• 터널과지하공간
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• 제29권5호
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• pp.332-345
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• 2019

평사투영도에서 불연속면을 대표하는 유일한 점으로 정의되는 최대경사벡터를 해당 면의 경사와 경사방향에 의거하여 형성하였다. 평사투영해석에서 평면의 극점이 대원과 역방향에 제도되는 것에 비해 최대경사벡터는 대원의 최대 경사지점에 위치하여 불연속면의 미끄러짐 방향을 직접 투영도 상에서 지시한다. 투영도 상에서 불연속면의 거동방향을 직접적으로 지시하는 최대경사벡터를 활용하여 평면 및 전도파괴 양상을 직관적으로 확인하였다. 특히 평면 파괴의 경우 블록의 옆면을 형성하는 고 경사 절리의 존재를 확인하여 실제 미끄러짐 블록의 형성가능성을 산정하였다. 또한 사면 방향과 반대방향을 갖는 고경사절리들의 존재를 확인하여 3각형 단면을 갖는 미끄러짐 블록의 형성여부를 판별하고 안전율을 도출하였으며, 4각형 단면을 갖는 가장 취약한 블록의 안전율과 비교분석하였다. 쐐기파괴 경우에는 절리면 교차에 의해 형성되는 쐐기의 기저선 방향이 최대경사벡터 속성을 지니고 있어 쐐기파괴 영역을 평면 및 전도파괴 영역이 제도된 투영도 상에 함께 도시하여 분석을 수행하였다. 특히 쐐기 상부 면을 형성하는 절리를 추출할 수 있어 전체 쐐기형상을 추정하고 역학적 거동분석을 수행하는데 요구되는 쐐기의 기하학적 특성자료를 도출하는 토대를 확립하였다.

• Geomechanics and Engineering
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• 제17권3호
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• pp.237-245
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• 2019

In deep mixed rock strata, a double shield TBM (DS-TBM) is easy to be entrapped by a large force during tunneling. In order to reduce the probability of the entrapment, we need to investigate a favorable driving direction, either driving with or against dip, which mainly associates with the angle between the tunneling axis and strike, ${\theta}$, as well as the dip angle of rock strata, ${\alpha}$. We, therefore, establish a 3DEC model to show the changes of displacements and contact forces in mixed rock strata through LDP (longitudinal displacement profile) and LFP (longitudinal contact force profile) curves at four characteristic points on the surrounding rock. This is followed by a series of numerical models to investigate the favorable driving direction. The computational results indicate driving with dip is the favorable tunneling direction to reduce the probability of DS-TBM entrapment, irrespective of ${\theta}$ and ${\alpha}$, which is not in full agreement with the guidelines proposed in RMR. From the favorable driving direction (i.e., driving with dip), the smallest contact force is found when ${\theta}$ is equal to $90^{\circ}$. The present study is therefore beneficial for route selection and construction design in TBM tunneling.

• 자원환경지질
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• 제33권2호
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• pp.117-128
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• 2000

Regional evaluations of slope stability by the failure criterion and by environmental geological factors were conducted. The failure criterion is the general conditions for plane failure which consider the geometrical conditions between geological discontinuities and topographical slope planes. The factor focused in this condiction is dip and dip direction. Geostatics, named semivariogram was used for establishing structural domains in slope stability evaluation by the failure criterion. The influential range was calculated to 6 km in the case of dip direction of dominant joint set and 7 km in the case of dip of the same dominant joint set. Then applying this failure criterion to the study area produced a slope stability map using the established domains and slopes generated by TIN module of ARC/INFO GIS. This study considered another regional slope stability analysis. 5 failure-driven factors 9the unstable slope map, geology, engineering soil, groundwater, and lineament density) were selected and used as data coverages for regional slope stability evaluation by geoenvironmental factors. These factors were weighted and overlayed in GIS. From the graph of cumulatave area (%) and instability index, finding critical points classified the instability indices. The most unstable slopes are located in the southern area of Mt. Eorae, Dabul-ri, and the eastern area of Junkok-ri in the first area is plane failure. Also, the expected orientations of failure are 59/338 and 86/090 (dip/dip direction).

