Researcher Database

Yoshiaki Fujii
Faculty of Engineering Sustainable Resources Engineering Geoenvironmental Engineering
Professor

Researcher Profile and Settings

Affiliation

  • Faculty of Engineering Sustainable Resources Engineering Geoenvironmental Engineering

Job Title

  • Professor

Degree

  • Ph. D.(Hokkaido University)

URL

J-Global ID

Research Interests

  • Energy in future   Future of human society   Rock Mechanics   Lies in climate change   Earthquake Prediction   

Research Areas

  • Energy / Earth resource engineering, energy science

Association Memberships

  • Seismological Society of America   北海道土木技術会トンネル研究委員会   開発技術研究会   International Society for Rock Mechanics   土木学会   資源・素材学会   

Research Activities

Published Papers

  • Yoshiaki Fujii, Shiori Saito, Teppei Oshima, Jun ichi Kodama, Daisuke Fukuda, Shokichi Sakata, Kagemi Uchida, Hiroyuki Matsumoto, Anjula B.N. Dassanayake
    International Journal of Rock Mechanics and Mining Sciences 131 1365-1609 2020/07 [Refereed][Not invited]
     
    © 2020 Elsevier Ltd Slaking is a well-known process, in which the surface of rock masses consisting of rocks such as mudstone, shale, etc. show rapid and complete disintegration when they are subjected to drying and then wetting with fresh water. On the other hand, dried sandstones even if they contain clay minerals such as smectite, etc., usually do not exhibit complete disintegration when they are soaked in fresh water. Instead, they usually show a strength decrease. Their slaking durability is tested by rotating them in a drum which is partially immersed in fresh water and eventually measuring the decrease in weight. On the other hand, it was found that some of the Paleogene sandstones from Kushiro Coal Mine in Japan, were completely disintegrated when they were immersed in fresh water followed by drying, but they were not collapsed when saline water was used instead of the fresh water. It was also shown that sandstones containing calcite did not show the complete breakdown even in fresh water. To understand the complete collapse of sandstones in fresh water and prevention of the collapse by salt water, sandstones sampled from Neogene dikes and Cretaceous at the mine were immersed in pure and salt water with Shikotsu welded tuff for comparison. Only dike sandstones showed a complete collapse in pure water and 3% salt water. Dike sandstone further showed severe time-dependent damage in salt water whose salinity was less than 7%. The results were explained by the dissolution of halite, swelling pressure of montmorillonite, osmotic pressure, etc.
  • Development of a Numerical Simulator for 3-D Dynamic Fracture Process Analysis of Rocks Based on Hybrid FEM-DEM Using Extrinsic Cohesive Zone Model
    Daisuke FUKUDA, Erina NIHEI, Sang-Ho CHO, Sewook OH, Yoshitaka NARA, Jun-ichi KODAMA, Yoshiaki FUJII
    Zairyo 69 (3) 228 - 235 2020/03 [Refereed][Not invited]
  • Daisuke Fukuda, Mojtaba Mohammadnejad, Hongyuan Liu, Qianbing Zhang, Jian Zhao, Sevda Dehkhoda, Andrew Chan, Jun ichi Kodama, Yoshiaki Fujii
    Rock Mechanics and Rock Engineering 53 (3) 1079 - 1112 0723-2632 2020/03/01 [Refereed][Not invited]
     
    © 2019, Springer-Verlag GmbH Austria, part of Springer Nature. As a state-of-the-art computational method for simulating rock fracturing and fragmentation, the combined finite-discrete element method (FDEM) has become widely accepted since Munjiza (2004) published his comprehensive book of FDEM. This study developed a general-purpose graphic-processing-unit (GPGPU)-parallelized FDEM using the compute unified device architecture C/C ++ based on the authors’ former sequential two-dimensional (2D) and three-dimensional (3D) Y-HFDEM IDE (integrated development environment) code. The theory and algorithm of the GPGPU-parallelized 3D Y-HFDEM IDE code are first introduced by focusing on the implementation of the contact detection algorithm, which is different from that in the sequential code, contact damping and contact friction. 3D modelling of the failure process of limestone under quasi-static loading conditions in uniaxial compressive strength (UCS) tests and Brazilian tensile strength (BTS) tests are then conducted using the GPGPU-parallelized 3D Y-HFDEM IDE code. The 3D FDEM modelling results show that mixed-mode I–II failures are the dominant failure mechanisms along the shear and splitting failure planes in the UCS and BTS models, respectively, with unstructured meshes. Pure mode I splitting failure planes and pure mode II shear failure planes are only possible in the UCS and BTS models, respectively, with structured meshes. Subsequently, 3D modelling of the dynamic fracturing of marble in dynamic Brazilian tests with a split Hopkinson pressure bar (SHPB) apparatus is conducted using the GPGPU-parallelized 3D HFDEM IDE code considering the entire SHPB testing system. The modelled failure process, final fracture pattern and time histories of the dynamic compressive wave, reflective tensile wave and transmitted compressive wave are compared quantitatively and qualitatively with those from experiments, and good agreements are achieved between them. The computing performance analysis shows the GPGPU-parallelized 3D HFDEM IDE code is 284 times faster than its sequential version and can achieve the computational complexity of O(N). The results demonstrate that the GPGPU-parallelized 3D Y-HFDEM IDE code is a valuable and powerful numerical tool for investigating rock fracturing under quasi-static and dynamic loading conditions in rock engineering applications although very fine elements with maximum element size no bigger than the length of the fracture process zone must be used in the area where fracturing process is modelled.
  • Jun ichi Kodama, Yoshitaka Mitsui, Syohei Hara, Daisuke Fukuda, Yoshiaki Fujii, Atsushi Sainoki, Murat Karakus
    Cold Regions Science and Technology 168 0165-232X 2019/12 [Refereed][Not invited]
     
    © 2019 Elsevier B.V. A series of uniaxial compression and creep tests were performed on dry and wet specimens of Shikotsu welded tuff at −20 °C (−4 °F) to examine the time-dependence of the mechanical behavior of frozen rock. The impact of the water content of the specimens on the time-dependence of mechanical behavior was also investigated. The uniaxial compressive strengths (UCSs) of the frozen wet specimens strongly depended on the loading rate, and were greater than those of the frozen dry specimens at strain rates greater than 4.2 × 10−5 s−1. However, the creep lives of the frozen wet specimens were shorter than those of the frozen dry specimens at stress levels of less than 13.4 MPa (52% of the UCSs of the frozen wet specimens). Deformation behavior induced by pore ice was observed in the frozen wet specimens. The stress–strain behavior transitioned from brittle to ductile as the strain rate increased, and the ratio of the tertiary creep region was relatively larger. The strains of the frozen wet specimens were significantly larger than the frozen dry specimens. These results demonstrated that understanding the time-dependent deformation of frozen rock is crucial for the assessment of the long-term stability of rock slopes in cold regions, as pore ice strongly affected the failure process of the frozen wet specimens.
  • Fukuda Daisuke, Mohammadnejad Mojtaba, Liu Hongyuan, Dehkhoda Sevda, Chan Andrew, Cho Sang-Ho, Min Gyeong-Jo, Han Haoyu, Kodama Jun-ichi, Fujii Yoshiaki
    INTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS 43 (10) 1797 - 1824 0363-9061 2019/07 [Refereed][Not invited]
  • Advances in Civil Engineering 2019/02 [Refereed][Not invited]
  • P. Sinkala, M. Nishihara, Y. Fujii, D. Fukuda, J. Kodama, E. Chanda
    53rd U.S. Rock Mechanics/Geomechanics Symposium 2019 [Refereed][Not invited]
     
    Copyright 2019 ARMA, American Rock Mechanics Association. Mufulira mine has been in operation since 1933. The mine is situated in the Copperbelt region of Zambia, which is predominantly rich in copper and cobalt mineralization. Since the beginning of 1970s, the mine has been recording incidents of rockbursts and applying various efforts to find mitigation measures for rockbursts. Recently, an M2.8 rockburst occurred in the mining drive at 1440 meter level underground on 16 January, 2018. In order to understand the mechanism of the rockburst, three major steps were taken. These were field geotechnical investigation, followed by uniaxial compression tests, and finally stress analysis. Under field investigations, scan-line mapping of joints indicated few major joint sets in the surrounding rock mass to the rockburst location. Stress analysis showed very high stresses in the chain pillars and low stress concentration at the rockburst site during initial stages of mining. But later, stress levels gradually increased with mining. It was therefore concluded that fracturing of the relatively intact rock mass around the mining drive under gradual stress increase by mining could be the cause of the rockburst.
  • S. Boeut, Y. Fujii, J. Kodama, D. Fukuda, A. B.N. Dassanayake
    53rd U.S. Rock Mechanics/Geomechanics Symposium 2019 [Refereed][Not invited]
     
    Copyright 2019 ARMA, American Rock Mechanics Association. A persistent increase in the permeability of a rock mass caused by transient stress disturbances, when they exist, can explain the change in groundwater level as well as the petroleum production by seismic waves in the far-field. However, it has yet to be clarified whether the transient stress disturbances induce an increase or decrease in the rock permeability. To clarify the effects of transient stress disturbances on the rock permeability, permeability measurements were carried out on intact and triaxially fractured Shikotsu welded tuff, both before and after the occurrence of axial stress or pore pressure transient disturbances. Based on the experimental results, both types of stress disturbances showed an increasing effect on the permeability for fractured rocks. However, only the pore pressure disturbances showed an increasing effect for intact rocks. It can be estimated that rock masses consisting of glassy pyroclastic rock may exhibit an increase in the permeability through disturbances in the transient stress.
  • Sophea Boeut, Teppei Oshima, Yoshiaki Fujii, Jun Ichi Kodama, Daisuke Fukuda, Hiroyuki Matsumoto, Kazumi Uchida, Anjula B.N. Dassanayake
    Advances in Civil Engineering 2019 1687-8086 2019 [Refereed][Not invited]
     
