Natural gas hydrate has the advantages of large reserves, wide distribution and clean combustion. In recent years, it has attracted a wide spread attention. In order to realize the safe and efficient exploitation of natural gas hydrate, it is necessary to systematically evaluate the mechanical stability of hydrate-bearing sediments. In this paper, the methane hydrate-bearing sediments with 40% porosity were remoulded firstly, and based on the laboratory equipment for mechanics experiments, under the conditions of different confining pressures, a series of triaxial compression tests were performed. The strength and deformation characteristics of the sediments during hydrate dissociation were obtained, and the corresponding stress-strain curves were drawn. The results showed that the decomposition of natural gas hydrate can lead to the reduction of the sediments strength. In addition, based on the experimental data and the Duncan-Chang constitutive model, considering the influence of confining pressure and the dissociation time, a constitutive model of the sediment samples in the process of decomposition was constructed. This model could well simulate the stress-strain relationship of the sediments during the hydrate dissociation, providing the theoretical references to evaluate the stability of gas hydrate reservoirs.
ZHU Yi-ming
,
CHEN Chen
,
CHEN Zhong-yong
,
ZHOU Shu-yang
. A Constitutive Model of Hydrate-Bearing Sediments Considering the Hydrate Dissociation[J]. Advances in New and Renewable Energy, 2019
, 7(5)
: 385
-392
.
DOI: 10.3969/j.issn.2095-560X.2019.05.001
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