Mechanism of soil stratum instability induced by hydrate dissociation

OCEAN ENGINEERING

卷:122

Article

Zhang, X. H.¹  Lu, X. B.¹  Chen, X. D.¹  Zhang, L. M.²  Shi, Y. H.³ 

[1] Chinese Acad Sci, Inst Mech, Beijing, Peoples R China

[2] Hong Kong Univ Sci & Technol, Hong Kong, Hong Kong, Peoples R China

[3] Guangzhou Marine Geol Survey, Guangzhou 510075, Guangdong, Peoples R China

关键词: Hydrate dissociation;    Centrifugal test;    Heat transfer;    Slope stability;    Fractures;   

DOI  :  10.1016/j.oceaneng.2016.06.015

来源: Elsevier

【 摘 要 】

Gas hydrate dissociation may lead to soil stratum instability such as marine landslides in hydrate-bearing sediments. In this paper, centrifugal tests were conducted to investigate the soil responses and stratum instability of a 14 degrees slope during hydrate dissociation under centrifugal accelerations of 50g and 100g, different boundary conditions and heating modes. New phenomena such as sliding of the over layer, layered fractures between the hydrate layer and the over layer, and fractures in the over layer were observed. The fluid pressures, horizontal displacements and vertical displacements of the soils were measured and compared under different conditions. The observed mechanisms and decoupled formulations considering heat transfer, fluid seepage, soil deformation and critical soil failure were presented and discussed. The formation of layered fractures during hydrate dissociation is regarded as an important factor leading to the instability of the slope. (C) 2016 Elsevier Ltd. All rights reserved.

【 授权许可】

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