Variation of Engineering Geological Characteristics of Jurassic Granite in Wonju Due to Freeze-Thaw Weathering

동결-융해 풍화에 의한 원주지역 쥬라기 화강암의 지질공학적 특성변화

  • Um, Jeong-Gi (Dept. of Energy Resources Engineering, Pukyong National University) ;
  • Woo, Ik (Dept. of Coastal Construction Engineering, Kunsan National University) ;
  • Park, Hyuck-Jin (Dept. of Geoinformation Engineering, Sejong University)
  • 엄정기 (부경대학교 에너지자원공학과) ;
  • 우익 (군산대학교 해양건설공학과) ;
  • 박혁진 (세종대학교 지구정보공학과)
  • Published : 2009.06.28

Abstract

An experimental study of the accelerated weathering was performed to investigate the variations of physicomechanical properties of deteriorated rocks due to freeze-thaw weathering for the Jurassic granite specimens from Wonju, Gangwon-do. Each complete cycle of freeze and thaw was lasted 24 hours, comprising 2 hours saturating in vacuum chamber, 8 hours freezing at -20$\pm1^{\circ}C$ and 14 hours thawing at room temperature. Freeze-thaw cycles were implemented with measuring the index physical properties as well as geometries of microfractures. The seismic velocity was found to decrease with increasing freeze-thaw cycles. On the other hand, absorption tends to increase with freeze-thaw cycles. In the end, it was concluded that variations of the index properties of deteriorated specimen depend on its initial properties and flaws in rock. The size and density of the traces of the microfracture on slab specimen were changed continuously with increasing freeze-thaw weathering. The results obtained in this study show that the box fractal dimension($D_B$) has the strong capability of quantifying the combined effect of size and density of the microfractures.

Keywords

weathered rocks;freeze-thaw;granite;microfracture;fractal dimension

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