We present the experimental and numerical studies of a 2D sheared amorphous material constituted of bidisperse photo-elastic disks. We analyze the statistics of avalanches during shear including the local and global fluctuations in energy and changes in particle positions and orientations. We find scale free distributions for these global and local avalanches denoted by power-laws whose cut-offs vary with inter-particle friction and packing fraction. Different exponents are found for these power-laws depending on the quantity from which variations are extracted. An asymmetry in time of the avalanche shapes is evidenced along with the fact that avalanches are mainly triggered from the shear bands. A simple relation independent from the intensity, is found between the number of local avalanches and the global avalanches they form. We also compare these experimental and numerical results for both local and global fluctuations to predictions from meanfield and depinning theories.

翻译：我们展示了由双维剪切的光弹性磁盘构成的两维变形材料的实验和数字研究。 我们分析了剪切期间雪崩的统计数字,包括当地和全球的能源波动以及粒子位置和方向的变化。 我们发现这些全球和地方雪崩的分布规模是免费的,由权力法则决定,其截断点因粒子摩擦和包装部分而不同。 根据提取变异的数量,为这些电源法找到不同的推算符。 雪崩形状的时势不对称,以及主要由剪切带触发的事实都得到了证明。 与强度无关的简单关系是当地雪崩数量与它们形成的全球雪崩数量之间。 我们还将这些地方和全球波动的实验和数字结果与中下游和下游理论的预测作了比较。