• Proceedings of the KSEG Conference
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• 2002.04a
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• pp.109-114
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• 2002

Development of a three-dimensional mine visualization model for a section of the mine is addressed first. Discontinuity orientation and location information was taken from this visualization model for use in slope stability analyses. Estimated shear strength properties of discontinuities and mechanical properties of intact rock from the rock mass samples obtained from the mine are discussed next. The third part of the paper is focused on the results obtained for maximum safe slope angles for the section considered of the mine based on block theory analysis conducted under only the gravitational forces using the mapped discontinuities at the mine. Finally, the effects of water that exist in the rock mass, a tension crack, slope face inclination, overall wedge height and double benching on factor of safety of wedge stability are illustrated through limit equilibrium slope stability analyses conducted on a single tetrahedral wedge belonging to potential key block category that exist in the investigated area of the mine.

• Journal of the Korean Geotechnical Society
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• v.17 no.5
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• pp.17-27
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• 2001

지하 굴착공동의 천장면에 형성되는 잠재적 키블록의 존재성과 운동학적 거동 양상 및 안정성을 해석적으로 분석할 수 있는 시스템을 개발하였다. 천장에서 측정된 절리들의 상대적인 위치와 방향성 자료를 이용하여 데이타베이스를 구축하였으며, 굴착설계도와 연계된 전산절리도를 작성하였다. 잠재적 키블록의 존재성과 거동양상은 사면체로 가정된 블록 옆면의 3차원 공간에서의 평면식을 절리의 방향성에 의거하여 구성하며 대수학적으로 분석되었다. 블록의 안정성 분석은 자중에 의해 미끄러짐이 발생되는 블록면의 공간 기하학적 특성을 고려하여 수행하였다. 개발된 분석시스템의 현장활용성을 검증하기 위하여 언양 자수정동굴에서 키블록 형성 및 거동양상을 조사하여 분석결과와 비교하였다.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.15 no.1
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• pp.57-65
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• 2011

In this paper, a good quality mesh generation for the finite element method is investigated for artificial hip joint simulations. In general, bad meshes with a large aspect ratio or mixed elements can give rise to excessively long computational running times and extremely high errors. Typically, hexahedral elements outperform tetrahedral elements during three-dimensional contact analysis using the finite element method. Therefore, it is essential to mesh biologic structures with hexahedral elements. Four meshing schemes for the finite element analysis of an artificial hip joint are presented and compared: (1) tetrahedral elements, (2) wedge and hexahedral elements, (3) open cubic box hexahedral elements, and (4) proposed hexahedral elements. The proposed meshing scheme is to partition a part before seeding so that we have a high quality three-dimensional mesh which consists of only hexahedral elements. The von Mises stress distributions were obtained and analyzed. We also performed mesh refinement convergence tests for all four cases.

• Economic and Environmental Geology
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• v.2 no.4
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• pp.1-21
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• 1969

The Sin po fluorite deposit is of a fissure vein type which strikes $N75^{\circ}E$, dips $80^{\circ}SE$, and is embedded in the pre-Cambrian crystalline schist. The vein is 1 meter in average in thickness, about 800 meters in length and nearly 400 meters in depth. Narrow veins of crustified fluorites and agatic quartz are discontinuously embedded in the quartz gangue. Two-phase fluid inclusions, which are available for the homogenization method by using the Heating Stage Microscope 350, are found in the fluorite crystals. Most of the fluid inclusions are primary in origin and mainly composed of liquid phase associated with minor gas phase. They are tetrahedral, rounded-tubular, wedge shaped, rectangulartrapezoid, and irregular in shape. The maximum diameter of inclusions is 0.5mm and the minimum, 0.03mm, ranging from 0.2mm to 0.08mm in an average. The homogenization temperatures obtained from the test are $135-147^{\circ}C$, $125-138^{\circ}C$, $121-137^{\circ}C$, $116-133^{\circ}C$ and $106-128^{\circ}C$ in greenish, bluish, violet, light grayish blue, colorless and pinkish fluorites respectively. The range of formation temperatures of fluorites is $106-147^{\circ}C$. Therefore, the fluorite deposit of Sinpo Mine is considered to be of low temperature hydrothermal origin. The isothermal lines were drawn on the longitudinal section of the vein from the data of homogenization test. According to the results, the central and lower parts of the ore shoot in the west ore body show the higher temperatures of $130-138^{\circ}C$ and the peripheral and upper parts of it show the lower temperatures of $108-128^{\circ}C$. It seems that the isothermal trend roughly coinside with the pitch of the ore shoot.