Journal of the Korean Geotechnical Society (한국지반공학회논문집)

Korean Geotechnical Society (한국지반공학회)
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A Case Study on Geotechnical Properties and Weathering Degree of Weathered Granite Rock

화강 풍화암의 지반특성 및 풍화도 평가에 대한 사례 연구

  • Lee, Seung-Hwan (Dept. of Civil & Environmental Engrg., Seoul National Univ.) ;
  • Yoo, Byeong Soo (Dept. of Civil & Environmental Engrg., Seoul National Univ.) ;
  • Chung, Choong-Ki (Dept. of Civil & Environmental Engrg., Seoul National Univ.)
  • 이승환 (서울대학교 건설환경공학부) ;
  • 유병수 (서울대학교 건설환경공학부) ;
  • 정충기 (서울대학교 건설환경공학부)
  • Received : 2017.11.06
  • Accepted : 2017.12.13
  • Published : 2017.12.31
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Abstract

Site investigation including boring and various in-situ borehole test (Pressuremeter test, Borehole shear test, Downhole test, Suspension PS logging, Density logging) and X-ray fluorescence analysis for rock core sample were performed to estimate geotechnical properties and weathering degree of weathered granite rock in Goyang. Deformation modulus, shear strength parameter and shear wave velocity estimated through in-situ borehole test had a tendency to increase with depth. And several chemical weathering indices evaluated by X-ray fluorescence analysis had a general tendency of reducing weathering degree in accordance with depth. Also, relationship between VR determined as a representative weathering index and the geotechnical properties was analyzed.

고양 지역의 화강 풍화암 지층을 대상으로 시추조사 및 다양한 현장 시추공 시험(프레셔미터시험, 공내전단시험, Downhole test, Suspension PS 검층, 밀도검층)을 수행하였고, 채취한 풍화암 코어시료에 대한 X선 형광분석을 실시하여 풍화도를 평가하였다. 현장 시추공 시험 결과로부터 변형계수, 전단강도 정수, 전단파 속도 등을 평가하였고, 심도에 따라 각 지반특성 값이 증가하는 경향을 확인하였다. X선 형광분석을 통해 산정한 화학적 풍화지수는 심도에 따라 풍화도가 감소하는 일반적인 경향을 나타냈으며, 대표적 풍화지수인 VR과 풍화암의 지반특성과의 관계를 분석하였다.

Keywords

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