Acoustic Emission Spectrum and Failure Prediction in Loaded Coal Specimens
V. L. SHKURATNIK1, P. V. NIKOLENKO1, A. E. KOSHELEV2
1Academician Melnikov Institute of Integrated Mineral Resources, Kryukovskii tupik 4, Moscow, 111020 Russia
2Gazprom geotekhnologii, ul. Stroitelei 8, Moscow, 119311
Keywords: каменный уголь, акустическая эмиссия, образец, спектр, одно- и трехосное нагружение, Кузнецкий угольный бассейн, Печерский угольный бассейн, mineral coal, acoustic emission, specimen, spectrum, uniaxial and triaxial loading, Kuznetsk and Pechora Coal Basins
Abstract
Mechanisms of change in the spectra of acoustic emission in specimens of mineral coal from Kuznetsk and Pechora Basins are experimentally determined in uniaxial and triaxial (Karman scheme) compression tests. It is shown that at the pre-failure stage in a specimen under uniaxial compression, the spectrum pattern of acoustic emission changes considerably, the amplitudes of low frequencies grow while the amplitudes of high frequencies reduce. Under the Karman scheme loading of specimens, the amplitudes of the low-frequency signals grow without the decrease in the high-frequency amplitudes, which is connected with the prevented opening of fractures under the influence of the hydrostatic pressure in the horizontal plane.
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