KSCE Journal of Civil and Environmental Engineering Research (대한토목학회논문집)

Korean Society of Civil Engeneers (대한토목학회)
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Variations of Geotechnical Characteristics Following Freeze-Thaw of Terra Nova Bay Rocks, Antarctica

남극 테라노바 만 편마암의 동결-융해에 따른 지반공학적 특성 변화

  • Received : 2013.02.14
  • Accepted : 2013.06.29
  • Published : 2013.07.30
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Abstract

Freeze-thaw tests were performed on gneiss samples collected from Terra Nova Bay, Antarctica in order to examine the engineering properties of rocks with slightly weathered (SW) and moderately weathered (MW). The tests were conducted under temperature ranging from $20{\pm}2^{\circ}C$ to $-20{\pm}2^{\circ}C$. A cycle of test consisted of 5 hours of freezing followed by another 5 hours of thawing under full saturation. In this paper, total 200 cycles of freeze-thaw test were performed with measurements of porosity, absorption, ultrasonic velocity, and shore hardness per each 20 cycle and that of uniaxial compressive strength (UCS) per each 50 cycle. The UCS of the SW rocks approximately decreased 0.07 MPa per a single cycle, while that of MW rocks decreased around 0.2 MPa per a single cycle. During the 200 cycles of SW rocks, the absorption increased from 0.23% to 0.39%, the P-wave velocity decreased from 4,054 m/s to 3,227 m/s and S-wave velocity decreased from 2,519 m/s to 2,079 m/s. Similarly, those of MW rocks changed from 0.65% to 1.6%, 3,207 m/s to 2,133 m/s and 2,028 m/s to 1,357 m/s. In conclusion, it was inferred that the properties of SW rocks experienced approximately 200-300 cycles of freeze-thaw process become close to those of MW rocks.

남극 암석의 동결-융해 풍화현상에 관한 연구를 위하여 테라노바 만 지역의 편마암을 대상으로 풍화등급에 따라 약한풍화(SW) 및 보통풍화(MW)로 분류하여 암석의 공학적인 특성 변화를 실험하였다. 동결-융해시험은 $-20{\pm}2^{\circ}C{\sim}20{\pm}2^{\circ}C$의 온도 조건에서 수행되었으며, 암석 시험편은 진공챔버에서 포화된 상태에서 5시간 동결과 5시간 융해 과정을 1 cycle의 동결-융해로 설정하였다. 본 논문에서는 전체 200 cycle의 동결-융해 과정을 진행하면서 20 cycle 마다 공극률, 흡수율, 초음파 속도 및 쇼어경도를 측정하였으며, 50 cycle 마다 일축압축시험을 수행하였다. SW 등급의 편마암은 동결-융해 1 cycle 마다 0.07 MPa 정도 일축압축강도가 감소하였으며, MW 등급의 암석은 0.2 MPa 정도 일축압축 강도가 감소하였다. 동결-융해가 200 cycle 진행되는 동안 SW 등급 암석의 흡수율은 0.23%에서 0.39%로 증가하였으며, P파 속도는 4,054 m/s에서 3,227 m/s로, S파 속도는 2,519 m/s에서 2,079 m/s로 감소하였다. 이와 유사하게 MW 등급 암석의 흡수율은 0.65%에서 1.6%로 증가하였으며, P파 속도는 3,207 m/s에서 2,133 m/s로, S파 속도는 2,028 m/s에서 1,357 m/s로 감소하였다. 동결-융해시험 결과, 남극 테라노바 만 지역의 SW 등급 편마암은 동결-융해가 200~300 cycle 반복될 경우 MW 등급 암석에 가깝게 풍화되는 것으로 밝혀졌다.

