Fracture Roughness and Correlation Length in the Central Force Model

Jan Øystein Haavig Bakke; Thomas Ramstad; Alex Hansen

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Fracture Roughness and Correlation Length in the Central Force Model

Jan Øystein Haavig Bakke·Thomas Ramstad·Alex Hansen

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Abstract

We measure the roughness exponent and the correlation length exponent of a stress-weighted percolation process in the central force model in 2D. The roughness exponent is found to be zeta = 0.75 \pm 0.03 and the correlation length exponent is found to be nu = 1.7 \pm 0.3. This result supports a conjecture that the fracture roughness for large scales is controlled by a stress weighted percolation process, and the fracture roughness can by calculated from the correlation length exponent by zeta = 2*nu/(1+2*nu). We also compare global and local measurements of the fracture roughness and do not find sign of anomalous scaling in the central force model.

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Jan Øystein Haavig Bakke, Thomas Ramstad, Alex Hansen. 2005-07-26. Fracture Roughness and Correlation Length in the Central Force Model. https://arxiv.org/abs/cond-mat/0507611

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