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M. Hyodo - One of the best experts on this subject based on the ideXlab platform.
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On the critical state characteristics of Methane Hydrate-bearing sediments
Marine and Petroleum Geology, 2020Co-Authors: Yang Wu, M. HyodoAbstract:Abstract Reasonable prediction of marine ground stability is vital for the safe exploitation of Methane gas from the seabed and development of relevant technologies for gas production. Constitutive models based on a critical state soil mechanics framework for Methane Hydrate-bearing sediments have been proposed in recent decades. They required careful calibration of laboratory results to obtain accurate information on model parameters. This study presents a comprehensive analysis of triaxial shear test data to examine the effects of Hydrate saturation on the geomechanical characteristics of Methane Hydrate-bearing sediments, particularly at the critical state. Multiple critical state lines are identified for Methane Hydrate-bearing sediments with different levels of Hydrate saturation on the specific volume and logarithm of mean stress plane. A rise in Hydrate saturation shifts the critical state line of Methane Hydrate-bearing sediments upward and slightly increases the gradient of critical state line in the v − ln p ′ plane. Non-unique critical state lines are observed for Methane Hydrate-bearing sediments under plane-strain loading conditions. Considering Methane Hydrate saturation as an extra dimension of critical states, the critical state line in the plane of specific volume and logarithm of mean stress, becomes a three-dimensional critical state surface.
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DEM modelling of Methane Hydrate bearing sand
2015Co-Authors: Jayan S. Vinod, M. Hyodo, Buddhima Indraratna, Roy MillerAbstract:Methane gas Hydrates are crystalline compounds formed from water and Methane under certain pressure and temperature. They are mostly found in marine continental margin sediments and beneath the permafrost and considered as the future non-conventional energy resource. In order to develop innovative techniques for the safe extraction of Methane gas from Methane Hydrate (MH) it is important to understand the shear behaviour of Methane Hydrate bearing sand. It has been reported that the pore scale habits of MH have a significant influence on the shear behaviour of Methane Hydrate bearing sand. In this paper, an attempt has been made to capture the effect of pore scale habits on the shear behaviour of Methane Hydrate bearing sand using the Discrete Element Method. Two modelling approaches (i) pore filling, leading to load bearing, and (ii) cementation, bonding of the interparticle contact, have been simulated using PFC3D. A series of triaxial monotonic tests were carried on an assembly of particles for different Methane Hydrate saturations. Both the approaches have captured, qualitatively, the stress ratioaxial strain behaviour similar to the laboratory experiments. The DEM simulation results highlight that MH saturation has a profound influence on the shear behaviour of Hydrate bearing sand. It was shown that the cementation habit closely captures the variation of peak deviator stress with MH saturation similar to the laboratory experiments. Moreover, the evolution of micro-mechanical parameter (e.g. contact force and bond breakage) during shear loading has been presented and discussed. Disciplines Engineering | Science and Technology Studies Publication Details Vinod, J. S., Hyodo, M., Indraratna, B. & Miller, R. K. (2014). DEM modelling of Methane Hydrate bearing sand. Australian Geomechanics Journal, 49 (4), 175-182. This journal article is available at Research Online: http://ro.uow.edu.au/eispapers/3417 DEM MODELING OF Methane Hydrate BEARING SAND J. S. Vinod, Masayuki Hyodo, Buddhima Indraratna & Roy Miller Centre for Geomechanics and Railway Engineering, University of Wollongong, NSW Australia Department of Civil & Environmental Engineering, Yamaguchi University, Japan
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effects of dissociation on the shear strength and deformation behavior of Methane Hydrate bearing sediments
Marine and Petroleum Geology, 2014Co-Authors: M. Hyodo, Yanghui Li, Yukio Nakata, Norimasa Yoshimoto, Jun Yoneda, Akira NishimuraAbstract:Abstract A series of tests were conducted in order to investigate the shear strength and deformation behavior of Methane Hydrate-bearing sediments during dissociation using the thermal recovery method or depressurization method. An innovative temperature-controlled high pressure triaxial apparatus which can reproduce the in situ conditions of Hydrate reservoirs was used. The results indicate that: (1) the failure strength of isotropically consolidated Methane Hydrate-bearing sediments which dissociated completely using the thermal recovery method is less than that of pure Toyoura sand. However, the initial stiffness and volumetric strain are higher than that of pure Toyoura sand. (2) The thermal recovery method will cause the failure of Methane Hydrate-bearing sediments when the axial load is higher than the strength of Methane Hydrate-bearing sediments after dissociation. (3) The depressurization method will not cause collapse of Methane Hydrate-bearing sediments during depressurization. However, water pressure recovery will lead to failure when the axial load is larger than the strength of the Methane Hydrate-bearing sediments after dissociation. (4) The depressurization rate shows little effect on the ultimate deformation of Methane Hydrate-bearing sediments, while the initial deformation rate increases with increasing depressurization rate. (5) The larger the reduction of pore pressure, the larger axial strain and volumetric strain.
