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| Titel |
Temporal and spatial evolution of crackling bursts in a fiber bundle model |
| VerfasserIn |
Ferenc Kun, Zsuzsa Danku |
| Konferenz |
EGU General Assembly 2014
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 16 (2014) |
| Datensatznummer |
250091047
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| Publikation (Nr.) |
 EGU/EGU2014-6716.pdf |
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| Zusammenfassung |
| The fracture of heterogeneous materials proceeds in bursts which can be recorded by
acoustic or electromagnetic techniques. Although crackling noise is the major source
of information about the microscopic dynamics of fracture, its analysis mainly
focuses on the statistics of crackling events considering fracture as a stochastic
point-process.
Here we investigate the temporal and spacial evolution of single bursts emerging in
heterogeneous materials under a constant external load. Based on a fiber bundle
model we demonstrate that the average temporal shape of burst pulses encodes
information about the range of load redistribution following failure events: when the load
redistribution is localized along a propagating crack front the average temporal shape of
pulses has a right handed asymmetry due to the gradual acceleration of bursts. For
long range interaction, however, a symmetric shape with parabolic functional form
is obtained. The degree of asymmetry is found to depend on the pulse duration
revealing a load dependent characteristic time scale of the avalanche dynamics of
fracture.
In spite of the compact internal structure, the external frontier of bursts proved to be
a fractal with dimension Df = 1.25. Our analysis revealed that the pulse shape
and spatial evolution of bursts are correlated which can be exploited in materials’
testing. |
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