A Model for the Elastic Modulus of Hydrate-Bearing Sediments
- Xuhui Zhang (Chinese Academy of Sciences) | Lele Liu (Qingdao Institute of Marine Geology) | Junbing Zhou (Chinese Academy of Sciences) | Xiaobing Lu (Chinese Academy of Sciences) | Shuyun Wang (Chinese Academy of Sciences) | Changling Liu (Qingdao Institute of Marine Geology) | Yuguang Ye (Qingdao Institute of Marine Geology)
- Document ID
- International Society of Offshore and Polar Engineers
- International Journal of Offshore and Polar Engineering
- Publication Date
- December 2015
- Document Type
- Journal Paper
- 314 - 319
- 2015. The International Society of Offshore and Polar Engineers
- hydrate saturation, series and parallel model, elastic modulus, Hydrate-bearing sediment, hydrate occurrence
- 0 in the last 30 days
- 160 since 2007
- Show more detail
A model for the elastic modulus of hydrate-bearing sediment (HBS) is presented considering the variation of the hydrate saturation and hydrate occurrence mode. The model is based on the classical series and parallel modes, introducing a parameter of statistical force transfer paths among particles in HBS. Macro-triaxial compression tests and micro X-ray computed tomography (CT) observations of HBS in the gas-saturated formation mode were conducted. The applicability of the model was checked through the comparison between tests and theoretical results.
Natural gas hydrate, a compound of methane molecules and water molecules, extensively exists in marine and permafrost sediments. Hydrate-bearing sediment (HBS) is a new kind of multiphase composite geotechnical material that consists of the gas hydrate, soil skeleton, and pore fluid of gas and water. The mechanical properties of HBS are the basic parameters for the analysis of soil deformation and failures during hydrate exploration and exploitation.
Many studies have been conducted in the laboratory by triaxial compression tests to obtain the mechanical data of HBS (Masui et al., 2008; Hyodo et al., 2007; Hyodo, 2013; Miyazaki et al., 2010; Miyazaki and Masui, 2011; Waite et al., 2008, 2009; Winters, 1999; Winters et al., 2004; Yun et al., 2007; Zhang et al., 2012a; Song et al., 2010). Different methodologies for sampling methane hydrate (dissolved gas method, partial water saturation method, ice-seeding method, hydrate premixing method) resulted in different hydrate occurrence modes in the pores of sediment (Ecker et al., 2000; Winters et al., 2004). By the most adopted dissolved gas method, heterogeneous nucleation occurs on the particle surface, subsequently grows into the pore space (pore-filling type), and goes to the final cementation with grains (grain-cementation type). The most pronounced increase in strength occurs when the hydrate saturation exceeds 40%. The explanation is that once hydrate saturation exceeds the critical value, the hydrate occurrence mode transfers from the pore-filling type to the grain-cementation type.
|File Size||1 MB||Number of Pages||6|