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development of high pressure low temperature plane strain testing apparatus for Methane Hydrate bearing sand
Soils and Foundations, 2013Co-Authors: Jun Yoneda, M. Hyodo, Yukio Nakata, Norimasa Yoshimoto, Akira KatoAbstract:Abstract A high-pressure low-temperature plane strain testing apparatus was developed for visualizing the deformation of Methane Hydrate-bearing sand due to Methane Hydrate production. Using this testing apparatus, plane strain compression tests were performed on pure Toyoura sand and Methane Hydrate-bearing sand with localized deformation measurements. From the results, it was observed that the Methane Hydrate-free specimens, despite their relatively high density, showed changes in compressive volume. Marked increases in the initial stiffness and strength of the Methane Hydrate-bearing sand were observed (Methane Hydrate saturation of S MH =60%). Moreover, the volumetric strain changed from compressive to dilative. For the specimens with Methane Hydrate, a dilative behavior above S MH =0% was observed. An image analysis showed that the shear bands of the Methane Hydrate-bearing sand were thinner and steeper than those of the host sand. In addition, the dilative volumetric strain in the shear band increased markedly when Methane Hydrate existed in the pore spaces.
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Bonding Strength by Methane Hydrate Formed among Sand Particles
AIP Conference Proceedings, 2009Co-Authors: M. Hyodo, Yukio Nakata, Norimasa Yoshimoto, Rolando P. Orense, Jun YonedaAbstract:The mechanical properties of Methane Hydrate‐bearing sand were investigated by low temperature and high confining pressure triaxial testing apparatus in the present study. The specimens were prepared by infiltrating the Methane gas into partially saturated sand specimen under the given temperature and stress condition which is compatible with the phase equilibrium condition for the stability of Methane Hydrate. The tests were firstly performed to investigate the effect of temperature on the shear behaviour of the specimen. Then the effect of backpressure was investigated. The strength of Methane Hydrate bearing sand increased as the temperature decreased and the back pressure increased. The bonding strength due to Methane Hydrate was dependent on Methane Hydrate saturation, temperature and back pressure but independent of effective stress. Dissociation tests of Methane Hydrate were also performed by applying the temperature to the specimen at the various initial stress conditions. The marked development o...
Norimasa Yoshimoto - One of the best experts on this subject based on the ideXlab platform.
