2021/04/08 更新

写真a

イチカワ ヤスアキ
市川 康明
ICHIKAWA Yasuaki
所属
中性子医療研究センター 教授(特任)
職名
教授(特任)
外部リンク

学位

  • 科学修士 ( テキサス大学 )

  • 工学博士 ( 名古屋大学 )

研究キーワード

  • 地盤中における汚染物質の吸着・拡散現象の解明

  • Mass transport and sorption of chemical species in geomaterials

  • Numerical simulations of microinhomogeneous materials by molecular simulation and multiscale homogenization analysis

  • 分子シミュレーション法と均質化法によるミクロ非均質材料の数値解析

研究分野

  • 社会基盤(土木・建築・防災) / 地盤工学

  • 社会基盤(土木・建築・防災) / 土木環境システム

  • 情報通信 / 計算科学

所属学協会

▼全件表示

委員歴

  • 日本材料学会   評議員  

    1997年   

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    団体区分:学協会

    日本材料学会

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書籍等出版物

  • "Water flow and diffusion problem in bentonite: Molecular simulation and homogenization analysis", in Coupled Thermo-Hydro-Mechanical-Chemical Processes in Geo-systems

    Elsevier  2005年 

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  • "Water flow and diffusion problem in bentonite: Molecular simulation and homogenization analysis", in Coupled Thermo-Hydro-Mechanical-Chemical Processes in Geo-systems

    Elsevier  2005年 

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  • 粘土の透水性と変形の力学, 「地震発生と水」2.3節

    東京大学出版会  2003年 

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  • 岩盤不連続性の評価と不連続性岩盤の力学, 「ロックメカニックス」第6章

    技報堂出版  2002年 

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  • 地盤力学における有限要素法入門

    日科技連  1990年 

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MISC

  • Coupled diffusion and seepage problem in porous media

    Yasuaki Ichikawa, Jung-Hae Choi, Byung-Cheol Kim

    Zairyo/Journal of the Society of Materials Science, Japan56 ( 9 ) 851 - 857   2007年9月

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    記述言語:日本語  

    Based on mass conservation law a coupled scheme of diffusion and seepage is given for porous media saturated with a multi-component solution. Note that both phenomena have independently treated in the classical theory of porous materials. In the seepage problem we shed light on a physical implication of seepage velocity. In the diffusion problem we show sorption can be introduced on concepts of a source term, a distribution factor or an equation of adsorption isotherm. A practical procedure to evaluate diffusion coefficient is also shown. © 2007 The Society of Materials Science.

    DOI: 10.2472/jsms.56.851

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  • 多孔質体における拡散・浸透問題の関連について

    市川 康明, 崔 定海

    材料56 ( 9 ) 851 - 857   2007年

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  • Observation of microcracks in granite using a confocal laser scanning microscope

    Shixin Liu, A. H. M. Faisal Anwar, Byung Cheol Kim, Yasuaki Ichikawa

    INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES43 ( 8 ) 1293 - 1305   2006年12月

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    記述言語:英語   出版者・発行元:PERGAMON-ELSEVIER SCIENCE LTD  

    DOI: 10.1016/j.ijrmms.2006.04.006

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  • Observation of microcracks in granite using a confocal laser scanning microscope

    Shixin Liu, A. H. M. Faisal Anwar, Byung Cheol Kim, Yasuaki Ichikawa

    INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES43 ( 8 ) 1293 - 1305   2006年12月

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    記述言語:英語   出版者・発行元:PERGAMON-ELSEVIER SCIENCE LTD  

    DOI: 10.1016/j.ijrmms.2006.04.006

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  • Diffusion with micro-sorption in bentonite: evaluation by molecular dynamics and homogenization analysis

    S Prayongphan, Y Ichikawa, K Kawamura, S Suzuki, BG Chae

    COMPUTATIONAL MECHANICS37 ( 4 ) 369 - 380   2006年3月

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    記述言語:英語   出版者・発行元:SPRINGER  

    We here give a numerical analysis method of a diffusion problem including sorption chemistry for bentonite clay. Bentonite predominantly consists of the microscopic smectitic clay minerals (mainly montmorillonite and beidellite). Physico-chemical properties of smectite clays such as diffusivity of chemical species and adsorptivity on surface of clay mineral are characterized by crystalline structure of hydrated smectite minerals. To obtain the microscopic properties of the hydrated smectite, the molecular behavior is analyzed by a molecular dynamic (MD) simulation. We understand at least two types of adsorption are formed on the smectite surface; outer sphere complex and inner sphere complex. The inner sphere complex occurs on the edge sites of clay minerals. The amount of mono-layer of cations on the edge surface is considered as the adsorptivity of smectite in the microscopic level. A multiscale homogenization analysis (HA) is applied to extend the microscopic characteristics of the hydrated smectite to the macroscopic behavior. The diffusion and adsorption of a radioactive specie, cesium (Cs), is introduced by this analysis. The calculated results appear to be acceptable.

    DOI: 10.1007/s00466-005-0676-3

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  • Diffusion with micro-sorption in bentonite: evaluation by molecular dynamics and homogenization analysis

    S Prayongphan, Y Ichikawa, K Kawamura, S Suzuki, BG Chae

    COMPUTATIONAL MECHANICS37 ( 4 ) 369 - 380   2006年3月

     詳細を見る

    記述言語:英語   出版者・発行元:SPRINGER  

    We here give a numerical analysis method of a diffusion problem including sorption chemistry for bentonite clay. Bentonite predominantly consists of the microscopic smectitic clay minerals (mainly montmorillonite and beidellite). Physico-chemical properties of smectite clays such as diffusivity of chemical species and adsorptivity on surface of clay mineral are characterized by crystalline structure of hydrated smectite minerals. To obtain the microscopic properties of the hydrated smectite, the molecular behavior is analyzed by a molecular dynamic (MD) simulation. We understand at least two types of adsorption are formed on the smectite surface; outer sphere complex and inner sphere complex. The inner sphere complex occurs on the edge sites of clay minerals. The amount of mono-layer of cations on the edge surface is considered as the adsorptivity of smectite in the microscopic level. A multiscale homogenization analysis (HA) is applied to extend the microscopic characteristics of the hydrated smectite to the macroscopic behavior. The diffusion and adsorption of a radioactive specie, cesium (Cs), is introduced by this analysis. The calculated results appear to be acceptable.

    DOI: 10.1007/s00466-005-0676-3

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  • Microcrack generation and propagation in granite during stress relaxation under water-saturated tri-axial condition

      62 ( 3 ) 623 - 630   2006年

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  • Microcrack generation and propagation in granite during stress relaxation under water-saturated tri-axial condition

    土木学会論文集C62 ( 3 ) 623 - 630   2006年

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  • 圧縮ベントナイト中の表面拡散現象に関する均質化解析

    応用力学論文集9   2006年

  • Swelling of bentonite in contact with NaCl solutions by using the confocal laser scanning microscope

    Appl. Clay Sci.29   89 - 98   2005年

  • Swelling of bentonite in contact with NaCl solutions by using the confocal laser scanning microscope

    Appl. Clay Sci.29   89 - 98   2005年

  • Long-term behavior consolidation mechanisms based on micro-macro and in situ XRD measurement of basal spacing of clay minerals

    K Nakaoka, S Yamamoto, H Hasegawa, H Kawamura, K Kitayama, N Saito, Y Ichikawa, K Kawamura, M Nakano

    APPLIED CLAY SCIENCE26 ( 1-4 ) 521 - 533   2004年8月

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    記述言語:英語   出版者・発行元:ELSEVIER SCIENCE BV  

