Όνομα Περιοδικού:Natural Hazards and Earth System Sciences
This paper presents a wavelet based method of
analysis of experimentally recorded weak electric signals
from marble specimens which have undergone successive
abrupt step loadings. Experimental results verify the existence
of “memory effects” in rocks, as far as the current
emission is concerned, akin to the “Kaiser effect” in acoustic
emissions, which accompany rock fracturing. Macroscopic
signal processing shows similarities and differences between
the currents emitted during successive loading and wavelet
analysis can reveal significant differences between the currents
of each loading cycle that contain valuable information
for the micro and macro cracks in the specimen as well
as information for the remaining strength of the material.
Wavelets make possible the time localization of the energy
of the electric signal emitted by stressed specimens and can
serve as method to differentiate between compressed and uncompressed
samples, or to determine the deformation level
of specimens.