盤系の安定性評価法確立のために必要な, 地盤の流動変形を考慮した構造物の変位量の推定法を明らかにすることを目的に, 二次元平面ひずみ模型土槽装置を用いた一連の実験と解析を行った. 本研究では, 特に構造物の沈下挙動と地盤の側方流動変形挙動を詳細に調べている. 具体的には, 静的及び繰返し荷重場にある地盤の側方流動挙動をFEM解析によって検討し, 任意荷重場の地盤・構造物系の変形挙動を再現できるような解析法を検討している. また, 解析から得た側方流動変形挙動を考慮した構造物変位量の推定式を提案した. 推定式は, 構造物天端2地点で計測された鉛直変位量から繰返し荷重場にある構造物の変位量を精度良く推定することが示されている.
  • 横浜 勝司, 三浦 清一
    『応用力学論文集』 土木学会 Vol.5 473 - 480 1345-9139 2002 [Not refereed][Not invited]
  • 横浜 勝司, 三浦 清一, 林 秀人
    『海岸工学論文集』 Japan Society of Civil Engineers Vol.49 851 - 855 0916-7897 2002 [Not refereed][Not invited]
     
    波浪場にある構造物・地盤系では, 外力-構造物-地盤の動的相互作用によって基礎地盤の支持力低下や側方流動型の大変形が誘発される現象が見られる. したがって, 繰返し荷重を受ける構造物・地盤系の安定性を管理するために, 地盤内の側方流動特性を把握することが重要となる. 本研究では一連の有限要素解析および模型試験を行い, 繰返し載荷場での構造物支持地盤の剛性変化特性を調べた. さらに地盤の剛性変化特性を考慮した変形解析法を提案した. 提案法は波浪のような繰返し力を受ける地盤の流動変形を評価するために有効であることが示された.
  • MIYAURA Masahiro, MIURA Seiichi, KAWAMURA Shima, YOKOHAMA Shoji
    Doboku Gakkai Ronbunshu 土木学会 673 (673) 121 - 131 0289-7806 2001/03/21 [Not refereed][Not invited]
     
    In order to clarify bearing capacity of a structure-sand ground system subjected to various types of loading, a series of model tests were carried out under several static and cyclic loading conditions. It was found that; (1) lateral flow behavior of the ground depends strongly on the settlement performance of a structure, (2) bearing capacity of the ground can be evaluated by a failure envelope which is depicted in M-V-H plane irrespective of the difference in loading conditions, and (3) stability of the sand ground-structure system may be evalutated by using the parameter Vδ/Vρ which is adopted as the measure of lateral deformation volume in this study.
  • 「構造物支持地盤の側方変形特性に及ぼす諸要因の影響」
    『第46回地盤工学シンポジウム論文集』 Vol.46 173 - 180 2001 [Not refereed][Not invited]
  • MIYAURA Masahiro, MIURA Seiichi, KAWAMURA Shima, YOKOHAMA Shoji
    Doboku Gakkai Ronbunshu 土木学会 673 (673) 121 - 131 0289-7806 2001 [Not refereed][Not invited]
     
    In order to clarify bearing capacity of a structure-sand ground system subjected to various types of loading, a series of model tests were carried out under several static and cyclic loading conditions. It was found that; (1) lateral flow behavior of the ground depends strongly on the settlement performance of a structure, (2) bearing capacity of the ground can be evaluated by a failure envelope which is depicted in M-V-H plane irrespective of the difference in loading conditions, and (3) stability of the sand ground-structure system may be evalutated by using the parameter Vδ/Vρ which is adopted as the measure of lateral deformation volume in this study.
  • 「波浪力を受ける海洋構造物支持地盤の異方性を考慮した側方流動変形の推定法に関する研究」
    『海岸工学論文集』 Vol.48 986 - 990 2001 [Not refereed][Not invited]
  • 『応用力学論文集』 Vol.4 397 - 404 2001 [Not refereed][Not invited]
  • 「波浪場にある海洋構造物－地盤系の支持力安定性を支配する要因とその評価法」
    『海岸工学論文集』 Vol.48 1011 - 1015 2001 [Not refereed][Not invited]
  • 三浦 清一, 川村 志麻, 柴田 泰孝, 横浜 勝司
    海岸工学論文集 Japan Society of Civil Engineers 48 986 - 990 0916-7897 2001
  • 川村 志麻, 三浦 清一, 横浜 勝司
    海岸工学論文集 土木学会 48 1011 - 1015 0916-7897 2001
  • 横浜 勝司, 三浦 清一, 川村 志麻, 宮浦 征宏
    土木学会海岸工学論文集 土木学会 47 936 - 940 0916-7897 2000 [Not refereed][Not invited]
  • 土木学会応用力学論文集 3 513 - 520 2000 [Not refereed][Not invited]
  • Mechanical behavior of sand bed-coastal system subjected to cyclic loading
    Proc., International Conference on Geotechnical and Geological Engineering 500  2000 [Not refereed][Not invited]
  • KAWAMURA Shima, MIURA Seiichi, YOKOHAMA Shoji, MIYAURA Masahiro
    Doboku Gakkai Ronbunshu 土木学会 (624) 77 - 89 0289-7806 1999/06/21 [Not refereed][Not invited]
     