    An important issue in the area of geological disposal of high-level radioactive waste (HLW) is to demonstrate the long-term mechanical stability of the buffer. In particular, it has to be clarified whether a waste package would continue to sink in the buffer over a long time period, resulting in a significant decrease in the buffer thickness. The candidate buffer material in Japan is a mixture of silica sand and bentonite. Consolidation tests have revealed that the bentonite shows secondary consolidation phenomena similar to clay in general. Therefore, it is important to investigate the mechanism of secondary consolidation behavior.
    Bentonite is a miroinhomogeneous material consisting of clay minerals, macrograins (mainly quartz) and others. The unique combination of molecular dynamics (MD) and homogenization analysis (HA) procedures, termed the unified MD/HA method, has been proposed for estimating the micro to macro behavior of such an inhomogeneous material (Ichikawa, Y., Kawamura, K., Nakano, M., Kitayama, K., Kawamura, H., 1998. Unified molecular dynamics/homogenization analysis for water flow in bentonite. Proc. 1998 Int. High-Level Radioactive Waste Management Conf., Las Vegas. American Nuclear Society, La Grange Park, IL, pp. 422-428). In this study, the unified MD/HA method is applied to bentonite in order to understand its long-term consolidation mechanism. Thus, it was found that the permeability decreases significantly with a decrease in the void ratio due to the evolution of consolidation. It was therefore assumed that secondary consolidation is governed by drainage from the interlayer pores (micropores) with very low permeability, and that this is the reason why secondary consolidation is very slow.
    This paper also documents the result of an X-ray diffraction (XRD) experiment on bentonite under consolidation (in situ XRD), which was performed in order to validate the assumption mentioned above. It was observed that interlayer space starts to decrease after the latter half of primary consolidation. This finding strongly supports the long-term consolidation mechanism presumed above from a microscopic point of view.
    One-dimensional consolidation analyses of the bentonite, into which the relationship between the void ratio and the permeability determined using the unified MD/HA method was introduced, were performed for comparison with a long-term consolidation test. The good agreement between the analytical result and the test result including secondary consolidation behavior also supports the long-term consolidation mechanism presumed above. (C) 2004 Elsevier B.V. All rights reserved.

    DOI: 10.1016/j.clay.2003.12.022

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  • Microstructure and micro/macro-diffusion behavior of tritium in bentonite

    Y Ichikawa, K Kawamura, N Fujii, K Kitayama

    APPLIED CLAY SCIENCE26 ( 1-4 ) 75 - 90   2004年8月

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    記述言語:英語   出版者・発行元:ELSEVIER SCIENCE BV  

    Diffusion of tritium water, HTO, in bentonite clay is investigated. The method provides a sequential procedure of microscopic characterizations of the clay by a confocal laser scanning microscope (CLSM), the molecular dynamics (MD) simulation and the micro-/macro-analysis by the homogenization analysis (HA) method in which the results of the microscope characterizations and the MD simulations are used. The diffusion properties of HTO calculated by HA agree with the experimental data. Then we simulate the diffusion behavior of HTO in the barrier system of high-level radioactive waste management. (C) 2003 Elsevier B.V. All rights reserved.

    DOI: 10.1016/j.clay.2003.09.013

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  • Microstructure and micro/macro-diffusion behavior of tritium in bentonite

    Y Ichikawa, K Kawamura, N Fujii, K Kitayama

    APPLIED CLAY SCIENCE26 ( 1-4 ) 75 - 90   2004年8月

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    記述言語:英語   出版者・発行元:ELSEVIER SCIENCE BV  

    Diffusion of tritium water, HTO, in bentonite clay is investigated. The method provides a sequential procedure of microscopic characterizations of the clay by a confocal laser scanning microscope (CLSM), the molecular dynamics (MD) simulation and the micro-/macro-analysis by the homogenization analysis (HA) method in which the results of the microscope characterizations and the MD simulations are used. The diffusion properties of HTO calculated by HA agree with the experimental data. Then we simulate the diffusion behavior of HTO in the barrier system of high-level radioactive waste management. (C) 2003 Elsevier B.V. All rights reserved.

    DOI: 10.1016/j.clay.2003.09.013

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  • Long-term behavior consolidation mechanisms based on micro-macro and in situ XRD measurement of basal spacing of clay minerals

    K Nakaoka, S Yamamoto, H Hasegawa, H Kawamura, K Kitayama, N Saito, Y Ichikawa, K Kawamura, M Nakano

    APPLIED CLAY SCIENCE26 ( 1-4 ) 521 - 533   2004年8月

     詳細を見る

    記述言語:英語   出版者・発行元:ELSEVIER SCIENCE BV  

    An important issue in the area of geological disposal of high-level radioactive waste (HLW) is to demonstrate the long-term mechanical stability of the buffer. In particular, it has to be clarified whether a waste package would continue to sink in the buffer over a long time period, resulting in a significant decrease in the buffer thickness. The candidate buffer material in Japan is a mixture of silica sand and bentonite. Consolidation tests have revealed that the bentonite shows secondary consolidation phenomena similar to clay in general. Therefore, it is important to investigate the mechanism of secondary consolidation behavior.
    Bentonite is a miroinhomogeneous material consisting of clay minerals, macrograins (mainly quartz) and others. The unique combination of molecular dynamics (MD) and homogenization analysis (HA) procedures, termed the unified MD/HA method, has been proposed for estimating the micro to macro behavior of such an inhomogeneous material (Ichikawa, Y., Kawamura, K., Nakano, M., Kitayama, K., Kawamura, H., 1998. Unified molecular dynamics/homogenization analysis for water flow in bentonite. Proc. 1998 Int. High-Level Radioactive Waste Management Conf., Las Vegas. American Nuclear Society, La Grange Park, IL, pp. 422-428). In this study, the unified MD/HA method is applied to bentonite in order to understand its long-term consolidation mechanism. Thus, it was found that the permeability decreases significantly with a decrease in the void ratio due to the evolution of consolidation. It was therefore assumed that secondary consolidation is governed by drainage from the interlayer pores (micropores) with very low permeability, and that this is the reason why secondary consolidation is very slow.
    This paper also documents the result of an X-ray diffraction (XRD) experiment on bentonite under consolidation (in situ XRD), which was performed in order to validate the assumption mentioned above. It was observed that interlayer space starts to decrease after the latter half of primary consolidation. This finding strongly supports the long-term consolidation mechanism presumed above from a microscopic point of view.
    One-dimensional consolidation analyses of the bentonite, into which the relationship between the void ratio and the permeability determined using the unified MD/HA method was introduced, were performed for comparison with a long-term consolidation test. The good agreement between the analytical result and the test result including secondary consolidation behavior also supports the long-term consolidation mechanism presumed above. (C) 2004 Elsevier B.V. All rights reserved.

    DOI: 10.1016/j.clay.2003.12.022

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  • Secondary and tertial consolidation of bentonite clay: consolidation test, molecular dynamics simulation and multiscale homogenization analysis

    Y Ichikawa, K Kawamura, N Theramast, K Kitayama

    MECHANICS OF MATERIALS36 ( 5-6 ) 487 - 513   2004年5月

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    記述言語:英語   出版者・発行元:ELSEVIER SCIENCE BV  

    In long-term consolidation process, bentonite shows secondary and tertial stages. Bentonite is a microinhomogeneous material consisting of mainly nanometer scale of smectite clay minerals, micron scale of macro-grains, water, and air. One smectite mineral is a platelet or lamella. Several minerals are piled up and form a stack. In saturated bentonite, water exists both in the interlayer space of stacks and in external pores. The interlayer water is chemically active. Here, we first present experimental results of an in situ X-ray diffraction (XRD) analysis during consolidation process. The data suggest that at the first stage of consolidation, water is drained from external pores, and at the secondary stage, the interlayer water is drained. Second, molecular dynamics (MD) analyses are applied to specify local properties of hydrated smectite. We also show that by MD the secondary consolidation is not caused by visco-elastic characteristics of clay skeleton. Third, we present a multiscale homogenization analysis (HA) method applied to the seepage behavior of bentonite. Here, the local property of water viscosity calculated by MD is used. Fourth, the results of permeability change are introduced in a 1-D finite strain consolidation analysis, which can represent the secondary consolidation behavior. And if multicharged anions are infiltrated, the chemical properties of bentonite are drastically changed. This causes a change of permeability. This is a major factor of the tertial consolidation. We discuss an analysis method of tertial consolidation because of this permeability change. (C) 2003 Elsevier Ltd. All rights reserved.

