Factors Controlling the Difference in Brazilian and Direct Tensile Strengths of the Lac du Bonnet Granite

doi:10.1007/s00603-019-01946-x

	Factors Controlling the Difference in Brazilian and Direct Tensile Strengths of the Lac du Bonnet Granite
	Qi, Shengwen 1,3,4,5; Lan, Hengxing 2,3; Martin, Derek 3; Huang, Xiaolin 1,4,5
刊名	ROCK MECHANICS AND ROCK ENGINEERING
	2020-03-01
卷号	53 期号:3 页码:1005-1019
关键词	Brazilian tension strength Direct tension strength Grain-based model UDEC Ratio of the shear to normal stiffness Lac du Bonnet granite
ISSN号	0723-2632
DOI	10.1007/s00603-019-01946-x
通讯作者	Qi, Shengwen(qishengwen@mail.iggcas.ac.cn)
英文摘要	Laboratory tests showed that the average direct tension strength (DTS0) of the Lac du Bonnet granite was 6.9 MPa, and significantly less than its average Brazilian tension strength (BTS0), i.e., 8.8 MPa. In this paper, a grain-based model (GBM) with a 2D universal discrete element code (UDEC) was used to explore factors that could control the difference in the direct tension strength (DTS) and Brazilian tension strength (BTS) of the Lac du Bonnet granite from the micromechanical point of view. Micro parameters of the grain contacts were investigated, i.e., the tensile strength (T), cohesion (c), friction angle (phi), and the ratio of the shear to normal stiffness (lambda). Results show that both BTS and DTS highly depended on log(lambda). With an increase in log(lambda), the BTS first increased nonlinearly and decreased instead after achieving a peak while the DTS always increased nonlinearly. The BTS was sensitive to T and c, while the DTS was mainly sensitive to T. The ratio of DTS to BTS first decreased with the increase of log(lambda) and then increased instead from a minimum. It was found that the GBM with UDEC can well reproduce the uniaxial compression, direct tension and Brazilian tests of the Lac du Bonnet granite simultaneously only on condition that lambda = 2.51. This indicated that the shear stiffness of the grain boundary in the Lac du Bonnet granite may be several times larger than its normal stiffness. This may be the main factor controlling the difference in the BTS and DTS of the Lac du Bonnet granite.
WOS关键词	PARTICLE MODEL ; ROCK-MECHANICS ; FAILURE ; MICROSTRUCTURE ; COMPRESSION ; FRACTURE ; TESTS
WOS研究方向	Engineering ; Geology
语种	英语
出版者	SPRINGER WIEN
WOS记录号	WOS:000522733700003
内容类型	期刊论文
源URL	[http://ir.igsnrr.ac.cn/handle/311030/133486]
专题	中国科学院地理科学与资源研究所
通讯作者	Qi, Shengwen
作者单位	1.Chinese Acad Sci, Inst Geol & Geophys, Key Lab Shale Gas & Geoengn, Beijing, Peoples R China 2.Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, State Key Lab Resources & Environm Informat Syst, Beijing, Peoples R China 3.Univ Alberta, Dept Civil & Environm Engn, Edmonton, AB, Canada 4.Univ Chinese Acad Sci, Beijing, Peoples R China 5.Chinese Acad Sci, Inst Earth Sci, Beijing, Peoples R China
推荐引用方式 GB/T 7714	Qi, Shengwen,Lan, Hengxing,Martin, Derek,et al. Factors Controlling the Difference in Brazilian and Direct Tensile Strengths of the Lac du Bonnet Granite[J]. ROCK MECHANICS AND ROCK ENGINEERING,2020,53(3):1005-1019.
APA	Qi, Shengwen,Lan, Hengxing,Martin, Derek,&Huang, Xiaolin.(2020).Factors Controlling the Difference in Brazilian and Direct Tensile Strengths of the Lac du Bonnet Granite.ROCK MECHANICS AND ROCK ENGINEERING,53(3),1005-1019.
MLA	Qi, Shengwen,et al."Factors Controlling the Difference in Brazilian and Direct Tensile Strengths of the Lac du Bonnet Granite".ROCK MECHANICS AND ROCK ENGINEERING 53.3(2020):1005-1019.