    波浪のような繰返し力を受ける構造物支持地盤の破壊機構とその防止策について, 種々の繰返し力を載荷可能な装置と二次元平面ひずみ試験土槽装置を用いて一連の実験を行い, 次のような結果を得た. 1) 波浪場にある地盤-構造物系の破壊は変形が徐々に進行するような側方流動型破壊を示す, 2) このような地盤破壊の防止策として, 構造物底部に側壁を設ける方法や地盤内に矢板を設置するような対策法は, 側方流動型の破壊阻止に一定の効果が期待できるが, その効果はそれらの形状及び設置条件によってかなり異なる. 本論文では, このような側方流動型破壊の基本的な阻止機構について詳細な検討が加えられている.
  • KAWAMURA Shima, MIURA Seiichi, YOKOHAMA Shoji, MIYAURA Masahiro
    Doboku Gakkai Ronbunshu 土木学会 (624) 65 - 75 0289-7806 1999/06/21 [Not refereed][Not invited]
     
    波浪のような繰返し力を受ける構造物支持地盤の動的力学挙動を調べるために, 外力の作用方向の異なる基本的な実験が二次元平面ひずみ土槽装置と種々の繰返し力を載荷可能な装置を用いて行われた. 一連の実験と解析から, 1) 波浪と構造物の相互作用によって誘発される構造物直下のせん断応力は地盤深さによってその大きさは変化するものの, 完全両振りの条件にある, 2) 波浪のような外力を鉛直及び水平方向に分担させた試験では, 通常の室内繰返しせん断試験と同様な結果の整理が可能である, 3) このような繰返し力を受ける構造物支持地盤の動的力学挙動を評価するには, せん断応力と外力の作用方向の適確な把握が極めて重要である, などの事実が示されている.
  • 宮浦 征宏, 三浦 清一, 横浜 勝司, 川村 志麻
    土木学会海岸工学論文集 土木学会 46 936 - 940 0916-7897 1999 [Not refereed][Not invited]
  • Mechanical behaviors of sand bed-structure system subjected to cyclic loadings
    Proc., 11th Asian regional conference on Soil Mechanics and Geotechnical Engineering 161  1999 [Not refereed][Not invited]
  • 川村志麻, 三浦清一, 横浜勝司, 宮浦征宏
    土木学会論文集 土木学会 (624) 77 - 89 0289-7806 1999 [Not refereed][Not invited]
     
    波浪のような繰返し力を受ける構造物支持地盤の破壊機構とその防止策について, 種々の繰返し力を載荷可能な装置と二次元平面ひずみ試験土槽装置を用いて一連の実験を行い, 次のような結果を得た. 1) 波浪場にある地盤-構造物系の破壊は変形が徐々に進行するような側方流動型破壊を示す, 2) このような地盤破壊の防止策として, 構造物底部に側壁を設ける方法や地盤内に矢板を設置するような対策法は, 側方流動型の破壊阻止に一定の効果が期待できるが, その効果はそれらの形状及び設置条件によってかなり異なる. 本論文では, このような側方流動型破壊の基本的な阻止機構について詳細な検討が加えられている.
  • 川村志麻, 三浦清一, 横浜勝司, 宮浦征宏
    土木学会論文集 土木学会 (624) 65 - 75 0289-7806 1999 [Not refereed][Not invited]
     
    波浪のような繰返し力を受ける構造物支持地盤の動的力学挙動を調べるために, 外力の作用方向の異なる基本的な実験が二次元平面ひずみ土槽装置と種々の繰返し力を載荷可能な装置を用いて行われた. 一連の実験と解析から, 1) 波浪と構造物の相互作用によって誘発される構造物直下のせん断応力は地盤深さによってその大きさは変化するものの, 完全両振りの条件にある, 2) 波浪のような外力を鉛直及び水平方向に分担させた試験では, 通常の室内繰返しせん断試験と同様な結果の整理が可能である, 3) このような繰返し力を受ける構造物支持地盤の動的力学挙動を評価するには, せん断応力と外力の作用方向の適確な把握が極めて重要である, などの事実が示されている.
  • S Miura, S Kawamura, S Yokohama, M Miyaura
    EARTHQUAKE GEOTECHNICAL ENGINEERING, VOLS 1-3 321 - 326 1999 [Refereed][Not invited]
     