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 추계 학술발표회 2차
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• pp.200-211
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• 2010

Tunnel Mapper, which is tunnel face survey system was used to conduct Face Mapping on the face of the tunnel that is under construction. Then, accuracy and utility value on the forecast of discontinuity were verified to verify the field application in order to present the measures for the use of the system for conducting research on the discontinuity. As result of the directivity verification following discontinuity‘s project, forecasted measurement and actually researched measurement error for the Dip direction and Dip angle was less than ${\pm}10$. Accuracy was 82.6% for Dip direction and 90.7% for Dip angle, which are high. Accordingly, face research discontinuity forecasting system's reliability level towards directivity is high. Tunnel Mapper, a tunnel face survey system can be leveraged to replace face's visual survey and to obtain objective information, enabling execution of the survey system that can automate face survey going beyond time and space related limitations.

• 자원환경지질
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• 제31권6호
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• pp.547-555
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• 1998

A new trigonometrical method for calculating total slip (T) of faulting is presented. The parameters for the calculations are used rake of fault striation, strike and dip of fault and of index planar structure such as bedding plane. The faults are groupped into three types. The direction of plunging of fault striation is out of a range ${\pm}90^{\circ}$ to the bedding dip direction in $360^{\circ}$ system, which is groupped into the type I. Meanwhile, the case of the direction lies in the above range can be separated into two different types, type II and type III, according to relative largeness of the angles rake of fault striation and i (see text). The type II has smaller rake than angle i and the type III has larger rake than angle i. Here I propose a few equations for calculating not only total slip (T) but strike slip (L) or dip slip (S) of the faulting. The equations are adapted selectively to the types of fault mentioned before. The limitation of the method is that the equations do not fit to polyphase faulting.

• 지질공학
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• 제19권4호
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• pp.517-528
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• 2009

충북 청원군과 보은군에 북서-남동 방향으로 관통하는 국도 25번 도로를 따라 약 5.7 km에 걸친 절취 사면의 안정성에 대한 통계학적 분석을 수행하였다. 이 구간은 전 사면에 걸쳐 직접적인 보강 방법과 간접적인 보호 대책을 사용하여 사면의 안정화 대책이 수립되었다. 총 30개소의 사면에서 사면의 방향성, 엽리와 층리, 벽개 및 절리구조의 방향성을 측정하였다. 스테레오 투영을 이용하여 분석한 결과 사면의 주방향성(경사/경사방향)은 1) $58^{\circ}/095^{\circ}$, 2) $60^{\circ}/296^{\circ}$ 및 3) $59^{\circ}/212^{\circ}$으로 3방향성이 우세하게 나타났다. 보강과 보호 대책이 수행된 사면의 빈도수와 사면의 경사방향의 분석에서 사면은 경사방향 $80-120^{\circ}$와 $280-320^{\circ}$의 방향성으로 주로 분포하며 사면의 경사방향 $0-80^{\circ}$(북쪽과 북동 방향)와 $120-160^{\circ}$(남동방향)의 사면은 연구지역에서 나타나지 않는다. 분석된 사면의 3가지 주방향성에 대하여 각각 사면의 파괴 양상을 분석하였으며 절리구조, 엽리와 층리 및 벽개구조의 교차나 교차 조합에 기인하여 여러 유형의 파괴가 발생할 수 있는 사면으로 분석되었다. 하지만 주방향성 3의 사면은 모든 파괴 양상이 발생할 수 있으나 통계상 빈도수에서 가장 적으며 지형상 소규모의 사면으로 형성되어 확률상 사면의 파괴가 발생할 가능성은 적은 것으로 분석되었다.

