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Summary: Research has shown that in fine-grained sediments in the South China Sea, the failure strength of methane hydrate-bearing sediments increases with the increase in hydrate saturation and initial effective mean stress. Additionally, the excess pore-water pressure of methane hydrate-bearing sediments remains positive during shear. It is observed that as the hydrate saturation increases, cohesion in the Mohr-Coulomb model increases while the internal friction angle has little dependence on the hydrate saturation.
CANADIAN GEOTECHNICAL JOURNAL
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Yanghui Li et al.
Summary: Methane hydrate is being widely considered as an energy source due to its environmentally friendly nature and large reserves, but it may induce geological disasters during the exploitation process, so it is necessary to comprehensively study its mechanical characteristics before commencing commercial development. The study found that under different effective confining pressures, there were differences in the results of multistage and single-stage triaxial loading tests, and the elastic modulus obtained also varied.
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Shi Shen et al.
Summary: Experimental data from mechanical experiments on HBSs at different temperatures and effective confining pressures revealed a significant correlation between the samples' mechanical properties and temperature and effective confining pressure. The strength of HBSs was found to be positively correlated with effective confining pressure and negatively correlated with temperature. Furthermore, the stress-strain behaviors of the samples shifted from hardening to softening with decreasing effective confining pressure and temperature.
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