Keywords

References

  1. Baek, H. J. and Kwak, J. C. (2000). "Changes in the engineering geological properties of domestic gneisses due to weathering." Journal of Korean Society for Geosystem Engineering, Vol. 37, pp. 262-271 (in Korean).
  2. Barrosso, E. V., Policanov, H., Prestes, A., Nunes, A. L. S., Vargas, E. A. and Antunes, F. (1993). "Basic properties of weathered gneissic rocks in Rio de Janeiro." Geotechical Engineering of Hard Soils-Soft Rocks, Brazil, pp. 29-35.
  3. Bortz, S., Stecih, J., Wonneberger, B. and Chin, I. (1993). "Accelerated weathering in building stone." International Journal of Rock Mechanics and Mining Sciences, Vol. 30, pp. 1559-1562. https://doi.org/10.1016/0148-9062(93)90156-8
  4. Brito, A. T. (1981). Chemical and mineralogical study of a weathering profile in a migmatitic gneiss of the experimental site nr.1 at PUC-RJ, MSc Thesis, Catholic University of Rio de Janeiro, Brazil.
  5. Dearman, W. R. (1976). "Weathering classification in the characterization of rock: a revision. Bulletin." International Association of Engineering Geology, Vol. 13, pp. 123-127. https://doi.org/10.1007/BF02634776
  6. Dearman, W. R., Baynes, F. J. and Irfan, T. Y. (1978). "Engineering grading of weathered granite." Engineering Geology, Vol. 12, pp. 345-374. https://doi.org/10.1016/0013-7952(78)90018-2
  7. Debenham, F. (1921). "Recent and local deposits of McMurdo Sound Region In British Antarctic ('Terra Nova') Expedition, Natural History Report." Ceology, Vol. 1, No. 3, pp. 63-100.
  8. Fookes, P. G. and Hawkins, A. B. (1988). "Limestion weathering: Its Enginnering Significance and a Proposed Classification Scheme." Quarterly Journal of Enginneering Geology and Hydrogeology, Vol. 21, pp. 7-31. https://doi.org/10.1144/GSL.QJEG.1988.021.01.02
  9. Fookes, P. G., Dearman, W. R. and Franklin, J. A. (1971). "Some engineering aspects of rock weathering with field examples from Dartmoor and elsewhere." Quarterly Journal of Enginneering Geology and Hydrogeology, Vol. 4, No. 3, pp. 139-185. https://doi.org/10.1144/GSL.QJEG.1971.004.03.01
  10. Fookes, P. G., Gourley, C. S. and Ohikere, C. (1988). "Rock weathering in engneering time." Quarterly Journal of Enginneering Geology and Hydrogeology. Vol. 21, No. 1, pp. 33-57. https://doi.org/10.1144/GSL.QJEG.1988.021.01.03
  11. Hall, K. (1997). "Rock temperatures and implications for cold region weathering I: New Data from Viking Valley, Alexander Inland, Antarctica." Permafrost and Periglacial Processes, Vol. 8, pp. 69-90. https://doi.org/10.1002/(SICI)1099-1530(199701)8:1<69::AID-PPP236>3.0.CO;2-Q
  12. Irfan, T. Y. and Dearman, W. R. (1978). "Engineering classification and index properties of a weathered granite." International Association of Engineering Geology, Vol. 17, pp. 79-90. https://doi.org/10.1007/BF02634696
  13. ISRM (1981). Rock characterization testing & monitoring (ISRM suggested method), E.T Brown ed., Pergamon Press.
  14. Jang, H. S, Jang, B. A. and Lee, J. S. (2004). "Variations of engineering geological characteristics of the Cretaceous shale from the Pungam sedimentary basinin Kangwon-do due to freezing-thawing." The Journal of Engineering Geology, Vol. 14, No. 4, pp. 401-416 (in Korean).
  15. Kim, K. J., Kim, Y. S. and Hong, S. S. (2012). "Physical and mechanical characteristics of the Antarctic rocks exposed to the extreme environment." Journal of the Korean Society of Civil Engineers, 32, 6C, pp. 275-284 (in Korean). https://doi.org/10.12652/Ksce.2012.32.6C.275
  16. Kim, S. S. and Park, H. D. (1999). "A study on the change of rock properties using artificial weathering test." Journal of Korean Society for Geosystem Engineering, Vol. 36, pp. 141-149 (in Korean).
  17. Kolsky, H. (1963). Stress waves in solids, Dover Publications Inc., Mineola, N.Y.
  18. Korea Institute of Construction Technology (2011). Development of structural stability assessment and operation system for sustainable Antarcic research station construction(2), KICT2011-124 (in Korean).
  19. Korea Institute of Construction Technology (2012). Development of structural stability assessment and operation system for sustainable Antarcic research station construction(3), KICT2012-099 (in Korean).
  20. Kyoya, T., Baek, Y. and Onda, C. (2000). "On deterioration of Oya-tuff in freezing-thawing cycle and its quantitative description." Journal of Japan Society of Civil Engineers, Vol. 652, pp. 103-114 (in Japanese).
  21. Lumb, P. (1983). "Engineering properties of fresh and decomposed igneous rocks from Hong Kong." Engineering Geology, Vol. 19, No. 2, pp. 81-92. https://doi.org/10.1016/0013-7952(83)90027-3
  22. Nicholson, D. T. and Nicholson, F. H. (2000). "Physical deterioration of sedimentary rocks subjected to experimental freeze-thaw weathering." Earth Surface Processes and Landforms, 25, pp. 1295-1308. https://doi.org/10.1002/1096-9837(200011)25:12<1295::AID-ESP138>3.0.CO;2-E
  23. Onodera, R. F., Yoshinaka, R. and Oda, M. (1974). "Weathering and its relation to mechanical properties of granite." Proceedings 3rd, International Congress of Society for Rock Mechanics, Denver, Vol. 2A, pp. 71-78.
  24. Price, D. G. (1995). "Weathering and weathering processes." Quarterly Journal of Engineering Geology, Vol. 28, No. 3, pp. 243-252. https://doi.org/10.1144/GSL.QJEGH.1995.028.P3.03
  25. Serta, H. B. (1986). Geological and geotechnical sapects of the residual soil from experimental site n.2 at PUC-RJ, MSc Thesis, Catholic University of Rio de Janeiro, Brazil.
  26. Thorn, C. E. (1988). "Nivation: a geomorphic chimera. In: Clark, M. J., ed." Advances in Periglacial Geomorphology, John Wiley and Sons, Chichester, pp. 3-31.

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