    DOI: 10.1016/S0167-6636(03)00073-5

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  • Secondary and tertial consolidation of bentonite clay: consolidation test, molecular dynamics simulation and multiscale homogenization analysis

    Y Ichikawa, K Kawamura, N Theramast, K Kitayama

    MECHANICS OF MATERIALS36 ( 5-6 ) 487 - 513   2004年5月

     詳細を見る

    記述言語:英語   出版者・発行元:ELSEVIER SCIENCE BV  

    In long-term consolidation process, bentonite shows secondary and tertial stages. Bentonite is a microinhomogeneous material consisting of mainly nanometer scale of smectite clay minerals, micron scale of macro-grains, water, and air. One smectite mineral is a platelet or lamella. Several minerals are piled up and form a stack. In saturated bentonite, water exists both in the interlayer space of stacks and in external pores. The interlayer water is chemically active. Here, we first present experimental results of an in situ X-ray diffraction (XRD) analysis during consolidation process. The data suggest that at the first stage of consolidation, water is drained from external pores, and at the secondary stage, the interlayer water is drained. Second, molecular dynamics (MD) analyses are applied to specify local properties of hydrated smectite. We also show that by MD the secondary consolidation is not caused by visco-elastic characteristics of clay skeleton. Third, we present a multiscale homogenization analysis (HA) method applied to the seepage behavior of bentonite. Here, the local property of water viscosity calculated by MD is used. Fourth, the results of permeability change are introduced in a 1-D finite strain consolidation analysis, which can represent the secondary consolidation behavior. And if multicharged anions are infiltrated, the chemical properties of bentonite are drastically changed. This causes a change of permeability. This is a major factor of the tertial consolidation. We discuss an analysis method of tertial consolidation because of this permeability change. (C) 2003 Elsevier Ltd. All rights reserved.

    DOI: 10.1016/S0167-6636(03)00073-5

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  • Roughness measurement of rock discontinuities using a confocal laser scanning microscope and the Fourier spectral analysis

    BG Chae, Y Ichikawa, GC Jeong, YS Seo, BC Kim

    ENGINEERING GEOLOGY72 ( 3-4 ) 181 - 199   2004年4月

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    記述言語:英語   出版者・発行元:ELSEVIER SCIENCE BV  

    The fracture roughness of rock specimens is observed by a new confocal laser scanning microscope (CLSM; Olympus OLS1100). The wavelength of the laser is 488 nm, and laser scanning is managed by a light polarization method using two galvano-meter scanner mirrors. The function of laser reflection auto-focusing enables line data to be measured rapidly and precisely. The system improves the resolution in the light axis (namely z) direction because of the confocal optics. It is possible to measure a specimen of up to 10 x 10 cm in size when fixed on a specially designed stage. Sampling is managed with a 2.5-mum spacing along the x and y directions. The highest measurement resolution in the z direction is 0.05 mum, which is more accurate than other methods.
    Core specimens of coarse and fine grained granites were provided and fractures were artificially induced by a Brazilian test method. Measurements were performed along three scan lines on each fracture surface. The measured data were represented as 2-D and 3-D digital images showing detailed features of roughness. Line profiles of the coarse granites showed more changes of undulation than those of the fine granite. Spectral analyses by the fast Fourier transform (FFT) were performed to characterize the roughness data quantitatively and to identify influential frequency of roughness. The FFT results show that components of low frequencies are dominant in the fracture roughness. This study also verifies that spectral analysis is a good approach to understand complicated characteristics of fracture roughness. One of the ultimate objectives of the study was to suggest a methodology to select effective frequencies among the constituent frequencies of roughness as measured with very accurate measurement equipment. The other objective was to perform reconstruction of roughness with noise filtering which will be applied as input data to a fracture model for a numerical analysis. (C) 2003 Elsevier B.V. All rights reserved.

    DOI: 10.1016/j.enggeo.2003.08.002

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  • Roughness measurement of rock discontinuities using a confocal laser scanning microscope and the Fourier spectral analysis

    BG Chae, Y Ichikawa, GC Jeong, YS Seo, BC Kim

    ENGINEERING GEOLOGY72 ( 3-4 ) 181 - 199   2004年4月

     詳細を見る

    記述言語:英語   出版者・発行元:ELSEVIER SCIENCE BV  

    The fracture roughness of rock specimens is observed by a new confocal laser scanning microscope (CLSM; Olympus OLS1100). The wavelength of the laser is 488 nm, and laser scanning is managed by a light polarization method using two galvano-meter scanner mirrors. The function of laser reflection auto-focusing enables line data to be measured rapidly and precisely. The system improves the resolution in the light axis (namely z) direction because of the confocal optics. It is possible to measure a specimen of up to 10 x 10 cm in size when fixed on a specially designed stage. Sampling is managed with a 2.5-mum spacing along the x and y directions. The highest measurement resolution in the z direction is 0.05 mum, which is more accurate than other methods.
    Core specimens of coarse and fine grained granites were provided and fractures were artificially induced by a Brazilian test method. Measurements were performed along three scan lines on each fracture surface. The measured data were represented as 2-D and 3-D digital images showing detailed features of roughness. Line profiles of the coarse granites showed more changes of undulation than those of the fine granite. Spectral analyses by the fast Fourier transform (FFT) were performed to characterize the roughness data quantitatively and to identify influential frequency of roughness. The FFT results show that components of low frequencies are dominant in the fracture roughness. This study also verifies that spectral analysis is a good approach to understand complicated characteristics of fracture roughness. One of the ultimate objectives of the study was to suggest a methodology to select effective frequencies among the constituent frequencies of roughness as measured with very accurate measurement equipment. The other objective was to perform reconstruction of roughness with noise filtering which will be applied as input data to a fracture model for a numerical analysis. (C) 2003 Elsevier B.V. All rights reserved.

    DOI: 10.1016/j.enggeo.2003.08.002

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  • Aperture of granite fracture and effects for fluid flow

    BG Chae, Y Ichikawa, GC Jeong, YS Seo

    MATERIALS SCIENCE RESEARCH INTERNATIONAL9 ( 4 ) 270 - 277   2003年12月

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    記述言語:英語   出版者・発行元:SOC MATERIALS SCIENCE, JAPAN  

    Fluid flow in rock mass is controlled by geometry of fractures which is mainly characterized by roughness, aperture and orientation. In this study we measure the aperture of rock fractures using a high resolution confocal laser scanning microscope (CLSM). Digital images of the aperture are acquired under applying five stages of uniaxial normal stresses. The error range is less than 0.125mum. It has been difficult to check the aperture change under stress application for the same specimen continuously. Our method can characterize the response of aperture. Results of measurements show that roughness geometry of fracture bears no uniform aperture. That is, it is changed in nonuniform manner under the different stress levels: Some parts bear a smaller aperture because of the applied stress, while some parts with very narrow aperture develop new cracks or shear displacement because of no space of aperture reduction. Laboratory permeability tests are also conducted to evaluate changes of permeability related to aperture variation due to different stress levels. The results do not imply a simple reduction of hydraulic conductivity under increase of the normal stress. This suggests that the mechanical aperture is different from the hydraulic aperture which is an effective conduit of fluid flow along a fracture. It is shown that the hydraulic aperture is slightly smaller than the mechanical aperture. Clearly the flow channels are changed due to the local change of geometry under the applied stress. The hydraulic conductivity does not follow the cubic law. This means that a parallel plate model is not suitable to express the hydraulic conductivity including local fracture geometry.

