We present an experimental study of the compaction dynamics fortwo-dimensional anisotropic granular systems. Compaction dynamics is measuredat three different scales : (i) the macroscopic scale through the packingfraction $\rho$, (ii) the mesoscopic scale through both fractions of alignedgrains $\phi_{a}$ and ideally ordered grains $\phi_{io}$, and (iii) themicroscopic scale through both rotational and translational grain mobilities$\mu_{r,t}$. The effect of the grain rotations on the compaction dynamics hasbeen measured. At the macroscopic scale, we have observed a discontinuity inthe late stages of the compaction curve. At the mesoscopic scale, we haveobserved the formation and the growth of domains made of aligned grains. From amicroscopic point of view, measurements reveal that the beginning of thecompaction process is essentially related to translational motion of thegrains. The grains rotations drive mainly the process during the latest stagesof compaction.
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