    © 2019 Sophea Boeut et al. A persistent increase in the permeability of rock mass caused by transient stress disturbances, if present, could explain the variation in the groundwater level in far fields, increase in petroleum production caused by earthquakes or artificial vibrations in enhanced oil recovery, and induction of earthquakes by seismic waves in intermediate and far fields. However, it has not been verified whether the transient stress disturbances induce an increase or decrease in the rock permeability. In this study, the permeability values of intact and triaxially fractured Kushiro Cretaceous sandstone and Shikotsu welded tuff were measured before and after transient axial stress or pore pressure disturbances to clarify the effects of transient stress disturbances on rock permeability. According to the experimental results, the stress disturbances showed either decreasing or increasing effects on the permeability depending on the rock type and experimental conditions. However, when focusing on the fractured rocks rather than the intact ones, which would be more important in field applications, the argillaceous Kushiro Cretaceous sandstone mainly exhibited decreasing effects and the glassy Shikotsu welded tuff mainly exhibited increasing effects.
  • Umali M. Yasidu, Yoshiaki Fujii, Jun Ichi Kodama, Daisuke Fukuda, George J. Maneya, Johnson Dandadzi, Anjula B.N. Dassanayake
    Advances in Civil Engineering 2019 1687-8086 2019 [Refereed][Not invited]
     
    © 2019 Umali M. Yasidu et al. To develop affordable countermeasures against the roof falls, the accident records of Mchenga Mine were investigated as the first step. Based on the accident records, it was found that roof falls occurred most in April and May. Humidity measurements were taken both in the underground mine and at surface, and humidity peak appeared in April. The accident occurrence and the underground humidity had a positive correlation in which no roof falls could be expected under a humidity of less than a certain value. Effect of humidity on the indirect tensile strength of the rock samples collected from the mine was investigated, and it showed that the indirect tensile strength decreased with humidity. The diffusion coefficient was measured for the rock samples collected from Mchenga Mine as well as from Kaziwiziwi Mine, and the migration of water vapor into rock mass in the roof was calculated for Mchenga case. It was clarified that the weakening of tensile strength was transmitted upward at several centimeters per day from the immediate roof. This could explain the slight difference of the accident peak in April and May from the humidity peak in April. Introducing fresh and dry outside air, if possible, will not only improve the working environment but also contribute to a decrease in roof falls.
  • Li, S, Huo, R, Fujii, Y, Ren, D, Song, Z
    Int. J. Rock Mech. Min. Sci. 122 2019 [Refereed][Not invited]
  • Y. Fujii, M. Makasi, J. Kodama, D. Fukuda, K. Goto, S. Kumakura, M. Kanaoka, A. B.N. Dassanayake
    Tunnelling and Underground Space Technology 82 148 - 155 0886-7798 2018/12 [Refereed][Not invited]
     
    © 2018 Elsevier Ltd This paper proposed Tangent Modulus Method (TMM) which is an improved oriented core method to determine in-situ rock stresses. In this approach, the cylindrical specimens prepared along different directions from thick core samples were uniaxially compressed twice to a given stress level. The stress value of the bending point in the first loading cycle of the stress-tangent modulus curve is considered as the normal component of the in-situ rock stress along the drilled direction of the specimen. Four types of rocks from soft porous tuff and sandstone to hard crystalline granite was investigated to evaluate the potential of this method. The effects of changes in strain rate, temperature, water content, confining and pore pressure, and stresses larger than the preload on the stress value of the bending point were experimentally investigated on preload specimens to investigate their influence on TMM. Comparison of the stress measurement results by TMM and an overcoring method at AK tunnel in Hokkaido, Japan was also performed to validate the TMM.
  • Yoshiaki Fujii, Yoshihisa Ichihara, Hiroyuki Matsumoto, Jun Ichi Kodama, Daisuke Fukuda, Anjula B.N. Dassanayake
    Scientific Reports 8 (1) 2018/12/01 [Refereed][Not invited]
     
    © 2018, The Author(s). The amount of water drainage from Kushiro Coal Mine in Hokkaido, Japan decreased on the day of all M ≥ 7.5 earthquakes with epicenters within 300 km of the mine during the monitoring period and increased after these earthquakes. This is a valuable finding which would give us a clue to understand pre- and post-seismic rockmass behaviors and contribute for progress in earthquake prediction in future.
  • Yoshiaki Fujii, Morteza Sheshpari, Jun ichi Kodama, Daisuke Fukuda, Anjula B.N. Dassanayake
    Sustainability (Switzerland) 10 (6) 2018/06/07 [Refereed][Not invited]
     
    © 2018 by the authors. Catastrophic volcanic eruptions, large earthquakes beneath big cities, or giant earthquakes at subduction zones are apparently the biggest problems facing the sustainability of human society. However, imminent prediction methods for these events have never been established, except that volcanic eruptions can only be predicted by exceptional efforts by dedicated researchers. Even if a prediction method has been established, the method cannot significantly reduce infrastructure damage, although it could slightly reduce the number of fatalities. On the other hand, prevention of eruptions or earthquakes could significantly reduce, not only the number of fatalities, but also infrastructure damage. Therefore, the authors propose (1) gradual energy release by supercritical power generation to prevent catastrophic eruptions; (2) gradual seismic energy release by injecting water into seismic sources to prevent large earthquakes beneath big cities; and (3) exploding existing nuclear warheads underground to prevent giant earthquakes at subduction zones. Necessary technical developments, costs, risks, and problems will also be explained.
  • 児玉淳一, 立川多久登, 中良介, 濱中晃弘, 板倉賢一, 出口剛太, 福田大祐, 藤井義明
    J. MMIJ 134 (7) 91 - 98 2018 [Refereed][Not invited]
  • Morteza Sheshpari, Yoshiaki Fujii, Takuya Tani
    TUNNELLING AND UNDERGROUND SPACE TECHNOLOGY 64 61 - 73 0886-7798 2017/04 [Refereed][Not invited]
     
    Humans can inhabit other planets in future by advancement in science and technology, starting by closest ones and moving to farther planets. There are some projects underway currently for human settlement on Mars such as Mars-one project or new proposals by NASA. In this paper, possibility of creating and using underground structures in Mars for sheltering humans against harsh environment and dangerous rays goes under investigation. Primary locations such as Arsia Mons for early settlement on Mars was investigated providing its appropriate conditions. Numerical analysis for tunneling to create underground space was conducted considering different spatial orientation of main discontinuities such as fault and joints in Martian gravity. It was inferred that tunneling in near surface Martian rocks is not susceptible to major failures and instabilities. Frozen water in Mars climate, and low gravity result in lower amounts of required cohesion value to keep tunneling structure stable in different scenarios of discontinuities in Martian rocks. It was concluded that underground structures are among the best options for residing humans on Mars and sheltering them against harsh climate by providing insulation and creating enough thickness of burden rock mass against dangerous cosmic and solar rays. (C) 2017 Elsevier Ltd. All rights reserved.
  • Ryota Moriya, Daisuke Fukuda, Jun-ichi Kodama, Yoshiaki Fujii
    OPERATIONAL AND ENVIRONMENTAL MINE HEALTH AND SAFETY PRACTICE AND INNOVATION 121 - 126 2016 [Refereed][Not invited]
     
    In open-cut limestone mines in Japan, huge rock slopes with a geological boundary between limestone and bedrock have been formed by mining activities. In addition, latent sliding plane near the toe of the slopes may be formed through the development of damaged zones with an increase in size of the rock slope. It has been reported that inelastic time-dependent sliding deformation of rock slopes along both the geological boundary and the latent sliding plane can occur. In this case, one of the countermeasures to suppress sliding deformation is an application of rock buttress to the slope surface where the sliding is taking place. However, the effect of rock buttress on reduction of the rock slope sliding has not yet been clarified. In this paper, the effect of rock buttress on reduction of the rock slope sliding is discussed based on a 2-dimensional finite element analysis using a non-linear visco-elastic model. The results indicate that (i) the degree of deterioration of sliding plane at the time of the application of rock buttress significantly affects the expected life of rock slope, (ii) there is an optimum height for rock buttress,, (iii) larger Young's modulus of rock buttress results in a longer expected life of rock slope, and (iv) the balance of increase and decrease of normal and shear stresses on the sliding plane by buttress is important and the obtained results can be changed by the difference of friction angle and the geometry of the sliding plane.
  • Ilyas Khurshid, Yoshiaki Fujii, Jonggeun Choe
    JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING 135 240 - 245 0920-4105 2015/11 [Refereed][Not invited]
     
    Reservoir compaction and pore collapse are induced with fluids (oil, gas, and water) productions. They are responsible for both recovery and environmental problems. Our objective is to develop a generic integrated framework for reservoir compaction to determine optimal time ranges of fluids (CO2 or water) injection in a reservoir for increasing oil recovery and their storage. The framework consists of a model with a methodology. We derive the model using the concept of body-centered pores in a cubic lattice at microscopic level. The model describes the relationship between porosity and stresses, and estimates reservoir compaction as a function of fluid withdrawal, time, and stresses. On the basis of the model developed, we propose a methodology named failure-line method to determine the critical point of irreversible brittle pore collapse. Thus, the best fluid injection time range is before touching this critical point. We use inversion analysis to determine, compare and validate our results with experimental and field data available, and found a good match. As a result, the developed model and methodology can be an efficient and cost effective tool to investigate the effect of production on reservoir compaction, variation in porosity, and to determine an optimal time range for fluid injection. The model assumes that there are no consistent capillary and gravity forces. Crown Copyright (C) 2015 Published by Elsevier B.V. All rights reserved.
  • A. K. M. Badrul Alam, Yoshiaki Fujii, Daisuke Fukuda, Jun-ichi Kodama, Katsuhiko Kaneko
    PURE AND APPLIED GEOPHYSICS 172 (10) 2871 - 2889 0033-4553 2015/10 [Refereed][Not invited]
     
