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DOI	10.1007/s00603-022-02830-x
	Fracture Mechanical Properties of Frozen Sandstone at Different Initial Saturation Degrees
	Wang, Ting; Sun, Qiang; Jia, Hailiang; Shen, Yanjun; Li, Guoyu
通讯作者	Jia, HL (通讯作者)，Xian Univ Sci & Technol, Coll Architecture & Civil Engn, 58 Yanta Middle Rd, Xian 710054, Shaanxi, Peoples R China.
发表日期	2020
ISSN	0723-2632
EISSN	1434-453X
英文摘要	The fracture mechanics of frozen rock are important to engineering in cold regions, yet the basic properties and influences remain unclear. The fracture toughness of semi-circular bend (SCB) samples with different initial saturation degrees (ISDs) was tested at - 20 celcius. Acoustic emission (AE) and digital image correlation (DIC) systems were used to capture AE signals and surface deformation under load testing. In addition, the phase composition in rock pores was measured by low-field nuclear magnetic resonance (LF-NMR). It was found that: (1) Fracturing of frozen sandstone generally consists of three stages: pore or microcrack closing, elastic deformation and microcrack propagation which is evidenced by the variation of AE counts and the maximum horizontal strain within the fracture process zone (FPZ) under loading. (2) The ISD has a great influence on fracture toughness and the microcrack propagation process. With increases in ISD, both the fracture toughness and fracture energy of frozen sandstone varies in a mode of slow increase (ISD < 40%), rapid increase (ISD 40-90%) and slight decrease (ISD 90-100%). (3) The phase composition in pores of frozen rock with low ISD (< 40%) is significantly different from that with high ISD (40-100%). At ISDs of < 40%, the ice in rock pores mainly originates from adsorbed water; however, at ISDs of 40-100%, the ice increasingly comes from free and capillary water. Based on the test results, the difference in fracture mechanical properties of frozen sandstone introduced by different ISDs can be attributed to the changes in pore phase composition, which determines the interaction between pore ice/unfrozen water and rock skeleton involving three processes: strengthening due to the filling effect of pore ice, strengthening due to the adhesion force and tensile strength of pore ice, and weakening due to frost damage.
关键词	PROCESS ZONE WATER-CONTENT TOUGHNESS ICE ADHESION NMR
英文关键词	Frozen sandstone; Fracture toughness; Microcrack propagation process; Different initial saturation degree; Phase composition in pores
语种	英语
WOS研究方向	Engineering ; Geology
WOS类目	Engineering, Geological ; Geosciences, Multidisciplinary
WOS记录号	WOS:000766424400002
来源期刊	ROCK MECHANICS AND ROCK ENGINEERING
来源机构	中国科学院西北生态环境资源研究院
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/254413
作者单位	[Wang, Ting; Sun, Qiang; Shen, Yanjun] Xian Univ Sci & Technol, Coll Geol & Environm, Xian 710054, Shaanxi, Peoples R China; [Jia, Hailiang] Xian Univ Sci & Technol, Coll Architecture & Civil Engn, 58 Yanta Middle Rd, Xian 710054, Shaanxi, Peoples R China; [Li, Guoyu] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Frozen Soil Engn, Lanzhou, Peoples R China
推荐引用方式 GB/T 7714	Wang, Ting,Sun, Qiang,Jia, Hailiang,et al. Fracture Mechanical Properties of Frozen Sandstone at Different Initial Saturation Degrees[J]. 中国科学院西北生态环境资源研究院,2020.
APA	Wang, Ting,Sun, Qiang,Jia, Hailiang,Shen, Yanjun,&Li, Guoyu.(2020).Fracture Mechanical Properties of Frozen Sandstone at Different Initial Saturation Degrees.ROCK MECHANICS AND ROCK ENGINEERING.
MLA	Wang, Ting,et al."Fracture Mechanical Properties of Frozen Sandstone at Different Initial Saturation Degrees".ROCK MECHANICS AND ROCK ENGINEERING (2020).