Influence of bedding structure on stress-induced elastic wave anisotropy in tight sandstones

doi:10.1016/j.jrmge.2020.06.003

	Influence of bedding structure on stress-induced elastic wave anisotropy in tight sandstones
	Li, Xiaying 3,4; Lei, Xinglin 1; Li, Qi 3,4; Chen, Dianguo 2
刊名	JOURNAL OF ROCK MECHANICS AND GEOTECHNICAL ENGINEERING
	2021-02-01
卷号	13 期号:1 页码:98-113
关键词	Elastic wave anisotropy Stress-induced anisotropy Anisotropy reversal Bedding orientation Microstructure Tight sandstone
ISSN号	1674-7755
DOI	10.1016/j.jrmge.2020.06.003
英文摘要	To understand the evolution of stress-induced elastic wave anisotropy, three triaxial experiments were performed on sandstone specimens with bedding orientations parallel, perpendicular, and oblique to the maximum principal stress. P-wave velocities along 64 different directions on each specimen were monitored frequently to understand the anisotropy change at various stress levels by fitting Thomsen's anisotropy equation. The results show that the elastic wave anisotropy is very sensitive to mechanical loading. Under hydrostatic loading, the magnitude of anisotropy is reduced in all three specimens. However, under deviatoric stress loading, the evolution of anisotropic characteristics (magnitude and orientation of the symmetry axis) is bedding orientation dependent. Anisotropy reversal occurs in specimens with bedding normal/oblique to the maximum principal stress. P-wave anisotropy epsilon' is linearly related to volumetric strain S-v and dilatancy, indicating that stress-induced redistribution of microcracks has a significant effect on P-wave velocity anisotropy. The closure of initial cracks and pores aligned in the bedding direction contributes to the decrease of the anisotropy. However, opening of new cracks, aligned in the maximum principal direction, accounts for the increase of the anisotropy. The experimental results provide some insights into the microstructural behavior under loading and provide an experimental basis for seismic data interpretation and parameter selection in engineering applications. (C) 2021 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Production and hosting by Elsevier B.V.
资助项目	National Natural Science Foundation of China[41902297] ; National Natural Science Foundation of China[41872210] ; Natural Science Foundation of Hubei Province[2018CFB292] ; Open Research Fund of State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences[Z017006]
WOS研究方向	Engineering
语种	英语
出版者	SCIENCE PRESS
WOS记录号	WOS:000625340800006
内容类型	期刊论文
源URL	[http://119.78.100.198/handle/2S6PX9GI/25897]
专题	中科院武汉岩土力学所
通讯作者	Li, Qi
作者单位	1.Natl Inst Adv Ind Sci & Technol, Tsukuba, Ibaraki 3058567, Japan 2.Chongqing Dizhiyuan Geol & Engn Testing Co Ltd, Chongqing 401329, Peoples R China 3.Univ Chinese Acad Sci, Beijing 100049, Peoples R China 4.Chinese Acad Sci, Inst Rock & Soil Mech, State Key Lab Geomech & Geotech Engn, Wuhan 430071, Peoples R China
推荐引用方式 GB/T 7714	Li, Xiaying,Lei, Xinglin,Li, Qi,et al. Influence of bedding structure on stress-induced elastic wave anisotropy in tight sandstones[J]. JOURNAL OF ROCK MECHANICS AND GEOTECHNICAL ENGINEERING,2021,13(1):98-113.
APA	Li, Xiaying,Lei, Xinglin,Li, Qi,&Chen, Dianguo.(2021).Influence of bedding structure on stress-induced elastic wave anisotropy in tight sandstones.JOURNAL OF ROCK MECHANICS AND GEOTECHNICAL ENGINEERING,13(1),98-113.
MLA	Li, Xiaying,et al."Influence of bedding structure on stress-induced elastic wave anisotropy in tight sandstones".JOURNAL OF ROCK MECHANICS AND GEOTECHNICAL ENGINEERING 13.1(2021):98-113.