    Triaxial compression tests were carried out on Shikotsu welded tuff, Kimachi sandstone, and Inada granite under confining pressures of 1-15 MPa at 295 and 353 K. The permeability of the tuff declined monotonically with axial compression. The post-compression permeability became smaller than that before axial compression. The permeability of Kimachi sandstone and Inada granite declined at first, then began to increase before the peak load, and showed values that were almost constant in the residual strength state. The post-compression permeability of Kimachi sandstone was higher than that before axial compression under low confining pressures, but lower under higher confining pressures. On the other hand, the permeability of Inada granite was higher than that before axial compression regardless of the confining pressure values. For the all rock types, the post-compression permeability at 353 K was lower than at 295 K and the influence of the confining pressure was less at 353 K than at 295 K. The above temperature effects were observed apparently for Inada granite, only the latter effect was apparent for Shikotsu welded tuff, and they were not so obvious for Kimachi sandstone. The mechanisms causing the variation in rock permeability and sealability of underground openings were discussed.
  • A. B. N. Dassanayake, Yoshiaki Fujii, Daisuke Fukuda, Jun-ichi Kodama
    JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING 131 70 - 79 0920-4105 2015/07 [Refereed][Not invited]
     
    This paper is devoted to the experimental investigation of effective stress coefficient for peak and residual strengths of saturated Kimachi sandstone. Authors have described the Modified Failure Envelope Method (MFEM), which can be used to obtain the effective stress coefficients for peak and residual strengths (alpha(-Peak) and alpha(-Residual)). The effective stress coefficients for intact and fractured Kimachi sandstone (alpha(-Biot's) and alpha(-Fractured)) were also evaluated using conventional methods, and the data were compared with the coefficient values obtained by MFEM for the peak and residual strengths. The effective stress coefficient for intact rock, alpha(-Biot's) decreased with increasing confining pressure, and was in the range 1 > alpha(-Biot's) > 0.8. The effective stress coefficient for fractured rock, alpha(-Fractured), was larger than that for intact rock and was close to unity. The effective stress coefficient calculated for peak strengths, alpha(-Peak), using both the single and multistage MFEMs, decreased with increasing effective confining pressure and was in the range 0.8 > alpha(-Peak) > 0.4. For residual strength states, effective stress coefficient, alpha(-Residual), was between the peak strength value and that for intact rock. Based on the results, multistage MFEM is suitable for obtaining an effective stress coefficient for the peak strength, alpha(-Peak). An equation to obtain the effective stress coefficient from total confining pressure and pore pressure, and a method to choose the coefficients for elastic stress analyses and failure evaluations for intact rock structures or structures in rock mass were proposed. (C) 2015 Elsevier B.V. All rights reserved.
  • Evaluation of 3-D Strain Distribution in Lignite Based on Image Analysis
    D. Fukuda, M. Maruyama, J. Kodama, Y. Fujii, N. Aramaki, K. Kaneko, Y. Nara
    ISRM Congress 2015 (The 13th. International Congress of Rock Mechanics) 394  2015 [Refereed][Not invited]
  • 荒牧憲隆, 玉村修司, 田中翔, 川崎了, 藤井義明, 金子勝比古
    地盤工学ジャーナル 10 (3) 391 - 401 2015 [Refereed][Not invited]
  • Najib, Daisuke Fukuda, Jun-Ichi Kodama, Yoshiaki Fujii
    MATERIALS TRANSACTIONS 56 (8) 1159 - 1168 1345-9678 2015 [Refereed][Not invited]
     
    This paper discusses an investigation of mining-induced elastic deformation of a cut rock slope formed in a mountain-type mine using a two-dimensional finite element method. The horizontal elastic deformation mechanism is discussed, including the effects of the Poisson's ratio, slope angle and progression of the excavation. The results show a clear dependence of the deformation modes characterized by extension, contraction or shear distortion of rock mass, on these three effects, in which the direction of rock movement at the surface due to excavation was opposite. Four effects contribute to the deformation mechanism in mountain-type mines: the Poisson effect (PE), the distributed load effect (DLE), bending effects and shear distortion. Forward surface displacement of the cut rock slope was found to occur during the early stages of excavation due to the release of horizontal compressive stresses due to bending effects around the middle of the mountaintop. As the excavation progresses, forward or backward horizontal surface displacement was found to occur due to PE or DLE, respectively, which depends on the Poisson's ratio in the subsequent stages of excavation. Asymmetric stress release due to excavation affects the horizontal deformation of the mountain, and induces a moment enhancing the backward displacement due to shear distortion. It should be noted that the direction of the surface displacement of the rock slope could change from forward to backward as the excavation progresses, even though the rock slope may be stable. This is very important in the interpretation of surface displacement monitoring using the Automated Polar System and/or Global Positioning System. In the interpretation of the internal displacement measured using extensometers, we should consider extension during the early stages of excavation, followed by slight contraction during the latter stages, as a sign of a stable cut rock slope in a mountain type mine.
  • Jun-Ichi Kodama, Takanori Azehara, Daisuke Fukuda, Yoshiaki Fujii
    Zairyo/Journal of the Society of Materials Science, Japan 63 (3) 219 - 226 1880-7488 2014 [Refereed][Not invited]
     
    Fracture processes of argillaceous schist and granite subjected to freeze-thaw cycles were investigated based on their deformation behaviors. It was found that argillaceous schist showed apparent anisotropy in deformation. Significant extensile strain was observed in the direction perpendicular to the cleavage plane around -3°C in freezing process on the water-saturated specimen, followed by extensile plastic strain at the end of the cycle. No apparent extension and anisotropy were found on the water-saturated specimen of granite, but decrease in contraction rate was seen at -3°C in freezing process with AE activity. The extensile plastic strain of both rocks gradually increased with the number of freeze-thaw cycles, but magnitude of the plastic strain on argillaceous schist was much greater than that of granite. These results indicate that there might be common mechanism in fracture process between both rocks, but significant differences in deterioration rate. Deterioration of argillaceous schist is much faster because fracture mainly develops by extension of well-developed cleavage in the rock. It was concluded that weak plane such as cleavage strongly affected deterioration of rocks by freeze-thaw cycle. © 2014 The Society of Materials Science, Japan.
  • A. K. M. Badrul Alam, Masaki Niioka, Yoshiaki Fujii, Daisuke Fukuda, Jun-ichi Kodama
    INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES 65 49 - 61 1365-1609 2014/01 [Refereed][Not invited]
     
    Triaxial tests were conducted on three different rocks, under confining pressures of 1-15 MPa at 295 K using an ultra-compact triaxial cell. The samples were held for 24 h under the target consolidation pressure, and then constant strain-rate compression was applied measuring permeability. The structural changes were measured by thin section image analysis and micro-focus X-ray computed tomography. For the Shikotsu welded tuff, the permeability decreased monotonously with axial compression, mainly due to pore collapse. For the Kimachi sandstone, the permeability first decreased with increasing axial stress, then began to increase when the total lateral strain recovered its value before the application of confining pressure, and then maintained an almost constant value in the post-peak region. The minimum and final permeability decreased with increasing confining pressure mainly due to compaction and large plastic deformation of clay cementing materials. For the lnada granite, the tendency of permeability change during axial compression was almost the same as for the Kimachi sandstone. The final permeability was larger than that before compression, and the permeability decreased with smaller confining pressure mainly due to a decrease in the number and width of rupture planes and the absence of axial cracks from biotite. The permeability, however, increased under larger confining pressures mainly due to the formation of subrupture planes caused by the high stress concentration at the rough and stiff rupture plane under large confining pressure. (C) 2013 Elsevier Ltd. All rights reserved.
  • A. K. M. B. Alam, Y. Fujii, D. Fukuda, M. Niioka
    ROCK ENGINEERING AND ROCK MECHANICS: STRUCTURES IN AND ON ROCK MASSES 131 - 136 2014 [Refereed][Not invited]
     
    Triaxial compression tests were carried out at 295K and 353K under confining pressure of 1-15 MPa for Shikotsu welded tuff, Kimachi sandstone and Inada granite. The samples were kept for 24 hr consolidation and then axial compression was applied measuring permeability. Permeability decreased monotonously for Shikotsu welded tuff. The permeability decreased first, began to increase before peak load and showed almost constant value in the residual strength state for Kimachi sandstone and Inada granite. Permeability decreased by failure for Shikotsu welded tuff. It increased due to failure under low confining pressures but decreased under high confining pressures for Kimachi sandstone. It increased due to failure for Inada granite. The permeability at 353K was lower than that at 295K for all of the three types of rock. The mechanisms of the permeability decrease are also shown.
  • A. B. N. Dassanayake, Y. Fujii
    ROCK ENGINEERING AND ROCK MECHANICS: STRUCTURES IN AND ON ROCK MASSES 155 - 160 2014 [Refereed][Not invited]
     
    Kimachi sandstone and Shikotsu welded tuff were tested in single and multistage triaxial tests to determine the Biot's effective stress coefficient (alpha). Pure water saturated 30 mm in diameter and length of 60 mm cylindrical test specimens were introduced for triaxial compression, with strain rate at 10(-5) s(-1). For Kimachi sandstone, alpha value for peak strength decreased with effective confining pressure. a values for residual strength were almost constant and larger than the case of peak strength. For Shikotsu welded tuff, only two data points were obtained for peak strength due to pore collapse and alpha value for residual strength decreased with effective confining pressure. The multistage test has given a fair evaluation of the coefficient for peak strength of Kimachi snadstone. Number of specimens and variation from specimen to specimen can be reduced by using multistage tests although further considerations are required to obtain the coefficient for residual strength.
  • J. Kodama, T. Miyamoto, S. Kawasaki, Y. Fujii, K. Kaneko, P. Hagan
    INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES 63 1 - 11 1365-1609 2013/10 [Refereed][Not invited]
     