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effects of dissociation on the shear strength and deformation behavior of Methane Hydrate bearing sediments
Marine and Petroleum Geology, 2014Co-Authors: M. Hyodo, Yanghui Li, Yukio Nakata, Norimasa Yoshimoto, Jun Yoneda, Akira NishimuraAbstract:Abstract A series of tests were conducted in order to investigate the shear strength and deformation behavior of Methane Hydrate-bearing sediments during dissociation using the thermal recovery method or depressurization method. An innovative temperature-controlled high pressure triaxial apparatus which can reproduce the in situ conditions of Hydrate reservoirs was used. The results indicate that: (1) the failure strength of isotropically consolidated Methane Hydrate-bearing sediments which dissociated completely using the thermal recovery method is less than that of pure Toyoura sand. However, the initial stiffness and volumetric strain are higher than that of pure Toyoura sand. (2) The thermal recovery method will cause the failure of Methane Hydrate-bearing sediments when the axial load is higher than the strength of Methane Hydrate-bearing sediments after dissociation. (3) The depressurization method will not cause collapse of Methane Hydrate-bearing sediments during depressurization. However, water pressure recovery will lead to failure when the axial load is larger than the strength of the Methane Hydrate-bearing sediments after dissociation. (4) The depressurization rate shows little effect on the ultimate deformation of Methane Hydrate-bearing sediments, while the initial deformation rate increases with increasing depressurization rate. (5) The larger the reduction of pore pressure, the larger axial strain and volumetric strain.
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development of high pressure low temperature plane strain testing apparatus for Methane Hydrate bearing sand
Soils and Foundations, 2013Co-Authors: Jun Yoneda, M. Hyodo, Yukio Nakata, Norimasa Yoshimoto, Akira KatoAbstract:Abstract A high-pressure low-temperature plane strain testing apparatus was developed for visualizing the deformation of Methane Hydrate-bearing sand due to Methane Hydrate production. Using this testing apparatus, plane strain compression tests were performed on pure Toyoura sand and Methane Hydrate-bearing sand with localized deformation measurements. From the results, it was observed that the Methane Hydrate-free specimens, despite their relatively high density, showed changes in compressive volume. Marked increases in the initial stiffness and strength of the Methane Hydrate-bearing sand were observed (Methane Hydrate saturation of S MH =60%). Moreover, the volumetric strain changed from compressive to dilative. For the specimens with Methane Hydrate, a dilative behavior above S MH =0% was observed. An image analysis showed that the shear bands of the Methane Hydrate-bearing sand were thinner and steeper than those of the host sand. In addition, the dilative volumetric strain in the shear band increased markedly when Methane Hydrate existed in the pore spaces.
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Bonding Strength by Methane Hydrate Formed among Sand Particles
AIP Conference Proceedings, 2009Co-Authors: M. Hyodo, Yukio Nakata, Norimasa Yoshimoto, Rolando P. Orense, Jun YonedaAbstract:The mechanical properties of Methane Hydrate‐bearing sand were investigated by low temperature and high confining pressure triaxial testing apparatus in the present study. The specimens were prepared by infiltrating the Methane gas into partially saturated sand specimen under the given temperature and stress condition which is compatible with the phase equilibrium condition for the stability of Methane Hydrate. The tests were firstly performed to investigate the effect of temperature on the shear behaviour of the specimen. Then the effect of backpressure was investigated. The strength of Methane Hydrate bearing sand increased as the temperature decreased and the back pressure increased. The bonding strength due to Methane Hydrate was dependent on Methane Hydrate saturation, temperature and back pressure but independent of effective stress. Dissociation tests of Methane Hydrate were also performed by applying the temperature to the specimen at the various initial stress conditions. The marked development o...
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basic research on the mechanical behavior of Methane Hydrate sediments mixture
Soils and Foundations, 2005Co-Authors: M. Hyodo, Yukio Nakata, Norimasa Yoshimoto, Toshiro EbinumaAbstract:The possible existence of a vast amount of Methane Hydrate around islands has attracted attention as the largest potential hydrocarbon resource in Japan. At the same time, several production methods have been considered to extract the gas from the Hydrate zone. Although it is known that the Hydrates pose significant obstacles to drilling and production operations, there is at present only limited knowledge on the mechanical behavior of Hydrate-rich zones, which is necessary to understand the stability around the site. In order to know the properties of Methane Hydrate and/ or its sand mixtures, a series of tests was carried out on artificial Methane Hydrate-sand mixtures, using low temperature and a newly developed high confining pressure triaxial compression technique. The sediments used in the mixture were obtained from a 207.75 m sea bottom core from the Nankai Trough, located 1152.75 m below sea level. The specimens used were prepared by compressing a mixture of artificial Methane Hydrate and the sediments with a volume ratio of sediments to the whole of specimen. On the basis of these experimental results, the factors affecting mechanical properties of the Hydrate and sediment mixtures are discussed. It is very essential to collect more data on the properties of Methane Hydrate and/or sedimentation (soil) mixture to understand the stability of any attempt at Methane Hydrate production.
