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DOI	10.1029/2019JB018970
	Sliding Crack Model for Nonlinearity and Hysteresis in the Triaxial Stress-Strain Curve of Rock, and Application to Antigorite Deformation
	David E.C.; Brantut N.; Hirth G.
发表日期	2020
ISSN	21699313
卷号	125 期号:10
英文摘要	Under triaxial deviatoric loading at stresses below failure, rocks generally exhibit nonlinearity and hysteresis in the stress-strain curve. In 1965, Walsh first explained this behavior in terms of frictional sliding along the faces of closed microcracks. The hypothesis is that crack sliding is the dominant mode of rock inelasticity at moderate compressive stresses for certain rock types. Here we extend the model of David et al. (2012, https://doi.org/10.1016/j.ijrmms.2012.02.001) to include (i) the effect of the confining stress; (ii) multiple load-unload cycles; (iii) calculation of the dissipated strain energy upon unload-reload; (iv) either frictional or cohesive behavior; and (v) either aligned or randomly oriented cracks. Closed-form expressions are obtained for the effective Young's modulus during loading, unloading, and reloading, as functions of the mineral's Young's modulus, the crack density, the crack friction coefficient and cohesion for the frictional and cohesive sliding models, respectively, and the crack orientation in the case of aligned cracks. The dissipated energy per cycle is quadratic and linear in stress for the frictional and cohesive models, respectively. Both models provide a good fit to a cyclic loading data set on polycrystalline antigorite, based on a compilation of literature and newly acquired data, at various pressures and temperatures. At high pressure, with increasing temperature, the model results reveal a decrease in friction coefficient and a transition from a frictionally to a cohesively controlled behavior. New measurements of fracture toughness and tensile strength provide quantitative support that inelastic behavior in antigorite is predominantly caused by shear crack sliding and propagation without dilatancy. ©2020. The Authors.
英文关键词	antigorite serpentinite; brittle-plastic transition; cyclic loading; frictional/cohesive crack sliding; rock inelasticity; triaxial stress-strain
语种	英语
来源期刊	Journal of Geophysical Research: Solid Earth
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/187533
作者单位	Department of Earth Sciences, University College London, London, United Kingdom; Department of Earth, Environmental and Planetary Sciences, Brown University, Providence, RI, United States
推荐引用方式 GB/T 7714	David E.C.,Brantut N.,Hirth G.. Sliding Crack Model for Nonlinearity and Hysteresis in the Triaxial Stress-Strain Curve of Rock, and Application to Antigorite Deformation[J],2020,125(10).
APA	David E.C.,Brantut N.,&Hirth G..(2020).Sliding Crack Model for Nonlinearity and Hysteresis in the Triaxial Stress-Strain Curve of Rock, and Application to Antigorite Deformation.Journal of Geophysical Research: Solid Earth,125(10).
MLA	David E.C.,et al."Sliding Crack Model for Nonlinearity and Hysteresis in the Triaxial Stress-Strain Curve of Rock, and Application to Antigorite Deformation".Journal of Geophysical Research: Solid Earth 125.10(2020).