caa a22 4500 60618886X CHVBK 20210128100847.0 cr unu---uuuuu 210128e20150501xx s 000 0 eng 10.1007/s10891-015-1252-0 doi (NATIONALLICENCE)springer-10.1007/s10891-015-1252-0 Amplitude-Frequency Analysis of Signals of Acoustic Emission from Granite Fractured at Elevated Temperatures [Elektronische Daten] [I. Shcherbakov, A. Chmel′] The problem of stability of underground structures serving to store radioactive waste, to gasify carbon, and to utilize geothermal energy is associated with the action of elevated temperatures and pressures. The acoustic-emission method makes it possible to monitor the accumulation of microcracks arising in stress fields of both thermal and mechanical origin. In this report, the authors give results of a laboratory investigation into the acoustic emission from granite subjected to impact fracture at temperatures of up to 600°C. An amplitude-frequency analysis of acousticemission signals has enabled the authors to evaluate the dimension of the arising microcracks and to determine their character (intergranular or intragranular). It has been shown that intergranular faults on the boundaries between identical minerals predominate at room temperature (purely mechanical action); at a temperature of 300°C (impact plus thermoelastic stresses), there also appear cracks on the quartz-feldspar boundaries; finally, at temperatures of 500-600°C, it is intragranular faults that predominate in feldspar. The dimensions of the above three types of microcracks are approximately 2, 0.8, and 0.3 mm respectively. Springer Science+Business Media New York, 2015 granite nationallicence impact fracture nationallicence thermal action nationallicence acoustic emission nationallicence microcracks nationallicence Shcherbakov I. A. F. Ioffe Physical-Technical Institute, Russian Academy of Sciences, 26 Politekhnicheskaya Str., 194021, St. Petersburg, Russia aut Chmel′ A. A. F. Ioffe Physical-Technical Institute, Russian Academy of Sciences, 26 Politekhnicheskaya Str., 194021, St. Petersburg, Russia aut Journal of Engineering Physics and Thermophysics Springer US; http://www.springer-ny.com 88/3(2015-05-01), 786-790 1062-0125 88:3<786 2015 88 10891 https://doi.org/10.1007/s10891-015-1252-0 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s10891-015-1252-0 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Shcherbakov I. A. F. Ioffe Physical-Technical Institute, Russian Academy of Sciences, 26 Politekhnicheskaya Str., 194021, St. Petersburg, Russia aut NATIONALLICENCE 700 1- Chmel′ A. A. F. Ioffe Physical-Technical Institute, Russian Academy of Sciences, 26 Politekhnicheskaya Str., 194021, St. Petersburg, Russia aut NATIONALLICENCE 773 0- Journal of Engineering Physics and Thermophysics Springer US; http://www.springer-ny.com 88/3(2015-05-01), 786-790 1062-0125 88:3<786 2015 88 10891