Number of the records: 1
Acoustic emission in a laboratory: mechanism of microearthquakes using alternative source models
- 1.
SYSNO ASEP 0493426 Document Type J - Journal Article R&D Document Type Journal Article Subsidiary J Článek ve WOS Title Acoustic emission in a laboratory: mechanism of microearthquakes using alternative source models Author(s) Petružálek, Matěj (GLU-S) RID, SAI, ORCID
Jechumtálová, Zuzana (GFU-E) ORCID, RID
Kolář, Petr (GFU-E) ORCID, RID
Adamová, Petra (GFU-E) ORCID, RID
Svitek, Tomáš (GLU-S) SAI, RID
Šílený, Jan (GFU-E) ORCID, RID
Lokajíček, Tomáš (GLU-S) RID, SAI, ORCIDSource Title Journal of Geophysical Research-Solid Earth. - : Wiley - ISSN 2169-9313
Roč. 123, č. 6 (2018), s. 4965-4982Number of pages 18 s. Publication form Print - P Language eng - English Country US - United States Keywords acoustic emission ; source mechanism ; shear-tensile crack ; moment tensor Subject RIV DC - Siesmology, Volcanology, Earth Structure OECD category Volcanology Subject RIV - cooperation Institute of Geology - Geology ; Mineralogy R&D Projects GA16-03950S GA ČR - Czech Science Foundation (CSF) Institutional support GFU-E - RVO:67985530 ; GLU-S - RVO:67985831 UT WOS 000439933200027 EID SCOPUS 85050076217 DOI 10.1029/2017JB015393 Annotation Here a shear-tensile crack (STC) model is presented as suitable for acoustic emission (AE) events. Experimental data were obtained from a uniaxial compression test performed on a Westerly Granite specimen using a 14-channel AE monitoring system. The advantages of the STC versus a traditional MT (moment tensor) approach are as follows: (i) it is a physical source, contrary to the MT, since the STC describes the straight and simple fracture modes anticipated inside a loaded sample, namely, the shear slip and both the opening and closing tensile cracks, and (ii) it is simpler because it is described by fewer parameters (five instead of the six required for an unconstrained MT), which is essential for solving the inverse problem. The presented STC procedure was tested on 38 AE events selected over a range of 50-98% for the uniaxial compressive strength. As compared to the MT model, the STC model displayed a similar fit for input data while providing far smaller confidence regions. The results indicate a more certain determination for the mechanism of orientation and improved reliability for the decomposition components. In addition, use of STC model allowed better distinction between tension and shear type for AE events, which may be crucial for recognizing an approaching failure. For our experiment, application of the STC model proved to be useful for recognizing the threshold of unstable microcracking and indicative for determining the failure plain orientation. Workplace Geophysical Institute Contact Hana Krejzlíková, kniha@ig.cas.cz, Tel.: 267 103 028 Year of Publishing 2019
Number of the records: 1