    The present study aims to clarify the mechanical response of sand bed bearing coastal structures such as wave dissipating blocks and breakwaters to ocean wave. A series of cyclic loading tests and model tests were performed on a model structure under several loading conditions induced by wave forces. In the model tests, field conditions are simulated by using the cyclic loading systems, the oscillating water pressure loading system and the two dimensional plane strain soil box, which are developed in this study. It was found that 1) the reproductions of (1)perfectly reversal condition of cyclic shear stress induced in sand deposits and (2)oscillating water pressure effects are very important in the model tests to see the mechanical response of seabed-structure system, 2) the failure modes of ground depend strongly on the magnitude and direction of wave forces, and 3) the ground failure is produced not only by initial liquefaction but also by lateral flow slide.
  • 三浦 清一, 横浜 勝司, 川村 志麻, 宮浦 征宏
    土木学会海岸工学論文集 土木学会 45 876 - 880 0916-7897 1998 [Not refereed][Not invited]
  • S Kawamura, S Miura, S Yokohama, Y Hagihara
    DEFORMATION AND PROGRESSIVE FAILURE IN GEOMECHANICS - IS-NAGOYA'97 571 - 576 1997 [Refereed][Not invited]
     
    The deformation behavior of seabed bearing coastal structures subjected to wave force was investigated using a model soil box with a two-dimensional plane strain condition. A series of cyclic loading tests were performed on model dissipating structures under loading conditions which simulate several loads such as that of an ocean wave. It was found that the progressive flow failure of the seabed bearing a man-made structure was not induced by initial liquefaction but by lateral flow slide, and the installation of side wall such as sheet pile in the sand leads to noticeably reduce the settlement and lateral flow deformation of seabed. Furthermore, a prediction method of the settlement and horizontal displacement of a structure due to cyclic loading was developed based on the test results.

Conference Activities & Talks

  • Cyclic mechanical properties of sandy soils by mixing recycled asphalt pavement material  [Not invited]
    YOKOHAMA Shoji, SATO Astuko
    8th international conference on Geotechnique, Construction Material and Environment (GEOMATE2018)  2018/11

Works

  • 平成20年(2008年)岩手・宮城内陸地震現地調査
    2008
  • 平成19年(2007年)新潟県中越沖地震現地調査
    2007

MISC

  • 横浜勝司  地盤工学会北海道支部技術報告集(CD-ROM)  (60)  2020
  • 横浜勝司  土木学会年次学術講演会講演概要集(CD-ROM)  75th-  2020
  • 横浜勝司  地盤工学研究発表会発表講演集(Web)  55th-  2020
  • 横浜勝司  地盤工学研究発表会発表講演集(Web)  54th-  2019
  • 横浜勝司, 佐藤厚子  地盤工学研究発表会発表講演集(CD-ROM)  53rd-  2018
  • 横浜勝司, 佐藤厚子  地盤工学会北海道支部技術報告集(CD-ROM)  (57)  2017
  • 横浜勝司, 佐藤厚子  地盤工学研究発表会発表講演集(CD-ROM)  52nd-  2017
  • 横浜勝司, 佐藤厚子  地盤工学会北海道支部技術報告集(CD-ROM)  (56)  2016
  • 佐藤厚子, 林憲裕, 横浜勝司  地盤工学会北海道支部技術報告集(CD-ROM)  (56)  2016
  • 佐藤厚子, 林憲裕, 横浜勝司  地盤工学研究発表会発表講演集(CD-ROM)  51st-  2016
  • 横浜勝司, 佐藤厚子  地盤工学研究発表会発表講演集(CD-ROM)  51st-  2016
  • 横浜勝司, 福島宏文  地盤工学会北海道支部技術報告集(CD-ROM)  (55)  2015
  • 横浜勝司, 福島宏文  地盤工学研究発表会発表講演集(CD-ROM)  50th-  2015
  • 松村聡, 三浦清一, 横浜勝司  地盤工学研究発表会発表講演集(CD-ROM)  49th-  2014
  • NAKAMURA Hirotake, YOKOTA Seiya, FUJIOKA Kazuyori, YOKOHAMA Shoji, MIURA Seiichi  Doboku Gakkai Ronbunshuu C  70-  (1)  125  -134  2014  [Not refereed][Not invited]
     
