JaLCDOI 10.18926/15447
FullText URL Mem_Fac_Eng_OU_28_1_129.pdf
Author Taniguchi, Takeo| Hirose, Sohichi| Ouchterlony Finn| Nakagawa Kohji| Miyaji Akihiko| Fukuoka Yasufumi|
Abstract The testing method of rock toughness is proposed by the international society of rock mechanics (ISRM), but the results may be influenced by the test pieces, and the details of the crack propagation and the stress intensity factors are not clarified through the testing. Also the experimental test requires tedious works for the preparation of test specimen and economical responsibility. The present study aims to simulate numerically the rock toughness testing which is proposed by ISRM. For this purpose, the authors propose a numerical method which can simulate the experimental testing, and they show the propriety of the proposed method by comparing the results with the experimental and other numerical methods. At the same time, they clarify the details of crack propagation behaviors in rocks, and show the change of the stress intensity factors. The proposed method is based on the displacement-type finite element method, and several techniques are introduced to obtain accurate solution of the mechanical behavior near the crack-tip area.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1993-11-30
Volume volume28
Issue issue1
Start Page 129
End Page 138
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307126
JaLCDOI 10.18926/15445
FullText URL Mem_Fac_Eng_OU_26_2_139.pdf
Author Hirose, Sohichi|
Abstract Scattering problems by a penny-shaped crack are solved using a time-domain boundary integral equation method, The crack is located in an infinite homogeneous, isotropic, linearly elastic solid, and is subjected to an oblique incident wave of either P-, SV-, or SH-wave, The hypersingular integral equation is solved to obtain near-field solutions as well as scattered far-fields. The accuracy of the present method is confirmed by comparing the near-field solutions for different arrangement of elements, Scattered far-fields are calculated for various incident waves, and their usefulness in quantitative non-destructive evaluation is discussed.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1992-03-28
Volume volume26
Issue issue2
Start Page 139
End Page 150
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307492
JaLCDOI 10.18926/fest/11607
FullText URL 002_089_098.pdf
Author Hirose, Sohichi|
Abstract A linear scattering inverse method based in the Kirchhoff approximation is formulated to determine the location and size of a crack in a solid. A characteristic function, which defines the size of a crack, can be reconstructed from the inverse Fourier transform of scattered amplitudes at far field. The inverse method is applied to ultrasonic data scattered by a crack in an aluminum specimen. Agreement between reconstructed characteristic functions and exact ones is not good enough, because experimental conditions do not coincide with theoretical ones. We can, however, evaluate the location and size of a crack from sharp minimum points reproduced at crack tips.
Publication Title 岡山大学環境理工学部研究報告
Published Date 1997-01-10
Volume volume2
Issue issue1
Start Page 89
End Page 98
ISSN 1341-9099
language 英語
File Version publisher
NAID 120002313621