Yukio Nakata - One of the best experts on this subject based on the ideXlab platform.
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effects of dissociation on the shear strength and deformation behavior of Methane Hydrate bearing sediments
Marine and Petroleum Geology, 2014Co-Authors: M. Hyodo, Yanghui Li, Yukio Nakata, Norimasa Yoshimoto, Jun Yoneda, Akira NishimuraAbstract:Abstract A series of tests were conducted in order to investigate the shear strength and deformation behavior of Methane Hydrate-bearing sediments during dissociation using the thermal recovery method or depressurization method. An innovative temperature-controlled high pressure triaxial apparatus which can reproduce the in situ conditions of Hydrate reservoirs was used. The results indicate that: (1) the failure strength of isotropically consolidated Methane Hydrate-bearing sediments which dissociated completely using the thermal recovery method is less than that of pure Toyoura sand. However, the initial stiffness and volumetric strain are higher than that of pure Toyoura sand. (2) The thermal recovery method will cause the failure of Methane Hydrate-bearing sediments when the axial load is higher than the strength of Methane Hydrate-bearing sediments after dissociation. (3) The depressurization method will not cause collapse of Methane Hydrate-bearing sediments during depressurization. However, water pressure recovery will lead to failure when the axial load is larger than the strength of the Methane Hydrate-bearing sediments after dissociation. (4) The depressurization rate shows little effect on the ultimate deformation of Methane Hydrate-bearing sediments, while the initial deformation rate increases with increasing depressurization rate. (5) The larger the reduction of pore pressure, the larger axial strain and volumetric strain.
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development of high pressure low temperature plane strain testing apparatus for Methane Hydrate bearing sand
Soils and Foundations, 2013Co-Authors: Jun Yoneda, M. Hyodo, Yukio Nakata, Norimasa Yoshimoto, Akira KatoAbstract:Abstract A high-pressure low-temperature plane strain testing apparatus was developed for visualizing the deformation of Methane Hydrate-bearing sand due to Methane Hydrate production. Using this testing apparatus, plane strain compression tests were performed on pure Toyoura sand and Methane Hydrate-bearing sand with localized deformation measurements. From the results, it was observed that the Methane Hydrate-free specimens, despite their relatively high density, showed changes in compressive volume. Marked increases in the initial stiffness and strength of the Methane Hydrate-bearing sand were observed (Methane Hydrate saturation of S MH =60%). Moreover, the volumetric strain changed from compressive to dilative. For the specimens with Methane Hydrate, a dilative behavior above S MH =0% was observed. An image analysis showed that the shear bands of the Methane Hydrate-bearing sand were thinner and steeper than those of the host sand. In addition, the dilative volumetric strain in the shear band increased markedly when Methane Hydrate existed in the pore spaces.
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Bonding Strength by Methane Hydrate Formed among Sand Particles
AIP Conference Proceedings, 2009Co-Authors: M. Hyodo, Yukio Nakata, Norimasa Yoshimoto, Rolando P. Orense, Jun YonedaAbstract:The mechanical properties of Methane Hydrate‐bearing sand were investigated by low temperature and high confining pressure triaxial testing apparatus in the present study. The specimens were prepared by infiltrating the Methane gas into partially saturated sand specimen under the given temperature and stress condition which is compatible with the phase equilibrium condition for the stability of Methane Hydrate. The tests were firstly performed to investigate the effect of temperature on the shear behaviour of the specimen. Then the effect of backpressure was investigated. The strength of Methane Hydrate bearing sand increased as the temperature decreased and the back pressure increased. The bonding strength due to Methane Hydrate was dependent on Methane Hydrate saturation, temperature and back pressure but independent of effective stress. Dissociation tests of Methane Hydrate were also performed by applying the temperature to the specimen at the various initial stress conditions. The marked development o...