    DOI: 10.2472/jsms.52.12Appendix_270

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  • Aperture of granite fracture and effects for fluid flow

    BG Chae, Y Ichikawa, GC Jeong, YS Seo

    MATERIALS SCIENCE RESEARCH INTERNATIONAL9 ( 4 ) 270 - 277   2003年12月

     詳細を見る

    記述言語:英語   出版者・発行元:SOC MATERIALS SCIENCE, JAPAN  

    Fluid flow in rock mass is controlled by geometry of fractures which is mainly characterized by roughness, aperture and orientation. In this study we measure the aperture of rock fractures using a high resolution confocal laser scanning microscope (CLSM). Digital images of the aperture are acquired under applying five stages of uniaxial normal stresses. The error range is less than 0.125mum. It has been difficult to check the aperture change under stress application for the same specimen continuously. Our method can characterize the response of aperture. Results of measurements show that roughness geometry of fracture bears no uniform aperture. That is, it is changed in nonuniform manner under the different stress levels: Some parts bear a smaller aperture because of the applied stress, while some parts with very narrow aperture develop new cracks or shear displacement because of no space of aperture reduction. Laboratory permeability tests are also conducted to evaluate changes of permeability related to aperture variation due to different stress levels. The results do not imply a simple reduction of hydraulic conductivity under increase of the normal stress. This suggests that the mechanical aperture is different from the hydraulic aperture which is an effective conduit of fluid flow along a fracture. It is shown that the hydraulic aperture is slightly smaller than the mechanical aperture. Clearly the flow channels are changed due to the local change of geometry under the applied stress. The hydraulic conductivity does not follow the cubic law. This means that a parallel plate model is not suitable to express the hydraulic conductivity including local fracture geometry.

    DOI: 10.2472/jsms.52.12Appendix_270

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  • Local structural information of Cs in smectite hydrates by means of an EXAFS study and molecular dynamics simulations

    M Nakano, K Kawamura, Y Ichikawa

    APPLIED CLAY SCIENCE23 ( 1-4 ) 15 - 23   2003年8月

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    記述言語:英語   出版者・発行元:ELSEVIER SCIENCE BV  

    To elucidate the behavior of Cs atoms and the adsorption sites for Cs atoms in clays, molecular structural information around Cs atoms adsorbed in bentonite (montmorillonite-beidellite) at pH 3.9, 7.1, and 9.8 has been investigated in extended X-ray absorption fine structure (EXAFS) spectroscopy using a crystalline Cs2SO4 as a model compound. Molecular dynamics (MD) simulations were also performed on beidellite. The basic cube cell used for MD simulations contained 3972 atoms, including two Cl atoms in the interlayer water. In EXAFS analyses, the first coordination shell formed by oxygen of water molecules was observed at a distance of 3.15-3.16 Angstrom, with the coordination number of 7.0-7.4. The second coordination shell consisted of 60 atoms forming clay minerals at a distance of 3.59-3.62 Angstrom. In MD simulations, many Cs atoms were found to roam much more freely over the mineral surface, and even in the interlayer water. The results suggested that the inner-sphere surface complexes coexisted with the outer-sphere surface complexes, and that the adsorbed sites were positioned nearby the edge of the basal oxygen hexagonal cavity on tetrahedral sheets in Kunipia F bentonite. (C) 2003 Elsevier Science B.V. All rights reserved.

    DOI: 10.1016/S0169-1317(03)00082-6

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  • Local structural information of Cs in smectite hydrates by means of an EXAFS study and molecular dynamics simulations

    M Nakano, K Kawamura, Y Ichikawa

    APPLIED CLAY SCIENCE23 ( 1-4 ) 15 - 23   2003年8月

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    記述言語:英語   出版者・発行元:ELSEVIER SCIENCE BV  

    To elucidate the behavior of Cs atoms and the adsorption sites for Cs atoms in clays, molecular structural information around Cs atoms adsorbed in bentonite (montmorillonite-beidellite) at pH 3.9, 7.1, and 9.8 has been investigated in extended X-ray absorption fine structure (EXAFS) spectroscopy using a crystalline Cs2SO4 as a model compound. Molecular dynamics (MD) simulations were also performed on beidellite. The basic cube cell used for MD simulations contained 3972 atoms, including two Cl atoms in the interlayer water. In EXAFS analyses, the first coordination shell formed by oxygen of water molecules was observed at a distance of 3.15-3.16 Angstrom, with the coordination number of 7.0-7.4. The second coordination shell consisted of 60 atoms forming clay minerals at a distance of 3.59-3.62 Angstrom. In MD simulations, many Cs atoms were found to roam much more freely over the mineral surface, and even in the interlayer water. The results suggested that the inner-sphere surface complexes coexisted with the outer-sphere surface complexes, and that the adsorbed sites were positioned nearby the edge of the basal oxygen hexagonal cavity on tetrahedral sheets in Kunipia F bentonite. (C) 2003 Elsevier Science B.V. All rights reserved.

    DOI: 10.1016/S0169-1317(03)00082-6

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  • A constitutive model for rock interfaces and joint

    Int. J. Rock Mech. & Min. Sci40 ( 1 ) 41 - 53   2003年

  • A constitutive model for rock interfaces and joint

    WANG J G, ICHIKAWA Y, LEUNG C F

    Int. J. Rock Mech. & Min. Sci40 ( 1 ) 41 - 53   2003年

  • 粘土鉱物-水界面における水の分光学的性質と動的性質の関係

    鈴木覚, 河村雄行, 中島善人, 市川康明

    資源と素材119 ( 9 ) 581 - 586   2003年

  • Molecular dynamics and multiscale homogenization analysis of seepage/diffusion problem in bentonite clay

    Int. J. Numer. Meth. Engng55   1 - 40   2002年

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  • 地盤力学における二重空隙理論と多段階均質化法

    材料51 ( 2 ) 2002   2002年

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  • Micro/macro-behavior of water flow and diffusion in clay: Multiscale homogenization analysis

    Bull. Earthquake Research Institute, Univ. Tokyo76   425 - 441   2002年

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  • Molecular dynamics and multiscale homogenization analysis of seepage/diffusion problem in bentonite clay

    Int. J. Numer. Meth. Engng55   1 - 40   2002年

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  • 高レベル放射性廃棄物の地層処分と分子動力学法による物質移行シミュレーション

    日本シミュレーション学会誌21 ( 1 ) 9 - 14   2002年

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  • Micro/macro-behavior of water flow and diffusion in clay: Multiscale homogenization analysis

    Bull. Earthquake Research Institute, Univ. Tokyo76   425 - 441   2002年

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  • Seepage and consolidation of bentonite saturated with pure- or salt-water by the method of unified molecular dynamics and homogenization analysis

    Y Ichikawa, K Kawamura, M Nakano, K Kitayama, T Seiki, N Theramast

    ENGINEERING GEOLOGY60 ( 1-4 ) 127 - 138   2001年6月

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    記述言語:英語   出版者・発行元:ELSEVIER SCIENCE BV  