    High embankment in Shin-Tomei-expressway was built in the Asitaka Loam. This embankment has height of 55 meters. In this site, the significant settlement was concerned over the long term after finishing construction the embankment. This paper shows the data about the settlement obtained by long term observation and laboratory tests. Based on those data, we tried that we evaluated the settlement of construction and future of the high embankment using Ashitaka loam. As a result, it was found that the settlement of embankment under construction produced around 5-9%, the laboratory test had a small settlements for that we calculated from an actual value, the observation during construction at the short span became large settlements, and the residual settlement of around 100cm may occur ten years after the number.
  • MATSUMURA Satoshi, MIURA Seiichi, YOKOHAMA Shoji  Doboku Gakkai Ronbunshuu C  70-  (2)  238  -247  2014  [Not refereed][Not invited]
     
    It is important to reveal mechanical characteristics of compacted soils in order to ensure stable performance for embankments. However, there may be few experimental studies to verify cyclic shear behavior of embankments. Furthermore, the evaluation of liquefaction potential of embankments has been recently pointed out as well as that of foundation below embankments.<br> On the other hand, in Hokkaido, where many kinds of volcanic soils widely deposit, those soils have been often employed as embankment materials. According to previous researches, coarse-grained volcanic soils have some features of fragility and inner-porosity to cause particle breakage which influence the mechanical characteristics of those soils.<br> In this study, for the purpose to evaluate the influential factors on the cyclic shear behavior of embankments, a series of cyclic undrained triaxial tests was carried out on compacted samples using a coarse-grained volcanic soil deposited in Hokkaido. Each triaxial specimen was made in a different condition based on water content at compaction, dry density and finer content. Experimental results show that compaction conditions such as water content and dry density can affect cyclic strength of compacted soils. However, the tendency to cyclic strength may be quite different depending on the difference of finer content.
  • 横浜 勝司  地盤工学会誌  62-  (3)  60  -61  2014  [Not refereed][Not invited]
  • 川村志麻, 五十嵐はるか, 三浦清一, 石川達也, 横浜勝司  土木学会年次学術講演会講演概要集(CD-ROM)  65th-  2010
  • KAWAMURA Shima, MIURA Seiichi, ISHIKAWA Tatsuya, YOKOHAMA Shoji  Journal of Japan Society of Civil Engineers, Ser. C (Geosphere Engineering)  66-  (3)  577  -594  2010  [Not refereed][Not invited]
     
    Collapse of slope formed from volcanic soils has been frequently caused in Hokkaido, Japan. This study aims at clarifying failure mechanism of volcanic slope caused by both rainfall and freeze-thaw action. In particular, the effects of freeze-thaw action, slope angle, density and friction of impermeable layer in the slope on mechanical behavior were detailedly investigated on volcanic slopes having several shapes. The results showed that; surface slope failure depends strongly on slope angle, the friction characteristics of impermeable layer and rainfall intensity, and the formation of frozen layer in spring season and the softening of slope by freeze-thaw action in summer season are important for evaluating the stability of volcanic slope.
  • 横浜 勝司  地盤工学会誌  56-  (12)  29  -29  2008/12/01  [Not refereed][Not invited]
  • 石川 達也, 三浦 清一, 横浜 勝司, 川村 志麻  土木学会年次学術講演会講演概要集  62-  (3)  27  -28  2007/09
  • 井野 寿人, 川村 志麻, 木幡 行宏, 三浦 清一, 石川 達也, 横浜 勝司  土木学会年次学術講演会講演概要集  62-  (3)  13  -14  2007/09
  • KAWAMURA Shima, MIURA Seiichi, YOKOHAMA Shoji  Journal of Japan Society of Civil Engineers, Ser. C (Geosphere Engineering)  63-  (1)  81  -92  2007  [Not refereed][Not invited]
     
    The present study aims at revealing mechanical behavior of anisotropic ground beneath a structure subjected to cyclic loading. In particular, effect of fabric anisotropy on cyclic strength-lateral flow deformation behavior was investigated by using the soil box apparatus. For example, dependence of fabric anisotropy of the ground on deformation direction was evaluated quantitatively. Test results showed that deformation direction in the ground-structure system depended strongly on the depositional condition of the ground and developed in the direction of bedding plane where the relative angle δ=45°-φ/2-ψ became the smallest in the ground.
  • 川村 志麻, 三浦 清一, 横浜 勝司  土木学会論文集C  63-  (1)  81  -92  2007  [Not refereed][Not invited]
     
