Driving rate dependence of avalanche statistics and shapes at the yielding transition

Abstract

We study stress time series caused by plastic avalanches in athermally sheared disordered materials. Using particle-based simulations and a mesoscopic elasto-plastic model, we analyze size and shear-rate dependence of the stress-drop durations and size distributions together with their average temporal shape. We find critical exponents different from mean-field predictions, and a clear asymmetry for individual avalanches. We probe scaling relations for the rate dependency of the dynamics and we report a crossover towards mean-field results for strong driving.Comment: 5 pages, 3 figures, 1 table, supplementary material to be found at http://www-liphy.ujf-grenoble.fr/pagesperso/martens/documents/liu2015-sm.pd