    A method to evaluate regional stress state and Young's modulus by analyzing the mining-induced deformation of ground is proposed. The effect of changes in regional strain state due to tectonic plate motion can be accounted for using the proposed method. Mining-induced deformation can manifest itself as changes in ground surface geometry resulting from mining activity. There are three underlying factors that can contribute to the deformation, these being: displacement induced by the effect of gravity; displacement induced by the effect of horizontal regional strain; and, incremental change in the horizontal regional strain. Both regional strain and Young's modulus can be simultaneously estimated, because the displacement induced by the regional strain is independent of the Young's modulus and the displacement induced by the gravity is inversely proportional to the Young's modulus. The relative displacement arising from the mining excavation at the Torigatayama limestone mine in Japan has been measured by GPS. Both the regional stress state and Young's modulus were estimated by back analysis of the relative displacement using a 3-D finite element method. It was shown that back analysis based on changes in distance between the measurement points provides a more reliable estimation than that could be achieved based on the direct relative displacement. (C) 2013 Elsevier Ltd. All rights reserved.
  • J. Kodama, T. Goto, Y. Fujii, P. Hagan
    INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES 62 (3) 1 - 13 1365-1609 2013/09 [Refereed][Not invited]
     
    The effects of water content, temperature and loading rate on the strength and failure process of rock at sub-zero temperatures were investigated and are presented in this paper. Over the range of temperatures studied there was little change observed in the properties of dry rock. The presence of water in the rock, however, resulted in a marked increase in rock strength and the fracture initiation stress. Rock strength increased with amount of water present and the rate of load application, with the effect being exacerbated at the colder temperatures. Interestingly, the changes in strength were not uniform as there was a greater rate of increase in the tensile strength of rock with temperature than compressive strength. It is postulated that these changes in mechanical properties may be explained in part by a reduction in the stress concentration within the interstitial spaces and cracks of the rock samples tested. (C) 2013 Elsevier Ltd. All rights reserved.
  • 児玉淳一, 高坂恒輔, 福田大祐, 藤井義明
    J. MMIJ 129 (7) 418 - 424 2013 [Refereed][Not invited]
  • 三井善孝, 児玉淳一, 原翔平, 菅原隆之, 福田大祐, 藤井義明
    J. MMIJ 129 (7) 425 - 432 2013 [Refereed][Not invited]
  • 藤井義明, 児玉淳一, 福田大祐
    J. MMIJ 129 (7) 467 - 471 2013 [Refereed][Not invited]
  • 児玉淳一, 原翔平, 三井善孝, 藤井義明
    J, MMIJ 129 (1) 21 - 28 2013 [Refereed][Not invited]
  • 谷卓也, 青木智幸, 小川豊和, 武田均, 藤井義明
    J. MMIJ 128 (3) 113 - 120 2012/03 [Refereed][Not invited]
  • FUJII Yoshiaki
    Journal of MMIJ : Journal of the Mining and Materials Processing Institute of Japan 資源・素材学会 128 (4) 218 - 223 1881-6118 2012/03 [Refereed][Not invited]
  • KUMAKURA Satoshi, ISHIJIMA Yoji, FUJII Yoshiaki, KODAMA Jun-ichi
    Journal of MMIJ : Journal of the Mining and Materials Processing Institute of Japan 資源・素材学会 128 (4) 163 - 172 1881-6118 2012/03 [Refereed][Not invited]
  • Y. Fujii, T. Sugawara, J. Kodama, Y. Ishijima, T. Kiyama, M. Takada, Y. Ichihara, S. Kumakura, T. Narita, M. Sawada, E. Nakata
    HARMONISING ROCK ENGINEERING AND THE ENVIRONMENT 975 - 978 2012 [Refereed][Not invited]
     
    95 abandoned old roadways up to 50 years old and 300m deep were observed at Kushiro Coal Mine. Large plastic deformations as roof deflection and/or floor heave closed most roadways although a few roadways were remain open. Such in-situ measurements as Rayleigh wave velocity, permeability etc. were carried out. Rayleigh wave velocity in the closed roadway was approx. half the virgin rock mass. Permeability of closed roadway was 40 times greater than that for virgin rock mass. This suggests that 1/40 sealability can be expected even a rock cavern in clastic rocks completely collapsed. This would be much better than rock cavern in crystalline rocks in which much less sealability is expected when completely collapsed.
  • Yoshiaki Fujii, Yoji Ishijima, Yoshihisa Ichihara, Tamotsu Kiyama, Satoshi Kumakura, Michihiko Takada, Takayuki Sugawara, Takashi Narita, Jun-ichi Kodama, Masataka Sawada, Eiji Nakata
    INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES 48 (4) 585 - 596 1365-1609 2011/06 [Refereed][Not invited]
     
    The objective of this research is to clarify the mechanical properties and self-healing ability of the Excavation Damaged Zone (EDZ) around rock caverns in clastic-rock. Observations of nearly one hundred closed roadways up to fifty years old, which can be regarded as very severe EDZs with no initial sealability and are up to 300 m deep in clastic-rock, were made at the Kushiro Coal Mine, Japan, to accomplish the objective. Most old roadways were closed, though a few remain open. Closure of old roadways was mainly due to roof deflection and/or floor heave. Large plastic deformations dominated; however, severe fractures were seldom observed in closed old roadways. Rayleigh wave velocity and hydraulic conductivity in the closed old roadways were in the range of 0.3-1.2 km/s and 5 x 10(-7)-1 x 10(-7) m/s, respectively, and those in EDZ and EdZ (Excavation disturbed Zone) around recently excavated roadways were 1.1-1.8 km/s and 1 x 10(-8)-5 x 10(-8) m/s, respectively. The extent of EDZ around the present tailgate was in the range of 1-5 m. Mechanical excavation and prevention from water are suggested as the key points for long-term maintenance of rock repositories. Pressurization from inside the cavern to decrease the permeability of EDZ is proposed for maintenance of rock repositories in medium-hard clastic-rock masses at similar depths for long periods. (C) 2011 Elsevier Ltd. All rights reserved.
  • Yoshiaki Fujii
    JOURNAL OF ATMOSPHERIC AND SOLAR-TERRESTRIAL PHYSICS 73 (5-6) 643 - 652 1364-6826 2011/04 [Refereed][Not invited]
     
    This study suggests that the cause of the stagnation in global warming in the mid 20th century was the atmospheric nuclear explosions detonated between 1945 and 1980. The estimated GST drop due to fine dust from the actual atmospheric nuclear explosions based on the published simulation results by other researchers (a single column model and Atmosphere-Ocean General Circulation Model) has served to explain the stagnation in global warming. Atmospheric nuclear explosions can be regarded as full-scale in situ tests for nuclear winter. The non-negligible amount of GST drop from the actual atmospheric explosions suggests that nuclear winter is not just a theory but has actually occurred, albeit on a small scale. The accuracy of the simulations of GST by IPCC would also be improved significantly by introducing the influence of fine dust from the actual atmospheric nuclear explosions into their climate models; thus, global warming behavior could be more accurately predicted. (C) 2011 Elsevier Ltd. All rights reserved.
  • Azania Mufundirwa, Yoshiaki Fujii, Nariaki Kodama, Jun-ichi Kodama
    COLD REGIONS SCIENCE AND TECHNOLOGY 65 (3) 488 - 500 0165-232X 2011/03 [Refereed][Not invited]
     
    In this paper, natural rock slope deformation across fractures predominantly in a chert rock mass was monitored using six surface fracture displacement sensors, and the deformations arising from thermal stresses were predicted using (5 m x 5 m) two-dimensional (2D) finite element (FE) plane strain analysis coupled with a model for rock mass expansion due to freezing of pore water. A new and simple method to minimize displacement proportional to temperature (due to thermal response of chert rock mass and sensor) was proposed. By applying the method, the corrected displacement, u', can be well recognized. Under u', clear rock mass movement, which could be related to fracture growth, was observed. In addition, progressive fracture opening and closure were noted. Results from this study indicate insignificant influences of weather conditions on fracture/rock mass movement. Furthermore, under numerical analysis (FE), in the rock mass model (with 1-m deep fracture), tensile stresses that were large enough to induce fracture growth appeared at the fracture tip when temperature lowered. And in the rock slope model (with 1-m deep fracture), small tensile stresses, which were sufficient to cause fracture growth along the planes of weakness, were observed. This research suggests that freezing effects on deformation of chert rock mass are insignificant, and we tentatively suggest that thermal fatigue predominantly caused the permanent fracture deformations. (C) 2010 Elsevier B.V. All rights reserved.
  • KODAMA Jun-ichi, NAKAYA Masashi, NARA Yoshitaka, GOTO Tatsuhiko, FUJII Yoshiaki, KANEKO Katsuhiko
    Journal of MMIJ 資源・素材学会 127 (3) 117 - 126 1881-6118 2011/02 [Refereed][Not invited]
  • 児玉 淳一, 中谷 匡志, 奈良 禎太, 後藤 龍彦, 藤井 義明, 金子 勝比古
    J. MMIJ 127 (3) 117 - 126 1881-6118 2011 [Refereed][Not invited]
  • A. Mufundirwa, Y. Fujii, J. Kodama
    INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES 47 (7) 1079 - 1090 1365-1609 2010/10 [Refereed][Not invited]
     
