Transgranular fracturing of crystalline rocks and its influence on rock strengths: Insights from a grain-scale continuum-discontinuum approach

doi:10.1016/j.cma.2020.113462

	Transgranular fracturing of crystalline rocks and its influence on rock strengths: Insights from a grain-scale continuum-discontinuum approach
	Li, X. F.1,2,3; Li, H. B.1,2; Zhao, J.3
刊名	COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
	2021
卷号	373 页码:31
关键词	Inter/transgranular fracturing Heterogeneity Multiscale grain-based model Hybrid continuum-discontinuum Rocks
ISSN号	0045-7825
DOI	10.1016/j.cma.2020.113462
英文摘要	The aim of this study is to understand the effects of micro-heterogeneity, such as grain size, morphology and mineralogy, on the initiation, propagation and coalescence of microcracks in heterogeneous materials. A multiscale grain-breakable continuum-discontinuum model incorporating realistic micro-heterogeneity reproduction method is proposed to investigate the fracturing behaviours and confinement mechanism of rocks. Crack initiation and damage stresses are intrinsic properties of rocks determined by grain-scale heterogeneity. Intergranular tensile cracks are primarily initiated as a result of local stress heterogeneity along grain boundaries. The subsequent generation of transgranular shear cracks implies a rapid proliferation of grain-crossing fractures, leads to large-scale crack interaction and coalescence. The effect of confinement inhibits crack extension and increases the appearance of shear-induced grain pulverizations. Furthermore, the effects of grain size, grain morphology and mineralogy on macro mechanical properties, including crack initiation stress, crack damage stress, uniaxial compression strength and elastic modulus, are discussed. The simulated results indicate that the larger grain size contributes to stronger local stress heterogeneity, which results in a lower failure strength of rocks. The crack initiation stress is determined by local heterogeneity and is less affected by the change in average grain size. Grain morphology plays an important role in grain interlocking while a reduction in grain size variance leads to a more homogeneous stress field. The mineralogy is evaluated with the aid of a quartz-mica-feldspar diagram, and the quantitative relationships between mineralogy and the macro-scale mechanical properties of rocks are discussed. (C) 2020 Elsevier B.V. All rights reserved.
资助项目	National Natural Science Foundation of China (NSFC)[51439008] ; National Natural Science Foundation of China (NSFC)[51679231] ; China Scholarship Council[201604910678]
WOS研究方向	Engineering ; Mathematics ; Mechanics
语种	英语
出版者	ELSEVIER SCIENCE SA
WOS记录号	WOS:000601037900009
内容类型	期刊论文
源URL	[http://119.78.100.198/handle/2S6PX9GI/25395]
专题	中科院武汉岩土力学所
通讯作者	Li, H. B.
作者单位	1.Chinese Acad Sci, Inst Rock & Soil Mech, State Key Lab Geomech & Geotech Engn, Wuhan 430071, Peoples R China 2.Univ Chinese Acad Sci, Beijing 10049, Peoples R China 3.Monash Univ, Dept Civil Engn, Clayton, Vic 3800, Australia
推荐引用方式 GB/T 7714	Li, X. F.,Li, H. B.,Zhao, J.. Transgranular fracturing of crystalline rocks and its influence on rock strengths: Insights from a grain-scale continuum-discontinuum approach[J]. COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING,2021,373:31.
APA	Li, X. F.,Li, H. B.,&Zhao, J..(2021).Transgranular fracturing of crystalline rocks and its influence on rock strengths: Insights from a grain-scale continuum-discontinuum approach.COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING,373,31.
MLA	Li, X. F.,et al."Transgranular fracturing of crystalline rocks and its influence on rock strengths: Insights from a grain-scale continuum-discontinuum approach".COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING 373(2021):31.