    Bentonite clay is a micro-inhomogeneous material, which consists of clay minerals (mainly montmorillonite), macro-grains (mainly quartz), water, air and others, Properties of the saturated bentonite clay are essentially characterized by the montmorillonite and water (i.e. montmorillonite hydrate), We analyze the molecular behavior of sodium montmorillonite hydrate Na-1/3, Al-2[Si11/3Al1/3]O-10(OH)(2). nH(2)O by applying a molecular dynamics (MD) simulation method. And by using the MD results we calculate the swelling property of the montmorillonite hydrate, and compare with an experimental result. Next, by using the same MD procedure we treat a montmorillonite mineral with a large number of external water molecules to check the properties of the water, Here we treat pure- and salt-water. Then we calculate the diffusivity and viscosity of water molecules and Na+ and Cl- ions.
    For extending the microscopic characteristics of constituent materials to a macroscopic seepage behavior of the micro-inhomogeneous material we apply a homogenization analysis (HA), That is, starting with the Navier-Stokes equation with distributed viscosity that is calculated by the former MD procedure we determine macroscopic permeability characteristics of bentonite for both cases of pure- and salt-water. Then, by using the permeability property we calculate long-term consolidation behavior of buffering clay, which is planed to be used for high-level radioactive waste (HLRW) management. Here the deformation is treated under the well-defined Cam clay model. (C) 2001 Elsevier Science B.V. All rights reserved.

    DOI: 10.1016/S0013-7952(00)00095-8

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  • Seepage and consolidation of bentonite saturated with pure- or salt-water by the method of unified molecular dynamics and homogenization analysis

    Y Ichikawa, K Kawamura, M Nakano, K Kitayama, T Seiki, N Theramast

    ENGINEERING GEOLOGY60 ( 1-4 ) 127 - 138   2001年6月

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    記述言語:英語   出版者・発行元:ELSEVIER SCIENCE BV  

    Bentonite clay is a micro-inhomogeneous material, which consists of clay minerals (mainly montmorillonite), macro-grains (mainly quartz), water, air and others, Properties of the saturated bentonite clay are essentially characterized by the montmorillonite and water (i.e. montmorillonite hydrate), We analyze the molecular behavior of sodium montmorillonite hydrate Na-1/3, Al-2[Si11/3Al1/3]O-10(OH)(2). nH(2)O by applying a molecular dynamics (MD) simulation method. And by using the MD results we calculate the swelling property of the montmorillonite hydrate, and compare with an experimental result. Next, by using the same MD procedure we treat a montmorillonite mineral with a large number of external water molecules to check the properties of the water, Here we treat pure- and salt-water. Then we calculate the diffusivity and viscosity of water molecules and Na+ and Cl- ions.
    For extending the microscopic characteristics of constituent materials to a macroscopic seepage behavior of the micro-inhomogeneous material we apply a homogenization analysis (HA), That is, starting with the Navier-Stokes equation with distributed viscosity that is calculated by the former MD procedure we determine macroscopic permeability characteristics of bentonite for both cases of pure- and salt-water. Then, by using the permeability property we calculate long-term consolidation behavior of buffering clay, which is planed to be used for high-level radioactive waste (HLRW) management. Here the deformation is treated under the well-defined Cam clay model. (C) 2001 Elsevier Science B.V. All rights reserved.

    DOI: 10.1016/S0013-7952(00)00095-8

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  • Micro- and macrobehavior of granitic rock: observations and viscoelastic homogenization analysis

    Y Ichikawa, K Kawamura, K Uesugi, YS Seo, N Fujii

    COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING191 ( 1-2 ) 47 - 72   2001年

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    記述言語:英語   出版者・発行元:ELSEVIER SCIENCE SA  

    Microscopic structures must be determined for analyzing the behavior of microinhomogeneous materials such as crystalline rocks. We observe a three-dimensional texture of granitic rock by X-ray tomographic microscopy (XTM) images using an ultra-bright synchrotron radiation (SR)-CT system. The time-dependent fracturing behavior of granite for relaxation tests is, then, observed by microscope under water-saturated triaxial stress conditions. Next, in order to know properties of each constituent mineral and their interfaces, we introduce the Molecular Dynamics (MD) computer simulation method. Based on these facts we establish a micro/macromodel of granite by a homogenization analysis method to simulate the viscoclastic behavior. (C) 2001 Elsevier Science B.V. All rights reserved.

    DOI: 10.1016/S0045-7825(01)00244-4

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  • Physical properties of clay minerals and water: -by means of molecular dynamics simulations-

    Bull. Earthquake Research Institute, Univ. Tokyo76   311 - 321   2001年

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  • Physical properties of clay minerals and water: -by means of molecular dynamics simulations-

    Bull. Earthquake Research Institute, Univ. Tokyo76   311 - 321   2001年

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  • Micro- and macrobehavior of granitic rock: observations and viscoelastic homogenization analysis

    Y Ichikawa, K Kawamura, K Uesugi, YS Seo, N Fujii

    COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING191 ( 1-2 ) 47 - 72   2001年

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    記述言語:英語   出版者・発行元:ELSEVIER SCIENCE SA  

    Microscopic structures must be determined for analyzing the behavior of microinhomogeneous materials such as crystalline rocks. We observe a three-dimensional texture of granitic rock by X-ray tomographic microscopy (XTM) images using an ultra-bright synchrotron radiation (SR)-CT system. The time-dependent fracturing behavior of granite for relaxation tests is, then, observed by microscope under water-saturated triaxial stress conditions. Next, in order to know properties of each constituent mineral and their interfaces, we introduce the Molecular Dynamics (MD) computer simulation method. Based on these facts we establish a micro/macromodel of granite by a homogenization analysis method to simulate the viscoclastic behavior. (C) 2001 Elsevier Science B.V. All rights reserved.

    DOI: 10.1016/S0045-7825(01)00244-4

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  • 圧縮ベントナイトの微細構造のモデル化とMD-HA結合解析法の拡散問題への適用

    鈴木 覚, 藤島 敦, 上野 健一, 市川 康明, 河村 雄行, 藤井 直樹, 柴田 雅博, 佐藤 治夫, 北山 一美

    粘土科学41 ( 2 ) 43 - 57   2001年

  • Inverse analysis procedure for identifying material parameters of hypoplastic constitutive model for soils

    P Dziadziuszko, Y Ichikawa, Z Sikora

    MATERIALS SCIENCE RESEARCH INTERNATIONAL6 ( 3 ) 212 - 220   2000年9月

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    記述言語:英語   出版者・発行元:SOC MATERIALS SCIENCE, JAPAN  

    In this paper we present an inverse analysis method for material parameter identification applied to the hypoplastic constitutive model for soils. The proposed method is classified as a direct-approach one, since the discrepancy between the material responses, measured and calculated by means of the finite element method is directly minimized. In the presented work this minimization is made up of the modified Levenberg-Marquardt optimization method based on the so-called trust region approach. We provide a numerical example of parameter identification for a triaxial test performed on a sand material, supplemented by the analysis of the influence of the initial guesses of the parameters to be identified, as well as the errors in the measured control data on the identification process.

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  • Viscoelastic behavior of granite and the homogenization analysis

    YS Seo, N Fujii, T Seiki, Y Ichikawa

    MATERIALS SCIENCE RESEARCH INTERNATIONAL6 ( 3 ) 203 - 211   2000年9月

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    記述言語:英語   出版者・発行元:SOC MATERIALS SCIENCE, JAPAN  

    Granite is a composite material of rock-forming minerals with discontinuous joints such as grain boundaries and microcracks. Studies of these microstructures are of increasing interest in geophysics and geotechnical engineering relating to underground space development. We first performed uniaxial compressive and relaxation tests for estimating physical properties of discontinuous joints by using three kinds of rocks that consist of quartz, quartz/feldspar and feldspar, respectively. Next a homogenization method is applied to analyze a viscoelastic behavior of granite including these joints.