    Predicting the failure-time of geo-hazards is an important rock mechanics problem. We first evaluated the validity of the INVerse-velocity (INV) method to predict failure-time of rock mass and landslides. This method utilizes rates of displacement or strain to predict the actual failure-time (T(f)), so the value of total displacement or strain before "failure" is not crucial. Second, we developed a new method for computing failure-time predictions based on the SLOpe (gradient) to predict Tf, termed the SLO method. Finally, a simple conceptualised model representing "safe" and "unsafe" predictions was proposed. To validate these hypotheses, prediction of rock mass failure in the Asamushi and Vaiont landslides (in situ studies) was conducted. Furthermore, laboratory conditions were incorporated into the research, which include predictions using circumferentials train and axial strain from uniaxial compression creep test on Shikotsu welded tuff (SWT), and predictions of failure-time for Inada granite under Brazilian creep tests. It was found that the SLO method is better than the INV method; SLO gave safe predictions in all the cases. In contrast, INV tends to give unsafe predictions(predicted failure-time Tfp > Tf). Our findings reveal that predictions using circumferential strain are better than those made using axial strain for SWT, and notably, given failure with very short tertiary creep, the methods tend to show limited reliability. However, the SLO method could find extensive application in predicting failure-timeofgeo-hazards, for instance, roof wall failure in mines, etc. (c) 2010 Elsevier Ltd. All rights reserved.
  • 高田 迪彦, 藤井 義明
    J. MMIJ 126 (3) 72 - 77 1881-6118 2010 [Refereed][Not invited]
  • A. Mufundirwa, Y. Fujii
    ROCK MECHANICS IN CIVIL AND ENVIRONMENTAL ENGINEERING 567 - 570 2010 [Refereed][Not invited]
     
    Can we predict failure-time of geo-hazards? Prediction of geo-hazards, for instance, rock mass failure, landslides, etc., is still a challenge to date in the rock mechanics field. Geo-hazards still pose a major threat to life and major loss in terms of economics. The focal point of our research is to predict failure-time of geo-hazards. Firstly, the authors evaluated the validity of the Inverse-velocity (INV) method to predict failure-time of rock mass and landslides. Secondly, two methods for computing predictions were also evaluated: (I) based on non-linear approximation (NLA), and (2) on the slope (gradient) to compute T(f),, termed the SLO method, which will be described in detail in the paper. The concept of "safe" and "unsafe" predictions was developed to classify predictions. With this in mind, prediction of failure case histories and rock specimens in the laboratory is presented. It was realised that SLO is better than the INV method.
  • 真田 祐幸, 丹生屋 純夫, 松井 裕哉, 藤井 義明
    J. MMIJ 125 (10/11) 530 - 539 1881-6118 2009 [Refereed][Not invited]
  • 真田 祐幸, 丹生屋 純夫, 松井 裕哉, 藤井 義明
    J. MMIJ 125 (10/11) 521 - 529 1881-6118 2009 [Refereed][Not invited]
  • 児玉 淳一, 後藤 龍彦, 藤井 義明
    J. MMIJ 125 (9) 472 - 480 1881-6118 2009 [Refereed][Not invited]
  • 藤井 義明, 大高 憲道, 中川 嘉文, 児玉 淳一
    J. MMIJ 124 (2) 120 - 128 1881-6118 2008 [Refereed][Not invited]
  • 石島 洋二, 藤井 義明, 市原 義久, 児玉 淳一
    J. MMIJ 124 (6/7) 435 - 444 1881-6118 2008 [Refereed][Not invited]
  • 石島 洋二, 藤井 義明, 市原 義久, 木山 保, 高田 迪彦, 菅原 隆之, 熊倉 聡
    J. MMIJ 124 (6/7) 445 - 451 1881-6118 2008 [Refereed][Not invited]
  • 児玉 淳一, 後藤 龍彦, 藤井 義明
    Journal of MMIJ 124 (12) 733 - 740 1881-6118 2008 [Refereed][Not invited]
  • 李 基夏, 石島 洋二, 菅原 隆之, 藤井 義明
    Journal of MMIJ 123 (6/7) 336 - 341 1881-6118 2007 [Refereed][Not invited]
  • 小玉齊明, 藤井義明, 赤川敏, 石島洋二
    土木学会論文集 63 (1) 24 - 33 1880-604X 2007 [Refereed][Not invited]
  • 藤井 義明, 大高 憲道, 中川 嘉文, 児玉 淳一
    資源と素材 122 (10/11) 483 - 488 0916-1740 2006 [Refereed][Not invited]
  • 藤井 義明, 上原 洋次郎
    資源と素材 122 (6/7) 330 - 337 0916-1740 2006 [Refereed][Not invited]
  • A Modeling Method on Fractal Distribution of Cracks in Rocks using AE Monitoring
    J. Acoustic Emission 23 119 - 128 2005 [Refereed][Not invited]
  • Y Fujii, Y Ishijima
    INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES 41 (6) 1035 - 1041 1365-1609 2004/09 [Refereed][Not invited]
  • 『土木学会論文集』 778 (III-69) 195 - 204 2004 [Refereed][Not invited]
  • 小玉斉明, 藤井義明, 藤田泰之, 石島洋二
    資源と素材 119 (8) 461 - 468 0916-1740 2003 [Refereed][Not invited]
  • 藤井 義明, 堀場 夏峰, 石島 洋二
    『資源と素材』 118 (3/4) 157 - 164 0916-1740 2002 [Refereed][Not invited]
  • 藤井 義明, 宮下 尚志, 石島 洋二, 川北 稔
    『地盤工学会論文報告集』 42 (3) 129 - 136 1341-7452 2002 [Refereed][Not invited]
  • 藤田泰之, 藤井義明, 石島洋二
    『資源と素材』 116 (7) 565 - 571 0916-1740 2000 [Refereed][Not invited]
  • 「非造構性の節理に起因する岩盤崩壊の機構-北海道積丹半島セタカムイ崩壊-」
    『地形』 Vol. 21 (No. 2) 169 - 191 2000 [Refereed][Not invited]
  • Y Fujii, T Kiyama, Y Ishijima, J Kodama
    INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES 36 (3) 323 - 337 0148-9062 1999/04 [Refereed][Not invited]
     
    Creep tests were carried out on Inada granite under confining pressure and on dry and wet specimens of Kamisunagawa sandstone. Distinctive points Q(A) (the point where the axial strain rate reaches a minimum), Q(C) (the point where the magnitude of circumferential strain rate reaches a minimum) and R-C (the point where the magnitude of circumferential strain acceleration begins to increase) were defined. Dependency of the strain values at the distinctive points on creep stress, confining pressure and water presence was examined. Circumferential strain at Q(C) or P-C was not affected by creep stress for both rocks. Peak load points were observed in reloading stress-strain curves when reloading was carried out before Q(C) for Kamisunagawa sandstone. Circumferential strain values at peak load during reloading coincided with critical extensile strain, which is defined as circumferential strain value at peak load during constant strain rate tests and is insensitive to confining pressure, water presence, and anisotropy, although slightly affected by strain rate. Load increased slightly or did not increase when reloading was carried out after R-C for both rocks. R-C in creep tests scattered around unloading stress-strain curves from peak load during constant strain rate tests for Kamisunagawa sandstone. These observations suggest that Q(C) and P-C in creep tests are closely related to the peak load points during constant strain rate tests. Circumferential strain would be used as a condition-insensitive damage indicator of rock in creep tests as well as in constant strain rate tests. (C) 1999 Elsevier Science Ltd. All rights reserved.
  • Y. Fujii, T. Kiyama, Y. Ishijima, J. Kodama
    International Journal of Rock Mechanics and Mining Sciences 36 (3) 323 - 337 1365-1609 1999 [Refereed][Not invited]
     
    Creep tests were carried out on Inada granite under confining pressure and on dry and wet specimens of Kamisunagawa sandstone. Distinctive points QA (the point where the axial strain rate reaches a minimum), QC (the point where the magnitude of circumferential strain rate reaches a minimum) and RC (the point where the magnitude of circumferential strain acceleration begins to increase) were defined. Dependency of the strain values at the distinctive points on creep stress, confining pressure and water presence was examined. Circumferential strain at QC or RC was not affected by creep stress for both rocks. Peak load points were observed in reloading stress-strain curves when reloading was carried out before QC for Kamisunagawa sandstone. Circumferential strain values at peak load during reloading coincided with critical extensile strain, which is defined as circumferential strain value at peak load during constant strain rate tests and is insensitive to confining pressure, water presence, and anisotropy, although slightly affected by strain rate. Load increased slightly or did not increase when reloading was carried out after RC for both rocks. RC in creep tests scattered around unloading stress-strain curves from peak load during constant strain rate tests for Kamisunagawa sandstone. These observations suggest that QC and RC in creep tests are closely related to the peak load points during constant strain rate tests. Circumferential strain would be used as a condition-insensitive damage indicator of rock in creep tests as well as in constant strain rate tests.
  • Y Fujii, T Kiyama, Y Ishijima, J Kodama
    PURE AND APPLIED GEOPHYSICS 152 (3) 551 - 577 0033-4553 1998/10 [Refereed][Not invited]
     
