Methane hydrate was found interbedded with clayey sediments in permafrost regions, and it is important to study the mechanical properties of the hydrate-bearing layers to assess the stability during hydrate exploitation. In this paper, a series of triaxial experiments was conducted on hydrate-bearing sediments which were prepared by compacting hydrate layer (A), kaolin clay layer (B) and the mixture of hydrate and kaolin clay layer (C) in different orders (ABC, ACB, CAB) and with different tilted angles (0°, 10°, 25°) in a specially designed mold device. The volume of methane hydrate was 40% of the whole volume of the sample. The triaxial experiments were conducted under the confining pressure of 5MPa, temperature of -10℃ and strain rate of 1%/min. The results indicated that the maximum deviator stress of the sediments (ABC) increased with the increasing of the tilted angle of layers, however, there was an opposite trend with the sediments (CAB). And the maximum deviator stress of the sediments (ACB) increased first and then decreased. The failure strength achieved maximum when the hydrate layer was in the center of the sediments.
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