掲載種別：研究論文（大学，研究機関等紀要）  

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掲載種別：研究論文（大学，研究機関等紀要）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC  

There have been attempts to improve the operational efficiency of construction projects and plan response countermeasures for estimated damage following disasters through the utilization of accumulated electronic data, which constructs a digital twin that can reproduce a physical space in cyberspace and feedback the cyberspace simulation results to physical space. However, the application of such simulations is limited, unless numerical models can be automatically constructed from the data. In this study, we develop a program that utilizes a data processing platform to read, transform, and integrate data to create mediated data with a common data structure. This mediated data can be used to construct analytical models for various numerical analyses. Using the program developed, a grid model of 3-D ground surface as the mediated data was constructed based on borehole data obtained through a ground survey. Each grid point has basic material parameters of soil, and these parameters are estimated from borehole data and other investigation reports. Each grid point has general geotechnical parameters and can be easily converted to a 3-D finite-element model. When the borehole data is added or changed, the analytical model can be updated with almost no cost, whereas it would be very costly to create the model manually.

DOI： 10.1109/TMECH.2021.3105062

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掲載種別：研究論文（学術雑誌）   出版者・発行元：International Journal of Geomate  

DOI： 10.21660/2021.86.j2270

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：GEOMATE INT SOC  

Recently, the occurrence of large earthquakes has become a concern in Japan, prompting the need for a numerical method that can accurately predict real phenomena, such as the elastoplastic soil-water coupled finite element method. Because the elastoplastic constitutive model requires many material parameters, various soil tests and specialized knowledge are needed to determine these material parameters. In this study, a new method was proposed to determine the material parameters from the limited ground information obtained by borehole inspections and the method was validated by comparing the numerical results with monitored seismic behavior. One-dimensional seismic analyses were conducted using the material parameters estimated from borehole data near the target sites. It was confirmed that the amplitude and predominant period obtained by numerical simulation were consistent with the monitored data. As a result, it was found that the dynamic numerical result was more consistent with the monitored data when the compression index was set to be larger than that in the static analysis.

DOI： 10.21660/2021.85.j2228

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：International Journal of Geomate  

The pagoda of Wat Krasai, built in the 17th century on the outskirts of the Ayutthaya district in the Kingdom of Thailand, tilts approximately 2 degrees to the north and may continue to tilt further. The cause of this tilt is thought to be the uneven settlement of the foundation ground, but no supporting evidence has been presented. Three cohesive soil layers that may cause uneven settlement have been confirmed in the foundation ground around the pagoda, but soil tests are inadequate, leading to uncertainty in proving the cause of inclination. Hence, the cause of inclination was investigated in this study by calculating the inclination that can occur within the realistic ranges of the soil properties through numerical analysis using the finite element method. A method of correcting plane strain analysis, which has a low computational cost, with a three-dimensional effect coefficient, was utilized to assess over 500 cases considering ground material uncertainties, and the probability distribution of the possible inclinations was calculated. This method is useful as it considers fluctuations in the ground material parameters to address land settlement, which is largely influenced by the three-dimensional effects. This approach will also be applicable to future predictions aimed at pagoda preservation.

DOI： 10.21660/2021.82.j2108

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：Construction Materials & Environment  

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掲載種別：研究論文（研究会，シンポジウム資料等）  

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掲載種別：研究論文（研究会，シンポジウム資料等）   出版者・発行元：日本原子力学会  

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掲載種別：研究論文（研究会，シンポジウム資料等）   出版者・発行元：九州橋梁・構造工学研究会  

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

DOI： 10.1016/j.sandf.2020.08.005

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：International Journal of Geomate  

DOI： 10.21660/2020.73.96594

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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

DOI： 10.1016/j.sandf.2020.02.007

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

Although the soil, water and air coupling theory has been deductively derived from the three-phase mixture theory, assumptions and interpretations inherent in soil mechanics are also conveniently introduced in this theory. Mechanical properties of unsaturated soils are phenomenologically integrated into the constitutive equation for a deformation problem, with effective stress expressed as a combination of partial stresses acting on each phase of the mixture. The governing equations of two seepage problems describing the movements of pore water and pore air are formulated by a priori introduction of Darcy's law. Consequently, the coupling theory consists of a deformation problem and two seepage problems, in which the soil-water retention characteristics play the role of a mediator connecting these problems. If the theoretical structure is clarified in this way, an extension of this theory is easily made. In this paper, the extension of the theory to each of four examples and their performance is demonstrated. The features of settlement caused by absorption of soil water due to vegetation; dissolution, advection and diffusion of substances in groundwater; desaturation and state change due to vaporisation of dissolved gas from pore water; and the liquefaction potential of unsaturated soil are presented.

DOI： 10.1680/jgere.18.00004

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Tech Reviews Ltd  

In the wide area of the eastern part of Tokyo, the ground level is less than mean sea level. This area is more vulnerable to disasters than other areas. If large flood damage such as storm surge should occur in this area, the disaster would be a long-term catastrophe. On the coast of Tokyo Bay, countermeasures have been taken by tide embankments and floodgates. However, considering the damage scale when it occurs, an analysis in this area is very important. In this area, ground settlement occurred and groundwater head dropped because groundwater excessively withdrew by the industrial purpose during the period of economic growth. Currently, the groundwater head recovers and the ground settlement has been subsided. However, due to the groundwater head fluctuation, pore water pressure distribution had been different from hydrostatic pressure distribution. Therefore, in the analysis in this area, it is necessary to consider past groundwater head fluctuation. In this research, the ground settlement and the distribution of pore water pressure are simulated from groundwater level fluctuation over the past 100 years. Then, we conducted the seismic analysis by input the distribution of effective stress calculating from the simulated ground water pressure. The sites analyzed in this research are Tokyo Sea Life Park at the mouth of Arakawa River.

DOI： 10.32732/jcec.2019.8.2.41

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Oxford University Press (OUP)  

DOI： 10.1093/gji/ggy499

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.32732/jcec.2019.8.1.13

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

DOI： 10.2208/jscejsp.75.31

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/nag.2787

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Japanese Geotechnical Society  

In view of the need to utilize ocean space and to develop seabed resources, the assessment of the stability of deep seabed soil has emerged as an important challenge in the field of geomechanics. To study seabed stability, the strength and stiffness of the natural ground must be ascertained. Accordingly, it is necessary either to conduct laboratory testing on soil specimens sampled from the seabed or to estimate the strength and stiffness by in-situ tests. While in the future it may be reasonable to conduct in-situ tests to estimate the stiffness and strength of seabed soil, it will still be necessary to compare the physical properties measured by in-situ testing with those measured by laboratory testing in advance of these determinations. In short, soil specimens must be sampled from the actual deep seabed, and laboratory mechanical tests must be conducted on the sampled soil specimens. However, soil sampled from the ocean bottom is subject to effects that differ from those exerted on soil sampled from the earth. More specifically, the non-negligible effects of disturbance are expected with soil sampled from the ocean bottom. The effects of disturbance occur during the sampling process due to the vaporization of dissolved gases, as these soil specimens are under relatively higher pressure and contain pore water with a high amount of dissolved gases. Therefore, numerical simulations were conducted in the present study to investigate the effects of vaporized dissolved gases on the mechanical behavior of soil specimens during sampling and on the undrained shear strength as determined by laboratory tests. The analyses revealed that the combination of the decreasing effective stress caused by the sampling and factors such as overconsolidation and unsaturation is attributable to the difference between the soil strength ascertained by laboratory testing and the in-situ soil strength.