    繰返し力を受ける異方性砂地盤の変形特性を調べるために，二次元平面ひずみ模型土槽と種々の荷重を載荷可能な装置を用いた一連の実験が行われた．得られた結果から，構造物に正弦波的な繰返し力が作用し，ロッキングを生じるような場合では，繰返し力によって変化する最大主応力方向αと地盤の堆積方向βとのなす角ψ(=|β－α|)がある値(本試験の豊浦砂では約40°)に最も近い堆積方向に，構造物は沈下－傾斜することが明らかにされている．また，繰返しに伴う変形の卓越方向を支配する要因が詳細に検討されている．
  • 山木正彦, 所哲也, 三浦清一, 石川達也, 横浜勝司  地盤工学会北海道支部技術報告集  (46)  2006
  • 横浜 勝司  土と基礎  53-  (12)  71  -72  2005/12/01  [Not refereed][Not invited]
  • 横浜勝司, 三浦清一, 石川達也  地盤工学研究発表会発表講演集  40th-  2005
  • S Yokohama, S Miura, S Kawamura, S Dashdorj  PROCEEDINGS OF THE FIFTEENTH (2005) INTERNATIONAL OFFSHORE AND POLAR ENGINEERING CONFERENCE, VOL 2  371  -376  2005  [Not refereed][Not invited]
     
    Deformation behavior of a structure-ground system is evaluated using a series of numerical analyses and laboratory tests. In order to investigate the change in rigidity of sand, a triaxial tests apparatus with bender element was used to evaluate shear modulus of sand specimens. An analysis technique is proposed with consideration of rigidity reduction, based on the results of laboratory tests. Using the proposed method, behavior of settlement and lateral deformation of the structure-ground system are well simulated. Analyzed lateral displacement of the structure-ground system is compared to the laboratory data obtained by the model test.
  • Yokohama Shoji, Miura Seiichi, Mishima Hidemasa  Proceedings of the Japan National Conference on Geotechnical Engineering  39-  (0)  1417  -1418  2004  [Not refereed][Not invited]
     
    It is important to investigate the deformation behavior of ground in order to evaluate the stability of coastal structure-ground system. Rigidity variation of ground under cyclic loading condition should be revealed for the deformation analysis. In present study, the effect of excess pore water pressure on rigidity variation of sand at the large strain region is clarified by bender element test. Deformation analysis based on the results of bender element test can explain deformation of structure-ground system under cyclic loading.
  • Dashdorj Sarandulam, Miura Seiichi, Yokohama Shoji  Proceedings of the Japan National Conference on Geotechnical Engineering  39-  (0)  745  -746  2004  [Not refereed][Not invited]
     
    As one of the methods to reduce lateral earth pressure on bridge abutment specially constructed in soft ground, lightweight geomaterial have been used for back-filling of bridge abutment. In this study, FEM analysis was carried out to evaluate a reduction of lateral earth pressure and the deformation of lightweight backfill acting behind the bridge abutment. Through the analysis, field measured data of the bridge backfilled with lightweight geomaterial was compared to the analyzed data. It was revealed that the earth pressure of backfill was reduced when the backfill was placed by lightweight geomaterial although the deformation had been still occured.
  • 2003年十勝沖地震地盤災害調査報告書
    『地盤工学会2003年十勝沖地震地盤災害調査委員会』  2004  [Not refereed][Not invited]
  • Yokohama Shoji, Miura Seiichi, Mishima Hidemasa, Hayashi Hideto  Proceedings of the Japan National Conference on Geotechnical Engineering  38-  (0)  447  -448  2003  [Not refereed][Not invited]
     
    It is necessary for design of ground-structure system that mechanism of lateral flow deformation behavior under cyclic loading condition can be evaluated by simple analysis technique. In this study, a series of FE analysis based on Mohr-Coulomb criteria with non-associated flow rule was preformed. In order to accurately simulate the deformation of ground, a simple relationship between internal friction angle of sand and shear strain is assumed. Analysis technique with considering change in elastic modulus and strength is developed. It is shown that this method may be useful for analysis on lateral flow deformation under cyclic loading conditions.
  • Dashdorj Sarandulam, Miura Seiichi, Yokohama Shoji  Proceedings of the Japan National Conference on Geotechnical Engineering  38-  (0)  825  -826  2003  [Not refereed][Not invited]
     
    Lightweight geomaterials have been developed and utilized recently for the construction of embankments and earth structures where it is not suitable to use ordinary soil. In this study static and cyclic mechanical behavior of air foamed lightweight geomaterial was investigated. Series of unconfined compression and cyclic triaxial tests were carried out by using 28 days-curing specimens. It was confirmed that the unconfined compression strength and Young′s modulus of the material could be controlled by adjusting dry density, moisture content and curing temperature. Based on the test results, correlation between cyclic shear modulus and unconfined compression strength was predicted.
  • S Yokohama, S Miura  PROCEEDINGS OF THE THIRTEENTH (2003) INTERNATIONAL OFFSHORE AND POLAR ENGINEERING CONFERENCE, VOL 1  61  -67  2003  [Not refereed][Not invited]
     
