Spectral analysis of granular material reaction to long-term weak dynamic effect

Abstract

The paper demonstrates the similarity of alternating reaction of rocks to explosions to the response of a granular material to repetitive (up to 330 thousands) light shocks (3.85 -10{-3} J, frequency 1.33 Hz). The cause of both reactions is multiple forms of equilibrium of geomaterials. It has been stated that pressure of the sensor in a granular material subject to long-term weak effects doesn't relax to the hydrostatic one, but oscillates about it with the amplitude about its value. The spectral density of this process obeys the power dependence on the frequency; the exponent is typical for black noise.