DOI： 10.1016/j.sandf.2018.02.026

Scopus

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：GEOMATE International Society  

Currently, finite element codes for small-strain have been widely applied in geotechnical engineering problems. However, the limitations of these codes are recognized, especially when the strain is large. To overthrow such limitations, finite-strain finite element code for porous media is needed. Therefore, this study aims to implement the finite element code for coupled solid-fluid at finite strain for static and dynamic problems. Firstly, the governing equation for porous media at finite-strain was introduced. Then, the mixed formulation of both phases with respect to the reference coordinates by deriving the governing equations with respect to the reference or current coordinates and by considering the solid and fluid as separate, was given. At present, the code is developed only for elastic regime as its preliminary step. In this study, the proposed code has been verified with the static and dynamic problem. And, the result of the finite-strain finite element code is then compared with the result of the analytical solution and small-strain finite element code within the small-strain regime. Thereafter, the proposed code was used to estimate the response of the earthen dam when subjected to a dynamic load. Finally, the results, discussion, and comparison between small- and finite-strain finite element analyses were presented.

DOI： 10.21660/2018.51.86896

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.sandf.2017.08.001

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

Bentonite materials have been considered as a candidate material for engineered barriers in transuranium (TRU) waste disposal facilities due to their physical and chemical characteristics. Bentonite materials will be initially compacted and unsaturated. After closing the cavern, the bentonite material will become saturated through exposure to a percolating groundwater. It is therefore important to understand the behaviour of bentonite during saturation, which provides an initial condition of the disposal facilities. This paper explains a mathematical model which can express the saturation process. Subsequently, a series of numerical simulations were carried out. First, the swelling pressure of buffer and backfill was examined to verify the numerical model. It was confirmed that the simulated swelling pressure rises with water absorption, and swelling pressure test results from the literature are shown to be satisfactorily predicted by the numerical model, although these were slightly overestimated. Next, the mechanical behaviour of bentonite materials in a TRU waste disposal facility during the saturation process was examined using soil/ water/ air coupled finite-element method. Although it is difficult to examine the validity of analysis results because of the difficulty of an extremely long-term measurement, the qualitative behaviour of the saturation process could be inferred.

DOI： 10.1680/jenge.14.00041

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPANESE GEOTECHNICAL SOC  

Bentonite has remarkable swelling characteristics and low permeability that enhance the stability of the buffer materials in repositories for the geological disposal of radioactive waste. It is necessary to apply reliable numerical simulation techniques to assess the safety and mechanical stability of repositories over a long period of time. Having a constitutive model that can describe the mechanical behavior of bentonite is key to such numerical simulations. This paper proposes an elasto-plastic constitutive model to describe the changes in the mechanical properties of bentonite due to saturation in the progress of a repository becoming submerged under groundwater. In the proposed model, the swelling index is formulated as a function of the degree-of-saturation to express not only the swelling behavior, but also the dependency of the degree-of-saturation on the dilatancy characteristics. The montmorillonite content is used as a material parameter to determine the normal consolidation line. The experimental results of swelling volume and swelling pressure tests in previous literature are shown to have been satisfactorily predicted by the proposed model. (C) 2017 Production and hosting by Elsevier B.V. on behalf of The Japanese Geotechnical Society.

DOI： 10.1016/j.sandf.2017.01.006

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：日本語   掲載種別：研究論文（研究会，シンポジウム資料等）   出版者・発行元：地盤工学会  

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記述言語：日本語   掲載種別：研究論文（研究会，シンポジウム資料等）   出版者・発行元：地盤工学会  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.5445/KSP/1000068889

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPANESE GEOTECHNICAL SOC  

The B-value, measured after setting up a specimen for triaxial testing, is used for evaluating the degree of saturation of a specimen. However, the stress conditions used when measuring the B-value have not been standardized. Although some experimental approaches have been pursued, no detailed analyses have evaluated the effects of the measurement conditions on the B-value results. In this study, the B-values of nearly saturated specimens under various stress conditions were investigated, using a smart triaxial test apparatus capable of elaborate stress control, and comparisons among measurement results were conducted. Moreover, by applying Henry's law, which governs the dissolution of the gas phase into the liquid phase, to an existing constitutive model for unsaturated soil, a new soil model was proposed. This new model accurately represents the behaviors of pore air even under nearly saturated conditions. In addition, the effects of the stress conditions on the B-values were investigated through numerical simulations of B-value measurements. (C) 2016 The Japanese Geotechnical Society. Production and hosting by Elsevier B.V.

DOI： 10.1016/j.sandf.2016.08.009

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

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：公益社団法人 地盤工学会  

In this study, the generation process of the phreatic surface within a river levee is investigated through soil/water/air coupled simulation. Here, the effects of river level fluctuation and rainfall on changes in soil moisture distribution within a river levee are considered. The constitutive model proposed by Ohno et al.1) is formulated to the initial and boundary value problems in accordance with Borja's multi phases' concept and is used for simulation. Consequently, it is first found that high groundwater level is maintained for ground consisting of low permeability and high soil water retentivity. Moreover, it is found that the fluctuation of river level directly influences the phreatic surface, and that, in contrast, the effect of rainfall appears after a time lag.

DOI： 10.3208/jgssp.JPN-078

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：ELSEVIER SCIENCE BV  

Most onshore earth structures, such as earthen dams, embankment, and river levees, are constructed by compaction. Transportation geotechnics also includes construction of compacted earth structures, such as road and railway embankment. Optimum compaction can increase shear strength, while decreasing compressibility and permeability of earth structures. For this reason, compaction has been used for earthworks since the dawn of times. Generally, a series of lab compaction tests is conducted to obtain a compaction curve before constructing these structures. The shape of the compaction curve, which determines the maximum dry density at the optimum water content, is very important in the design and construction of structures. However, it is difficult to control compaction quality on the basis of lab tests alone, as soil materials are inhomogeneous. Furthermore, there are differences in the compaction methods used in lab tests and at construction sites. Therefore, it is necessary to explain the mechanisms of compaction in the framework of soil mechanics. In this study, compaction of earthworks is simulated in a similar way. The effect of compaction layer thickness and the number of compaction layers on the distribution of dry densities in an earth structure was investigated through soil/water/air coupled simulation. Consequently, it was found that multi-layered compaction can create a gap in the dry density between two layers and that this gap can be reduced by thinner layer compaction. On the other hand, though the average dry density in a compacted earth structure can be increased by increasing the number of compacted layers, some gap between compaction layers was inevitable. Through these findings, this study contributes to the performance design of compacted earth structures.

