Ultrasonic method for estimation of crack initiation stress

0481249 - GLÚ 2018 US eng C - Konferenční příspěvek (zahraniční konf.)
Petružálek, Matěj - Lokajíček, Tomáš - Svitek, Tomáš
Ultrasonic method for estimation of crack initiation stress.
51st US Rock Mechanics/Geomechanics Symposium. s. l.: American Rock Mechanics Association, 2017. ISBN N.
[US Rock Mechanics/Geomechanics Symposium /51./. San Francisco (US), 25.06.2017-28.06.2017]
Grant CEP: GA ČR GA13-13967S; GA ČR(CZ) GA16-03950S
Klíčová slova: ultrasonic * crack initiation stress
Kód oboru RIV: DB - Geologie a mineralogie

Stress strain behavior of low-porosity crystalline rocks is divided into four characteristic stages: crack closure, elastic region, stable crack growth and unstable crack growth which leads to brittle failure. The beginning of stable crack growth is called the crack initiation stress while the beginning of unstable microcracking is called the crack damage stress. This laboratory study presents a new technique for estimation of crack initiation threshold. The technique is based on the interpretation of measured ultrasonic attenuation. The attenuation method was tested on the set of 4 granite specimens during the uniaxial loading. The attenuation based crack initiation stresses were comparable with those determined by interpretation of stress-strain data and acoustic emission data.
Trvalý link: http://hdl.handle.net/11104/0276852