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  • Viscoelastic behavior of granite and the homogenization analysis

    YS Seo, N Fujii, T Seiki, Y Ichikawa

    MATERIALS SCIENCE RESEARCH INTERNATIONAL6 ( 3 ) 203 - 211   2000年9月

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    記述言語:英語   出版者・発行元:SOC MATERIALS SCIENCE, JAPAN  

    Granite is a composite material of rock-forming minerals with discontinuous joints such as grain boundaries and microcracks. Studies of these microstructures are of increasing interest in geophysics and geotechnical engineering relating to underground space development. We first performed uniaxial compressive and relaxation tests for estimating physical properties of discontinuous joints by using three kinds of rocks that consist of quartz, quartz/feldspar and feldspar, respectively. Next a homogenization method is applied to analyze a viscoelastic behavior of granite including these joints.

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  • Inverse analysis procedure for identifying material parameters of hypoplastic constitutive model for soils

    P Dziadziuszko, Y Ichikawa, Z Sikora

    MATERIALS SCIENCE RESEARCH INTERNATIONAL6 ( 3 ) 212 - 220   2000年9月

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    記述言語:英語   出版者・発行元:SOC MATERIALS SCIENCE, JAPAN  

    In this paper we present an inverse analysis method for material parameter identification applied to the hypoplastic constitutive model for soils. The proposed method is classified as a direct-approach one, since the discrepancy between the material responses, measured and calculated by means of the finite element method is directly minimized. In the presented work this minimization is made up of the modified Levenberg-Marquardt optimization method based on the so-called trust region approach. We provide a numerical example of parameter identification for a triaxial test performed on a sand material, supplemented by the analysis of the influence of the initial guesses of the parameters to be identified, as well as the errors in the measured control data on the identification process.

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  • Unified molecular dynamics and homogenization analysis for bentonite behavior: current results and future possibilities

    Y Ichikawa, K Kawamura, M Nakano, K Kitayama, H Kawamura

    ENGINEERING GEOLOGY54 ( 1-2 ) 21 - 31   1999年9月

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    記述言語:英語   出版者・発行元:ELSEVIER SCIENCE BV  

    In high-level radioactive waste disposal, one of the key issues is predicting the behavior of bentonite, which is an important component of the engineering barrier system (EBS). However any existing macro-phenomenological models are basically insufficient for assessing the true behavior of bentonite clay.
    Clay is a typical micro-inhomogeneous material. It consists of clay minerals, macro-grains (quartz etc.), water, air etc. as its microscopic level components. There are two essential issues to be considered in analyzing the behavior of such micro-inhomogeneous materials: one is how to determine the characteristics of constituent components, which are directly affected by molecular movement; and the other is how to relate the microscopic characteristics to the macroscopic behavior. For solving the first problem, we apply the molecular dynamics method (MD) to determine the material properties of each constituent component, then homogenization analysis (HA) (Sanchez-Palencia, 1980, Non-homogeneous Media and Vibration Theory. Springer-Verlag, Berlin; Bakhvalov and Panasenko, 1984, Homogenization: Averaging Processes in Periodic Media, Nauka, Moscow) is used for estimating the micro to macro behaviors, This unique combination procedure of the MD and the HA is called the unified MD/HA method, and we applied this method to the time-dependent visco-elastic problem (Kawamura et al., 1997, A new approach for predicting the long term behavior of bentonite: the unified method of molecular dynamics and homogenization analysis. Proc. Scientific Basis for Nuclear Waste Management XXI, Davos. Switzerland, Material Research Society, pp. 359-366) and the seepage problem (Ichikawa et al., 1998, Unified molecular dynamics/homogenization analysis for water flow in bentonite, Proc. 1998 Int. High-Level Radioactive Waste Management Conf., Las Vegas, American Nuclear Society, pp. 422-428).
    We present here a summary of the previous works, and discuss the further possibilities of the unified MD/HA procedure. (C) 1999 Elsevier Science B.V. All rights reserved.

    DOI: 10.1016/S0013-7952(99)00058-7

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  • Unified molecular dynamics and homogenization analysis for bentonite behavior: current results and future possibilities

    Y Ichikawa, K Kawamura, M Nakano, K Kitayama, H Kawamura

    ENGINEERING GEOLOGY54 ( 1-2 ) 21 - 31   1999年9月

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    記述言語:英語   出版者・発行元:ELSEVIER SCIENCE BV  

    In high-level radioactive waste disposal, one of the key issues is predicting the behavior of bentonite, which is an important component of the engineering barrier system (EBS). However any existing macro-phenomenological models are basically insufficient for assessing the true behavior of bentonite clay.
    Clay is a typical micro-inhomogeneous material. It consists of clay minerals, macro-grains (quartz etc.), water, air etc. as its microscopic level components. There are two essential issues to be considered in analyzing the behavior of such micro-inhomogeneous materials: one is how to determine the characteristics of constituent components, which are directly affected by molecular movement; and the other is how to relate the microscopic characteristics to the macroscopic behavior. For solving the first problem, we apply the molecular dynamics method (MD) to determine the material properties of each constituent component, then homogenization analysis (HA) (Sanchez-Palencia, 1980, Non-homogeneous Media and Vibration Theory. Springer-Verlag, Berlin; Bakhvalov and Panasenko, 1984, Homogenization: Averaging Processes in Periodic Media, Nauka, Moscow) is used for estimating the micro to macro behaviors, This unique combination procedure of the MD and the HA is called the unified MD/HA method, and we applied this method to the time-dependent visco-elastic problem (Kawamura et al., 1997, A new approach for predicting the long term behavior of bentonite: the unified method of molecular dynamics and homogenization analysis. Proc. Scientific Basis for Nuclear Waste Management XXI, Davos. Switzerland, Material Research Society, pp. 359-366) and the seepage problem (Ichikawa et al., 1998, Unified molecular dynamics/homogenization analysis for water flow in bentonite, Proc. 1998 Int. High-Level Radioactive Waste Management Conf., Las Vegas, American Nuclear Society, pp. 422-428).
    We present here a summary of the previous works, and discuss the further possibilities of the unified MD/HA procedure. (C) 1999 Elsevier Science B.V. All rights reserved.

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  • Stress-strain response of rock-forming minerals by molecular dynamics simulation

    Material Science Research International5 ( 1 ) 13   1999年

  • マイクロクラックの発生・進展に起因した結晶質岩の応力緩和現象に関する水浸一軸試験

    徐 庸碩, 清木 隆文, 市川 康明

    材料48 ( 11 ) 1255 - 1262   1999年

  • Back analysis of large geotechnical model

    Int. J. Numer. Anal. Meth. Geomech.23 ( 13 ) 1455 - 1472   1999年

  • Crack generation and propagation during stress relaxation of crystalline rock under water-saturated uniaxial condition

    Yong-Seok Seo, Takafumi Seiki, Yasuaki Ichikawa

    Zairyo/Journal of the Society of Materials Science, Japan48 ( 11 ) 1255 - 1262   1999年

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    記述言語:日本語   出版者・発行元:Soc Mater Sci, Japan  

    Microcrack generation and propagation play an essential role to predict the long-term behavior of crystalline rock. We developed a new relaxation testing equipment that enables us to observe a granite specimen under the state of relaxation. Series of relaxation tests have been performed under constant temperature. In this paper, we show a few patterns of microcrack propagation and the relationship between pre-existed crack and crack development under the state of relaxation.

