Journal of Korean Tunnelling and Underground Space Association (한국터널지하공간학회 논문집)

Korean Tunnelling and Underground Space Association (한국터널지하공간학회)
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Effect of geological characteristics on differential weathering of low-graded metasedimentary rock slopes

저변성퇴적암 사면에서 지질특성이 차별풍화에 미치는 영향

  • Jeong, Hae-Geun (K-water Institute, Korea Water Resources Corporation) ;
  • Seo, Yong-Seok (Department of Earth and Environmental Sciences, Chungbuk National University) ;
  • Ihm, Myung-Hyeok (Department of Geotechnical Engineering for Disaster Prevention, Daejeon University)
  • 정해근 (한국수자원공사 K-water 연구원) ;
  • 서용석 (충북대학교 지구환경과학과) ;
  • 임명혁 (대전대학교 지반방재공학과)
  • Received : 2013.05.06
  • Accepted : 2013.05.21
  • Published : 2013.07.31
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Abstract

This study evaluates correlation between petrographic characteristics and weathering grade of low-graded metasedimentary rocks mainly consisting of phyllite. Weathering grade of rock material was determined based on the results of geological survey. The Schmidt hammer test was carried out to obtain estimates of strength of rock materials. Point counting and microscopic observation were also conducted to analyze mineral composition and to measure spacing of foliation for 9 rock specimens. As a result of microscopic analysis, as the weathering grade was lower, the quartz was found more in quantity, consequently making rock stronger against weathering process. On the other side, lower weathering grade of rock resulted in less content of mica which is weak against weathering process. In addition, the rock materials with closer foliation spacing are found to be weaker in strength and have higher weathering grade.

본 논문에서는 천매암을 중심으로 저변성퇴적암류에 속하는 암석을 대상으로 암석학적 특징과 풍화도의 상관성에 대하여 분석하였다. 현장 지질조사를 통하여 암석의 풍화도를 결정하였고, 구성암석의 강도 값을 추정하기 위하여 슈미트해머 테스트를 실시하였다. 9개 시료의 현미경 박편 관찰을 통하여 주구성광물의 부피비와 엽리의 간격을 측정하였다. 암석시료의 현미경 분석 결과에 의하면 풍화도가 낮을수록 풍화에 강한 석영성분이 많고, 풍화도가 높을수록 풍화에 약한 운모성분이 많은 것으로 나타났다. 또한 엽리 간격이 좁을수록 강도는 낮고 풍화도는 높은 것으로 나타났다.

Keywords

References

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