• Journal of Magnetics
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• 제2권1호
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• pp.16-21
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• 1997

Those were investigated, the crystallographic, morphological, and magnetic properties of barium ferrite film (SiO2/Si substrate) prepared by sol-gel dip coating. Appropriate sol was prepared by dissolvin barium and iron nitrate in ethylene glycol at 80$^{\circ}C$. To obtain the films, thermally oxidized p-type silicon substrate with (111) of crystallographic orientation were dipped into the sol, dried at 250$^{\circ}C$ to remove organic material, and heated at 800$^{\circ}C$ for 3 hours in air for the crystallization of barium ferrite. It was found that the particles of barium ferrite formed on the substrate exhibited needle-like shape placing parallel to the substrate and its c-axis is long axis direction. There was tendency that the coercive force in horizontal direction to the substrate was higher than that in vertical direction to it. This tendency was profound in large thickness.

• 자원환경지질
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• 제25권1호
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• pp.79-85
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• 1992

An Interpretation technique is presented to determine strike, dip, velocity and depth of 3-D planar layers from refraction or reflection traveltime curve. This interpretation technique determines the direction of emerging ray from the slope of the traveltime curve and traces the emerging ray to the refractor or reflector. The ray direction in the last layer is used to decide the normal vector to the refractor or reflector from whick its dip, strike and velocity are calculated. The vertical depth to the refractor or reflector is computed by using the intercept or zero-offset time and the ray direction in each layer. Some tests on the interpretation method are performed for the sysnthetic traveltimes generated in 3-D model layers and show that the paramerters of the model layers are accurately determined.

• 지질공학
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• 제12권3호
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• pp.345-360
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• 2002

이 연구는 활동 가능성이 높은 퇴적암 사면에 대한 안정성을 분석하기 위해 수치해석을 수행하고, 안정성을 확보할 수 있는 보강공법을 제시하기 위한 목적으로 수행되었다. 연구지역은 백악기 하양층군의 학봉 현무암층에 해당하는 지역으로 대부분이 현무암질 응회암으로 구성되어 있으며, 지질 구조요소로는 크게 1차 구조 요소인 층리와 2차 구조요소인 절리 및 단층이 확인되었다 층리는 단사구조를 보이는데, 대부분의 경우 경사방향이 120~160/15~25(dip direction/dip)이고, 절리의 경우에는 크게 3개 조의 절리군이 확인되는데 세트 1은 310~330/65~85, 세트 2는 230~250/70~85이며, 세트 3은 뚜렷한 연장성을 보이지는 않지만 020의 경사방향에 85$^{\circ}$이상의 고각을 보이고 있다. 사면에 대한 안정성 해석은 운동학적 해석과 한계평형 해석을 수행한 후, 수치해석 방법으로 FLAC을 이용하였다. FLAC은 유한차분법을 이용하는 연속체 역학모델이지만, Interfaces Module을 이용하여 UDEC과 같은 불연속체 모델의 해석효과를 얻을 수 있었다.

• 터널과지하공간
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• 제1권
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• pp.66-74
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• 1991

The block theory with stereographic projection was applied and analyzed on the tunnel section of Samcheok Coal Mine. The results were as follows ; 1) Prevail orientations of discontinuity of sandstone around the main driftway of Samcheok Coal Mine were $(327^{\circ},\;44^{\circ}),\;(13^{\circ},\;24^{\circ}),\;(204^{\circ},\;65^{\circ})$ and $(225^{\circ},\;77^{\circ})$ in dip and dip direction, respectively. 2) Movable blocks of the site were 0110, 0111, 1110(roof), 0100, 0110, 1110(right wall) and 0001, 1001, 1011(left wall). Because of the direction of tunnel, blocks of the left wall was safe. thus key blocks were those of the roof and the right wall. Maximum height of key block was larger than the width of the tunnel but 2m of the yielded zone is expected in general for 5m width tunnel. 3) It is shown that block theory is applicable to large cavern in hard rock analysis.