DOI： 10.1016/j.proeng.2016.06.035

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記述言語：日本語   掲載種別：研究論文（研究会，シンポジウム資料等）   出版者・発行元：地盤工学会  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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

低レベル放射性廃棄物のうち比較的放射能レベルの高い放射性廃棄物を対象とする余裕深度処分では，ベントナイトで構成される低透水層は人工バリアとして重要な機能を期待されている．この低透水層の設計や施工方法の検討にあたり，地下空洞内において実規模で実際に施工を行い，施工のしやすさ，実現性の確認と低透水性等の性能の確認を行うことは重要である．そこで，ベントナイトを用いた底部低透水層を対象とした，施工試験と室内試験による性能確認試験を実施した．その結果，施工のしやすさ，実現性を確認するとともに，施工後の品質として低透水層に求められる透水係数をはじめとする性能が確保可能なことを確認した．

DOI： 10.2208/jscejge.71.147

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その他リンク： https://jlc.jst.go.jp/DN/JLC/20013233950?from=CiNii

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

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

DOI： 10.2208/jscejam.71.I_171

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

近年，自然災害における被害は甚大であり，災害医療におけるDMAT (Disaster Medical Assistance Team)の役割が，人的被害最小化に大きく貢献する．しかし，情報が錯綜する災害時に医療活動を必要とする場所・規模等を掌握し，適切なDMAT派遣を行うことは難しい．そこで本研究では，過去の地震災害の経過時間に伴う累積報告死者数から導いた被災者推定式を用いて，死者数を最小にする最適化問題を考える．<br> その結果，早期派遣が有効であり，条件(DMAT数，被災地の状況)によって累積死亡者数を最小にするDMAT派遣が求められた．また，被災地状況の設定により，妥当なDMAT派遣のあり方を考察することができた．よって，チーム数に限りがあるDMATの有効的派遣のあり方を提案できることで意思決定の一助となり得ると考える．

DOI： 10.2208/jscejsp.71.32

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

災害時の不確実な情報から，意思決定者は災害対応の決断をしなければならない．この決断を下す際に「対応の迅速性」と「情報の正確性」のどちらを優先するかといった意思決定者のジレンマが存在する．この優先度の違いによって，災害対応の結果は異なってくる．そこで本研究では，災害発生後の死亡者数の時間変化をワイブル分布で近似し，逐次得られる死亡者数から最終死亡者数を求めるベイズ推定モデルを構築した．過去の地震災害事例を用いた最終死亡者数を考察することにより，災害対応の決断を下す時間帯を見積もることができ，これは意思決定者のジレンマ軽減に資するものと考える．

DOI： 10.2208/jscejsp.71.46

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/jscejam.71.i_429

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

Web of Science

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

Web of Science

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

Web of Science

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

Web of Science

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記述言語：英語   掲載種別：論文集(書籍)内論文   出版者・発行元：CRC Press  

DOI： 10.1201/b17034-76

Web of Science

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記述言語：英語   掲載種別：論文集(書籍)内論文   出版者・発行元：CRC Press  

DOI： 10.1201/b17034-91

Web of Science

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：神戸大学都市安全研究センター  

DOI： 10.24546/81011440

CiNii Books

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：神戸大学都市安全研究センター  

DOI： 10.24546/81011442

CiNii Books

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：神戸大学都市安全研究センター  

DOI： 10.24546/81011441

CiNii Books

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：神戸大学都市安全研究センター  

DOI： 10.24546/81011439

CiNii Books

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：BGR  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：GEOLOGICAL SOC PUBLISHING HOUSE  

Recently, the hydraulic/mechanical/chemical (HMC) analytical method has been studied with the aim of evaluating the long-term performance of Trans-Uranium (TRU) geological repositories. In this particular research, the hydraulic/mechanical modelling of bentonite materials for HMC analyses has been studied, with bentonite materials considered as the engineered barrier. It is said that the bentonite material in the TRU disposal facilities is altered chemically by cement leachate. Moreover, there is a concern that chemical alteration changes the expansion characteristics and water permeability of the bentonite material. In this paper, using past test results, the influence of montmorillonite content and the exchange of sodium and calcium ions on mechanical and hydraulics behaviour is examined. Hydraulic/mechanical mathematical modelling is also presented, describing the mechanical behaviour of bentonite from an initially unsaturated state while also taking into account the hydraulic and mechanical characteristics of bentonite mentioned above. We also simulate the saturation process from an initially unsaturated state in a TRU disposal facility, which is modelled one-dimensionally.

DOI： 10.1144/SP400.13

Web of Science

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記述言語：日本語   掲載種別：研究論文（研究会，シンポジウム資料等）   出版者・発行元：地盤工学会  

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

三軸試験を行う場合に，供試体設置後に計測されるB値は，供試体の飽和化の度合いを知るために用いられる．しかしながら，このB値に及ぼす要因については，飽和度以外には詳細な力学的説明は加えられていない．本論文では，極めて飽和に近い不飽和状態でも，間隙空気の挙動を精緻に表現できるように，まず既存の不飽和土構成モデルの枠組みに，空気相の液相への溶解を規定するヘンリーの法則を適用し定式化した．次に，得られたモデルを用いて，供試体の飽和度や拘束圧，背圧がB値計測に及ぼす影響を数値シミュレーションによって検討した．その結果，同じ飽和状態であっても，応力条件によって計測されるB値が異なることが分かった．

DOI： 10.2208/jscejam.70.I_145

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記述言語：日本語   掲載種別：研究論文（研究会，シンポジウム資料等）   出版者・発行元：地盤工学会  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.11345/nctam.62.141

Scopus

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1180/claymin.2013.048.2.13

Web of Science

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：神戸大学都市安全研究センター  

DOI： 10.24546/81011407

CiNii Books

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：神戸大学都市安全研究センター  

DOI： 10.24546/81011406

CiNii Books

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：神戸大学都市安全研究センター  

DOI： 10.24546/81011408

CiNii Books

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

Scopus

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.5030/jcigsjournal.28.109

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掲載種別：論文集(書籍)内論文  

© Springer Science+Business Media Dordrecht 2013. In this chapter, the stress–strain relationship on the singular point of the yield surface of the original Cam clay model and the Sekiguchi-Ohta’s model is derived in order to compute the volume change correctly. Metastable space, the range of increment of strain in which effective stress does not get away from the singular point of yield surface, was theoretically derived. In metastable space, the increment of volumetric strain is larger than the increment of deviatoric strain.

DOI： 10.1007/978-94-007-5675-5_15

Scopus

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掲載種別：論文集(書籍)内論文  

© Springer Science+Business Media Dordrecht 2013. An elasto-plastic constitutive model for unsaturated soils is improved to realize numerical stability of computations at the singular point on the yield surface and an accurate prediction of the mechanical behavior of overconsolidated (or elastic state) soils in this chapter. The authors introduce the exponential contractancy model (EC model) by Ohno et al. (J Appl Mech JSCE 9:407–414, 2006) and the subloading surface model by Hashiguchi and Chen (Int J Numer Anal Method Geomech 22:197–227, 1998) to the elasto-plastic constitutive model for unsaturated soils by Ohno et al. (J JSCE 63(4):1132–1141, 2007). The applicability of the constitutive model is verified by simulating triaxial shear tests under constant net stress undrained conditions.