    DOI: 10.2472/jsms.48.1255

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  • Unified molecular simulation/homogenization method - An analysis of bentonite clay in high-level radioactive waste management

    J. Atomic Energy Soc. Japan41 ( 2 ) 88 - 97   1999年

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  • 分子シミュレーション法と均質化法の結合解析:高レベル放射性廃棄物の地層処分における緩衝材挙動への適用

    市川康明, 河村雄行, 中野政詩, 北山一美

    日本原子力学会誌41 ( 2 ) 88 - 97   1999年

  • Back analysis of large geotechnical model

    SWOBODA G, ICHIKAWA Y, DONG Q, ZAKI M

    Int. J. Numer. Anal. Meth. Geomech.23 ( 13 ) 1455 - 1472   1999年

  • 粘土鉱物―水系の分子動力学シミュレーション―廃棄物地層処分の人工バリアの性能評価に向けて―

    月刊地球21 ( 2 ) 97 - 101   1999年

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  • Stress-strain response of rock-forming minerals by molecular dynamics simulation

    Material Science Research International5 ( 1 ) 13   1999年

  • Unified molecular dynamics/homogenization analysis for water flow in bentonite

    Proc. 1998 Int. High-Level Radioactive Waste Management Conf.   422 - 428   1998年

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  • Unified molecular dynamics/homogenization analysis for water flow in bentonite

    Proc. 1998 Int. High-Level Radioactive Waste Management Conf.   422 - 428   1998年

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  • Impact of fast parameter identification to tunnel analysis

    Proc. World Tunnel Congress '97   115 - 120   1997年

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  • A parameter identification procedure for viscoelastic materials

    Comp. Geomech.21 ( 4 ) 255 - 275   1997年

  • A parameter identification procedure for viscoelastic materials

    OHKAMI T, ICHIKAWA Y

    Comp. Geomech.21 ( 4 ) 255 - 275   1997年

  • Impact of fast parameter identification to tunnel analysis

    Proc. World Tunnel Congress '97   115 - 120   1997年

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  • Nonlinear soil parameter identification and an expert system

    Proc. Int. Conf. Advanced Tech. in Experimental Mech.   71 - 76   1997年

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  • A new approach for predicting the long term behavior of bentonite: The unified method of molecular dynamics and homogenization analysis

    Scientific Basis for Nuclear Waste Management XXI   359 - 366   1997年

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  • Nonlinear soil parameter identification and an expert system

    Proc. Int. Conf. Advanced Tech. in Experimental Mech.   71 - 76   1997年

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  • A new approach for predicting the long term behavior of bentonite: The unified method of molecular dynamics and homogenization analysis

    Scientific Basis for Nuclear Waste Management XXI   359 - 366   1997年

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  • Micro/macro properties of geomaterials: A homogenization method for viscoelastic problem

    Int. J. Structural Eng. Mech.4 ( 6 ) 631   1996年

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  • A homogenization theory for elasto-visco-plastic materials and its application for rock and soil

    Proc. Asia-Pacific Symp. Advances in Eng. Plasticity and Its Applications   427 - 432   1996年

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  • Micro/macro properties of geomaterials: A homogenization method for viscoelastic problem

    Int. J. Structural Eng. Mech.4 ( 6 ) 631   1996年

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  • Deformation and failure of crystalline rock and an elastoplastic homogenization theory

    Y Ichikawa, J Wang

    EUROCK '96/TORINO/ITALY - PREDICTION AND PERFORMANCE IN ROCK MECHANICS AND ROCK ENGINEERING, PROCEEDINGS, VOLS 1 AND 2   367 - 375   1996年

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    記述言語:英語   出版者・発行元:A A BALKEMA  

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  • An elastoplastic homogenization theory for geomaterials

    Proc. 3rd Asian-Pacific Conf. Compatational Mech.   2205 - 2212   1996年

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  • Deformation and failure of crystalline rock and an elastoplastic homogenization theory

    Y Ichikawa, J Wang

    EUROCK '96/TORINO/ITALY - PREDICTION AND PERFORMANCE IN ROCK MECHANICS AND ROCK ENGINEERING, PROCEEDINGS, VOLS 1 AND 2   367 - 375   1996年

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    記述言語:英語   出版者・発行元:A A BALKEMA  

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  • ミクロとマクロを結ぶ力学 II.粘弾性体の均質化理論

    京都大学水曜会誌22 ( 6 ) 344 - 353   1996年

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  • A homogenization theory for elasto-visco-plastic materials and its application for rock and soil

    Proc. Asia-Pacific Symp. Advances in Eng. Plasticity and Its Applications   427 - 432   1996年

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  • An elastoplastic homogenization theory for geomaterials

    Proc. 3rd Asian-Pacific Conf. Compatational Mech.   2205 - 2212   1996年

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  • 対流を考慮した熱・応力・浸透連成挙動の混合体理論とその多孔質地盤への適用

    清木 隆文, 市川 康明

    土木学会論文集 ( 517 ) 1 - 11   1995年

  • ミクロとマクロを結ぶ力学 Ⅰ.岩石の微視的変形・破壊挙動の観察

    水曜会誌22 ( 4 ) 193 - 201   1995年

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  • An Experimental Study on Damage Propagation of Intact Granite

    Gyo-cheol Jeong, Yasuaki Ichikawa

    Journal of the Society of Materials Science, Japan43 ( 486 ) 317 - 323   1994年

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    記述言語:英語  

    Microcracks during complex loading could result from the tensile stress concentration around such flaws as grain boundary microcracks, intracrystalline microcracks and microcavities. Therefore, detailed knowledge about microcracks substantially contributes to the interpretation of damaging process, microcrack-induced dilatancy and failure in intact rock. In the present study, a direct observation of actual damage propagation in intact granite specimens which are cut from a block of coarse grained granite was carried out by a newly developed experimental system. Microscopic observation shows that an incipient micro-damage is generated at two grain contact portion due to elastic mismatch of the two grains, and their morphologies are parallel or subparallel to the axial stress direction. The detailed observation of an incipient shear fracture in a granite specimen suggests that the fracture is formed by the coalescence through the inclined grain boundaries of links between echelon intracrystalline microcracks. © 1994, The Society of Materials Science, Japan. All rights reserved.

    DOI: 10.2472/jsms.43.317

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  • コンプリメンタリエネルギー等価仮説による岩盤の損傷学モデルとその地下空洞掘削問題への適用

    呉 旭, 市川 康明, 京谷 孝史, 川本 〓万

    土木学会論文集 ( 505 ) 115 - 122   1994年

  • Micro-damage propagation in marble under triaxial state of stress

    Gyo-Cheol JEONG, Yasuaki ICHIKAWA

    J. Mining and Material Processing Inst. Japan110 ( 4 ) 283 - 288   1994年

  • 花崗岩におけるマイクロクラックの進展に関する実験的研究

    材料43 ( 486 ) 317 - 323   1994年

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  • Micro-damage propagation in marble under triaxial state of stress

    鄭 教撤, 市川 康明

    資源と素材110 ( 4 ) 283 - 288   1994年

  • Biomechanical study on mid-third facial fracture-stress analysis using a finite element method (FEM)

    Fumikazu Naruse, Yasuaki Ichikawa, Hideki Mizutani, Toshio Kaneda

    Japanese J. of Oral Biology35 ( 4 ) 297 - 311   1993年

  • PARAMETER-IDENTIFICATION BASED ON DUAL BOUNDARY CONTROL CONCEPT

    Y ICHIKAWA

    COMPUTATIONAL MECHANICS : FROM CONCEPTS TO COMPUTATIONS, VOLS 1 AND 2   923 - 930   1993年

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    記述言語:英語   出版者・発行元:A A BALKEMA  