    Settlement analysis of an offshore structure attributed to lateral flow deformation of ground beneath the structure has been conducted. It is desired for coastal engineering design that deformation behavior of structure-ground system can be assessed by simple method such as finite element analysis. In order to reveal the mechanical behavior of sand ground which supports a structure subjected to various cyclic loads, a series of model tests and elasto-plastic FE analysis were carried out. In this study, one conventional technique for the deformation analysis for structure-sand deposits system is proposed.
  • Yokohama Shoji, Miura Seiichi, Hayashi Hideto  Proceedings of the Japan National Conference on Geotechnical Engineering  37-  (0)  515  -516  2002  [Not refereed][Not invited]
  • Yokohama S, Miura S, Kawamura S  Journal of Environmental Science Laboratory  8-  (0)  373  -381  2001/12/30  [Not refereed][Not invited]
     
    In order to analytically mechanical behavior of sand-ground system under cyclic vertical central or eccentric loading condition, a series of FEM analyses and model tests were performed. From the model test, it was observed that the sand deposits beneath a structure subjected to static or cyclic loadings deform laterally with increasing of the settlement of structure. In addition, the characteristics of ground deformation vary from hardening to softening behavior, in particular, under the cyclic condition. Based on the test results, a technique of analysis for lateral deformation based on th...
  • Lateral flow deformation evaluation of ground-structure system under various cyclic loading conditions
    Proceedings of Fourth International Conference on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics (CD-ROM)  628  2001  [Not refereed][Not invited]
  • An Evaluation Method for Stability of Coastal Structure-Ground System subjected to Wave Force
    Proceedings of International Conference on Engineering for Ocean and Offshore Structure and Coastal Engineering Development  78  -85  2001  [Not refereed][Not invited]
  • YOKOHAMA Shoji, KAWAMURA Shima, MIURA Seiichi  Doboku Gakkai Ronbunshuu A  3-  513  -520  2000  [Not refereed][Not invited]
     
    This study aims to clarify analytically mechanical behaviors of a sand-structure system subjected to static and cyclic loadings.In particular, the settlement-lateral deformation behaviors of the ground bearing a structure are focused.A series of FEM analysis based on Mohr-Coulomb formulas with non-associated flow rule was carried out to accomplish the purpose.The analysis results obtained were detailedly compared with those of the model static and cyclic tests performed on the two-dimensional soil box.On the basis of these results, the applicability of FEM analysis to evaluate the deformation behaviors of the ground-structure system was made clear.
  • 横浜 勝司, 川村 志麻, 三浦 清一  環境科学研究所報告  (7)  187  -195  2000  [Not refereed][Not invited]
  • 三浦 清一, 横浜 勝司, 川村 志麻, 田中 則男  海岸工学論文集  44-  921  -925  1997  [Not refereed][Not invited]
  • 川村 志麻, 三浦 清一, 横浜 勝司  海岸工学論文集  44-  936  -940  1997  [Not refereed][Not invited]
  • 川村 志麻, 三浦 清一, 横浜 勝司  海岸工学論文集  44-  936  -940  1997  [Not refereed][Not invited]

Awards & Honors

  • 2012/11 International conference on Ground Improvement and Ground Control (ICGI2012) Best Paper Award
     Bearing capacity improvement of anisotropic sand ground and its evaluation 
    受賞者: KAWAMURA Shima;MIURA Seiichi;YOKOHAMA Shoji
  • 2006 地盤工学研究発表会優秀論文発表者賞
  • 2002/04 地盤工学会北海道支部 平成13年度地盤工学会北海道支部賞
     繰返し荷重下にある砂地盤の側方流動変形解析法 
    受賞者: 横濱 勝司

Research Grants & Projects

  • 科学研究費補助金（基盤C）
    Date (from‐to) : 2018/04 -2021/03 
    Author : 横濱 勝司
  • Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research
    Date (from‐to) : 2011/04 -2014/03 
    Author : MIURA SEIICHI, ISHIKAWA Tatsuya, KAWAMURA Shima, YOKOHAMA Shoji
     