    Uniaxial compression, triaxial compression and Brazialian tests were conducted on several kinds of rock, with particular attention directed to the principal tensile strain. In this paper we aim to clarify the effects of the experimental environment-such as confining pressure, loading rate, water content and anisotropy-on the critical tensile strain, i.e., the measured principal tensile strain at peak load. It was determined that the chain-type extensometer is a most suitable method for measuring the critical tensile strain in uniaxial compression tests. It is also shown that the paper-based strain gage, whose effective length is less than or equal to a tenth of the specimen's diameter and glued on with a rubber-type adhesive, can be effectively used in the Brazilian tests. The effect of confining pressure P-C on the critical tensile strain epsilon(TC) in the brittle failure region was between -0.02 x 10(-10) Pa-1 and 0.77 x 10(-10) Pa-1. This pressure sensitivity is small compared to the critical tensile strain values of around -0.5 x 10(-2). The strain rate sensitivities partial derivative epsilon(TC)/partial derivative{log(d\epsilon\/dt)} were observed in the same way as the strength constants in other failure criteria. They were found to be from -0.10 x 10(-3) to -0.52 x 10-3 per order of magnitude in strain rate in the triaxial tests. The average magnitude of the critical tensile strain epsilon(TC) increased due to the presence of water by 4% to 20% for some rocks, and decreased by 22% for sandstone. It can at least be said that the critical tensile strain is less sensitive to water content than the uniaxial compressive strength under the experimental conditions reported here. An obvious anisotropy was observed in the P-wave velocity and in the uniaxial compressive strength of Pombetsu sandstone. It was not observed, however, in the critical tensile strain, although the data do show some variation. A "tensiie strain criterion" was proposed, based on the above experimental results. This criterion signifies that stress begins to drop when the principal tensile strain reaches the critical tensile strain. The criterion is limited to use within the brittle failure region. The critical tensile strain contains an inelastic strain component as well as an elastic one. It is affected by the strain rate, however, it is relatively insensitive to the confining pressure, the presence of water and anisotropy.
  • 藤井 義明, 石島 洋二
    『資源と素材』 114 (3) 169 - 174 0916-1740 1998 [Refereed][Not invited]
  • 藤井義明, 石島洋二, 堀場夏峰, 稲葉力
    『資源と素材』 114 (12) 869 - 874 0916-1740 1998 [Refereed][Not invited]
  • Y Fujii, Y Ishijima, G Deguchi
    INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES 34 (1) 85 - 96 0148-9062 1997/01 [Refereed][Not invited]
     
    A new method is proposed for predicting rockbursts, as well as microseismicity in deep longwall coal mining. The method is able to predict failure in the coal seam and in the rock mass by using 3-D elastic numerical stress analyses. These locations were compared with the results of microseismic monitoring. Fracturing intensity and its variation with respect to face advance were represented by the maximum shear seismic moment release rate. The ''Seismic Moment Method'' was applied to three cases in the Horonai Coal Mine and in the Miike Coal Mine, Japan. The first case considered panels W8-5U and W8-5 in the Horonai Coal Mine at 1055 and 1125 m deep. Even though no rockburst occurred, areas where microseismic events were concentrated were predicted. It was also clear, by comparing calculated maximum shear seismic moment release rate to observed data, that the magnitude of the seismicity and its variation with respect to the face advance were also successfully predicted. The second case corresponded to panel W6-3 in the same mine from 915 to 985 m deep. Microseismic monitoring had not yet been introduced; however, the rockburst in this panel was successfully predicted as fracturing of coal seam elements al the coalface. The last case considered panels E3-E6 in the Miike Coal Mine at 600 and 650 m deep, respectively. The location and intensity of microseismicity were again predicted; in addition, toppling as well as rockbursts were also predicted. Relations between the extent of the relief zone ahead of the coal face and the occurrence of rockbursts are discussed. An effective method to prevent rockburst hazard is also proposed. (C) 1997 Elsevier Science Ltd.
  • 藤井義明, 木山保, 大森瑞穂, 石島洋二
    『資源と素材』 113 (3) 162 - 168 0916-1740 1997 [Refereed][Not invited]
  • 後藤 龍彦, 児玉 淳一, 吉田 豊, 板倉 賢一, 藤井 義明
    『資源と素材』 112 (7) 439 - 444 0916-1740 1996 [Refereed][Not invited]
  • FUJII Yoshiaki, ISHIJIMA Yoji
    Journal of the Mining and Materials Processing Institute of Japan 資源・素材学会 111 (9) 601 - 606 0916-1740 1995/08 [Refereed][Not invited]
  • GOTO Tatsuhiko, MATSUMOTO Hiroyuki, FUJII Yoshiaki, KODAMA Jun-ichi, SATO Tateki, DEGUCHI Gouta
    Journal of the Mining and Materials Processing Institute of Japan 資源・素材学会 111 (4) 213 - 218 0916-1740 1995/04 [Refereed][Not invited]
  • FUJII Yoshiaki, ISHIJIMA Yoji, DEGUCHI Gota
    Journal of the Mining and Materials Processing Institute of Japan 資源・素材学会 111 (1) 10 - 16 0916-1740 1995/01 [Refereed][Not invited]
  • 藤井 義明, 石島 洋二, 後藤 龍彦
    資源と素材 111 (14) 993 - 1000 0916-1740 1995 [Refereed][Not invited]
  • 藤井 義明, 石島 洋二
    資源と素材 資源・素材学会 110 (12) 992 - 998 0916-1740 1994/10 [Refereed][Not invited]
  • 藤井 義明, 石島 洋二
    資源と素材 資源・素材学会 110 (7) 527 - 532 0916-1740 1994/06 [Refereed][Not invited]
  • 藤井 義明, 木山 保, 石島 洋二
    資源と素材 資源・素材学会 110 (3) 211 - 214 0916-1740 1994/03 [Refereed][Not invited]
  • 藤井 義明, 福島 猛, 石島 洋二
    資源と素材 資源・素材学会 110 (3) 233 - 239 0916-1740 1994/03 [Refereed][Not invited]
  • 藤井 義明, 後藤 竜彦, 佐藤 干城
    資源と素材 資源・素材学会 109 (1) p37 - 42 0916-1740 1993/01 [Refereed][Not invited]
  • Y FUJII, Y ISHIJIMA, T GOTO
    11TH INTERNATIONAL CONFERENCE ON GROUND CONTROL IN MINING - PROCEEDINGS 414 - 420 1992 [Refereed][Not invited]
  • 藤井 義明, 石島 洋二
    資源と素材 資源・素材学会 107 (5) 253 - 258 0916-1740 1991/04 [Refereed][Not invited]
  • Yoshiaki Fujii, Yoji Ishijima
    Mining Science and Technology 12 (3) 265 - 285 0167-9031 1991 [Refereed][Not invited]
     
    To find an effective numerical simulation method for microseismicity induced by deep mining activity, results obtained by using four simulation methods, namely: (1) the energy release rate method, based on Cook's study (2) the strain energy release rate method, developed by the authors (3) the volume excess shear stress index method, based on Spottiswoode's study and (4) the maximum shear seismic moment release rate method, developed here by the authors were compared with the microseismicity in a Japanese deep longwall coal mine. The maximum shear seismic moment release rate method was discovered to be the best method, since the intensity of microseismicity in a longwall coal panel, its variation with the face advance and the distribution of microseismic events were well simulated. © 1991 Elsevier Science Publishers B.V.
  • 藤井 義明, 石島 洋二
    日本鉱業会誌 資源・素材学会 104 (1204) p345 - 351 0369-4194 1988/06 [Refereed][Not invited]
  • 石島 洋二, 藤井 義明
    日本鉱業会誌 資源・素材学会 103 (1198) p835 - 840 0369-4194 1987/12 [Refereed][Not invited]

Books etc

  • 斜面崩壊対策技術
    石川芳治, 藤井義明ら (Joint work第1編第3章「岩盤斜面の崩壊メカニズム」)
    エヌ・ティー・エス 2014
  • トンネルの変状メカニズム
    (社)土木学会 2003
  • 露天掘鉱山における残壁技術解説書
    (社)資源・素材学会 2003
  • 岩盤崩壊の発生機構と計測技術
    社団法人地盤工学会北海道支部 2000
  • Advances in Rock Mechanics
    World Scientific Publishing 1998