DOI： 10.1007/978-94-007-5675-5_14

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

粘土の二次圧密やクリープ，ひずみ速度依存性といった時間依存性挙動を表現するため，これまで数多くの弾・粘塑性構成モデルが提案されている．しかしながら，塑性や粘性による非可逆変形を単一の物理量として評価する粘塑性論を基本とした弾・粘塑性構成モデルでは，関連流動則の適用を正当化することができず，時間経過に伴う先行効果（擬似的な過圧密挙動）も定量的に評価することができないという問題が指摘されている．そこで本研究では，飯塚・太田が提案する"塑性論的粘塑性論"を基に，時間経過に伴う先行効果を評価することが可能な拡張型の弾・粘塑性構成モデルを提案し，各種室内試験の要素シミュレーションを実施することで，提案する構成モデルの有効性および適用性について検討を行った．

DOI： 10.2208/jscejge.69.404

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その他リンク： https://jlc.jst.go.jp/DN/JALC/10024601176?from=CiNii

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：The GEOMATE International Society  

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：神戸大学都市安全研究センター  

DOI： 10.24546/81011370

CiNii Books

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：神戸大学都市安全研究センター  

DOI： 10.24546/81011372

CiNii Books

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：神戸大学都市安全研究センター  

DOI： 10.24546/81011371

CiNii Books

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：神戸大学都市安全研究センター  

DOI： 10.24546/81011374

CiNii Books

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

This study presents a new constitutive model for expansive soils. Under any arbitrary state of degree-of-saturation, the mechanical void ratio predicted by the elasto-plastic constitutive models, i.e. EC model and Se-hardening model are combined with the additional void ratio in order to characterize the typical swelling behavior of expansive soil. Herein, the fully saturation curve which derived from compaction and consolidation experimental tests are taken into consideration. The proposed model is examined by simulating the typical experimental test on expansive soil, i.e. normally consolidation and swelling pressure tests. © 2012 IEEE.

Scopus

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/jscejam.68.i_345

J-GLOBAL

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

Compacted soil is widely used for earth structures. However, the mechanism of compaction has not been explained, so it is difficult to grasp distributions of stress, void ration, and soil moisture within compacted earth structure. Therefore, estimation of safety and stability of compacted earth structures exposed to natural disaster is complicated. Compaction is decreasing void ratio by applying stress under certain water content and pushing air out of soil mass. Thus, the mechanics of unsaturated soil, which includes air within void, is needed for understanding of compaction. In this study, we regarded compaction as compression and expansion phenomenon of unsaturated soil under drained air and undrained water conditions and formulated it in initial-boundary-value problem. Here, the influences of permeability and soil water retention characteristics on compaction were considered and static compaction tests were simulated. Moreover, multi-layered compaction was examined.

DOI： 10.2208/jscejam.68.I_299

J-GLOBAL

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/jscejam.68.i_291

J-GLOBAL

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/jscejam.68.i_307

J-GLOBAL

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：論文集(書籍)内論文   出版者・発行元：Springer Berlin Heidelberg  

DOI： 10.1007/978-3-642-31343-1_23

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

Thermal power plants burn oil and coal to generate electricity. Coal fly-ash is a product of the coal-burning process. Coal fly-ash has a self-hardening property and becomes extremely stiff over time. For this reason, it is being reused as a concrete aggregate in the production of concrete. Recently, coal-fly ash is being mixed with soil from construction waste for reclamation projects. To be able to reuse coal fly-ash in such a way, in the field of geotechnical engineering, the associated self-hardening properties must be incorporated in the framework of the constitutive model. It is generally known that cemented soil, such as fly-ash, behaves similar to unsaturated soil. In the constitutive model for unsaturated soil, hardening due to desaturation is expressed as the increase in yield stress. Here, changes in parameters used in the Cam-Clay model, generated by this self-hardening property, are studied by comparing the simulation results obtained from a soil/water coupled analysis with triaxial test results on two kinds of coal fly-ash. Consequently, the self-hardening property is expressed as an increase in the yield stress and an increase in the frictional angle, dependent on time. Differences between the two methods of producing fly-ash are reflected in the parameter set.

Scopus

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.3233/978-1-60750-822-9-924

Web of Science

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/jscejam.67.i_231

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：神戸大学都市安全研究センター  

DOI： 10.24546/81011336

CiNii Books

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：神戸大学都市安全研究センター  

DOI： 10.24546/81011340

CiNii Books

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：神戸大学都市安全研究センター  

DOI： 10.24546/81011337

CiNii Books

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：神戸大学都市安全研究センター  

DOI： 10.24546/81011338

CiNii Books

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：神戸大学都市安全研究センター  

DOI： 10.24546/81011339

CiNii Books

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

An evaluation method for the mechanical behavior of unsaturated soils is studied in this paper. Although the mechanical behavior of unsaturated soils is complicated, a simple modeling is preferable in practice. This is because the soil properties are not homogeneous and ground data is limited when structures are being designed. In addition, in order to evaluate the reliability of the design, the physical meanings of the parameters applied in the prediction model should be clear. Firstly, the authors study the relationship between compaction curves and compression indexes in the unsaturated state that is used in the proposed constitutive model. Based on the constitutive model, the stress paths for constant volume shear tests are formulated under a constant void ratio condition and the stress paths for undrained shear tests are calculated under a constant water content condition. In the case of unsaturated specimens, the volume of these specimens changes with the shear deformation and the stress paths depend on the initial degree of saturation. The results of the calculation qualitatively describe the test results by considering the changes in effective confining pressure in the undrained condition and the water retention curves. © 2010 Springer Science+Business Media B.V.

DOI： 10.1007/s10706-010-9340-6

Scopus

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

Due to its low permeability and excellent expansion characteristics, bentonite is an excellent candidate with potential use as a buffer in the disposal of nuclear waste. Its expansion characteristics, activated by wetting, can be interpreted based on the full saturation line, depicted as a unique line on the density and the confining pressure relationship as proposed by Kobayashi et al. (2007). In addition, its elasto-plastic constitutive relation can also be formulated by introducing additional irreversible strain component describing the expansion of the montmorillonite present in the bentonite material. A constitutive model can consistently express the mechanical behavior of the compacted bentonite material from the unsaturated to the fully saturated state. This paper describes the density homogenization process that was conducted through a series of soil-water coupled elasto-plastic finite element simulations. Specifically, bentonite specimens, with different initial densities, were permeated with a constant water head. Stresses and strains developing in bentonite, particularly the density change, were carefully examined. A series of numerical simulations, performed on the two specimens, showed that specimens did not homogenize to a unique value of density upon reaching the fully saturated state. To confirm the simulation results, we carried out a series of experiments. The experimental results also support our simulation results. Copyright © 2011 by ASME.

DOI： 10.1115/ICEM2011-59153

Scopus

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.jmps.2010.07.013

Scopus

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

Desertification due to salt damage has recently become a serious problem throughout the world. Salt damage is a phenomenon where salt in the groundwater gets concentrated at the ground surface and kills vegetation. In this study salt damage due to disequilibrium of water balance was simulated with unsaturated soil/water coupled simulation code, as applied the material transport equation. Evaporation and precipitation cycles were applied to a model of ground that contained salty groundwater in its deep region. This allowed the successful reproduction of the phenomenon of salt accumulation on the ground surface. Additionally, identical climatic conditions were applied to model grounds consisting of two types of soil, different in terms of their soil-water retention characteristics. It was found that two methods of overlay and insertion of a layer of coarse-grade material, known as 'mulching', are effective in the prevention of salt accumulation. © 2011 Taylor & Francis Group, London.