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  • Biomechanical study on mid-third facial fracture-stress analysis using a finite element method (FEM)

    歯科基礎医学会雑誌35 ( 4 ) 297 - 311   1993年

  • 不連続性岩盤における損傷場の逆解析と地下空洞掘削時の変形予測

    土山 茂希, 大上 俊之, 市川 康明

    土木学会論文集 ( 475 ) 49 - 58   1993年

  • Parameter identification based on dual boundary control concept

    Proc. 2nd Asian-Pacific Conf. Computational Mechanics   923 - 930   1993年

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  • A parameter identification procedure as a dual boundary control problem for linear elastic materials

    Soils and Found.32 ( 2 ) 35 - 44   1992年

  • A parameter identification procedure as a dual boundary control problem for linear elastic materials

    Soils and Found.32 ( 2 ) 35 - 44   1992年

  • A boundary element method for identifying orthotropic material parameters

    OHKAMI T, ICHIKAWA Y, KAWAMOTO T

    Int. J. Numer. Anal. Meth. Geomech.15 ( 9 ) 609 - 625   1991年

  • A boundary element method for identifying orthotropic material parameters

    Int. J. Numer. Anal. Meth. Geomech.15 ( 9 ) 609 - 625   1991年

  • A STRAIN LOCALIZATION CONDITION APPLYING MULTIRESPONSE THEORY

    Y ICHIKAWA, T ITO, Z MROZ

    INGENIEUR ARCHIV60 ( 8 ) 542 - 552   1990年

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    記述言語:英語   出版者・発行元:SPRINGER VERLAG  

    The main purpose of this paper is the presentation of a localization condition by using the multi-response theory which gives a comprehensive formulation for the corner theory of Koiter. The effect of a stress Lode angle is considered in the present theory.

    Web of Science

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  • A STRAIN LOCALIZATION CONDITION APPLYING MULTIRESPONSE THEORY

    Y ICHIKAWA, T ITO, Z MROZ

    INGENIEUR ARCHIV60 ( 8 ) 542 - 552   1990年

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    記述言語:英語   出版者・発行元:SPRINGER VERLAG  

    The main purpose of this paper is the presentation of a localization condition by using the multi-response theory which gives a comprehensive formulation for the corner theory of Koiter. The effect of a stress Lode angle is considered in the present theory.

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  • 地盤中の熱伝導と熱輸送の数値解析

    土と基礎37 ( 11 ) 81 - 91   1989年

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  • Deformation and fracturing behaviours of diocontinuous rock mass and damage mechanics

    KAWAMOTO T, ICHIKAWA Y, KYOYA T

    Int. J. Numer. Anal. Meth. Geomech.12 ( 1 ) 1 - 30   1988年

  • Deformation and fracturing behaviours of diocontinuous rock mass and damage mechanics

    Int. J. Numer. Anal. Meth. Geomech.12 ( 1 ) 1 - 30   1988年

  • Incremental theory of plasticity for rock

    Proc. 5th Int. Conf. Numer. Meth. Geomech.   451 - 462   1985年

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  • 岩盤の力学特性評価における損傷テンソルの適用について

    京谷孝史, 市川康明, 川本とし万

    土木学会論文集 ( 358 ) 27 - 35   1985年

  • Incremental theory of plasticity for rock

    Proc. 5th Int. Conf. Numer. Meth. Geomech.   451 - 462   1985年

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  • A continuum theory of coupled seepage and motion problem in saturated poroud metia

    Soils and Found.23 ( 2 ) 165 - 167   1983年

  • A continuum theory of coupled seepage and motion problem in saturated poroud metia

    ICHIKAWA Y, KAWAMOTO T

    Soils and Found.23 ( 2 ) 165 - 167   1983年

  • Numerical analysis of a fully-coupled problem in ground freezing phenomenon

    Proc. 4th Int. Symp. FEM. in Flow Problem   633 - 640   1982年

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  • Numerical analysis of a fully-coupled problem in ground freezing phenomenon

    Proc. 4th Int. Symp. FEM. in Flow Problem   633 - 640   1982年

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  • A one-phase multi-dimensional Stefan problem by the method of variational inequalities

    Int. J. Numer. Meth. Engng14   1197 - 1220   1979年

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  • A one-phase multi-dimensional Stefan problem by the method of variational inequalities

    Int. J. Numer. Meth. Engng14   1197 - 1220   1979年

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  • 変分不等式によるステファン問題

    土木学会論文報告集289   17 - 29   1979年

  • Numerical methods for a two-phase stefan problem by variational inequalities

    Int. J. Numer. Meth. Engng14   1121 - 1239   1979年

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  • Numerical methods for a two-phase stefan problem by variational inequalities

    Int. J. Numer. Meth. Engng14   1121 - 1239   1979年

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Works(作品等)

  • ニアフィールドにおける物質移行挙動の精緻な評価に関する検討

    2006年
    -
    2008年

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  • 結晶質岩を対象とした長期岩盤挙動評価のための理論的研究

    2004年
    -
    2008年

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  • Microscale-Based THMC Characterization of Opalinus Clay

    2003年
    -
    2007年

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  • Microscale-Based THMC Characterization of Opalinus Clay

    2003年
    -
    2007年

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  • 粘土中における拡散吸着現象の物理化学とミクロ・マクロ解析

    2002年
    -
    2005年

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  • 圧密その場X線回折実験によるベントナイトの長期挙動解析

    2002年
    -
    2005年

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  • ベントナイト中の物質移行モデルの高度化研究

    2002年
    -
    2005年

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  • 緩衝材特性評価モデルの高度化に関する基礎研究:均質化法による緩衝材のミクロ・マクロ解析

    1999年
    -
    2003年

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  • ベントナイト緩衝材の長期特性評価に関する研究

    1998年
    -
    2001年

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  • Expert System within Constitutive Theory for Soils with Parameter Calibration as a Nonlinear Back Analysis Problem

    1996年
    -
    2003年

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  • Expert System within Constitutive Theory for Soils with Parameter Calibration as a Nonlinear Back Analysis Problem

    1996年
    -
    2003年

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  • 長期岩盤挙動評価のための微視的観点による基礎的研究

    1994年
    -
    2003年

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  • 逆解析による地盤調査の総合システムの開発

    1994年
    -
    1996年

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  • 温度応力制御によるコンクリートダムの最適設計に関する新技術開発

    1994年
    -
    1996年

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受賞

  • Achievement Award

    2006年  

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  • 業績賞

    2006年  

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    受賞国:日本国

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  • Award for Significant Paper, International Association for Computer Methods and Advances in Geomechanics

    1994年  

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  • 形状記憶医用学会村松力記念学術功労賞

    1990年  

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    受賞国:日本国

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共同研究・競争的資金等の研究

  • Microscale properties of mudstone and micro/macro analysis

    2003年 - 2007年

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    資金種別:競争的資金

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  • 泥岩の微視物性とミクロ・マクロ挙動

    2003年 - 2007年

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    資金種別:競争的資金

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  • Physics and chemistry of clay transport phenomena

    1999年

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    資金種別:競争的資金

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  • 粘土の物理化学と物質移動

    1999年

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    資金種別:競争的資金

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  • Micro-to-macro analysis by the molecular dynamics and homogenization method applied to geomaterials

    1996年

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    資金種別:競争的資金

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  • 分子動力学法と均質化法による地盤材料のミクロ・マクロ解析

    1996年

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    資金種別:競争的資金

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