Line creep in paper peeling

Abstract

The dynamics of a "peeling front" or an elastic line is studied under creep (constant load) conditions. Our experiments show an exponential dependence of the creep velocity on the inverse force (mass) applied. In particular, the dynamical correlations of the avalanche activity are discussed here. We compare various avalanche statistics to those of a line depinning model with non-local elasticity, and study various measures of the experimental avalanche-avalanche and temporal correlations such as the autocorrelation function of the released energy and aftershock activity. From all these we conclude, that internal avalanche dynamics seems to follow "line depinning" -like behavior, in rough agreement with the depinning model. Meanwhile, the correlations reveal subtle complications not implied by depinning theory. Moreover, we also show how these results can be understood from a geophysical point of view.PACS numbers:

Statistics of acoustic emission in paper fracture: precursors and criticality

“…In that case the generic temporal properties are further discussed in Ref. [11]. Approaching a"main shock" in stationary experiment might be identical to approaching time at the maximum event rate in strain-driven non-stationary fracture experiment when we consider the behaviour of the event rateṅ.…”

Avalanches in Wood Compression

“…Data from small scales presents statistical laws like those from earthquake activity. An important question across the scales is whether (possible) correlations in crackling noise and deformation help to forecast large events or the final failure [9,10,13].…”

“…In experiments at constant stress rate, this occurs at a slightly lower waiting time, but the features are otherwise similar. The waiting times after an event of a certain energy present a power law relation for aftershocks (high energies followed by short waiting times) [13,36], which spans around five decades in energy with an exponent around 4. This relation is absent in the waiting time before an event.…”

“…Aftershocks and Omori's law -In the case of earthquakes, a mainshock is followed by smaller aftershocks, implying the famous seismology Omori's law [6,13,[34][35][36]: the number of aftershocks per unit time interval n(t) is n(t) = K(t + c) −1 with K and c constants. The modified law relates the aftershock sequence to the time elapsed from the mainshock time [13] t MS as a power law: r AS (t−t MS ) ∝ (t−t MS ) −p where r(t) is the event rate of aftershocks and p ∼ 1.…”

“…Aftershocks and Omori's law -In the case of earthquakes, a mainshock is followed by smaller aftershocks, implying the famous seismology Omori's law [6,13,[34][35][36]: the number of aftershocks per unit time interval n(t) is n(t) = K(t + c) −1 with K and c constants. The modified law relates the aftershock sequence to the time elapsed from the mainshock time [13] t MS as a power law: r AS (t−t MS ) ∝ (t−t MS ) −p where r(t) is the event rate of aftershocks and p ∼ 1. In fracture experiments, events of any energy could be considered as mainshocks to verify if such statistical laws hold [6,17].…”