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basic research on the mechanical behavior of Methane Hydrate sediments mixture
Soils and Foundations, 2005Co-Authors: M. Hyodo, Yukio Nakata, Norimasa Yoshimoto, Toshiro EbinumaAbstract:The possible existence of a vast amount of Methane Hydrate around islands has attracted attention as the largest potential hydrocarbon resource in Japan. At the same time, several production methods have been considered to extract the gas from the Hydrate zone. Although it is known that the Hydrates pose significant obstacles to drilling and production operations, there is at present only limited knowledge on the mechanical behavior of Hydrate-rich zones, which is necessary to understand the stability around the site. In order to know the properties of Methane Hydrate and/ or its sand mixtures, a series of tests was carried out on artificial Methane Hydrate-sand mixtures, using low temperature and a newly developed high confining pressure triaxial compression technique. The sediments used in the mixture were obtained from a 207.75 m sea bottom core from the Nankai Trough, located 1152.75 m below sea level. The specimens used were prepared by compressing a mixture of artificial Methane Hydrate and the sediments with a volume ratio of sediments to the whole of specimen. On the basis of these experimental results, the factors affecting mechanical properties of the Hydrate and sediment mixtures are discussed. It is very essential to collect more data on the properties of Methane Hydrate and/or sedimentation (soil) mixture to understand the stability of any attempt at Methane Hydrate production.
Yanghui Li - One of the best experts on this subject based on the ideXlab platform.
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effects of dissociation on the shear strength and deformation behavior of Methane Hydrate bearing sediments
Marine and Petroleum Geology, 2014Co-Authors: M. Hyodo, Yanghui Li, Yukio Nakata, Norimasa Yoshimoto, Jun Yoneda, Akira NishimuraAbstract:Abstract A series of tests were conducted in order to investigate the shear strength and deformation behavior of Methane Hydrate-bearing sediments during dissociation using the thermal recovery method or depressurization method. An innovative temperature-controlled high pressure triaxial apparatus which can reproduce the in situ conditions of Hydrate reservoirs was used. The results indicate that: (1) the failure strength of isotropically consolidated Methane Hydrate-bearing sediments which dissociated completely using the thermal recovery method is less than that of pure Toyoura sand. However, the initial stiffness and volumetric strain are higher than that of pure Toyoura sand. (2) The thermal recovery method will cause the failure of Methane Hydrate-bearing sediments when the axial load is higher than the strength of Methane Hydrate-bearing sediments after dissociation. (3) The depressurization method will not cause collapse of Methane Hydrate-bearing sediments during depressurization. However, water pressure recovery will lead to failure when the axial load is larger than the strength of the Methane Hydrate-bearing sediments after dissociation. (4) The depressurization rate shows little effect on the ultimate deformation of Methane Hydrate-bearing sediments, while the initial deformation rate increases with increasing depressurization rate. (5) The larger the reduction of pore pressure, the larger axial strain and volumetric strain.
