A cohesionless micromechanical model for gas hydrate bearing sediments

E. Cohen, A. Klar*

*Corresponding author for this work

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

A proper representation and understanding of the mechanical response of the sediment is a prerequisite for successful future gas production from gas hydrate bearing sediments, in view of the geotechnical issues encountered in recent field trials. Recent investigations have indicated that the increase of sediment strength, due to hydrate existence, is of frictional nature and associated with changes in the kinematic response, and not necessarily due to cementation. Following this idea, this paper presents a non-cohesive micro model for methane-hydrate bearing sediments, where the hydrate is represented as solid particles precisely positioned between sand particles, contributing
to the skeleton response even for small strains. Analytical expressions relating between the geometry, interparticle properties, and the mechanical response of the hydrate bearing sediment are developed in the paper. Global stress strain response is evaluated under simulated triaxial loading, exhibiting stiffer, stronger and more dilative response compared to pure sand samples. It is shown that a trade-off exists between the particle size and the inter-particle friction, which can be unifed using a participation factor related to the pore size distribution. As observed in recent experimental investigations, the suggested model results in a cohesionless response when analyzed using Rowe's stress dilatancy theory.
Original languageEnglish
JournalGranular Matter
Volume21
Issue number36
ISSN1434-5021
DOIs
Publication statusPublished - 2019

Keywords

  • Gas hydrate bearing sediments
  • Discrete element method
  • Strength
  • Stress dilatancy theory
  • Triaxial test

Cite this

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title = "A cohesionless micromechanical model for gas hydrate bearing sediments",
abstract = "A proper representation and understanding of the mechanical response of the sediment is a prerequisite for successful future gas production from gas hydrate bearing sediments, in view of the geotechnical issues encountered in recent field trials. Recent investigations have indicated that the increase of sediment strength, due to hydrate existence, is of frictional nature and associated with changes in the kinematic response, and not necessarily due to cementation. Following this idea, this paper presents a non-cohesive micro model for methane-hydrate bearing sediments, where the hydrate is represented as solid particles precisely positioned between sand particles, contributingto the skeleton response even for small strains. Analytical expressions relating between the geometry, interparticle properties, and the mechanical response of the hydrate bearing sediment are developed in the paper. Global stress strain response is evaluated under simulated triaxial loading, exhibiting stiffer, stronger and more dilative response compared to pure sand samples. It is shown that a trade-off exists between the particle size and the inter-particle friction, which can be unifed using a participation factor related to the pore size distribution. As observed in recent experimental investigations, the suggested model results in a cohesionless response when analyzed using Rowe's stress dilatancy theory.",
keywords = "Gas hydrate bearing sediments, Discrete element method, Strength, Stress dilatancy theory, Triaxial test",
author = "E. Cohen and A. Klar",
year = "2019",
doi = "10.1007/s10035-019-0887-5",
language = "English",
volume = "21",
journal = "Granular Matter",
issn = "1434-5021",
publisher = "Springer",
number = "36",

}

A cohesionless micromechanical model for gas hydrate bearing sediments. / Cohen, E.; Klar, A.

In: Granular Matter, Vol. 21, No. 36, 2019.

Research output: Contribution to journalJournal articleResearchpeer-review

TY - JOUR

T1 - A cohesionless micromechanical model for gas hydrate bearing sediments

AU - Cohen, E.

AU - Klar, A.

PY - 2019

Y1 - 2019

N2 - A proper representation and understanding of the mechanical response of the sediment is a prerequisite for successful future gas production from gas hydrate bearing sediments, in view of the geotechnical issues encountered in recent field trials. Recent investigations have indicated that the increase of sediment strength, due to hydrate existence, is of frictional nature and associated with changes in the kinematic response, and not necessarily due to cementation. Following this idea, this paper presents a non-cohesive micro model for methane-hydrate bearing sediments, where the hydrate is represented as solid particles precisely positioned between sand particles, contributingto the skeleton response even for small strains. Analytical expressions relating between the geometry, interparticle properties, and the mechanical response of the hydrate bearing sediment are developed in the paper. Global stress strain response is evaluated under simulated triaxial loading, exhibiting stiffer, stronger and more dilative response compared to pure sand samples. It is shown that a trade-off exists between the particle size and the inter-particle friction, which can be unifed using a participation factor related to the pore size distribution. As observed in recent experimental investigations, the suggested model results in a cohesionless response when analyzed using Rowe's stress dilatancy theory.

AB - A proper representation and understanding of the mechanical response of the sediment is a prerequisite for successful future gas production from gas hydrate bearing sediments, in view of the geotechnical issues encountered in recent field trials. Recent investigations have indicated that the increase of sediment strength, due to hydrate existence, is of frictional nature and associated with changes in the kinematic response, and not necessarily due to cementation. Following this idea, this paper presents a non-cohesive micro model for methane-hydrate bearing sediments, where the hydrate is represented as solid particles precisely positioned between sand particles, contributingto the skeleton response even for small strains. Analytical expressions relating between the geometry, interparticle properties, and the mechanical response of the hydrate bearing sediment are developed in the paper. Global stress strain response is evaluated under simulated triaxial loading, exhibiting stiffer, stronger and more dilative response compared to pure sand samples. It is shown that a trade-off exists between the particle size and the inter-particle friction, which can be unifed using a participation factor related to the pore size distribution. As observed in recent experimental investigations, the suggested model results in a cohesionless response when analyzed using Rowe's stress dilatancy theory.

KW - Gas hydrate bearing sediments

KW - Discrete element method

KW - Strength

KW - Stress dilatancy theory

KW - Triaxial test

U2 - 10.1007/s10035-019-0887-5

DO - 10.1007/s10035-019-0887-5

M3 - Journal article

VL - 21

JO - Granular Matter

JF - Granular Matter

SN - 1434-5021

IS - 36

ER -