Scopus

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Scopus

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

Web of Science

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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

CiNii Books

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

Web of Science

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：土木学会  

CiNii Books

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.11345/nctam.57.89

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：JSCE  

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

CiNii Books

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

It is empirical knowledge that vegetation can influence the behavior of earth structure. It prevents surface failure and erosion due to rain and wind, and contributes to the stability of earth structure. Moreover, it encourages water circulation with transpiration, fixes atmospheric nitrogen and carbon via photosynthesis, and improves the environment. Therefore, surface seeding is purposely performed when an earth structure, such as an embankment or an earth dam, is constructed. Typically, vegetation grows on unsaturated soil. Consequently, a constitutive model for unsaturated soil is needed for understanding the effects of vegetation on the ground. In this study, we focus on the effect of vegetation-induced water uptake. The effect of water uptake due to evapo-transpiration can be regarded as reduction of water content within soil and appropriately represented in simulation studies. The constitutive model proposed by Ohno et al. (2007) is used for the simulation. In this model, the effective degree of saturation is treated as a parameter expressing hardening/softening. Moreover, the 'root element,' where the reduction of water content occurs, is applied to the soil/water coupled analysis with unsaturated soil mechanics. To verify the applicability of this model, the accident in Poland where non-uniform settlement and building damage were caused by water uptake of vegetation was simulated. The results show that water uptake increased suction and induced non-uniform settlement. This method is effective for understanding the effects of vegetation on the ground. © 2009 IOS Press.

DOI： 10.3233/978-1-60750-031-5-526

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/jscejeep.1.135

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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

CiNii Books

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

CiNii Books

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記述言語：英語   掲載種別：論文集(書籍)内論文   出版者・発行元：CRC Press  

DOI： 10.1201/9780203885949.ch52

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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

CiNii Books

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPANESE GEOTECHNICAL SOC  

The soil/water-coupled analysis for unsaturated soil mechanics with the finite element method is used to express the behavior of compacted earth structures exposed to rainfall. The constitutive model, which is proposed by Karube et al. (1996, 1997) and modified by Karube and Kawai (2001), is formulated for initial and boundary problems and coded as DACSAR-U (lizuka et al., 2000). A deep fill, which consists of compacted, unsaturated soil, was analyzed with DACSAR-U. Different patterns of rainfall were applied to deep fills in finite element simulations. As a result, non-uniform settlement of deep fill can be calculated and the magnitude of settlement of deep fills is dependent on the amount of collapse, namely, the compression due to the decrease in suction. Moreover, delayed settlement due to rainfall and an accumulation of an irreversible settlement due to cyclic rainfall was observed.

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

A new constitutive model of swelling soil material is proposed to evaluate its mechanical characteristics. In the case of the compacted bentonite material, nonlinear behavior appears more dominantly than ordinary clay materials in the consolidation test. The original Cam-clay model cannot describe these characteristics observed in the compacted bentonite materials. Therefore, a new modeling that strain increment consists of linear summation of the swelling component and the elast-plastic component is introduced to describe the nonlinear behavior in the unloading stage. From the result of the simulation of the triaxial compression test, it is demonstrated that the stress pass and the stress and strain relationship are well simulated by the new model.

DOI： 10.2208/jsceseee.24.102s

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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

DOI： 10.2208/journalam.10.971

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：MILLPRESS SCIENCE PUBLISHERS  

In this paper, the authors focus on the confining effect brought by geosynthetic-reinforcement. The reinforcement effect is not brought by the geosynthtics itself but mobilized complexly as a composite material consisting of geosynthetics and compacted soils. If the geosynthetics and the compacted soils are unified more tightly, higher reinforcement effect may be expected. Then, in this paper, presented is an experiment, that is, making soil cantilevers with compacted soils wrapped by geosynthetics which are tightly unified by prestressed steel bars. Two types of soil cantilevers were constructed. The soil structures were, first, constructed and wrapped by geosynthetics on the bases of styrene forms and, next, prestressed through the steel bars penetrated from the top surface to the bottom of the geosynthetic-reinforced soil structures. The soil cantilever was formed by melting and removing the styrene forms in order from the edge with monitoring the vertical displacements. It was found that amazing reinforcement effect appears by tightly confining the dilative deformation of compacted soils with the geosynthetics and the prestressed steel bars. The reinforcement effect is numerically investigated. A series of elasto-plastic FE numerical simulation was carried out. The compacted soil was modelled to be elasto-plastic body and the geosynthetics was expressed by the elastic material.

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

This paper discusses the volume change characteristics of compacted soil based on oedometer test results. After making specimens with different water contents and under different compaction loads, compression tests are conducted under both saturated and unsaturated conditions. The effects of the compaction conditions on the compression curves are discussed. It is confirmed that the yield stress and the water content are important factors when evaluating a compression curve, while dry density and suction are important factors when evaluating the yield stress. Copyright ASCE 2006.

DOI： 10.1061/40802(189)66

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：神戸大学  

CiNii Books

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：地盤工学会  

Changes in the instantaneous shear modulus associated with the non-coaxiality of NC clay materials are presented. A series of hollow cylindrical shear tests was performed to measure the changes in the instantaneous shear modulus with shear history. After each normally consolidated clay specimen was compressively sheared until a prescribed shear level, it was continuously torsionally sheared under a constant volume to measure the instantaneous shear modulus. Coaxial constitutive relations, such as these of the conventional Cam-clay type of models, predict that the instantaneous shear modulus obtained, does not change regardless of the compressive shear history. On the contrary, it is known that non-coaxial constitutive relations theoretically bring about changes in the instantaneous shear modulus in relation to the compressive shear history. The test results supported the predictions made by the non-coaxial constitutive models. Finally, the proper formulation for the non-coaxiality between the stress and the incremental plastic strain is discussed.

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その他リンク： http://dl.ndl.go.jp/info:ndljp/pid/10424246

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPANESE GEOTECHNICAL SOC  

Changes in the instantaneous shear modulus associated with the non-coaxiality of NC clay materials are presented. A series of hollow cylindrical shear tests was performed to measure the changes in the instantaneous shear modulus with shear history. After each normally consolidated clay specimen was compressively sheared until a prescribed shear level, it was continuously torsionally sheared under a constant volume to measure the instantaneous shear modulus. Coaxial constitutive relations, such as these of the conventional Cam-clay type of models, predict that the instantaneous shear modulus obtained, does not change regardless of the compressive shear history. On the contrary, it is known that non-coaxial constitutive relations theoretically bring about changes in the instantaneous shear modulus in relation to the compressive shear history. The test results supported the predictions made by the non-coaxial constitutive models. Finally, the proper formulation for the non-coaxiality between the stress and the incremental plastic strain is discussed.

