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A damage-mechanics model for fracture nucleation and propagation

Department of Physics, One Shields Ave., University of California, Davis, CA 95616, United States; Department of Geology, One Shields Ave., University of California, Davis, CA 95616, United States; Sante Fe Institute, Santa Fe, NM 87501, United States; Department of Physics, Boston University, Boston, MA 02215, United States
Theoretical and Applied Fracture Mechanics (Impact Factor: 0.63). 06/2010; DOI: 10.1016/j.tafmec.2010.06.002

ABSTRACT In this paper, a composite model for earthquake rupture initiation and propagation is proposed. The model includes aspects of damage mechanics, fiber-bundle models, and slider-block models. An array of elements is introduced in analogy to the fibers of a fiber bundle. Time to failure for each element is specified from a Poisson distribution. The hazard rate is assumed to have a power-law dependence on stress. When an element fails it is removed, the stress on a failed element is redistributed uniformly to a specified number of neighboring elements in a given range of interaction. Damage is defined to be the fraction of elements that have failed. Time to failure and modes of rupture propagation are determined as a function of the hazard-rate exponent and the range of interaction.

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