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Experimental Research on the Mechanical Properties of Methane Hydrate-Ice Mixtures
Energies, 2012Co-Authors: Yanghui Li, Yongchen Song, Feng YuAbstract:The mechanical properties of Methane Hydrate are important to the stability of borehole and Methane extraction from a Methane Hydrate reservoir. In this study, a series of triaxial compression tests were carried out on laboratory-formed Methane Hydrate-ice mixtures with various Methane Hydrate contents. Axial loading was conducted at an axial strain rate of 1.33%/min and a constant temperature of −10 °C. The results indicate that: (1) the deformation behavior is strongly affected by confining pressure and Methane Hydrate content; (2) the failure strength significantly increases with confining pressure when confining pressure is less than 10 MPa, and decreases with Methane Hydrate content; (3) the cohesion decreases with Methane Hydrate content, while the internal friction angle increases with Methane Hydrate content; (4) the strength of ice specimens are higher than that of Methane Hydrate-ice mixture specimens; Based on the experimental data, the relationship among failure strength, confining pressure and Methane Hydrate content was obtained, and a modified Mohr-Coulomb criterion considering the influence of Methane Hydrate content on shear strength was proposed
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Study on Shear Strength of Artificial Methane Hydrate
29th International Conference on Ocean Offshore and Arctic Engineering: Volume 4, 2010Co-Authors: Feng Yu, Yanghui Li, Yongchen Song, Jiafei ZhaoAbstract:The production of Methane from Hydrate reservoir may induce deformation of the Hydrate-bearing strata. The research on mechanical properties of Methane Hydrate and establishing an efficient Methane exploitation technology appear very important. In this paper, a low-temperature high-pressure triaxial test system including pressure crystal device (sample preparation system) was developed. A series of triaxial shear tests were carried out on artificial Methane Hydrate samples. The mechanical behavior was analyzed. The preliminary results show that the shear strength of Methane Hydrate increases with the increase of confining pressure and strain rate. While it increases with the decrease of temperature. Moreover, the secant modulus increases with the enhancement of strain rate and the decrease of confining pressure.Copyright © 2010 by ASME
William F Waite - One of the best experts on this subject based on the ideXlab platform.
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simultaneous determination of thermal conductivity thermal diffusivity and specific heat in si Methane Hydrate
Geophysical Journal International, 2007Co-Authors: William F Waite, Laura A. Stern, Stephen H. Kirby, William J Winters, David H MasonAbstract:SUMMARY Thermal conductivity, thermal diffusivity and specific heat of sI Methane Hydrate were measured as functions of temperature and pressure using a needle probe technique. The temperature dependence was measured between −20 ◦ C and 17 ◦ C at 31.5 MPa. The pressure dependence was measured between 31.5 and 102 MPa at 14.4 ◦ C. Only weak temperature and pressure dependencies were observed. Methane Hydrate thermal conductivity differs from that of water by less than 10 per cent, too little to provide a sensitive measure of Hydrate content in watersaturated systems. Thermal diffusivity of Methane Hydrate is more than twice that of water, however, and its specific heat is about half that of water. Thus, when drilling into or through Hydrate-rich sediment, heat from the borehole can raise the formation temperature more than 20 per cent faster than if the formation’s pore space contains only water. Thermal properties of Methane Hydrate should be considered in safety and economic assessments of Hydrate-bearing sediment.
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Methane Hydrate formation in partially water saturated ottawa sand
American Mineralogist, 2004Co-Authors: William F Waite, William J Winters, D H MasonAbstract:Bulk properties of gas Hydrate-bearing sediment strongly depend on whether Hydrate forms primarily in the pore fluid, becomes a load-bearing member of the sediment matrix, or cements sediment grains. Our compressional wave speed measurements through partially water-saturated, Methane Hydrate-bearing Ottawa sands suggest Hydrate surrounds and cements sediment grains. The three Ottawa sand packs tested in the Gas Hydrate And Sediment Test Laboratory Instrument (GHASTLI) contain 38(1)% porosity, initially with distilled water saturating 58, 31, and 16% of that pore space, respectively. From the volume of Methane gas produced during Hydrate dissociation, we calculated the Hydrate concentration in the pore space to be 70, 37, and 20% respectively. Based on these Hydrate concentrations and our measured compressional wave speeds, we used a rock physics model to differentiate between potential pore-space Hydrate distributions. Model results suggest Methane Hydrate cements unconsolidated sediment when forming in systems containing an abundant gas phase.