Geomechanical Constitutive Modelling of Gas-hydrate- Bearing Sediments

نویسندگان

  • Nabil Sultan
  • Sébastien Garziglia
چکیده

In this work and in order to consider theoretically the effect of gas hydrates on the mechanical properties of their host sediments, hydrate fraction was introduced as a state variable in the framework of a Critical State model. For the proposed model, the process of de-structuration and softening of natural clay was considered as a proxy for the gas-hydrate-bearing-sediments behaviour. The developed constitutive model seemed to reproduce the main key behaviours of gas-hydrate-bearing sands observed by Masui and co-authors: i) the elastic properties (Young Modulus, shear modulus) and the strength of the sediment-hydrate medium increase with the hydrate fraction ii) the mechanical softening of the gas-hydrate bearing sediment is amplified with the hydrate fraction and iii) the dilation angle increases with the hydrate fraction.

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" This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implies, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or rep...

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تاریخ انتشار 2011