Application of the shear-tensile source model to acoustic emissions in Westerly granite

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00007064%3AK01__%2F20%3AN0000064" target="_blank" >RIV/00007064:K01__/20:N0000064 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/67985530:_____/20:00531789 RIV/67985831:_____/20:00531789

Výsledek na webu

<a href="https://www.sciencedirect.com/science/article/abs/pii/S1365160919310263?via%3Dihub" target="_blank" >https://www.sciencedirect.com/science/article/abs/pii/S1365160919310263?via%3Dihub</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.ijrmms.2020.104246" target="_blank" >10.1016/j.ijrmms.2020.104246</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Application of the shear-tensile source model to acoustic emissions in Westerly granite

Popis výsledku v původním jazyce

Traditionally in seismology and in acoustic emission (AE), full moment tensor (MT) is applied as a default model of the mechanism. We present an alternative - an application of shear tensile crack (STC) source model to AEs generated by uniaxial compression loading of Westerly granite. The advantages of STC over the conventional MT are as follows: (i) contrary to the MT, the STC is physical source since it describes straight and simple fracture modes anticipated inside a loaded sample, namely the shear-slip and both of opening and closing tensile cracks; and (ii) the STC is simpler because it is described by fewer parameters (five instead of six required for an unconstrained MT), an essential feature for stabilizing the inverse problem. Better suitability of STC over MT is demonstrated by three exemplary AEs (tensile, shear, and combined). The obtained results were confirmed using a statistical analysis of 1630 reliably determined source mechanisms. The STC, as compared to the MT, provides smaller confidence regions for orientation and even smaller regions for decomposition parameters. Thus, the STC solution appeared to be substantially more useful than the MT, namely for mechanisms with a high content of non-double-couple (non-DC) component, as it allowed better distinction between tensile and shear AEs. Grain scale cracks of tension and combined source type, localized within the middle-height circumferential portion of the specimen, dominated fracturing. Azimuthal distribution of fault planes was found to be approximately uniform for all three source types. The fault dip increased with increasing content of the non-DC component. The average values were 16 degrees, 21 degrees, and 26 degrees for the tensile, combined and shear source types, respectively. The specimen failed by flaking in areas of a high AE activity. AE locations and failure mechanisms indicate a perfect confinement end-boundary conditions between the tested specimen and the loading platens.

Název v anglickém jazyce

Application of the shear-tensile source model to acoustic emissions in Westerly granite

Popis výsledku anglicky

Traditionally in seismology and in acoustic emission (AE), full moment tensor (MT) is applied as a default model of the mechanism. We present an alternative - an application of shear tensile crack (STC) source model to AEs generated by uniaxial compression loading of Westerly granite. The advantages of STC over the conventional MT are as follows: (i) contrary to the MT, the STC is physical source since it describes straight and simple fracture modes anticipated inside a loaded sample, namely the shear-slip and both of opening and closing tensile cracks; and (ii) the STC is simpler because it is described by fewer parameters (five instead of six required for an unconstrained MT), an essential feature for stabilizing the inverse problem. Better suitability of STC over MT is demonstrated by three exemplary AEs (tensile, shear, and combined). The obtained results were confirmed using a statistical analysis of 1630 reliably determined source mechanisms. The STC, as compared to the MT, provides smaller confidence regions for orientation and even smaller regions for decomposition parameters. Thus, the STC solution appeared to be substantially more useful than the MT, namely for mechanisms with a high content of non-double-couple (non-DC) component, as it allowed better distinction between tensile and shear AEs. Grain scale cracks of tension and combined source type, localized within the middle-height circumferential portion of the specimen, dominated fracturing. Azimuthal distribution of fault planes was found to be approximately uniform for all three source types. The fault dip increased with increasing content of the non-DC component. The average values were 16 degrees, 21 degrees, and 26 degrees for the tensile, combined and shear source types, respectively. The specimen failed by flaking in areas of a high AE activity. AE locations and failure mechanisms indicate a perfect confinement end-boundary conditions between the tested specimen and the loading platens.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10700 - Other natural sciences

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2020

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES

ISSN

1365-1609

e-ISSN

1873-4545

Svazek periodika

128

Číslo periodika v rámci svazku

104246

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

12

Strana od-do

1-12

Kód UT WoS článku

000536484200008

EID výsledku v databázi Scopus

2-s2.0-85079340829