Tri-Axial Shear Tests on Hydrate-Bearing Sediments during Hydrate Dissociation with Depressurization

A series of tri-axial shear tests were carried out to determine the stress and strain characteristics, as well as the volume deformation of methane hydrate-bearing sediments during gas hydrate dissociation. An innovative type of depressurization was adopted with a high-pressure and low-temperature t...

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Bibliographic Details
Published in:Energies
Main Authors: Li, Dongliang, Wu, Qi, Wang, Zhe, Lu, Jingsheng, Liang, Deqing, Li, Xiaosen
Format: Report
Language:English
Published: MDPI 2018
Subjects:
Online Access:http://ir.giec.ac.cn/handle/344007/23875
http://ir.giec.ac.cn/handle/344007/23876
https://doi.org/10.3390/en11071819
Description
Summary:A series of tri-axial shear tests were carried out to determine the stress and strain characteristics, as well as the volume deformation of methane hydrate-bearing sediments during gas hydrate dissociation. An innovative type of depressurization was adopted with a high-pressure and low-temperature tri-axial apparatus. Results show that: (1) decrease in pore pressure during the shear process may result in the failure of hydrate-bearing sediments, but they did not collapse completely due to high effective confining pressure; (2) depressurization leads to the contraction of volumetric strain and the ultimate deformation shows no difference compared to that prior depressurization; (3) high saturation hydrate-bearing sediments were more sensitive to depressurization, which could be due to the methane hydrate acting as a skeleton structure at some sites when the pore hydrates' saturation is high.