    The aim of this study is to reveal the failure mechanism of volcanic slopes in cold regions and to propose a prediction method on failure. To achieve the purposes, full-scale embankments were constructed under several conditions in Sapporo, Japan. A typical volcanic soil in the field was adopted as a soil material. After construction of embankments, changes in soil moisture, temperature, pore water pressure were investigated using devices such as soil moisture meters, etc. Simultaneously, a series of model tests was performed on small size slopes formed by the same material as that in the field to compare with the mechanical behavior of embankments. A series of triaxial tests was also conducted on compacted volcanic soils subjected to freeze-thaw cycles using a new apparatus. As a result, a reasonable prediction method of failure was proposed based on changes in water content, and its validity was confirmed.
  • Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research
    Date (from‐to) : 2008 -2010 
    Author : ISHIKAWA Tatsuya, MIURA Seiichi, YOKOHAMA Shouji, KAMEYAMA Shuichi, YAMASHITA Satoshi, ONO Takashi, ABE Ryuji, SEKINE Etsuo, HACHIYA Yoshitaka
     
    In this study, we proposed new testing methods for the evaluation of the deformation-strength characteristics of base course materials subjected to freeze-thaw action, and examined the mechanical behavior of granular base before and after freeze-thawing and under freezing. We also evaluated the influences of the change in the performance of granular base due to freeze-thawing on the fatigue breaking of pavements in cold regions by applying the theoretical design method for asphalt pavement. As the result, it was revealed that the freeze-thawing of granular base has a strong influence on the fatigue life of pavement structure in cold regions because it varies the deformation-strength characteristics of base course materials.
  • Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research
    Date (from‐to) : 2008 -2009 
    Author : YOKOHAMA Shoji
     
    In order to investigate characteristics of mechanical behavior of immobilized soil contaminated by lead and hexavalent chromium. In this study, a volcanic product is use as a material of the immobilization of polluted soil. From the test results, it is found that admixture of the volcanic product and polluted soil brings in secure immobilization. On the other hand, it is pointed out that a possibility for strength reduction of immobilized soil by using present technique is exits.
  • Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research
    Date (from‐to) : 2007 -2009 
    Author : MIURA Seiichi, AKAGAWA Satoshi, ISHIKAWA Tatsuya, YOKOHAMA Shoji, KAWAMURA Shima, IWAHANA Go, ITOU Yoshihiko, NISHIMOTO Satoshi
     
    We elucidated the interaction between various factors which caused subsurface failure of volcanic soil ground subjected to freeze-thaw action in cold regions in terms of soil mechanics, and we proposed a new simple prediction method for the rain-induced slope failure in snow-melting seasons in consideration of the degradation of deformation-strength characteristics of geomaterials due to freeze-thawing. We also developed a geo-information database which integrated the various different kinds of information such as weather reports, geotechnical information, and records for past geohazards. Based on these achievements, finally, we developed the system which could evaluate a risk of rain-induced slope failure at subsurface layers suffered from freeze-thaw by using both above-mentioned prediction method and geo-information database.
  • 種々の地盤材料の力学特性に及ぼす締固め条件の違いの影響に関する研究
    Date (from‐to) : 2009
  • Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research
    Date (from‐to) : 2006 -2007 
    Author : ISHIKAWA Tatsuya, MIURA Seiichi, YOKOHAMA Shoji, SEKINE Etsuo
     
    This study examines the mechanical behavior of granular materials under saturated and unsaturated conditions subjected to cyclic moving loads, for example gravel roadbed and railroad ballast, and both a new testing methods and new analytical procedure to examine the effects of the rotation of principal stress axes and water content on cyclic plastic deformation of granular base course materials are proposed. The following conclusions can be obtained; 1. Two types of small scale model tests which adopted a fixed-place loading method and a moving loading method were performed with a base course material under air-dried condition and saturated condition. As the results, it was revealed that the water content of the base course material influences the mechanical behavior of granular base strongly, and the effect on the development of residual settlement for granular base under cyclic loading remarkably comes to the surface in employing moving loads. 2. Two types of multi-ring shear tests, which can consider a change in direction of principal stresses like traffic loads, were performed in the same way as loading methods in small scale model tests. As the results, it was revealed that the shear strength decreased and the cumulative residual strain increased due to the saturation, and that the mechanical behavior in multi-ring shear tests is very similar to that in small scale model tests, regardless of loading methods and water contents. 3. A new method to estimate cyclic plastic deformation of granular base under repeated wheel traveling in terms of the strength and deformation characteristics of granular base course materials was proposed. The simple analytical procedure with linear elastic FE analysis considering the cumulative strain derived from multi-ring shear test results of base course materials can roughly estimate the residual settlement of granular base under saturated and unsaturated conditions subjected to cyclic moving loads.
  • Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research
    Date (from‐to) : 2004 -2006 
    Author : MIURA Seiichi, AKAGAWA Satoshi, ISHIKAWA Tatsuya, YOKOHAMA Shoji, KAWAMURA Shima
     