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：TAYLOR & FRANCIS LTD  

The prediction of back-fill settlement due to the excavation work is getting important, particularly in the urban area. The finite element simulation would be a suitable choice to answer it. However, it is less feasible in practice to carry it out because input parameters needed in the F.E. simulation are not sufficiently provided in advance at the stage of design work. In the past, some simple evaluation methods for predicting the back-fill settlement due to excavation works were presented by Peck, Long and Moormann et al. and so on. In this paper, a new method capable for predicting the back-fill settlement at the stage of design work is proposed, taking account of design parameters, i.e. soil parameters, retaining wall parameters and construction sequences. The proposed method is built up based on a lot of monitored records obtained from sites and the numerical results obtained from a series of F.E. simulations for imaginary excavation works. It is designed to be simple and useful at the stage of design work. This method consists of two parts, predictions of the maximum amount of back-fill settlement and the distance from the retaining wall. Finally, some case studies in which the proposed new method was applied to actual excavation sites in Japan are presented.

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

This paper presents the modeling of the composite soil-geosynthetic structure and discusses the effect of the reinforcement arising from the confining of the deformation of the soil by geosynthetics. A series of compressive shear tests for compacted sandy soil specimens, wrapped in geosynthetics, is carried out for the purpose of quantitatively examining the effect of the geosynthetic reinforcement arising from the confining of the deformation of compacted soils during shearing. Furthermore, an elasto-plastic modeling for compacted soil and a rational determination procedure for input parameters, needed in the elasto-plastic modeling, are presented. In this paper, the subloading yielding Surface is introduced to the elasto-plastic modeling in order to describe the irreversible deformation characteristics of compacted soil during shearing. Since compacted soil is essentially unsaturated and its mechanical behavior is influenced by the suction working in the compacted soil media, the suction effect is taken into account in estimating of the degree of compaction. Finally, an elasto-plastic finite element simulation is conducted and the geosynthetic-reinforcement effect is presented. (C) 2004 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.geotexmeml.2004.01.001

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

There are some constitutive models for unsaturated soil. However, their mathematical structures, particularly for expression of collapse phenomenon, are essentially the same. Therefore, it is possible to unify the constitutive models which were proposed in the past. In this paper, a generalized constitutive model for unsaturated soils is presented. First, we outline existing constitutive models for unsaturated soil and, next, we propose a comprehensive constitutive model for unsaturated soils in terms of the effective stress for unsaturated soils. To this new elasto-plastic model, it is easier to introduce sophisticated methods such as a rotational hardening, a subloading surface and so forth. This model is formulated in the form of incremental general stress and strain relationship and is incorporated into a finite element code, DACSAR-U, for unsaturated soils. The performance of the new constitutive model is demonstrated by comparing with the models proposed by Karube et at and by Honda et al

DOI： 10.2208/journalam.7.505

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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出版者・発行元：公益社団法人 地盤工学会  

DOI： 10.11512/jiban.JGS39.0.259.0

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出版者・発行元：公益社団法人 地盤工学会  

柴田(1963)、柴田・軽部(1965)、太田・畠(1971)による一連の研究によって提案された弾塑性構成式(太田・畠モデル)において、土のダイレイタンシー挙動は、間隙比(e)と応力比(q/p')との関係において直線としてモデル化されている。しかし、これまでの研究により、土によっては、その関係が必ずしも直線とならないことがわかっている。本研究では、柴田(1963)、柴田・軽部(1965)、太田・畠(1971)による一連の研究を踏襲しながら、より適用性の高いダイレイタンシーの表現式を提案することで、新しい土の弾塑性構成式を導出している。

DOI： 10.11512/jiban.JGS39.0.261.0

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出版者・発行元：公益社団法人 地盤工学会  

これまで,土構造物の挙動予測を行う際に関口・太田による弾(粘)塑性構成モデルが組み込まれた二次元土/水連成弾(粘)塑性有限要素解析プログラム(DACSAR)が多く用いられてきた.しかし,現行のDACSARで適用されている負荷判定法は粘塑性体積ひずみと定める閾値の大小関係で行われているため,閾値の定め方によって負荷判定結果が左右される.そこで,本報告は飯塚らが提案した閾値を必要としない負荷判定法をDACSARに組み込み,K0圧密および静的非排水繰返しせん断の解析結果を比較することにより,新しく提案した負荷判定法の適用性について検討したものである.

DOI： 10.11512/jiban.JGS39.0.913.0

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPANESE GEOTECHNICAL SOC  

A highway embankment built in Akita prefecture using ground stabilization methods was constructed on very soft peat and clay deposits on a sloping base. This paper presents a case study of a soil/water coupled elasto-viscoplastic finite element simulation of an actual embankment construction, that is, the deformation analysis of a soft clayey foundation deposited on an inclined base with embankment loading. For execution of the numerical simulation, determining the input parameters needed in the analysis and evaluating the shape of sloping bedrock under the ground were problems. The former is discussed for a practical procedure of determining input parameters using unconfined compression strengths and the latter is accomplished by drawing a contour map of the top face of the bedrock under the ground, with reference to the geographical features of the area around the site and to a topographic map. The performance of the numerical simulation is discussed in comparison with in-situ monitored records. The effectiveness of ground stabilization methods employed at the site is also a topic of discussion.

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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

CiNii Books

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPANESE GEOTECHNICAL SOC  

Experimental evidence suggests that a mutual relationship between anisotropy and structure of clays exists. It was hypothesized that development and decay of the structure of clays (called structuralizing and destructuralizing) can be regarded as development of anisotropy and decay of anisotropy (isotropization), respectively. Using this hypothesis, an anisotropic rotational hardening rule was incorporated in the Sekiguchi-Ohta elasto-plastic constitutive model. The subloading surface concept was also introduced to model the plastic deformation inside the yield surface more accurately.
The proposed model provided some rational as well as physical explanations for the experimental facts. Using the proposed model, it was possible to simulate the apparent softening behavior observed in anisotropically consolidated specimens. For isotropically consolidated specimens, no softening was observed, which is consistent with the experimental data. At the critical state, the undrained shear strength of the anisotropically consolidated specimens was the same as that of the isotropically consolidated specimens. This is due to both specimens having the same soil structure after large shearing. The shape of yield surface obtained from stress probe tests was investigated by simulating the tests with the proposed model. Typical data of the stress probe tests of natural clays shows that the yield surface generally has a smooth elliptical shape. By modeling the rotation of yield surface, the proposed model was capable of simulating this 'apparent' yield surface.

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：論文集(書籍)内論文  

DOI： 10.1201/9781439833919.ch45

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出版者・発行元：公益社団法人 地盤工学会  

本研究の目的は,室内試験を境界値問題と捉え,正規圧密粘土の非排水三軸圧縮・伸張試験,平面ひずみ圧縮試験をシミュレーションし,供試体の破壊挙動を解析的に検討することである.計算を行う道具として,有限変形弾塑性理論に基づく土/水連成3次元有限要素プログラムを開発した.シミュレーションにはMises型のCam-clayモデルを用いているため,解析解として得られる破壊強度に圧縮側,伸張側あるいはその中間で違いがあれば,一般に実験で得られるMohr-Coulombの規準は粘土の材料としての性質ではなく,他の要因に起因するものと考えられる.