Conference Activities & Talks

  • Investigation of Rockburst in Deep Underground Mines, A case study of Mufulira mine, Copperbelt, Zambia  [Not invited]
    Sinkala, P, Nishihara, M, Fujii, Y, Fukuda, D, Kodama, J
    Annual Meeting of ARMA (American Rock Mechanics Association)  2019/06
  • Effects of transient axial stress or pore pressure disturbances on the permeability of Shikotsu welded tuff  [Not invited]
    Boeut S, Fujii Y, Kodama J, Fukuda D, Dassanayake. A.B.N
    Annual Meeting of ARMA (American Rock Mechanics Association)  2019/06
  • Influence of transient stress disturbances on permeability of Kushiro Cretaceous sandstone  [Not invited]
    Boeut, S, Oshima, T, Fujii, Y, Kodama, J.-I, Fukuda, D, Matsumoto, H, Uchida, K
    ARMS10 (10th Asian Rock Mehcnaics Symposium, The ISRM International Symposium for 2018)  2018/11
  • Development of 2-D hybrid FEM/DEM method code using GPGPU  [Not invited]
    Fukuda, D, Mohammadnejad, M, Chan, A, Cho, S. H, Min, G. J, Kodama, J, Fujii, Y
    ARMS10 (10th Asian Rock Mehcnaics Symposium, The ISRM International Symposium for 2018)  2018/10
  • Study of factors behind rock slope displacement at Higashi Shikagoe limestone quarry  [Not invited]
    Bandazi, C. N, Uy, R, Kodama, J, Fujii, Y, Fukuda, D, Iwasaki, H, Ikegami, S
    European Rock mechanics Symposium(EUROCK2018)  2017/11
  • Effect of Axial Stress Disturbances on Permeability of Kushiro Sandy Shale  [Not invited]
    Boeut, S, Oshima, T, Fujii, Y, Kodama, J, Fukuda, D, Matsumoto, H, Uchida, K
    1st. International KAMPAI Symposium on Sustainable Management of Resources and Environment in the 21st. Century  2017/11
  • Water Vapour Diffusion in Sandstone during Rainy Season in Mchenga Underground Coal Mine, Malawi  [Not invited]
    Yasidu, U, Fujii, Y, Kodama, J, Fukuda, D, Dandadzi, J, Maneya, G
    1st. International KAMPAI Symposium on Sustainable Management of Resources and Environment in the 21st. Century  2017/11
  • Geological Disposal of High-level Radioactive Waste in Japan and the Role of Rock Engineering  [Invited]
    Fujii, Y
    International Symposium on Earth Resources Management & Environmnet  2017/08
  • Prevention of Catastrophic Volcanic Eruptions  [Not invited]
    Fujii, Y, Kodama, J, Fukuda, D, Dassanayake, A.B.N
    International Symposium on Earth Resources Management & Environmnet  2017/08
  • Effect of Humidity on Tensile Strength of Rocks in Selected Underground Coal Mines in Malawi  [Not invited]
    Yasidu, U.M, Fujii, Y, Fukuda, D, Kodama, J, Maneya, G
    51st U.S. Rock Mechanics Geomechanics Symposium  2017/06
  • Change in Permeability of Cretaceous Sandy Shale in Kushiro Coal Mine due to Axial Stress Disturbance  [Not invited]
    Boeut, S, Oshima, T, Fujii, Y, Kodama, J, Fukuda, D, Matsumoto, H, Uchida, K
    2017 International Joint Symposium between CERI (Japan) and IEGS (Korea)  2017/06
  • Effects of Confining Pressure on Strain Rate-Dependent Deformation and Failure of Kimachi Sandstone  [Not invited]
    Amo, K, Fujii, Y, Kodama J, Fukuda, D
    ARMS9  2016/10
  • 3-D Analysis of Time-dependent Behavior of Tunnel Crossing Weak Rock Formation  [Not invited]
    Kodama, J, Tabata, S, Fukuda, D, Fujii, Y, Murayama, H, Niwa, H, Sainoki, A
    ARMS9  2016/10
  • Kimachi Sandstone does not have to Fail under Larger Stress  [Not invited]
    Wang, Y, Fujii, Y, Fukuda, D, Kodama, J
    EUROCK 2016  2016/08
  • Effect of Butress on Reduction of Rock Slope Sliding along Geologic Boundary  [Not invited]
    Moriya, R, Fukuda, D, Kodama, J, Fujii, Y
    3rd. International Symposium on Mine Safety, Science and Engineering  2016/08
  • New Techniques for Monitoring and Analyzing the Stability of Steep Cliffs against Rock Falls  [Not invited]
    Fujii, Y, Maeda, S, Sugawara, T, Kodama, N, Miyashita, N
    US Rock Mechanics/Geomechanics Symposium  2016/06
  • What Should We Do to Improve the Future for Humans?  [Invited]
    Fujii, Y
    ASEAN++,  2016
  • Time-dependent Mechanical Behaviors of Frozen Welded Tuff  [Not invited]
    Kodama, J, Mitsui, Y, Sugawara, T. Fukuda, D, Fujii, Y
    ISRM Congress 2015  2015/10
  • Giant Earthquakes are Occurring at Lunar Phases Specific to Each Subduction Zone  [Not invited]
    Fujii, Y, Kodama, J, Fukuda, D
    ISRM Congress 2015  2015/10
  • Evaluation of 3-D Strain Distribution in Lignite Based on Image Analysis  [Not invited]
    Fukuda, D, Maruyama, M, Kodama, J, Fujii,Y, Aramaki, N, Kaneko, K, Nara, Y
    ISRM Congress 2015  2015/10
  • The Cause of Global Warming Stagnation in the 21st Century  [Not invited]
    Fujii, Y
    The 8th International Conference on Earth Resources Technology  2014/10
  • Prediction of Time and Volume of Rock Failure by Slope Method  [Not invited]
    Fujii, Y, Mufundirwa, A, Kodama, J, Fukuda, D
    The 3rd. International Conference on Advances in Mining and Tunneling  2014/10
  • Sealability Recovery of Fractured Rocks by Post-failure Consolidation  [Not invited]
    Fujii, Y, Kumakura, S, Kaneko, K
    ARMS8  2014/10
  • Creep Behavior of Frozen Shikotsu Welded Tuff  [Not invited]
    Mitsui, Y, Hara, S, Akabane, K, Kodama, J, Sugawara, T, Fukuda, D, Fujii, Y
    ARMS8  2014/10
  • Significant Differences in Effective Stress Coefficient for Rocks within Elastic Region and Peak and Residual Strengths  [Not invited]
    FUJII Yoshiaki
    Dassanayake, A. B. N., Fujii, Y., Fukuda, D. and Kodama, J.  2014/10
  • Uniaxial Compressive Strength of Shikotsu Welded Tuff and Bibai Sandstone at Sub-zero Temperature  [Not invited]
    Hara, S, Kodama, J, Fujii, Y, Fukuda, D, Mitsui, Y, Sugiura, T
    ARMS8  2014/10
  • Investigation of Rock Slope Deformation Modes due to Excavation on Mountain Type Mine  [Not invited]
    Najib, Fukuda, D, Kodama, J, Fujii, Y
    ARMS8  2014/10
  • Numerical Study on Fracturing Process in Rock by Blasting a Cylindrical Charge  [Not invited]
    Fukuda, D, Ikezawa, J, Kaneko, K, Kodama, J, Fujii, Y
    ARMS8  2014/10
  • Shale Gas Extraction and CCS May Induce Serious Seismicity  [Not invited]
    Fujii, Y, Takahashi, K, Fukuda, D, Kodama, J
    Workshop on Rock Engineering and Environment  2014/10
  • Consideration on the Tunnel Supporting Effectiveness of Shotcrete with a Time-dependent Viscoelastic Model,  [Not invited]
    Tani, T, Aoki, T, Ogawa, T, Fujii, Y
    Computer Methods and Recent Advances in Geomechanics  2014/09
  • Temperature-Confining Pressure Coupling Effects on the Permeability of Three Rock types under Triaxial Compression  [Not invited]
    Alam, A. K. M. B, Fujii, Y, Fukuda, D, Niioka, M
    EUROCK 2014  2014/05
  • Biot’s Effective Stress Coefficient of Rocks for Peak and Residual Strengths by Modified Failure Envelope Method  [Not invited]
    Dassanayake, A. B. N, Fujii, Y
    EUROCK 2014  2014/05
  • Why Do Giant Earthquakes Occur at Lunar Phases Specific to Each Subduction Zone?  [Not invited]
    Fujii, Y, Ozaki, Y, Fukuda, D, Kodama, J
    6th Int. Symp. on In-situ Rock Stres  2013/08
  • Effect of Confining Pressure on Permeability during Deformation and Failure of Several Rocks under Compression  [Not invited]
    Alam A.K.M. B, Niioka M, Fujii Y
    47th US Rock Mechanics/ Geomechanics Symosium in San Fransisco  2013/06
  • Mechanisms of Falling Rock Formation at Steep Slope due to Temperature Perturbation  [Not invited]
    Keppetipola, S.S.S.S.M, Fujii Y, Kodama, N
    47th US Rock Mechanics/ Geomechanics Symosium in San Fransisco  2013/06
  • An Analytical Study on the Effect of Weak Layer on the Long-term Behavior of Tunnels  [Not invited]
    Kodama, J, Mitsui, Y, Fukuda, D, Fujii, Y, Hagan, P
    5th AUN/SEED/Net Regional Conference on Geological Engineering  2013/01
  • Effect of Temperature and Confining Pressure on Permeability during Deformation and Failure of Shikotsu Welded Tuff  [Not invited]
    Alam, B. A.K.M, Niioka, M, Fujii, Y. Kodama, J, Sugawara, T
    ARMS7  2012/10
  • Date, Lunar Phase and Time of Giant Earthquakes might be Specified for Each Subduction Zone  [Not invited]
    Fujii, Y, Ozaki, Y
    Seismological Society of America 2012 Annual Meeting  2012/04
  • Giant Eruptions did not Frequently Occur in the Periods When Giant Earthquakes Frequently Occurred and vice versa after 1900  [Not invited]
    Fujii, Y
    Seismological Society of America 2012 Annual Meeting  2012/04
  • 自然はやんちゃ  [Not invited]
    藤井 義明
    平成23年度北海道資源・素材フォーラム「北海道の地震・津波・噴火」  2011/12
  • Abandoned roadways aged up to 50 years observed in Kushiro Coal Mine, Japan  [Not invited]
    Fujii, Y, Sugawara, T, Kodama, J, Ishijima, Y, Kiyama, T, Takada, M, Ishihara, Y, Kumakura, S, Narita, T, Sawada, M, Nakata, E
    12th. Int Congr. Rock Mech.  2011/10
  • Analysis of Natural Rock Slope Deformations under Temperature Variation: A Case Study from Japan  [Not invited]
    Mufundirwa A, Fujii, Y, Kodama, N, Kodama, J
    Slope Stability  2011/09
  • Foreshocks had been Observed since Two Days before the 2011 off the Pacific Coast of Tohoku Earthquake!  [Not invited]
    Fujii, Y
    Society of America, 2011 Annual Meeting  2011/04
  • Influence of Stress Larger than Preload but Acted for Shorter Duration in Tangent Modulus Method - A New Method to Measure In-situ Rock Stress  [Not invited]
    Fujii, Y, Kondo, K
    ISRM International Symposium 2010 and 6th Asian Rock Mechanics Symposium  2010/10
  • Prediction of Rock Mass Failure-time of Geo-hazards  [Not invited]
    Mufundirwa A, Fujii, Y, Kodama, J
    EUROCK 2010  2010/06
  • Influence of Atmospheric Nuclear Explosions on Climate Change  [Not invited]
    Fujii, Y
    90th AMS Annual Meeting  2010/01
  • 今後100年くらいの間、人類が今と同じ程度の文化的生活を継続するために日本は何をすべきか  [Not invited]
    藤井 義明
    資源・素材2009(札幌)  2009/09
  • Development of Rock Stress Measurement Probe Based on The Pilot Hole Wall Deformation Method Laboratory Tests  [Not invited]
    Lee, K, Ishijima, Y, Fujii, Y, Koo, H
    43rd. U.S. and 4th U.S. Canada Rock Mechanics Symposium  2009/07
  • Mechanical Properties of Siliceous Rocks around the Horonobe URL from Triaxial Compression and Isotropic Consolidation Tests  [Not invited]
    Sanada, H, Matsui, H, Fujii, Y
    ISRM-Sponsored Int. Symp. Rock Mech  2009/05
  • Things Hidden by the Global Warming  [Not invited]
    Fujii, Y, Abe, H
    3rd Int. Workshop and Conference on Earth Resources Technology  2009/05
  • New Methods for Prediction of Geomechanical Failure-time  [Not invited]
    Mufundirwa, A, Fujii, Y
    Korean Rock Mechanics Symposium 2008  2008/10
  • Effects of strain rate and temperature on Tangent Modulus Method  [Not invited]
    Makasi M, Fujii Y
    Korean Rock Mechanics Symposium 2008  2008/10
  • Increase in Sealability of Fractured Sedimentary Rock with Time  [Not invited]
    Fujii, Y
    Int. Symp. Sealability of Geomaterials  2005/07
  • A Modeling Method on Fractal Distribution of Cracks in Rocks Using AE Monitoring  [Not invited]
    Watanabe, Y, Itakura, K, Sato, K, Fujii, Y, Balusu, R, Guo, H, Luo, X
    17th International Acoustic Emission Symposium  2004/11
  • The Effect of Temperature on the Mechanical Properties of Inada Granite and Shirahama Sandstone  [Not invited]
    Kodama, N, Fujii, Y, Ishijima, Y
    The 1st Kyoto International Symposium on Underground Environment  2003/03
  • Numerical Simulation on Microseismicity due to Mining at One of the Collieries in Australia  [Not invited]
    Fujii, Y, Balusu, R, Deguchi, G, Ishijima, Y
    20th Int. Conference on Ground Control in Mining  2001/08
  • A Study on the Mechanism of Slope Failure at Toyohama Tunnel  [Not invited]
    Ishijima, Y, Fujii, Y
    NY Rocks '97  1997/07
  • 'Condition Insensitive Damage Indicator' for Brittle Rock  [Not invited]
    Fujii, Y, Ishijima, Y
    NY Rocks '97  1997/07
  • 引張ひずみ規準について  [Invited]
    藤井 義明
    大深度地下空間開発技術研究講演会  1994/10
  • A New Criterion for Brittle Failure of Rock  [Not invited]
    Fujii,Y, Kiyama,T, Ishijima,Y
    MMIJ/AusIMM Joint Symp.  1994/10
  • Application of DDM to Some Rock Pressure Problems in Japanese Deep Coal Mines  [Not invited]
    Fujii, Y, Ishijima, Y, Goto
    11 th. Intl. Conf. on Ground Control in Mining  1992/07
  • Numerical Analysis of Maximum Shear Seismic Moment Release for Microseismicity Induced by Deep Coal Mining  [Not invited]
    Fujii,Y, Ishijima,Y
    10 th. Int. Acoustic Emission Symp.  1990/10
  • Criterion for Occurrence and Focal Mechanism of Seismic Events Around Underground Excavation  [Not invited]
    Sato,K, Fujii,Y
    2nd. Intl. Symp. of Rockbursts and Seismicity in Mines  1990/06
  • Microseismicity Induced by Deep Coal Mining Activity  [Not invited]
    Ishijima, Y, Fujii, Y, Sato, K
    6th. ISRM Congress  1987/08
  • Microseismic Activity Induced by Longwall Coal Mining  [Not invited]
    Sato, K, Fujii, Y, Ishijima, Y, Kinoshita, S
    4 th. Conf. on Acoustic Emission / Microseismic Activity in Geologic Structures and Materials  1985/10

