• The Journal of Engineering Geology
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• v.18 no.4
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• pp.459-470
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• 2008

Types of slope failure related to cut slope stability are interpreted through case analyses, and also factors affecting structurally controlled instability investigated, which are developed by geologic structures along a national road No. 25 across the Cheongwon and Boeun-Guns, Chungbuk. Engineering properties such as orientation, persistence, roughness and uniaxial compressive strength of joints are analyzed by square-inventory method in three areas with well-preserved outcrops. The study area is located in Ogcheon folded bet, and are composed of quartz-schist and quartzite in the Midongsan Formation and phyllite in the Ungyori Formation. Flexural beds by folding, schistosity and cleavage besides joints are developed due to slight metamorphism. Various types of joints developed by folding are formed such as strike-parallel, strike-perpendicular, wedge and wrench joint sets by both initially regional and later superposed folding. Factors of slope instability are created by crossing the orientations of joint, cleavage, bedding and slope one another. In the case that the orientation of a slope is coincident with one of beds, factors causing large-scale failure including plane failure are increased greatly. Also in the region that orientations of the slope and bed are crossed each other at high angle, only local and minor failures are shown in the slope.

• Journal of the Speleological Society of Korea
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• no.86
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• pp.1-7
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• 2008

지질구조는 카르스트의 층위와 구조상의 배열에 있어서 다양한 카르스트의 지형을 결정한다. 카르스트의 발달은 조산 및 조륙운동, 석회암층의 두께, 구성물질의 유형, 단층 및 습곡의 다양성, 주향 및 절리면의 빈도, 기후변화 및 기상환경, 수문 및 유수의 유형, 토지이용 현황 외 환경오염 등에 따라서 차별성을 나타낸다. 특히 지질구조에 따른 카르스트의 발달은 석회암 등이 유수의 작용에 커다란 용해작용의 영향을 받으므로 지질구조의 요인인 단층과 습곡현황과 절리와 균열 등에 의한 카르스트의 발달에 가장 큰 기여를 한다. 지질구조에 의하여 카르스트 지표지형에는 karren과 hum, mogotes, doline와 uvala, towers, springs, 구조적 유역, Closed Systems 등이 형성되고, 지하지형에는 Phreatic 동굴, Vados 동굴, Chambers, Multileveling cavities, Vertical shafts 등이 형성되는 다양성을 가진다. 한반도에서는 습곡구조에 의한 동공의 발달이 탁월하며, 다단계 및 급사면형 동굴의 유형이 다양하게 분포되고 있다.