    Based on the experimental and numerical studies of slope stability of crushable soils, the following conclusions are obtained: 1.Effect of freeze-thaw sequence on static mechanical behavior of volcanic soil (1)Particle breakage of volcanic coarse-grained soil significantly occurs due to the repetition of freeze-thaw sequence. The particle breakage affects strongly on static strength and rigidity of volcanic soil. (2)Volcanic soil subjected to freeze-thaw sequences may produce a remarkable crushability at low confining pressure level. This fact suggests that deterioration in the stability of slope near the surface is significant on snowy cold region. 2.Effect of freeze-thaw sequence on dynamic mechanical behavior of volcanic soil (1)Shear modulus of volcanic coarse-grained soil decreases due to freeze-thaw sequences. On the other hand, freeze-thaw action may less affect hysteresis damping ratio. (2)Liquefaction resistance of volcanic soil decreased due to freeze-thaw sequences. This fact may attribute the reduction of the liquefaction resistance to the increase in finer content induced by particle breakage during freeze-thaw sequences. 3.Rainfall-induced slope collapse for crushable volcanic soil and its evaluation (1)From the results of model tests, it is found that excess pore water pressure and saturation degree play a key role in the slope failure induced by rainfall. (2)Depth and shape of impermeable layer in the slope are critical to estimate the stability of slope. 4.Numerical analysis for rainfall-induced slope failure for crushable volcanic soil (1)A series of numerical analysis by DEM showed that proposed small void elements between soil particles, which are able to expand in accordance with temperature depression, can simulate the mechanical freeze-thaw performance of granular materials. (2)Discontinuous Deformation Analysis (DDA) could explain the slope failure mechanism if rainfall and dilatancy effects on volcanic soil are estimated appropriately into analysis algorithm.
  • 有害重金属を含む地盤の合理的不溶化法と力学特性に関する研究
    Date (from‐to) : 2006
  • Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research
    Date (from‐to) : 2003 -2004 
    Author : ISHIKAWA Tatsuya, MIURA Seiichi, YOKOHAMA Shoji, SEKINE Etsuo
     
    This study examines the mechanical behavior of granular materials subjected to cyclic moving loads, for example gravel roadbed and railroad ballast, and both a new testing method and new analytical procedures to examine the effects of the rotation of principal stress axes on cyclic plastic deformation of granular materials are proposed. The following conclusions can be obtained ; 1.Cyclic plastic deformation obtained through moving loading tests is much larger than those obtained through fixed-place cyclic loading tests when other experimental conditions are the same. Accordingly, the difference in loading methods has a significant influence on the cyclic plastic deformation of granular materials. 2.Residual strain obtained through cyclic loading triaxial tests with constant amplitude of deviator stress while controlling confining pressure constant is very small compared with the macro residual strain calculated from force-displacement relationships in moving loading tests, while that of cyclic torsional simple shear tests using a newly developed "Multi-ring shear apparatus" is almost equivalent to moving loading tests. Therefore, the multi-ring shear test is appropriate for an element test to simulate the actual stress states inside substructures under traffic loads. Moreover, it was revealed that the rotation of principal stress axes has a significant effect on cyclic deformation characteristics of granular materials. 3.Two analytical procedures for simulating the mechanical behavior of granular materials subjected to cyclic moving loads were proposed. One is linear elastic FE analysis considering the material properties of cumulative strain derived from element test results of granular materials, which can roughly estimate the residual settlement of granular substructures due to cyclic loading. The other is discontinuous analysis which elements imitate the shape of real gram particles well because it was revealed that the element shape is one of the dominant factors to determine the mechanical behavior of granular assemblage in discontinuous analysis.

Educational Activities

Teaching Experience

  • Exercise in Mechanics of Soils
    開講年度 : 2021
    課程区分 : 学士課程
    開講学部 : 工学部
    キーワード : 土の基本的性質、土中水と浸透、地盤内応力と変形、土の圧縮と圧密、応力とテンソルの基礎、破壊基準、排水強度と非排水強度、土圧、斜面の安定、地盤の支持力
  • Civil Engineering Laboratory Ⅱ
    開講年度 : 2021
    課程区分 : 学士課程
    開講学部 : 工学部
    キーワード : 計画・遂行　結果解析　説明能力　土の物理的性質　土の透水性　土の圧縮性　土のせん断強さ　構造　解析　設計　模型作成　荷重試験　
  • Exercise in Applied Mathematics I
    開講年度 : 2021
    課程区分 : 学士課程
    開講学部 : 工学部
    キーワード : 常微分方程式　　ラプラス変換　　フーリエ解析　　偏微分方程式

Copyright © MEDIA FUSION Co.,Ltd. All rights reserved.