Works

  • fftimer
    2008
  • ev
    1998

MISC

Awards & Honors

  • 2019/12 YSRM2019 & REIF2019, The 5th ISRM Young Scholars' Symposium on Rock Mechanics and International Symposium on Rock Engineering for Innovative Future Excellent Paper Award
     
    受賞者: Fukuda, D;Mohammadneja, M;Liu, H;Han, H;Kodama, J.-I;Fujii, Y
  • 2017/05 日本材料学会 優秀講演発表賞
     Smeared Crack Model及び有限要素法を用いた岩石の動的亀裂進展解析に関する基礎的研究 
    受賞者: 福田大祐;二瓶恵理菜;児玉淳一;藤井義明;Sang-Ho CHO;Se-Wook OH
  • 2017/01 第14回岩の力学国内シンポジウム 最優秀ポスター賞
     3次元動的破壊プロセス解析法を用いた岩石の動的引張試験に関する基礎的検討 
    受賞者: 二瓶恵理菜;福田大祐;Sang-Ho CHO;Se-Wook OH;児玉淳一;藤井義明
  • 2015/12 Elsevier Recognized Reviewer
     
    受賞者: FUJII Yoshiaki
  • 2014/11 Int. J. Rock Mech. Min. Sci. Outstanding Contribution in Reviewing
     
    受賞者: FUJII Yoshiaki
  • 2014/05 EUROCK 2014 Outstanding Paper Award for Young Scientists and Engineers
     Temperature-Confining Pressure Coupling Effects on the Permeability of Three Rock types under Triaxial Compression 
    受賞者: Alam, A. K. M. B;Fujii, Y;Fukuda, D;Niioka, M
  • 2010/06 日本応用地質学会北海道支部・北海道応用地質研究会合同研究発表会 優秀発表者賞
     珪質泥岩を対象にした孔壁変形法による初期地圧測定-幌延深地層研究センター,深度250m連絡坑道での測定事例- 
    受賞者: 熊倉聡;杉田裕;真田祐幸;中村隆浩;小原勇一;菅原隆之;藤井義明
  • 2010/06 EUROCK 2010 Best Paper Award for Young Scientists and Engineer
     Prediction of Rock Mass Failure-time of Geo-hazards 
    受賞者: Mufundirwa A;Fujii, Y;Kodama, J
  • 2006/01 第35回岩盤力学に関するシンポジウム 優秀講演論文賞
     数種の岩石の凍結融解および凍上に伴う変形挙動 
    受賞者: 小玉齊明;赤川敏;藤井義明;石島洋二
  • 2002/05 地盤工学会 事業企画推進賞
     
    受賞者: 岩盤崩落の機構解明と計測技術に関する研究委員会
  • 1999/06 資源・素材学会北海道支部 支部長賞佳作
     岩盤力学の新たなる展開、-軸差応力・軸差ひずみ・せん断破壊・摩擦角からの脱却- 
    受賞者: 藤井 義明
  • 1997/03 資源・素材学会 奨励賞
     深部炭鉱における地圧現象に関する一連の研究 
    受賞者: 藤井 義明

Research Grants & Projects

  • Deformation and Failure of Rock and Rock Mass
    Grant-in-Aid for Scientific Research
    Date (from‐to) : 1984

Educational Activities

Teaching Experience

  • Resources Sustainability
    開講年度 : 2018
    課程区分 : 修士課程
    開講学部 : 工学院
  • Resources Sustainability
    開講年度 : 2018
    課程区分 : 修士課程
    開講学部 : 工学院
  • Resources Sustainability
    開講年度 : 2018
    課程区分 : 修士課程
    開講学部 : 工学院
    キーワード : 資源、環境、地球、温暖化、人口増加、資源枯渇、食糧危機
  • Resources Sustainability
    開講年度 : 2018
    課程区分 : 修士課程
    開講学部 : 工学院
    キーワード : 資源、環境、地球、温暖化、人口増加、資源枯渇、食糧危機
  • Resources Sustainability
    開講年度 : 2018
    課程区分 : 博士後期課程
    開講学部 : 工学院
  • Resources Sustainability
    開講年度 : 2018
    課程区分 : 博士後期課程
    開講学部 : 工学院
    キーワード : 資源、環境、地球、温暖化、人口増加、資源枯渇、食糧危機
  • Introduction to Mineral Resources Engineering
    開講年度 : 2018
    課程区分 : 学士課程
    開講学部 : 工学部
    キーワード : 地殻資源 鉱床 開発技術 環境問題 未利用資源 リサイクル
  • Freshman Seminar
    開講年度 : 2018
    課程区分 : 学士課程
    開講学部 : 全学教育
    キーワード : 資源、環境、地球、温暖化、人口増加、資源枯渇、食糧危機
  • Rock Engineering
    開講年度 : 2018
    課程区分 : 学士課程
    開講学部 : 工学部
    キーワード : 岩石、強度、クリープ、疲労、岩盤、岩盤応力、岩盤斜面、地下空洞
  • Arts and Science Courses in English 2
    開講年度 : 2018
    課程区分 : 学士課程
    開講学部 : 国際本部
  • Theory of Elasticity
    開講年度 : 2018
    課程区分 : 学士課程
    開講学部 : 工学部
    キーワード : 応力、ひずみ、強度、応力解析

Social Contribution

Social Contribution

Others

  • 2012/12 -2012/12 STVラジオときめきワイド、笹子トンネル事故に関連して北海道のトンネルについて電話インタビュー
  • 2012/11 -2012/11 AIR G'(FM北海道)、北海道宝島において北海道の石炭鉱業についてインタビュー
  • 2012/04 -2012/04 藤井義明(2012)、石炭エネルギー技術小特集「石炭等エネルギーの開発・利用」の発刊に寄せて、J. MMIJ, Vol. 128, Nos. 4/5, p. 178
  • 2010/04 -2010/04 Scientists explore if we're in 'age of great quakes', U-T San Diego, by Gary Robbins, Apr. 10, 2011
    Scientists explore if we're in 'age of great quakes', U-T San Diego, by Gary Robbins, Apr. 10, 2011
  • 2008/06 -2008/06 uhbスーパーニュース出演、北海道の石炭についてコメント
  • 2008 -2008 Fujii, Y. (2008), Environmental Buisiness... E:VISION, Spring, 2008, p. 2
  • 1997 -1997 Fujii, Y. (1997), Circumferential Strain of Brittle Rocks Under Compression, ROCKbits, Rock Mechanics Research Center, The University of Oklahoma, Vol.4, No.1, p.3, Nov. 1997.


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