Bi-modular properties of sandstone inferred from seismic moment tensors of acoustic emissions

0578344 - GLÚ 2024 RIV GB eng J - Journal Article
Vavryčuk, Václav - Petružálek, Matěj - Lokajíček, Tomáš - Aminzadeh, Ali
Bi-modular properties of sandstone inferred from seismic moment tensors of acoustic emissions.
International Journal of Rock Mechanics and Mining Sciences. Roč. 171, November (2023), č. článku 105576. ISSN 1365-1609. E-ISSN 1873-4545
R&D Projects: GA ČR(CZ) GA22-00580S
Institutional support: RVO:67985831
Keywords : Acoustic emissions * Tensile cracks * Rock * Auxetic behaviour * Fracturing * Rock bi-modularity
OECD category: Environmental and geological engineering, geotechnics
Impact factor: 7.2, year: 2022
Method of publishing: Open access
https://www.sciencedirect.com/science/article/pii/S1365160923002502?via%3Dihub

We propose a novel method for studying the λ/μ ratio, the vP/vS ratio and Poisson's ratio of rocks based on the determination of highly accurate moment tensors of acoustic emissions (AEs). The validity of the method is verified on observations of 539 AEs recorded in a sandstone sample during a semi-circular bend test. We show that the sandstone exhibits the so-called bi-modular behaviour indicating that rock parameters significantly differ under compressive and tensile stress regimes. In addition, the zone characterized by highly tensile fractures is auxetic. For increasing shear component in AEs, Poisson's ratio increases and the auxetic effects disappear. The proposed approach for determining the λ/μ, vP/vS, and Poisson's ratios using AEs is fully independent of standard techniques based on measuring deformation of rock samples. The approach might find applications in detailed studies of rock behaviour under various stress conditions, in particular, in assessing the bi-modularity of rocks measured during a single experiment.
Permanent Link: https://hdl.handle.net/11104/0347353