DOI： 10.11512/jiban.JGS38.0.293.0

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出版者・発行元：公益社団法人 地盤工学会  

既存のモデルでは,構造・過圧密の変化を表す概念として上・下負荷面モデル,異方性の変化を表す概念として回転硬化則を用いていたが,両者の関係に関しては十分な議論がなされていなかった.本研究では,構造の劣化と異方性の変化には不可分な関係があると考え,関口・太田モデルに上・下負荷面の概念と回転硬化則を導入し,構造・過圧密・異方性の変化を統一的に取扱える構成モデルを開発した.具体的には,回転硬化の発展則を上負荷面の発展則の関数で表すことによって,構造と異方性を結びつけた.開発した構成モデルを用いて,構造を持った土の各種室内力学試験を解析し,これまで表すことができなかった実験事実を説明し,妥当性を示した.

DOI： 10.11512/jiban.JGS38.0.283.0

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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

DOI： 10.2208/journalam.5.785

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記述言語：日本語   掲載種別：研究論文（研究会，シンポジウム資料等）  

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

The mechanical behavior of unsaturated soils strongly depends on the pore water distribution as well as the suction. The water characteristic curve (W. C. C) specifying the pore water content and the suction value plays a very important role in describing the mechanical modeling for unsaturated soils. However, the W. R. 0 shows the hysteresis loop in the wetting/drying processes. This paper emphasizes the importance of considering the hysteresis of W.C.C in the modeling. The accumulation of irreversible strains in the soil structures caused by rainfalls cannot be explained well without considering the hysteresis of W. C. C. An existing model of W. C. C is modified so as to express the accumulation of irreversible strains as the cyclic suction loading. Finally, it is shown that the modified model well explains the experimental results.

DOI： 10.2208/journalam.5.777

CiNii Books

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

CiNii Books

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）   出版者・発行元：神戸大学都市安全研究センター  

DOI： 10.24546/00317653

CiNii Books

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

DOI： 10.2208/journalam.5.601

CiNii Books

J-GLOBAL

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記述言語：英語   出版者・発行元：公益社団法人 地盤工学会  

DOI： 10.11512/jiban.JGS37.0.761.0

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出版者・発行元：公益社団法人 地盤工学会  

DOI： 10.11512/jiban.JGS37.0.327.0

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出版者・発行元：公益社団法人 地盤工学会  

DOI： 10.11512/jiban.JGS37.0.325.0

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：A A BALKEMA PUBLISHERS  

The reinforcement technique using flexible materials such as geosynthetics has been widely employed in the current engineering practice. However, the reinforcement mechanism has not revealed sufficiently, i.e. the mechanical interaction between the reinforcements and soils, the confining effect induced by reinforcements and so forth, and then it has not yet led into a proposal of rational design procedure. This paper reports in-situ loading tests carried out on the compacted soil structure reinforced by flexible beltlike materials. Elasto-plastic finite element simulations were also performed considering dilatancy characteristics of compacted soils during shearing. Throughout comparison with the field records monitored in the site and the results obtained from the conventional elastic computation, discussed are the applicability of the elasto-plastic analysis and the role of dilatancy characteristics of compacted soils in the reinforcement mechanism.

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

CiNii Books

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

CiNii Books

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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

本論文では, ジオシンセティックスによる補強効果を定量的に検討することを目的に, モデル実験および有限要素シミュレーションを実施している. 土を円柱形状に締固め, その外周が簀巻き状にジオシンセティックスで覆われている. このような供試体に外力を載荷し, 供試体の変形とジオシンセティックスに作用する力を調べている. 土の締固め度合いを変えた実験を行い, 土の変形と補強効果の関係を調べている. さらに, このような補強材と締固め土の力学的相互作用を模擬できる有限要素解析手法を提案している. ジオシンセティックス補強材に作用する力は, 締固め土のダイレイタンシー変形を拘束することによって生じ, 締固め度合いの違いにより, ジオシンセティックスによる補強効果に差が生じることがわかった.

DOI： 10.2208/jscej.2001.680_15

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.11345/japannctam.tam51.0.91.0

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2208/jscej.2001.694_67

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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

CiNii Books

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：A A BALKEMA PUBLISHERS  

Apart from following general outlines for input procedures and parameter findings when performing excavation analysis using FEM, some additional considerations should be taken. The influences of appropriate soil stiffness, pre-load efficiency, actual strut stiffness, soil/wall interface, crack in concrete retaining wall, and foundation piles installed before excavation have been investigated to weight the impact on analysis quality, enhancing acceptability in practice. Computed deformations and strut axial loads of a case study agreed quite well with field responses after applying these effects.

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

CiNii Books

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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記述言語：日本語   出版者・発行元：公益社団法人 土木学会  

開削工法などの掘削工事では, 周辺地盤や構造物に及ぼす変形が大きな問題となる場合がある. 特に都市部における掘削工事では周辺構造物の密度は増す一方であり, 十分な検討が必要となる. しかし, 土留め工設計に関わる各規準においては具体的な検討手法を記述したものは少なく, どのような方法が優れているか, 未だ定見はない. また, 比較的煩雑な手法が多く, 設計時に得られている少ない情報から容易に周辺地盤の変形を予測する手法が求められる. 本研究は, モデル地盤による有限要素法解析結果と現場で計測されたデータから求めた周辺地盤への変形の影響要因を評価し, 設計計算に用いるパラメータ (主としてN値および土留め壁の剛性) を用いて, 掘削時の周辺地盤変形を簡便に予測するための新しい手法を提案するものである.

DOI： 10.2208/jscej.2000.652_217

CiNii Books

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：A A BALKEMA PUBLISHERS  

The specification of strength parameters is an important task in the design work of slope stability. Usually laboratory shear tests are employed to determine the strength parameters. The specimen in the laboratory tests is intended and generally assumed to represent a single point in the in-situ soil medium. And, the strength parameters obtained are interpreted as material properties of the soil element. However, since the uniformity of stress/strain distribution within the specimen is hardly achieved during shearing, the strength parameters thus obtained cannot be essentially regarded as material properties. In this paper, the shear box test under the condition of constant volume is considered and the distribution of stress/strain within the specimen is rigorously examined through numerical simulations based on finite incremental deformation theory. The mobilization of strength is explained associated with the development of shear bands in the specimen during shear.

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：A A BALKEMA PUBLISHERS  

The strain localization developing inside clay specimens during shear is examined through the experimental observation and numerical F.E. simulation. In the experiment, clay specimens of column and hollow-cylinder shapes are uniaxially sheared and the development of shear bands is observed. The numerical simulation of compression shear is carried out under the plane strain condition for normally consolidated clay specimens with impermeable boundaries by using the elasto-plastic soil/water coupled finite element computation technique based on the finite deformation theory. Although the geometric boundary conditions are different in the experiment and simulation, discussed are the development of shear bands on/in the specimen and the transition of the localization mode which are found commonly in the experiment and simulation.

