The Variation of Compressional Wave Velocity with Degree of Saturation in Granites

  • Lee, Su-Gon (Dept. of Civil Eng.. The University of Seoul)
  • Published : 1999.06.01

Abstract

The measurement of sonic velocities is commonly used as an index of engineering properties of rock, but it is not widely appreciated that this velocity can change markedly with the degree of saturation of the sample. This paper records the nature of this variation as seen in samples of Korean granite. The ISRM method of testing suggested for this index can also create difficulties, especially if vaseline is used as a coupling agent, and invades the samples, and if the sample volume changes with degree of saturation. Careful measurements of the natural variation in sonic velocity that occur in a sample whose saturation is gradually increased may be a means of assessing the relic stresses within it.

암석의 탄성파속도를 측정하는 방법은 암석의 공학적 특성을 나타내는 하나의 지표로서 일반적으로 인식되고 있어서 우리나라에서도 $\lower right quadrant건설\; 표준품셈\upper left quadrant$등의 암판정 기준으로서 보편적으로 사용되고 있다. 그러나 암석의 탄성파속도는 시료의 함수상태에 따라서 크게 변화하는 사실을 충분히 인식하지 못하고 있으므로 본 논문은 한국화강암에서 관찰된 변화특성을 설명한다. 국제 암반역학회에서 추천하고 있는 암석의 탄성파속도 측정방법도 역시 실험상의 어려움이 있는데, 예를 들면 암석시료의 양쪽 끝에서 탄성파가 잘 측정되도록 하기 위하여 사용되는 바셀린이 암석 시료내로 침투하는 경우가 하나의 문제점이고, 또한 암석시료가 함수됨에 따라서 시료의 체적이 팽창하는 경우에도 해석상의 어려움이 있다. 또한 서서히 함수정도를 증가시키는 경우에 암석시료내에서 탄성파속도의 변화를 관찰하여 보면 암석시료내에 존재하는 잔류응력을 파악하는 한 방법으로서도 사용될 수도 있다는 것을 알 수 있다.

Keywords

References

  1. Journal of Geophysical Research v.65 The Velocity of Compressional Waves in Rocks to 10 Kilobars Birch,F.
  2. Proceedings of the 3rd Congress of the International Society for Rock Mechanics v.2 The Influence of Water on Some Rock Properties Broch,E.
  3. Proceedings of the 3rd Canadian Rock Mechanics Symposium The Influence of Mosture Content on the Compressive Strength of Rock Colback,P.S.B.;Wild,B.L.
  4. Air Force Weapons Laboratory Technical Report, AFWL-TR-65-116 Enginering Classification and Index Properties for Intact Rock Deere,D.U.;Miller,R.P.
  5. Ph.D. thesis. University of London Engineering Geology of Weak Sandstones Dobereiner,L.
  6. International Geology Review v.11 no.5 New Data on Velocity of Elastic Waves in Crystalline Rocks as a Function of Moisture Dortman,N.B.;Magid,M.Sh.
  7. Engineering Geology and Rock Mechanics v.1 Duncan,N.
  8. La M canique des Roches Appliqu e aux Duvrages, du G nie Civil by Marc panet (et al.) Characterization of Rocks: Laboratory Tests Fourmaintraux,D.
  9. Engineering Geology-Rock in Engineering Construction Goodman,R.E.
  10. Proceedings of the 7th Southeast Asian Geotechnical Conference v.1 The Description and Classification of Weathered Rocks in Hong Kong for Engineering purposes Hencher,S.R.;Matrtin,R.P.
  11. U.S. National bureau of Standards, Research Paper 2087 v.44 Thermal and Moisture Expansion Studies of Some Domestic Granites Hockman,A.;Kessler,D.W.
  12. Proceedings of the 1st Congress of the International Society of Rock Mechanics v.1 An Attempt ot Estimate the Degree of Weathering of Intrusive Rocks from Their Physico-Mechanical Properties Iliev,I.G.
  13. International Journal of Rock Mechanics and Mining Science & Geomechanics Bastracts v.15 no.2 Suggested Methods for Determing Sound Velocity ISRM(International Society of Rock Mechanics)
  14. International Journal of Rock Mechanics and Mining Science & Geomechanics Abstracts v.16 no.2 Suggested Methods for Determinig Water Content, Porosity, Density, Absorption and Related Properties and Swelling and Slake-Durability Index Properties ISRM(Interantional Society of Rock Mechanics)
  15. Bulletin of the International Association of Engineering Geology v.17 Engineering Classification and Index properties of a Weathered Granite Irfan,T.Y.;Dearman,W.R.
  16. Geophysics v.31 no.1 Wave Velocities in Rocks as a Function of Changes in Overburden Pressure and Pore Fluid Saturants King,M.S.
  17. Handbook on Mechanical Properties of Rocks v.2 Lama,R.D.;Vutukuri,V.S.
  18. Quarterly Journal of Engineering Geology v.22 no.1 A Revision of the Description and Classification of Weathered Granite and its Application to Granites in Korea Lee,S.G.;de Freitas,M.H.
  19. Proceedings of International Symposium of Rock Mechanics Rock Swelling Test Nascimento,U.;Oliveira,R.;Graca,R.
  20. Earth and Planetary Science Letters v.7 The Effect of Saturation on Velocity in Low Porosity Rocks Nur,A.;Simmons,G.
  21. Geophysical Exploration v.28 no.5 On the Variation of Propagation Velocity of Elastic Waves in Water Saturated Forous Rocks, Part 2 Omi,M.;Inoue,M.
  22. International Journal of Rock Mechanics and Mining Science & Geomichanics Abstracts v.10 Laboratory Studies on Kolar Rocks Ramana,Y.V.;Venkatanarayana,B.
  23. Earth Science Reviews v.12 To Earch Plutonic Rock its Proper Name Streckeisen,A.
  24. Geophysics v.34 no.1 An automated Ultrasonic Pulse Measurement System Thill,R.E.;Bur,T.R.
  25. International Journal of Rock Mechanics and Mining Science & Geomechanics Abstracts v.10 Velocity Anisotropy in Dry and Saturated Rock Spheres and its Relation to Rock Fabric Thill,R.E.;Bur,T.R.;Steckley,R.C.
  26. Proceedings of the 3rd International Congress of the International Association of Engineering Geology v.1 Influence of Weathering on the Mechanical Properties of Granitic Rocks Uriel,S.;Dapena,E.
  27. Journal of Geophysical Research v.80 The Effects of Water and Pressure on Velocities of Elastic Waves in a Foliated Rock Wang,C.;Lin,W.;Wenk,H.
  28. Geological Society Engineering Geology Special Publication no.3 Discussion Sessions 3 and 4: in Groundwater in Engineering Geology West,G.
  29. Geophysics v.23 An Experimental Investigation of Factors Affection Elastic Wave Velocities in Porous Media Wyllie,M.R.J.;Gregory,A.R.;Gardner,G.H.F.
  30. Geophysics v.21 Elastic Wave Velocities in Heterogeneous and Porous Media Wyllie,M.R.J.;Gregory,A.R.;Gardner,L.W.