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：A A BALKEMA PUBLISHERS  

This paper presents evaluation of undrained strengths obtained from unconfined compression tests, constant volume shear box tests and field vane shear tests which were carried out in a site. Theoretical expressions of these undrained strengths derived from the elasto-plastic constitutive model are summarized. And discussed are the correction factors that help converting the undrained strengths obtained from tests to ideal undrained strengths comparable to the theoretical strengths. Throughout comparison of the measured strengths and the theoretical predictions, reliable specification of the constitutive parameters for the model from the measured strengths is examined.

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：A A BALKEMA PUBLISHERS  

Mechanical properties of soft clays, such as deformability and strength, are estimated using data obtained from in-situ and laboratory tests. These test methods were developed through experience gained in the development of geotechnical engineering. The undrained strength, for instance, of a soft clay estimated by using any one of these in-situ or laboratory tests is not usually the same as that estimated by another one of these tests. There are many possible reasons for the apparently different response of the clay to each of these testing methods. The differences caused by factors such as disturbance, stress history, detailed testing procedures, are sometimes surprisingly influential. This paper shows examples of the above mentioned complications encountered in engineering practice. The paper also describes the interpretation of such complications by means of an elasto-plastic constitutive model which was proposed by Sekiguchi and Ohta in 1977.

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：A A BALKEMA PUBLISHERS  

The seismic deamplifying effect of soft clay layers is described. This deamplifying effect of soft clay layers on the propagated waves due to an earthquake is significantly influenced by the degree of consolidation of the soft clay underlying the site. In this paper, two buildings on Rokko Island are analysed. First, the static soil/water coupled analyses are carried out to assess the initial equilibrium conditions of the site just before the earthquake and, secondly, the dynamic response analyses are performed based on the data obtained from the static analyses. The emphasis is placed on evaluating the factor of safety against liquefaction at the various stages of consolidation and at the completion of consolidation. The results seem to be consistent with the overall phenomena observed in Port island and Rokko Island.

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記述言語：日本語   掲載種別：研究論文（研究会，シンポジウム資料等）  

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記述言語：日本語   掲載種別：研究論文（研究会，シンポジウム資料等）  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：A A BALKEMA  

A full-scale model test was conducted to investigate the mechanism of soil reinforcement by geosynthetic materials, A beam shaped soil structure reinforced by geosynthetics was designed and the global momentum stiffness was examined. This paper presents a brief description of the theoretical estimate of the global momentum stiffness of the reinforced structure for the laboratory model test and the numerical simulation of the full scale model test. The numerical simulation and the field test indicate that the effect of soil confinement by the geosynthetic material was particularly significant. A comparison of the numerical and field results is also presented.

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記述言語：日本語   掲載種別：研究論文（研究会，シンポジウム資料等）  

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記述言語：日本語   掲載種別：研究論文（研究会，シンポジウム資料等）  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：日本語   掲載種別：研究論文（研究会，シンポジウム資料等）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：A A BALKEMA  

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記述言語：日本語   掲載種別：研究論文（研究会，シンポジウム資料等）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：日本語   掲載種別：研究論文（研究会，シンポジウム資料等）  

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記述言語：日本語   掲載種別：研究論文（研究会，シンポジウム資料等）  

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記述言語：日本語   掲載種別：研究論文（研究会，シンポジウム資料等）  

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記述言語：日本語   掲載種別：研究論文（研究会，シンポジウム資料等）  

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

3次元土/水連成FEMにより, 原位置ベーンせん断試験で予想されるベーン孔壁近傍での部分排水および材料粘性の影響を調べている. 非排水条件が完全に満足されて, しかも十分に遅い速度でせん断された時 (理想的なベーンせん断試験) には, ベーン端面と側面とで強度に差はない. しかし, 部分排水と材料特注の影響の度合いが, ベーン端面と側面とで異なるため, 結果として, それぞれの強度がことなってくることがわかった.

DOI： 10.2208/jscej.1994.487_227

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：A A BALKEMA PUBLISHERS  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：THOMAS TELFORD SERVICES LTD  

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

This paper describes the effect of non-coaxiality arising from material anisotropy on bifurcation phenomena such as shear band formation. The elasto-plastic model originally proposed by Sekiguchi and Ohta [7] is one of the typical models which include anisotropy and it is used to examine the effect of anisotropy on shear band formation. First, we shall extend this elasto-plastic model for infinitesimal strain to a model for finite strain and discuss the mathematical structure of this model. The stress induced anisotropy is found to bring about a vertex-like effect, such as the non-coaxiality between the Cauchy stress tensor and a plastic stretching tensor, into the constitutive relation. Then, we shall examine the effect of this non-coaxiality on bifurcation conditions in relation to the material rigidity which changes with the angle of simple shear. Finally, it will be concluded that this non-coaxiality arising from the anisotropy does not contribute much to triggering instability by localization of the deformations which result in shear band formation, while on the other hand, the non-coaxiality due to the yield vertex effect is rather inclined towards instability by localization of the deformations.

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：A A BALKEMA  

Web of Science

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：A A BALKEMA  

Web of Science

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：A A BALKEMA  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：日本語   掲載種別：研究論文（研究会，シンポジウム資料等）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：THOMAS TELFORD SERVICES LTD  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：日本語   掲載種別：研究論文（研究会，シンポジウム資料等）  

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記述言語：日本語   掲載種別：研究論文（研究会，シンポジウム資料等）  

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記述言語：日本語   掲載種別：研究論文（研究会，シンポジウム資料等）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：日本語   掲載種別：研究論文（研究会，シンポジウム資料等）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

Web of Science

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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

Coupled elasto-plastic deformation-flow finite element analysis has been frequently used for the prediction of displacements, stresses and pore water pressures in geotechnical problems. However, the analysis is not suitable for the stability problems since its numerical results often become unstable after the stress paths of elements arrive at the critical state.<br>The analytical method including &ldquo;imaginary viscosity method&rdquo; which is a usual viscoplasticity computation scheme is developed to analyse the behavior of soil from the initial stress stage to the failure one.<br>In order to assess the validity and the applicability of this method, a problem of bearing capacity and an actual embankment are examined.

DOI： 10.2208/jscej.1987.388_121

CiNii Books

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

DOI： 10.3208/sandf1972.27.3_71

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

The finite element technique using the imaginary viscoplastic calculation scheme is employed to compute the perfect plasticity region such as failure state. And the calculation of bearing capacity of footing in anisotropic normally consolidated ground is performed by incorporating theoretical equation of anisotropic undrained shear strength into yield function. The influences of anisotropy of ground are analytically investigated with taking notice of stress distribution near and in the applied footing stress at collapse of ground.

DOI： 10.2208/jscej.1987.382_255

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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総ページ数：294   担当ページ：pp.231-251   記述言語：英語   著書種別：学術書

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担当ページ：p.82 pp.128-137   記述言語：日本語   著書種別：学術書

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記述言語：日本語   著書種別：教科書・概説・概論

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記述言語：英語  

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記述言語：日本語   著書種別：学術書

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記述言語：日本語   著書種別：学術書

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記述言語：日本語   著書種別：学術書

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記述言語：日本語   著書種別：学術書

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記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）  

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記述言語：日本語  

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記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）  

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記述言語：日本語   掲載種別：記事・総説・解説・論説等（その他）  

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記述言語：日本語  

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記述言語：日本語  

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